--- /dev/null
+/*
+ * Copyright (c) 2009, Microsoft Corporation.
+ *
+ * This program is free software; you can redistribute it and/or modify it
+ * under the terms and conditions of the GNU General Public License,
+ * version 2, as published by the Free Software Foundation.
+ *
+ * This program is distributed in the hope it will be useful, but WITHOUT
+ * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
+ * FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License for
+ * more details.
+ *
+ * You should have received a copy of the GNU General Public License along with
+ * this program; if not, write to the Free Software Foundation, Inc., 59 Temple
+ * Place - Suite 330, Boston, MA 02111-1307 USA.
+ *
+ * Authors:
+ * Haiyang Zhang <haiyangz@microsoft.com>
+ * Hank Janssen <hjanssen@microsoft.com>
+ * K. Y. Srinivasan <kys@microsoft.com>
+ */
+
+#include <linux/kernel.h>
+#include <linux/wait.h>
+#include <linux/sched.h>
+#include <linux/completion.h>
+#include <linux/string.h>
+#include <linux/mm.h>
+#include <linux/delay.h>
+#include <linux/init.h>
+#include <linux/slab.h>
+#include <linux/module.h>
+#include <linux/device.h>
+#include <linux/hyperv.h>
+#include <linux/mempool.h>
+#include <scsi/scsi.h>
+#include <scsi/scsi_cmnd.h>
+#include <scsi/scsi_host.h>
+#include <scsi/scsi_device.h>
+#include <scsi/scsi_tcq.h>
+#include <scsi/scsi_eh.h>
+#include <scsi/scsi_devinfo.h>
+#include <scsi/scsi_dbg.h>
+
+/*
+ * All wire protocol details (storage protocol between the guest and the host)
+ * are consolidated here.
+ *
+ * Begin protocol definitions.
+ */
+
+/*
+ * Version history:
+ * V1 Beta: 0.1
+ * V1 RC < 2008/1/31: 1.0
+ * V1 RC > 2008/1/31: 2.0
+ * Win7: 4.2
+ */
+
+#define VMSTOR_CURRENT_MAJOR 4
+#define VMSTOR_CURRENT_MINOR 2
+
+
+/* Packet structure describing virtual storage requests. */
+enum vstor_packet_operation {
+ VSTOR_OPERATION_COMPLETE_IO = 1,
+ VSTOR_OPERATION_REMOVE_DEVICE = 2,
+ VSTOR_OPERATION_EXECUTE_SRB = 3,
+ VSTOR_OPERATION_RESET_LUN = 4,
+ VSTOR_OPERATION_RESET_ADAPTER = 5,
+ VSTOR_OPERATION_RESET_BUS = 6,
+ VSTOR_OPERATION_BEGIN_INITIALIZATION = 7,
+ VSTOR_OPERATION_END_INITIALIZATION = 8,
+ VSTOR_OPERATION_QUERY_PROTOCOL_VERSION = 9,
+ VSTOR_OPERATION_QUERY_PROPERTIES = 10,
+ VSTOR_OPERATION_ENUMERATE_BUS = 11,
+ VSTOR_OPERATION_MAXIMUM = 11
+};
+
+/*
+ * Platform neutral description of a scsi request -
+ * this remains the same across the write regardless of 32/64 bit
+ * note: it's patterned off the SCSI_PASS_THROUGH structure
+ */
+#define STORVSC_MAX_CMD_LEN 0x10
+#define STORVSC_SENSE_BUFFER_SIZE 0x12
+#define STORVSC_MAX_BUF_LEN_WITH_PADDING 0x14
+
+struct vmscsi_request {
+ u16 length;
+ u8 srb_status;
+ u8 scsi_status;
+
+ u8 port_number;
+ u8 path_id;
+ u8 target_id;
+ u8 lun;
+
+ u8 cdb_length;
+ u8 sense_info_length;
+ u8 data_in;
+ u8 reserved;
+
+ u32 data_transfer_length;
+
+ union {
+ u8 cdb[STORVSC_MAX_CMD_LEN];
+ u8 sense_data[STORVSC_SENSE_BUFFER_SIZE];
+ u8 reserved_array[STORVSC_MAX_BUF_LEN_WITH_PADDING];
+ };
+} __attribute((packed));
+
+
+/*
+ * This structure is sent during the intialization phase to get the different
+ * properties of the channel.
+ */
+struct vmstorage_channel_properties {
+ u16 protocol_version;
+ u8 path_id;
+ u8 target_id;
+
+ /* Note: port number is only really known on the client side */
+ u32 port_number;
+ u32 flags;
+ u32 max_transfer_bytes;
+
+ /*
+ * This id is unique for each channel and will correspond with
+ * vendor specific data in the inquiry data.
+ */
+
+ u64 unique_id;
+} __packed;
+
+/* This structure is sent during the storage protocol negotiations. */
+struct vmstorage_protocol_version {
+ /* Major (MSW) and minor (LSW) version numbers. */
+ u16 major_minor;
+
+ /*
+ * Revision number is auto-incremented whenever this file is changed
+ * (See FILL_VMSTOR_REVISION macro above). Mismatch does not
+ * definitely indicate incompatibility--but it does indicate mismatched
+ * builds.
+ * This is only used on the windows side. Just set it to 0.
+ */
+ u16 revision;
+} __packed;
+
+/* Channel Property Flags */
+#define STORAGE_CHANNEL_REMOVABLE_FLAG 0x1
+#define STORAGE_CHANNEL_EMULATED_IDE_FLAG 0x2
+
+struct vstor_packet {
+ /* Requested operation type */
+ enum vstor_packet_operation operation;
+
+ /* Flags - see below for values */
+ u32 flags;
+
+ /* Status of the request returned from the server side. */
+ u32 status;
+
+ /* Data payload area */
+ union {
+ /*
+ * Structure used to forward SCSI commands from the
+ * client to the server.
+ */
+ struct vmscsi_request vm_srb;
+
+ /* Structure used to query channel properties. */
+ struct vmstorage_channel_properties storage_channel_properties;
+
+ /* Used during version negotiations. */
+ struct vmstorage_protocol_version version;
+ };
+} __packed;
+
+/*
+ * Packet Flags:
+ *
+ * This flag indicates that the server should send back a completion for this
+ * packet.
+ */
+
+#define REQUEST_COMPLETION_FLAG 0x1
+
+/* Matches Windows-end */
+enum storvsc_request_type {
+ WRITE_TYPE = 0,
+ READ_TYPE,
+ UNKNOWN_TYPE,
+};
+
+/*
+ * SRB status codes and masks; a subset of the codes used here.
+ */
+
+#define SRB_STATUS_AUTOSENSE_VALID 0x80
+#define SRB_STATUS_INVALID_LUN 0x20
+#define SRB_STATUS_SUCCESS 0x01
+#define SRB_STATUS_ERROR 0x04
+
+/*
+ * This is the end of Protocol specific defines.
+ */
+
+
+/*
+ * We setup a mempool to allocate request structures for this driver
+ * on a per-lun basis. The following define specifies the number of
+ * elements in the pool.
+ */
+
+#define STORVSC_MIN_BUF_NR 64
+static int storvsc_ringbuffer_size = (20 * PAGE_SIZE);
+
+module_param(storvsc_ringbuffer_size, int, S_IRUGO);
+MODULE_PARM_DESC(storvsc_ringbuffer_size, "Ring buffer size (bytes)");
+
+#define STORVSC_MAX_IO_REQUESTS 128
+
+/*
+ * In Hyper-V, each port/path/target maps to 1 scsi host adapter. In
+ * reality, the path/target is not used (ie always set to 0) so our
+ * scsi host adapter essentially has 1 bus with 1 target that contains
+ * up to 256 luns.
+ */
+#define STORVSC_MAX_LUNS_PER_TARGET 64
+#define STORVSC_MAX_TARGETS 1
+#define STORVSC_MAX_CHANNELS 1
+
+
+
+struct storvsc_cmd_request {
+ struct list_head entry;
+ struct scsi_cmnd *cmd;
+
+ unsigned int bounce_sgl_count;
+ struct scatterlist *bounce_sgl;
+
+ struct hv_device *device;
+
+ /* Synchronize the request/response if needed */
+ struct completion wait_event;
+
+ unsigned char *sense_buffer;
+ struct hv_multipage_buffer data_buffer;
+ struct vstor_packet vstor_packet;
+};
+
+
+/* A storvsc device is a device object that contains a vmbus channel */
+struct storvsc_device {
+ struct hv_device *device;
+
+ bool destroy;
+ bool drain_notify;
+ atomic_t num_outstanding_req;
+ struct Scsi_Host *host;
+
+ wait_queue_head_t waiting_to_drain;
+
+ /*
+ * Each unique Port/Path/Target represents 1 channel ie scsi
+ * controller. In reality, the pathid, targetid is always 0
+ * and the port is set by us
+ */
+ unsigned int port_number;
+ unsigned char path_id;
+ unsigned char target_id;
+
+ /* Used for vsc/vsp channel reset process */
+ struct storvsc_cmd_request init_request;
+ struct storvsc_cmd_request reset_request;
+};
+
+struct stor_mem_pools {
+ struct kmem_cache *request_pool;
+ mempool_t *request_mempool;
+};
+
+struct hv_host_device {
+ struct hv_device *dev;
+ unsigned int port;
+ unsigned char path;
+ unsigned char target;
+};
+
+struct storvsc_scan_work {
+ struct work_struct work;
+ struct Scsi_Host *host;
+ uint lun;
+};
+
+static void storvsc_bus_scan(struct work_struct *work)
+{
+ struct storvsc_scan_work *wrk;
+ int id, order_id;
+
+ wrk = container_of(work, struct storvsc_scan_work, work);
+ for (id = 0; id < wrk->host->max_id; ++id) {
+ if (wrk->host->reverse_ordering)
+ order_id = wrk->host->max_id - id - 1;
+ else
+ order_id = id;
+
+ scsi_scan_target(&wrk->host->shost_gendev, 0,
+ order_id, SCAN_WILD_CARD, 1);
+ }
+ kfree(wrk);
+}
+
+static void storvsc_remove_lun(struct work_struct *work)
+{
+ struct storvsc_scan_work *wrk;
+ struct scsi_device *sdev;
+
+ wrk = container_of(work, struct storvsc_scan_work, work);
+ if (!scsi_host_get(wrk->host))
+ goto done;
+
+ sdev = scsi_device_lookup(wrk->host, 0, 0, wrk->lun);
+
+ if (sdev) {
+ scsi_remove_device(sdev);
+ scsi_device_put(sdev);
+ }
+ scsi_host_put(wrk->host);
+
+done:
+ kfree(wrk);
+}
+
+/*
+ * Major/minor macros. Minor version is in LSB, meaning that earlier flat
+ * version numbers will be interpreted as "0.x" (i.e., 1 becomes 0.1).
+ */
+
+static inline u16 storvsc_get_version(u8 major, u8 minor)
+{
+ u16 version;
+
+ version = ((major << 8) | minor);
+ return version;
+}
+
+/*
+ * We can get incoming messages from the host that are not in response to
+ * messages that we have sent out. An example of this would be messages
+ * received by the guest to notify dynamic addition/removal of LUNs. To
+ * deal with potential race conditions where the driver may be in the
+ * midst of being unloaded when we might receive an unsolicited message
+ * from the host, we have implemented a mechanism to gurantee sequential
+ * consistency:
+ *
+ * 1) Once the device is marked as being destroyed, we will fail all
+ * outgoing messages.
+ * 2) We permit incoming messages when the device is being destroyed,
+ * only to properly account for messages already sent out.
+ */
+
+static inline struct storvsc_device *get_out_stor_device(
+ struct hv_device *device)
+{
+ struct storvsc_device *stor_device;
+
+ stor_device = hv_get_drvdata(device);
+
+ if (stor_device && stor_device->destroy)
+ stor_device = NULL;
+
+ return stor_device;
+}
+
+
+static inline void storvsc_wait_to_drain(struct storvsc_device *dev)
+{
+ dev->drain_notify = true;
+ wait_event(dev->waiting_to_drain,
+ atomic_read(&dev->num_outstanding_req) == 0);
+ dev->drain_notify = false;
+}
+
+static inline struct storvsc_device *get_in_stor_device(
+ struct hv_device *device)
+{
+ struct storvsc_device *stor_device;
+
+ stor_device = hv_get_drvdata(device);
+
+ if (!stor_device)
+ goto get_in_err;
+
+ /*
+ * If the device is being destroyed; allow incoming
+ * traffic only to cleanup outstanding requests.
+ */
+
+ if (stor_device->destroy &&
+ (atomic_read(&stor_device->num_outstanding_req) == 0))
+ stor_device = NULL;
+
+get_in_err:
+ return stor_device;
+
+}
+
+static void destroy_bounce_buffer(struct scatterlist *sgl,
+ unsigned int sg_count)
+{
+ int i;
+ struct page *page_buf;
+
+ for (i = 0; i < sg_count; i++) {
+ page_buf = sg_page((&sgl[i]));
+ if (page_buf != NULL)
+ __free_page(page_buf);
+ }
+
+ kfree(sgl);
+}
+
+static int do_bounce_buffer(struct scatterlist *sgl, unsigned int sg_count)
+{
+ int i;
+
+ /* No need to check */
+ if (sg_count < 2)
+ return -1;
+
+ /* We have at least 2 sg entries */
+ for (i = 0; i < sg_count; i++) {
+ if (i == 0) {
+ /* make sure 1st one does not have hole */
+ if (sgl[i].offset + sgl[i].length != PAGE_SIZE)
+ return i;
+ } else if (i == sg_count - 1) {
+ /* make sure last one does not have hole */
+ if (sgl[i].offset != 0)
+ return i;
+ } else {
+ /* make sure no hole in the middle */
+ if (sgl[i].length != PAGE_SIZE || sgl[i].offset != 0)
+ return i;
+ }
+ }
+ return -1;
+}
+
+static struct scatterlist *create_bounce_buffer(struct scatterlist *sgl,
+ unsigned int sg_count,
+ unsigned int len,
+ int write)
+{
+ int i;
+ int num_pages;
+ struct scatterlist *bounce_sgl;
+ struct page *page_buf;
+ unsigned int buf_len = ((write == WRITE_TYPE) ? 0 : PAGE_SIZE);
+
+ num_pages = ALIGN(len, PAGE_SIZE) >> PAGE_SHIFT;
+
+ bounce_sgl = kcalloc(num_pages, sizeof(struct scatterlist), GFP_ATOMIC);
+ if (!bounce_sgl)
+ return NULL;
+
+ for (i = 0; i < num_pages; i++) {
+ page_buf = alloc_page(GFP_ATOMIC);
+ if (!page_buf)
+ goto cleanup;
+ sg_set_page(&bounce_sgl[i], page_buf, buf_len, 0);
+ }
+
+ return bounce_sgl;
+
+cleanup:
+ destroy_bounce_buffer(bounce_sgl, num_pages);
+ return NULL;
+}
+
++/* Disgusting wrapper functions */
++static inline unsigned long sg_kmap_atomic(struct scatterlist *sgl, int idx)
++{
++ void *addr = kmap_atomic(sg_page(sgl + idx));
++ return (unsigned long)addr;
++}
++
++static inline void sg_kunmap_atomic(unsigned long addr)
++{
++ kunmap_atomic((void *)addr);
++}
++
++
+/* Assume the original sgl has enough room */
+static unsigned int copy_from_bounce_buffer(struct scatterlist *orig_sgl,
+ struct scatterlist *bounce_sgl,
+ unsigned int orig_sgl_count,
+ unsigned int bounce_sgl_count)
+{
+ int i;
+ int j = 0;
+ unsigned long src, dest;
+ unsigned int srclen, destlen, copylen;
+ unsigned int total_copied = 0;
+ unsigned long bounce_addr = 0;
+ unsigned long dest_addr = 0;
+ unsigned long flags;
+
+ local_irq_save(flags);
+
+ for (i = 0; i < orig_sgl_count; i++) {
- dest_addr = (unsigned long)kmap_atomic(sg_page((&orig_sgl[i])),
- KM_IRQ0) + orig_sgl[i].offset;
++ dest_addr = sg_kmap_atomic(orig_sgl,i) + orig_sgl[i].offset;
+ dest = dest_addr;
+ destlen = orig_sgl[i].length;
+
+ if (bounce_addr == 0)
- bounce_addr =
- (unsigned long)kmap_atomic(sg_page((&bounce_sgl[j])),
- KM_IRQ0);
++ bounce_addr = sg_kmap_atomic(bounce_sgl,j);
+
+ while (destlen) {
+ src = bounce_addr + bounce_sgl[j].offset;
+ srclen = bounce_sgl[j].length - bounce_sgl[j].offset;
+
+ copylen = min(srclen, destlen);
+ memcpy((void *)dest, (void *)src, copylen);
+
+ total_copied += copylen;
+ bounce_sgl[j].offset += copylen;
+ destlen -= copylen;
+ dest += copylen;
+
+ if (bounce_sgl[j].offset == bounce_sgl[j].length) {
+ /* full */
- kunmap_atomic((void *)bounce_addr, KM_IRQ0);
++ sg_kunmap_atomic(bounce_addr);
+ j++;
+
+ /*
+ * It is possible that the number of elements
+ * in the bounce buffer may not be equal to
+ * the number of elements in the original
+ * scatter list. Handle this correctly.
+ */
+
+ if (j == bounce_sgl_count) {
+ /*
+ * We are done; cleanup and return.
+ */
- kunmap_atomic((void *)(dest_addr -
- orig_sgl[i].offset),
- KM_IRQ0);
++ sg_kunmap_atomic(dest_addr - orig_sgl[i].offset);
+ local_irq_restore(flags);
+ return total_copied;
+ }
+
+ /* if we need to use another bounce buffer */
+ if (destlen || i != orig_sgl_count - 1)
- bounce_addr =
- (unsigned long)kmap_atomic(
- sg_page((&bounce_sgl[j])), KM_IRQ0);
++ bounce_addr = sg_kmap_atomic(bounce_sgl,j);
+ } else if (destlen == 0 && i == orig_sgl_count - 1) {
+ /* unmap the last bounce that is < PAGE_SIZE */
- kunmap_atomic((void *)bounce_addr, KM_IRQ0);
++ sg_kunmap_atomic(bounce_addr);
+ }
+ }
+
- kunmap_atomic((void *)(dest_addr - orig_sgl[i].offset),
- KM_IRQ0);
++ sg_kunmap_atomic(dest_addr - orig_sgl[i].offset);
+ }
+
+ local_irq_restore(flags);
+
+ return total_copied;
+}
+
+/* Assume the bounce_sgl has enough room ie using the create_bounce_buffer() */
+static unsigned int copy_to_bounce_buffer(struct scatterlist *orig_sgl,
+ struct scatterlist *bounce_sgl,
+ unsigned int orig_sgl_count)
+{
+ int i;
+ int j = 0;
+ unsigned long src, dest;
+ unsigned int srclen, destlen, copylen;
+ unsigned int total_copied = 0;
+ unsigned long bounce_addr = 0;
+ unsigned long src_addr = 0;
+ unsigned long flags;
+
+ local_irq_save(flags);
+
+ for (i = 0; i < orig_sgl_count; i++) {
- src_addr = (unsigned long)kmap_atomic(sg_page((&orig_sgl[i])),
- KM_IRQ0) + orig_sgl[i].offset;
++ src_addr = sg_kmap_atomic(orig_sgl,i) + orig_sgl[i].offset;
+ src = src_addr;
+ srclen = orig_sgl[i].length;
+
+ if (bounce_addr == 0)
- bounce_addr =
- (unsigned long)kmap_atomic(sg_page((&bounce_sgl[j])),
- KM_IRQ0);
++ bounce_addr = sg_kmap_atomic(bounce_sgl,j);
+
+ while (srclen) {
+ /* assume bounce offset always == 0 */
+ dest = bounce_addr + bounce_sgl[j].length;
+ destlen = PAGE_SIZE - bounce_sgl[j].length;
+
+ copylen = min(srclen, destlen);
+ memcpy((void *)dest, (void *)src, copylen);
+
+ total_copied += copylen;
+ bounce_sgl[j].length += copylen;
+ srclen -= copylen;
+ src += copylen;
+
+ if (bounce_sgl[j].length == PAGE_SIZE) {
+ /* full..move to next entry */
- kunmap_atomic((void *)bounce_addr, KM_IRQ0);
++ sg_kunmap_atomic(bounce_addr);
+ j++;
+
+ /* if we need to use another bounce buffer */
+ if (srclen || i != orig_sgl_count - 1)
- bounce_addr =
- (unsigned long)kmap_atomic(
- sg_page((&bounce_sgl[j])), KM_IRQ0);
++ bounce_addr = sg_kmap_atomic(bounce_sgl,j);
+
+ } else if (srclen == 0 && i == orig_sgl_count - 1) {
+ /* unmap the last bounce that is < PAGE_SIZE */
- kunmap_atomic((void *)bounce_addr, KM_IRQ0);
++ sg_kunmap_atomic(bounce_addr);
+ }
+ }
+
- kunmap_atomic((void *)(src_addr - orig_sgl[i].offset), KM_IRQ0);
++ sg_kunmap_atomic(src_addr - orig_sgl[i].offset);
+ }
+
+ local_irq_restore(flags);
+
+ return total_copied;
+}
+
+static int storvsc_channel_init(struct hv_device *device)
+{
+ struct storvsc_device *stor_device;
+ struct storvsc_cmd_request *request;
+ struct vstor_packet *vstor_packet;
+ int ret, t;
+
+ stor_device = get_out_stor_device(device);
+ if (!stor_device)
+ return -ENODEV;
+
+ request = &stor_device->init_request;
+ vstor_packet = &request->vstor_packet;
+
+ /*
+ * Now, initiate the vsc/vsp initialization protocol on the open
+ * channel
+ */
+ memset(request, 0, sizeof(struct storvsc_cmd_request));
+ init_completion(&request->wait_event);
+ vstor_packet->operation = VSTOR_OPERATION_BEGIN_INITIALIZATION;
+ vstor_packet->flags = REQUEST_COMPLETION_FLAG;
+
+ ret = vmbus_sendpacket(device->channel, vstor_packet,
+ sizeof(struct vstor_packet),
+ (unsigned long)request,
+ VM_PKT_DATA_INBAND,
+ VMBUS_DATA_PACKET_FLAG_COMPLETION_REQUESTED);
+ if (ret != 0)
+ goto cleanup;
+
+ t = wait_for_completion_timeout(&request->wait_event, 5*HZ);
+ if (t == 0) {
+ ret = -ETIMEDOUT;
+ goto cleanup;
+ }
+
+ if (vstor_packet->operation != VSTOR_OPERATION_COMPLETE_IO ||
+ vstor_packet->status != 0)
+ goto cleanup;
+
+
+ /* reuse the packet for version range supported */
+ memset(vstor_packet, 0, sizeof(struct vstor_packet));
+ vstor_packet->operation = VSTOR_OPERATION_QUERY_PROTOCOL_VERSION;
+ vstor_packet->flags = REQUEST_COMPLETION_FLAG;
+
+ vstor_packet->version.major_minor =
+ storvsc_get_version(VMSTOR_CURRENT_MAJOR, VMSTOR_CURRENT_MINOR);
+
+ /*
+ * The revision number is only used in Windows; set it to 0.
+ */
+ vstor_packet->version.revision = 0;
+
+ ret = vmbus_sendpacket(device->channel, vstor_packet,
+ sizeof(struct vstor_packet),
+ (unsigned long)request,
+ VM_PKT_DATA_INBAND,
+ VMBUS_DATA_PACKET_FLAG_COMPLETION_REQUESTED);
+ if (ret != 0)
+ goto cleanup;
+
+ t = wait_for_completion_timeout(&request->wait_event, 5*HZ);
+ if (t == 0) {
+ ret = -ETIMEDOUT;
+ goto cleanup;
+ }
+
+ if (vstor_packet->operation != VSTOR_OPERATION_COMPLETE_IO ||
+ vstor_packet->status != 0)
+ goto cleanup;
+
+
+ memset(vstor_packet, 0, sizeof(struct vstor_packet));
+ vstor_packet->operation = VSTOR_OPERATION_QUERY_PROPERTIES;
+ vstor_packet->flags = REQUEST_COMPLETION_FLAG;
+ vstor_packet->storage_channel_properties.port_number =
+ stor_device->port_number;
+
+ ret = vmbus_sendpacket(device->channel, vstor_packet,
+ sizeof(struct vstor_packet),
+ (unsigned long)request,
+ VM_PKT_DATA_INBAND,
+ VMBUS_DATA_PACKET_FLAG_COMPLETION_REQUESTED);
+
+ if (ret != 0)
+ goto cleanup;
+
+ t = wait_for_completion_timeout(&request->wait_event, 5*HZ);
+ if (t == 0) {
+ ret = -ETIMEDOUT;
+ goto cleanup;
+ }
+
+ if (vstor_packet->operation != VSTOR_OPERATION_COMPLETE_IO ||
+ vstor_packet->status != 0)
+ goto cleanup;
+
+ stor_device->path_id = vstor_packet->storage_channel_properties.path_id;
+ stor_device->target_id
+ = vstor_packet->storage_channel_properties.target_id;
+
+ memset(vstor_packet, 0, sizeof(struct vstor_packet));
+ vstor_packet->operation = VSTOR_OPERATION_END_INITIALIZATION;
+ vstor_packet->flags = REQUEST_COMPLETION_FLAG;
+
+ ret = vmbus_sendpacket(device->channel, vstor_packet,
+ sizeof(struct vstor_packet),
+ (unsigned long)request,
+ VM_PKT_DATA_INBAND,
+ VMBUS_DATA_PACKET_FLAG_COMPLETION_REQUESTED);
+
+ if (ret != 0)
+ goto cleanup;
+
+ t = wait_for_completion_timeout(&request->wait_event, 5*HZ);
+ if (t == 0) {
+ ret = -ETIMEDOUT;
+ goto cleanup;
+ }
+
+ if (vstor_packet->operation != VSTOR_OPERATION_COMPLETE_IO ||
+ vstor_packet->status != 0)
+ goto cleanup;
+
+
+cleanup:
+ return ret;
+}
+
+
+static void storvsc_command_completion(struct storvsc_cmd_request *cmd_request)
+{
+ struct scsi_cmnd *scmnd = cmd_request->cmd;
+ struct hv_host_device *host_dev = shost_priv(scmnd->device->host);
+ void (*scsi_done_fn)(struct scsi_cmnd *);
+ struct scsi_sense_hdr sense_hdr;
+ struct vmscsi_request *vm_srb;
+ struct storvsc_scan_work *wrk;
+ struct stor_mem_pools *memp = scmnd->device->hostdata;
+
+ vm_srb = &cmd_request->vstor_packet.vm_srb;
+ if (cmd_request->bounce_sgl_count) {
+ if (vm_srb->data_in == READ_TYPE)
+ copy_from_bounce_buffer(scsi_sglist(scmnd),
+ cmd_request->bounce_sgl,
+ scsi_sg_count(scmnd),
+ cmd_request->bounce_sgl_count);
+ destroy_bounce_buffer(cmd_request->bounce_sgl,
+ cmd_request->bounce_sgl_count);
+ }
+
+ /*
+ * If there is an error; offline the device since all
+ * error recovery strategies would have already been
+ * deployed on the host side.
+ */
+ if (vm_srb->srb_status == SRB_STATUS_ERROR)
+ scmnd->result = DID_TARGET_FAILURE << 16;
+ else
+ scmnd->result = vm_srb->scsi_status;
+
+ /*
+ * If the LUN is invalid; remove the device.
+ */
+ if (vm_srb->srb_status == SRB_STATUS_INVALID_LUN) {
+ struct storvsc_device *stor_dev;
+ struct hv_device *dev = host_dev->dev;
+ struct Scsi_Host *host;
+
+ stor_dev = get_in_stor_device(dev);
+ host = stor_dev->host;
+
+ wrk = kmalloc(sizeof(struct storvsc_scan_work),
+ GFP_ATOMIC);
+ if (!wrk) {
+ scmnd->result = DID_TARGET_FAILURE << 16;
+ } else {
+ wrk->host = host;
+ wrk->lun = vm_srb->lun;
+ INIT_WORK(&wrk->work, storvsc_remove_lun);
+ schedule_work(&wrk->work);
+ }
+ }
+
+ if (scmnd->result) {
+ if (scsi_normalize_sense(scmnd->sense_buffer,
+ SCSI_SENSE_BUFFERSIZE, &sense_hdr))
+ scsi_print_sense_hdr("storvsc", &sense_hdr);
+ }
+
+ scsi_set_resid(scmnd,
+ cmd_request->data_buffer.len -
+ vm_srb->data_transfer_length);
+
+ scsi_done_fn = scmnd->scsi_done;
+
+ scmnd->host_scribble = NULL;
+ scmnd->scsi_done = NULL;
+
+ scsi_done_fn(scmnd);
+
+ mempool_free(cmd_request, memp->request_mempool);
+}
+
+static void storvsc_on_io_completion(struct hv_device *device,
+ struct vstor_packet *vstor_packet,
+ struct storvsc_cmd_request *request)
+{
+ struct storvsc_device *stor_device;
+ struct vstor_packet *stor_pkt;
+
+ stor_device = hv_get_drvdata(device);
+ stor_pkt = &request->vstor_packet;
+
+ /*
+ * The current SCSI handling on the host side does
+ * not correctly handle:
+ * INQUIRY command with page code parameter set to 0x80
+ * MODE_SENSE command with cmd[2] == 0x1c
+ *
+ * Setup srb and scsi status so this won't be fatal.
+ * We do this so we can distinguish truly fatal failues
+ * (srb status == 0x4) and off-line the device in that case.
+ */
+
+ if ((stor_pkt->vm_srb.cdb[0] == INQUIRY) ||
+ (stor_pkt->vm_srb.cdb[0] == MODE_SENSE)) {
+ vstor_packet->vm_srb.scsi_status = 0;
+ vstor_packet->vm_srb.srb_status = SRB_STATUS_SUCCESS;
+ }
+
+
+ /* Copy over the status...etc */
+ stor_pkt->vm_srb.scsi_status = vstor_packet->vm_srb.scsi_status;
+ stor_pkt->vm_srb.srb_status = vstor_packet->vm_srb.srb_status;
+ stor_pkt->vm_srb.sense_info_length =
+ vstor_packet->vm_srb.sense_info_length;
+
+ if (vstor_packet->vm_srb.scsi_status != 0 ||
+ vstor_packet->vm_srb.srb_status != SRB_STATUS_SUCCESS){
+ dev_warn(&device->device,
+ "cmd 0x%x scsi status 0x%x srb status 0x%x\n",
+ stor_pkt->vm_srb.cdb[0],
+ vstor_packet->vm_srb.scsi_status,
+ vstor_packet->vm_srb.srb_status);
+ }
+
+ if ((vstor_packet->vm_srb.scsi_status & 0xFF) == 0x02) {
+ /* CHECK_CONDITION */
+ if (vstor_packet->vm_srb.srb_status &
+ SRB_STATUS_AUTOSENSE_VALID) {
+ /* autosense data available */
+ dev_warn(&device->device,
+ "stor pkt %p autosense data valid - len %d\n",
+ request,
+ vstor_packet->vm_srb.sense_info_length);
+
+ memcpy(request->sense_buffer,
+ vstor_packet->vm_srb.sense_data,
+ vstor_packet->vm_srb.sense_info_length);
+
+ }
+ }
+
+ stor_pkt->vm_srb.data_transfer_length =
+ vstor_packet->vm_srb.data_transfer_length;
+
+ storvsc_command_completion(request);
+
+ if (atomic_dec_and_test(&stor_device->num_outstanding_req) &&
+ stor_device->drain_notify)
+ wake_up(&stor_device->waiting_to_drain);
+
+
+}
+
+static void storvsc_on_receive(struct hv_device *device,
+ struct vstor_packet *vstor_packet,
+ struct storvsc_cmd_request *request)
+{
+ struct storvsc_scan_work *work;
+ struct storvsc_device *stor_device;
+
+ switch (vstor_packet->operation) {
+ case VSTOR_OPERATION_COMPLETE_IO:
+ storvsc_on_io_completion(device, vstor_packet, request);
+ break;
+
+ case VSTOR_OPERATION_REMOVE_DEVICE:
+ case VSTOR_OPERATION_ENUMERATE_BUS:
+ stor_device = get_in_stor_device(device);
+ work = kmalloc(sizeof(struct storvsc_scan_work), GFP_ATOMIC);
+ if (!work)
+ return;
+
+ INIT_WORK(&work->work, storvsc_bus_scan);
+ work->host = stor_device->host;
+ schedule_work(&work->work);
+ break;
+
+ default:
+ break;
+ }
+}
+
+static void storvsc_on_channel_callback(void *context)
+{
+ struct hv_device *device = (struct hv_device *)context;
+ struct storvsc_device *stor_device;
+ u32 bytes_recvd;
+ u64 request_id;
+ unsigned char packet[ALIGN(sizeof(struct vstor_packet), 8)];
+ struct storvsc_cmd_request *request;
+ int ret;
+
+
+ stor_device = get_in_stor_device(device);
+ if (!stor_device)
+ return;
+
+ do {
+ ret = vmbus_recvpacket(device->channel, packet,
+ ALIGN(sizeof(struct vstor_packet), 8),
+ &bytes_recvd, &request_id);
+ if (ret == 0 && bytes_recvd > 0) {
+
+ request = (struct storvsc_cmd_request *)
+ (unsigned long)request_id;
+
+ if ((request == &stor_device->init_request) ||
+ (request == &stor_device->reset_request)) {
+
+ memcpy(&request->vstor_packet, packet,
+ sizeof(struct vstor_packet));
+ complete(&request->wait_event);
+ } else {
+ storvsc_on_receive(device,
+ (struct vstor_packet *)packet,
+ request);
+ }
+ } else {
+ break;
+ }
+ } while (1);
+
+ return;
+}
+
+static int storvsc_connect_to_vsp(struct hv_device *device, u32 ring_size)
+{
+ struct vmstorage_channel_properties props;
+ int ret;
+
+ memset(&props, 0, sizeof(struct vmstorage_channel_properties));
+
+ ret = vmbus_open(device->channel,
+ ring_size,
+ ring_size,
+ (void *)&props,
+ sizeof(struct vmstorage_channel_properties),
+ storvsc_on_channel_callback, device);
+
+ if (ret != 0)
+ return ret;
+
+ ret = storvsc_channel_init(device);
+
+ return ret;
+}
+
+static int storvsc_dev_remove(struct hv_device *device)
+{
+ struct storvsc_device *stor_device;
+ unsigned long flags;
+
+ stor_device = hv_get_drvdata(device);
+
+ spin_lock_irqsave(&device->channel->inbound_lock, flags);
+ stor_device->destroy = true;
+ spin_unlock_irqrestore(&device->channel->inbound_lock, flags);
+
+ /*
+ * At this point, all outbound traffic should be disable. We
+ * only allow inbound traffic (responses) to proceed so that
+ * outstanding requests can be completed.
+ */
+
+ storvsc_wait_to_drain(stor_device);
+
+ /*
+ * Since we have already drained, we don't need to busy wait
+ * as was done in final_release_stor_device()
+ * Note that we cannot set the ext pointer to NULL until
+ * we have drained - to drain the outgoing packets, we need to
+ * allow incoming packets.
+ */
+ spin_lock_irqsave(&device->channel->inbound_lock, flags);
+ hv_set_drvdata(device, NULL);
+ spin_unlock_irqrestore(&device->channel->inbound_lock, flags);
+
+ /* Close the channel */
+ vmbus_close(device->channel);
+
+ kfree(stor_device);
+ return 0;
+}
+
+static int storvsc_do_io(struct hv_device *device,
+ struct storvsc_cmd_request *request)
+{
+ struct storvsc_device *stor_device;
+ struct vstor_packet *vstor_packet;
+ int ret = 0;
+
+ vstor_packet = &request->vstor_packet;
+ stor_device = get_out_stor_device(device);
+
+ if (!stor_device)
+ return -ENODEV;
+
+
+ request->device = device;
+
+
+ vstor_packet->flags |= REQUEST_COMPLETION_FLAG;
+
+ vstor_packet->vm_srb.length = sizeof(struct vmscsi_request);
+
+
+ vstor_packet->vm_srb.sense_info_length = STORVSC_SENSE_BUFFER_SIZE;
+
+
+ vstor_packet->vm_srb.data_transfer_length =
+ request->data_buffer.len;
+
+ vstor_packet->operation = VSTOR_OPERATION_EXECUTE_SRB;
+
+ if (request->data_buffer.len) {
+ ret = vmbus_sendpacket_multipagebuffer(device->channel,
+ &request->data_buffer,
+ vstor_packet,
+ sizeof(struct vstor_packet),
+ (unsigned long)request);
+ } else {
+ ret = vmbus_sendpacket(device->channel, vstor_packet,
+ sizeof(struct vstor_packet),
+ (unsigned long)request,
+ VM_PKT_DATA_INBAND,
+ VMBUS_DATA_PACKET_FLAG_COMPLETION_REQUESTED);
+ }
+
+ if (ret != 0)
+ return ret;
+
+ atomic_inc(&stor_device->num_outstanding_req);
+
+ return ret;
+}
+
+static int storvsc_device_alloc(struct scsi_device *sdevice)
+{
+ struct stor_mem_pools *memp;
+ int number = STORVSC_MIN_BUF_NR;
+
+ memp = kzalloc(sizeof(struct stor_mem_pools), GFP_KERNEL);
+ if (!memp)
+ return -ENOMEM;
+
+ memp->request_pool =
+ kmem_cache_create(dev_name(&sdevice->sdev_dev),
+ sizeof(struct storvsc_cmd_request), 0,
+ SLAB_HWCACHE_ALIGN, NULL);
+
+ if (!memp->request_pool)
+ goto err0;
+
+ memp->request_mempool = mempool_create(number, mempool_alloc_slab,
+ mempool_free_slab,
+ memp->request_pool);
+
+ if (!memp->request_mempool)
+ goto err1;
+
+ sdevice->hostdata = memp;
+
+ return 0;
+
+err1:
+ kmem_cache_destroy(memp->request_pool);
+
+err0:
+ kfree(memp);
+ return -ENOMEM;
+}
+
+static void storvsc_device_destroy(struct scsi_device *sdevice)
+{
+ struct stor_mem_pools *memp = sdevice->hostdata;
+
+ mempool_destroy(memp->request_mempool);
+ kmem_cache_destroy(memp->request_pool);
+ kfree(memp);
+ sdevice->hostdata = NULL;
+}
+
+static int storvsc_device_configure(struct scsi_device *sdevice)
+{
+ scsi_adjust_queue_depth(sdevice, MSG_SIMPLE_TAG,
+ STORVSC_MAX_IO_REQUESTS);
+
+ blk_queue_max_segment_size(sdevice->request_queue, PAGE_SIZE);
+
+ blk_queue_bounce_limit(sdevice->request_queue, BLK_BOUNCE_ANY);
+
+ return 0;
+}
+
+static int storvsc_get_chs(struct scsi_device *sdev, struct block_device * bdev,
+ sector_t capacity, int *info)
+{
+ sector_t nsect = capacity;
+ sector_t cylinders = nsect;
+ int heads, sectors_pt;
+
+ /*
+ * We are making up these values; let us keep it simple.
+ */
+ heads = 0xff;
+ sectors_pt = 0x3f; /* Sectors per track */
+ sector_div(cylinders, heads * sectors_pt);
+ if ((sector_t)(cylinders + 1) * heads * sectors_pt < nsect)
+ cylinders = 0xffff;
+
+ info[0] = heads;
+ info[1] = sectors_pt;
+ info[2] = (int)cylinders;
+
+ return 0;
+}
+
+static int storvsc_host_reset_handler(struct scsi_cmnd *scmnd)
+{
+ struct hv_host_device *host_dev = shost_priv(scmnd->device->host);
+ struct hv_device *device = host_dev->dev;
+
+ struct storvsc_device *stor_device;
+ struct storvsc_cmd_request *request;
+ struct vstor_packet *vstor_packet;
+ int ret, t;
+
+
+ stor_device = get_out_stor_device(device);
+ if (!stor_device)
+ return FAILED;
+
+ request = &stor_device->reset_request;
+ vstor_packet = &request->vstor_packet;
+
+ init_completion(&request->wait_event);
+
+ vstor_packet->operation = VSTOR_OPERATION_RESET_BUS;
+ vstor_packet->flags = REQUEST_COMPLETION_FLAG;
+ vstor_packet->vm_srb.path_id = stor_device->path_id;
+
+ ret = vmbus_sendpacket(device->channel, vstor_packet,
+ sizeof(struct vstor_packet),
+ (unsigned long)&stor_device->reset_request,
+ VM_PKT_DATA_INBAND,
+ VMBUS_DATA_PACKET_FLAG_COMPLETION_REQUESTED);
+ if (ret != 0)
+ return FAILED;
+
+ t = wait_for_completion_timeout(&request->wait_event, 5*HZ);
+ if (t == 0)
+ return TIMEOUT_ERROR;
+
+
+ /*
+ * At this point, all outstanding requests in the adapter
+ * should have been flushed out and return to us
+ */
+
+ return SUCCESS;
+}
+
+static bool storvsc_scsi_cmd_ok(struct scsi_cmnd *scmnd)
+{
+ bool allowed = true;
+ u8 scsi_op = scmnd->cmnd[0];
+
+ switch (scsi_op) {
+ /*
+ * smartd sends this command and the host does not handle
+ * this. So, don't send it.
+ */
+ case SET_WINDOW:
+ scmnd->result = ILLEGAL_REQUEST << 16;
+ allowed = false;
+ break;
+ default:
+ break;
+ }
+ return allowed;
+}
+
+static int storvsc_queuecommand(struct Scsi_Host *host, struct scsi_cmnd *scmnd)
+{
+ int ret;
+ struct hv_host_device *host_dev = shost_priv(host);
+ struct hv_device *dev = host_dev->dev;
+ struct storvsc_cmd_request *cmd_request;
+ unsigned int request_size = 0;
+ int i;
+ struct scatterlist *sgl;
+ unsigned int sg_count = 0;
+ struct vmscsi_request *vm_srb;
+ struct stor_mem_pools *memp = scmnd->device->hostdata;
+
+ if (!storvsc_scsi_cmd_ok(scmnd)) {
+ scmnd->scsi_done(scmnd);
+ return 0;
+ }
+
+ request_size = sizeof(struct storvsc_cmd_request);
+
+ cmd_request = mempool_alloc(memp->request_mempool,
+ GFP_ATOMIC);
+
+ /*
+ * We might be invoked in an interrupt context; hence
+ * mempool_alloc() can fail.
+ */
+ if (!cmd_request)
+ return SCSI_MLQUEUE_DEVICE_BUSY;
+
+ memset(cmd_request, 0, sizeof(struct storvsc_cmd_request));
+
+ /* Setup the cmd request */
+ cmd_request->cmd = scmnd;
+
+ scmnd->host_scribble = (unsigned char *)cmd_request;
+
+ vm_srb = &cmd_request->vstor_packet.vm_srb;
+
+
+ /* Build the SRB */
+ switch (scmnd->sc_data_direction) {
+ case DMA_TO_DEVICE:
+ vm_srb->data_in = WRITE_TYPE;
+ break;
+ case DMA_FROM_DEVICE:
+ vm_srb->data_in = READ_TYPE;
+ break;
+ default:
+ vm_srb->data_in = UNKNOWN_TYPE;
+ break;
+ }
+
+
+ vm_srb->port_number = host_dev->port;
+ vm_srb->path_id = scmnd->device->channel;
+ vm_srb->target_id = scmnd->device->id;
+ vm_srb->lun = scmnd->device->lun;
+
+ vm_srb->cdb_length = scmnd->cmd_len;
+
+ memcpy(vm_srb->cdb, scmnd->cmnd, vm_srb->cdb_length);
+
+ cmd_request->sense_buffer = scmnd->sense_buffer;
+
+
+ cmd_request->data_buffer.len = scsi_bufflen(scmnd);
+ if (scsi_sg_count(scmnd)) {
+ sgl = (struct scatterlist *)scsi_sglist(scmnd);
+ sg_count = scsi_sg_count(scmnd);
+
+ /* check if we need to bounce the sgl */
+ if (do_bounce_buffer(sgl, scsi_sg_count(scmnd)) != -1) {
+ cmd_request->bounce_sgl =
+ create_bounce_buffer(sgl, scsi_sg_count(scmnd),
+ scsi_bufflen(scmnd),
+ vm_srb->data_in);
+ if (!cmd_request->bounce_sgl) {
+ ret = SCSI_MLQUEUE_HOST_BUSY;
+ goto queue_error;
+ }
+
+ cmd_request->bounce_sgl_count =
+ ALIGN(scsi_bufflen(scmnd), PAGE_SIZE) >>
+ PAGE_SHIFT;
+
+ if (vm_srb->data_in == WRITE_TYPE)
+ copy_to_bounce_buffer(sgl,
+ cmd_request->bounce_sgl,
+ scsi_sg_count(scmnd));
+
+ sgl = cmd_request->bounce_sgl;
+ sg_count = cmd_request->bounce_sgl_count;
+ }
+
+ cmd_request->data_buffer.offset = sgl[0].offset;
+
+ for (i = 0; i < sg_count; i++)
+ cmd_request->data_buffer.pfn_array[i] =
+ page_to_pfn(sg_page((&sgl[i])));
+
+ } else if (scsi_sglist(scmnd)) {
+ cmd_request->data_buffer.offset =
+ virt_to_phys(scsi_sglist(scmnd)) & (PAGE_SIZE-1);
+ cmd_request->data_buffer.pfn_array[0] =
+ virt_to_phys(scsi_sglist(scmnd)) >> PAGE_SHIFT;
+ }
+
+ /* Invokes the vsc to start an IO */
+ ret = storvsc_do_io(dev, cmd_request);
+
+ if (ret == -EAGAIN) {
+ /* no more space */
+
+ if (cmd_request->bounce_sgl_count) {
+ destroy_bounce_buffer(cmd_request->bounce_sgl,
+ cmd_request->bounce_sgl_count);
+
+ ret = SCSI_MLQUEUE_DEVICE_BUSY;
+ goto queue_error;
+ }
+ }
+
+ return 0;
+
+queue_error:
+ mempool_free(cmd_request, memp->request_mempool);
+ scmnd->host_scribble = NULL;
+ return ret;
+}
+
+static struct scsi_host_template scsi_driver = {
+ .module = THIS_MODULE,
+ .name = "storvsc_host_t",
+ .bios_param = storvsc_get_chs,
+ .queuecommand = storvsc_queuecommand,
+ .eh_host_reset_handler = storvsc_host_reset_handler,
+ .slave_alloc = storvsc_device_alloc,
+ .slave_destroy = storvsc_device_destroy,
+ .slave_configure = storvsc_device_configure,
+ .cmd_per_lun = 1,
+ /* 64 max_queue * 1 target */
+ .can_queue = STORVSC_MAX_IO_REQUESTS*STORVSC_MAX_TARGETS,
+ .this_id = -1,
+ /* no use setting to 0 since ll_blk_rw reset it to 1 */
+ /* currently 32 */
+ .sg_tablesize = MAX_MULTIPAGE_BUFFER_COUNT,
+ .use_clustering = DISABLE_CLUSTERING,
+ /* Make sure we dont get a sg segment crosses a page boundary */
+ .dma_boundary = PAGE_SIZE-1,
+};
+
+enum {
+ SCSI_GUID,
+ IDE_GUID,
+};
+
+static const struct hv_vmbus_device_id id_table[] = {
+ /* SCSI guid */
+ { VMBUS_DEVICE(0xd9, 0x63, 0x61, 0xba, 0xa1, 0x04, 0x29, 0x4d,
+ 0xb6, 0x05, 0x72, 0xe2, 0xff, 0xb1, 0xdc, 0x7f)
+ .driver_data = SCSI_GUID },
+ /* IDE guid */
+ { VMBUS_DEVICE(0x32, 0x26, 0x41, 0x32, 0xcb, 0x86, 0xa2, 0x44,
+ 0x9b, 0x5c, 0x50, 0xd1, 0x41, 0x73, 0x54, 0xf5)
+ .driver_data = IDE_GUID },
+ { },
+};
+
+MODULE_DEVICE_TABLE(vmbus, id_table);
+
+static int storvsc_probe(struct hv_device *device,
+ const struct hv_vmbus_device_id *dev_id)
+{
+ int ret;
+ struct Scsi_Host *host;
+ struct hv_host_device *host_dev;
+ bool dev_is_ide = ((dev_id->driver_data == IDE_GUID) ? true : false);
+ int target = 0;
+ struct storvsc_device *stor_device;
+
+ host = scsi_host_alloc(&scsi_driver,
+ sizeof(struct hv_host_device));
+ if (!host)
+ return -ENOMEM;
+
+ host_dev = shost_priv(host);
+ memset(host_dev, 0, sizeof(struct hv_host_device));
+
+ host_dev->port = host->host_no;
+ host_dev->dev = device;
+
+
+ stor_device = kzalloc(sizeof(struct storvsc_device), GFP_KERNEL);
+ if (!stor_device) {
+ ret = -ENOMEM;
+ goto err_out0;
+ }
+
+ stor_device->destroy = false;
+ init_waitqueue_head(&stor_device->waiting_to_drain);
+ stor_device->device = device;
+ stor_device->host = host;
+ hv_set_drvdata(device, stor_device);
+
+ stor_device->port_number = host->host_no;
+ ret = storvsc_connect_to_vsp(device, storvsc_ringbuffer_size);
+ if (ret)
+ goto err_out1;
+
+ host_dev->path = stor_device->path_id;
+ host_dev->target = stor_device->target_id;
+
+ /* max # of devices per target */
+ host->max_lun = STORVSC_MAX_LUNS_PER_TARGET;
+ /* max # of targets per channel */
+ host->max_id = STORVSC_MAX_TARGETS;
+ /* max # of channels */
+ host->max_channel = STORVSC_MAX_CHANNELS - 1;
+ /* max cmd length */
+ host->max_cmd_len = STORVSC_MAX_CMD_LEN;
+
+ /* Register the HBA and start the scsi bus scan */
+ ret = scsi_add_host(host, &device->device);
+ if (ret != 0)
+ goto err_out2;
+
+ if (!dev_is_ide) {
+ scsi_scan_host(host);
+ } else {
+ target = (device->dev_instance.b[5] << 8 |
+ device->dev_instance.b[4]);
+ ret = scsi_add_device(host, 0, target, 0);
+ if (ret) {
+ scsi_remove_host(host);
+ goto err_out2;
+ }
+ }
+ return 0;
+
+err_out2:
+ /*
+ * Once we have connected with the host, we would need to
+ * to invoke storvsc_dev_remove() to rollback this state and
+ * this call also frees up the stor_device; hence the jump around
+ * err_out1 label.
+ */
+ storvsc_dev_remove(device);
+ goto err_out0;
+
+err_out1:
+ kfree(stor_device);
+
+err_out0:
+ scsi_host_put(host);
+ return ret;
+}
+
+static int storvsc_remove(struct hv_device *dev)
+{
+ struct storvsc_device *stor_device = hv_get_drvdata(dev);
+ struct Scsi_Host *host = stor_device->host;
+
+ scsi_remove_host(host);
+ storvsc_dev_remove(dev);
+ scsi_host_put(host);
+
+ return 0;
+}
+
+static struct hv_driver storvsc_drv = {
+ .name = KBUILD_MODNAME,
+ .id_table = id_table,
+ .probe = storvsc_probe,
+ .remove = storvsc_remove,
+};
+
+static int __init storvsc_drv_init(void)
+{
+ u32 max_outstanding_req_per_channel;
+
+ /*
+ * Divide the ring buffer data size (which is 1 page less
+ * than the ring buffer size since that page is reserved for
+ * the ring buffer indices) by the max request size (which is
+ * vmbus_channel_packet_multipage_buffer + struct vstor_packet + u64)
+ */
+ max_outstanding_req_per_channel =
+ ((storvsc_ringbuffer_size - PAGE_SIZE) /
+ ALIGN(MAX_MULTIPAGE_BUFFER_PACKET +
+ sizeof(struct vstor_packet) + sizeof(u64),
+ sizeof(u64)));
+
+ if (max_outstanding_req_per_channel <
+ STORVSC_MAX_IO_REQUESTS)
+ return -EINVAL;
+
+ return vmbus_driver_register(&storvsc_drv);
+}
+
+static void __exit storvsc_drv_exit(void)
+{
+ vmbus_driver_unregister(&storvsc_drv);
+}
+
+MODULE_LICENSE("GPL");
+MODULE_VERSION(HV_DRV_VERSION);
+MODULE_DESCRIPTION("Microsoft Hyper-V virtual storage driver");
+module_init(storvsc_drv_init);
+module_exit(storvsc_drv_exit);
--- /dev/null
+/*
+ * zcache.c
+ *
+ * Copyright (c) 2010-2012, Dan Magenheimer, Oracle Corp.
+ * Copyright (c) 2010,2011, Nitin Gupta
+ *
+ * Zcache provides an in-kernel "host implementation" for transcendent memory
+ * and, thus indirectly, for cleancache and frontswap. Zcache includes two
+ * page-accessible memory [1] interfaces, both utilizing lzo1x compression:
+ * 1) "compression buddies" ("zbud") is used for ephemeral pages
+ * 2) xvmalloc is used for persistent pages.
+ * Xvmalloc (based on the TLSF allocator) has very low fragmentation
+ * so maximizes space efficiency, while zbud allows pairs (and potentially,
+ * in the future, more than a pair of) compressed pages to be closely linked
+ * so that reclaiming can be done via the kernel's physical-page-oriented
+ * "shrinker" interface.
+ *
+ * [1] For a definition of page-accessible memory (aka PAM), see:
+ * http://marc.info/?l=linux-mm&m=127811271605009
+ * RAMSTER TODO:
+ * - handle remotifying of buddied pages (see zbud_remotify_zbpg)
+ * - kernel boot params: nocleancache/nofrontswap don't always work?!?
+ */
+
+#include <linux/module.h>
+#include <linux/cpu.h>
+#include <linux/highmem.h>
+#include <linux/list.h>
+#include <linux/lzo.h>
+#include <linux/slab.h>
+#include <linux/spinlock.h>
+#include <linux/types.h>
+#include <linux/atomic.h>
+#include <linux/math64.h>
+#include "tmem.h"
+#include "zcache.h"
+#include "ramster.h"
+#include "cluster/tcp.h"
+
+#include "xvmalloc.h" /* temporary until change to zsmalloc */
+
+#define RAMSTER_TESTING
+
+#if (!defined(CONFIG_CLEANCACHE) && !defined(CONFIG_FRONTSWAP))
+#error "ramster is useless without CONFIG_CLEANCACHE or CONFIG_FRONTSWAP"
+#endif
+#ifdef CONFIG_CLEANCACHE
+#include <linux/cleancache.h>
+#endif
+#ifdef CONFIG_FRONTSWAP
+#include <linux/frontswap.h>
+#endif
+
+enum ramster_remotify_op {
+ RAMSTER_REMOTIFY_EPH_PUT,
+ RAMSTER_REMOTIFY_PERS_PUT,
+ RAMSTER_REMOTIFY_FLUSH_PAGE,
+ RAMSTER_REMOTIFY_FLUSH_OBJ,
+ RAMSTER_INTRANSIT_PERS
+};
+
+struct ramster_remotify_hdr {
+ enum ramster_remotify_op op;
+ struct list_head list;
+};
+
+#define ZBH_SENTINEL 0x43214321
+#define ZBPG_SENTINEL 0xdeadbeef
+
+#define ZBUD_MAX_BUDS 2
+
+struct zbud_hdr {
+ struct ramster_remotify_hdr rem_op;
+ uint16_t client_id;
+ uint16_t pool_id;
+ struct tmem_oid oid;
+ uint32_t index;
+ uint16_t size; /* compressed size in bytes, zero means unused */
+ DECL_SENTINEL
+};
+
+#define ZVH_SENTINEL 0x43214321
+static const int zv_max_page_size = (PAGE_SIZE / 8) * 7;
+
+struct zv_hdr {
+ struct ramster_remotify_hdr rem_op;
+ uint16_t client_id;
+ uint16_t pool_id;
+ struct tmem_oid oid;
+ uint32_t index;
+ DECL_SENTINEL
+};
+
+struct flushlist_node {
+ struct ramster_remotify_hdr rem_op;
+ struct tmem_xhandle xh;
+};
+
+union {
+ struct ramster_remotify_hdr rem_op;
+ struct zv_hdr zv;
+ struct zbud_hdr zbud;
+ struct flushlist_node flist;
+} remotify_list_node;
+
+static LIST_HEAD(zcache_rem_op_list);
+static DEFINE_SPINLOCK(zcache_rem_op_list_lock);
+
+#if 0
+/* this is more aggressive but may cause other problems? */
+#define ZCACHE_GFP_MASK (GFP_ATOMIC | __GFP_NORETRY | __GFP_NOWARN)
+#else
+#define ZCACHE_GFP_MASK \
+ (__GFP_FS | __GFP_NORETRY | __GFP_NOWARN | __GFP_NOMEMALLOC)
+#endif
+
+#define MAX_POOLS_PER_CLIENT 16
+
+#define MAX_CLIENTS 16
+#define LOCAL_CLIENT ((uint16_t)-1)
+
+MODULE_LICENSE("GPL");
+
+struct zcache_client {
+ struct tmem_pool *tmem_pools[MAX_POOLS_PER_CLIENT];
+ struct xv_pool *xvpool;
+ bool allocated;
+ atomic_t refcount;
+};
+
+static struct zcache_client zcache_host;
+static struct zcache_client zcache_clients[MAX_CLIENTS];
+
+static inline uint16_t get_client_id_from_client(struct zcache_client *cli)
+{
+ BUG_ON(cli == NULL);
+ if (cli == &zcache_host)
+ return LOCAL_CLIENT;
+ return cli - &zcache_clients[0];
+}
+
+static inline bool is_local_client(struct zcache_client *cli)
+{
+ return cli == &zcache_host;
+}
+
+/**********
+ * Compression buddies ("zbud") provides for packing two (or, possibly
+ * in the future, more) compressed ephemeral pages into a single "raw"
+ * (physical) page and tracking them with data structures so that
+ * the raw pages can be easily reclaimed.
+ *
+ * A zbud page ("zbpg") is an aligned page containing a list_head,
+ * a lock, and two "zbud headers". The remainder of the physical
+ * page is divided up into aligned 64-byte "chunks" which contain
+ * the compressed data for zero, one, or two zbuds. Each zbpg
+ * resides on: (1) an "unused list" if it has no zbuds; (2) a
+ * "buddied" list if it is fully populated with two zbuds; or
+ * (3) one of PAGE_SIZE/64 "unbuddied" lists indexed by how many chunks
+ * the one unbuddied zbud uses. The data inside a zbpg cannot be
+ * read or written unless the zbpg's lock is held.
+ */
+
+struct zbud_page {
+ struct list_head bud_list;
+ spinlock_t lock;
+ struct zbud_hdr buddy[ZBUD_MAX_BUDS];
+ DECL_SENTINEL
+ /* followed by NUM_CHUNK aligned CHUNK_SIZE-byte chunks */
+};
+
+#define CHUNK_SHIFT 6
+#define CHUNK_SIZE (1 << CHUNK_SHIFT)
+#define CHUNK_MASK (~(CHUNK_SIZE-1))
+#define NCHUNKS (((PAGE_SIZE - sizeof(struct zbud_page)) & \
+ CHUNK_MASK) >> CHUNK_SHIFT)
+#define MAX_CHUNK (NCHUNKS-1)
+
+static struct {
+ struct list_head list;
+ unsigned count;
+} zbud_unbuddied[NCHUNKS];
+/* list N contains pages with N chunks USED and NCHUNKS-N unused */
+/* element 0 is never used but optimizing that isn't worth it */
+static unsigned long zbud_cumul_chunk_counts[NCHUNKS];
+
+struct list_head zbud_buddied_list;
+static unsigned long zcache_zbud_buddied_count;
+
+/* protects the buddied list and all unbuddied lists */
+static DEFINE_SPINLOCK(zbud_budlists_spinlock);
+
+static atomic_t zcache_zbud_curr_raw_pages;
+static atomic_t zcache_zbud_curr_zpages;
+static unsigned long zcache_zbud_curr_zbytes;
+static unsigned long zcache_zbud_cumul_zpages;
+static unsigned long zcache_zbud_cumul_zbytes;
+static unsigned long zcache_compress_poor;
+static unsigned long zcache_policy_percent_exceeded;
+static unsigned long zcache_mean_compress_poor;
+
+/*
+ * RAMster counters
+ * - Remote pages are pages with a local pampd but the data is remote
+ * - Foreign pages are pages stored locally but belonging to another node
+ */
+static atomic_t ramster_remote_pers_pages = ATOMIC_INIT(0);
+static unsigned long ramster_pers_remotify_enable;
+static unsigned long ramster_eph_remotify_enable;
+static unsigned long ramster_eph_pages_remoted;
+static unsigned long ramster_eph_pages_remote_failed;
+static unsigned long ramster_pers_pages_remoted;
+static unsigned long ramster_pers_pages_remote_failed;
+static unsigned long ramster_pers_pages_remote_nomem;
+static unsigned long ramster_remote_objects_flushed;
+static unsigned long ramster_remote_object_flushes_failed;
+static unsigned long ramster_remote_pages_flushed;
+static unsigned long ramster_remote_page_flushes_failed;
+static unsigned long ramster_remote_eph_pages_succ_get;
+static unsigned long ramster_remote_pers_pages_succ_get;
+static unsigned long ramster_remote_eph_pages_unsucc_get;
+static unsigned long ramster_remote_pers_pages_unsucc_get;
+static atomic_t ramster_curr_flnode_count = ATOMIC_INIT(0);
+static unsigned long ramster_curr_flnode_count_max;
+static atomic_t ramster_foreign_eph_pampd_count = ATOMIC_INIT(0);
+static unsigned long ramster_foreign_eph_pampd_count_max;
+static atomic_t ramster_foreign_pers_pampd_count = ATOMIC_INIT(0);
+static unsigned long ramster_foreign_pers_pampd_count_max;
+
+/* forward references */
+static void *zcache_get_free_page(void);
+static void zcache_free_page(void *p);
+
+/*
+ * zbud helper functions
+ */
+
+static inline unsigned zbud_max_buddy_size(void)
+{
+ return MAX_CHUNK << CHUNK_SHIFT;
+}
+
+static inline unsigned zbud_size_to_chunks(unsigned size)
+{
+ BUG_ON(size == 0 || size > zbud_max_buddy_size());
+ return (size + CHUNK_SIZE - 1) >> CHUNK_SHIFT;
+}
+
+static inline int zbud_budnum(struct zbud_hdr *zh)
+{
+ unsigned offset = (unsigned long)zh & (PAGE_SIZE - 1);
+ struct zbud_page *zbpg = NULL;
+ unsigned budnum = -1U;
+ int i;
+
+ for (i = 0; i < ZBUD_MAX_BUDS; i++)
+ if (offset == offsetof(typeof(*zbpg), buddy[i])) {
+ budnum = i;
+ break;
+ }
+ BUG_ON(budnum == -1U);
+ return budnum;
+}
+
+static char *zbud_data(struct zbud_hdr *zh, unsigned size)
+{
+ struct zbud_page *zbpg;
+ char *p;
+ unsigned budnum;
+
+ ASSERT_SENTINEL(zh, ZBH);
+ budnum = zbud_budnum(zh);
+ BUG_ON(size == 0 || size > zbud_max_buddy_size());
+ zbpg = container_of(zh, struct zbud_page, buddy[budnum]);
+ ASSERT_SPINLOCK(&zbpg->lock);
+ p = (char *)zbpg;
+ if (budnum == 0)
+ p += ((sizeof(struct zbud_page) + CHUNK_SIZE - 1) &
+ CHUNK_MASK);
+ else if (budnum == 1)
+ p += PAGE_SIZE - ((size + CHUNK_SIZE - 1) & CHUNK_MASK);
+ return p;
+}
+
+static void zbud_copy_from_pampd(char *data, size_t *size, struct zbud_hdr *zh)
+{
+ struct zbud_page *zbpg;
+ char *p;
+ unsigned budnum;
+
+ ASSERT_SENTINEL(zh, ZBH);
+ budnum = zbud_budnum(zh);
+ zbpg = container_of(zh, struct zbud_page, buddy[budnum]);
+ spin_lock(&zbpg->lock);
+ BUG_ON(zh->size > *size);
+ p = (char *)zbpg;
+ if (budnum == 0)
+ p += ((sizeof(struct zbud_page) + CHUNK_SIZE - 1) &
+ CHUNK_MASK);
+ else if (budnum == 1)
+ p += PAGE_SIZE - ((zh->size + CHUNK_SIZE - 1) & CHUNK_MASK);
+ /* client should be filled in by caller */
+ memcpy(data, p, zh->size);
+ *size = zh->size;
+ spin_unlock(&zbpg->lock);
+}
+
+/*
+ * zbud raw page management
+ */
+
+static struct zbud_page *zbud_alloc_raw_page(void)
+{
+ struct zbud_page *zbpg = NULL;
+ struct zbud_hdr *zh0, *zh1;
+ zbpg = zcache_get_free_page();
+ if (likely(zbpg != NULL)) {
+ INIT_LIST_HEAD(&zbpg->bud_list);
+ zh0 = &zbpg->buddy[0]; zh1 = &zbpg->buddy[1];
+ spin_lock_init(&zbpg->lock);
+ atomic_inc(&zcache_zbud_curr_raw_pages);
+ INIT_LIST_HEAD(&zbpg->bud_list);
+ SET_SENTINEL(zbpg, ZBPG);
+ zh0->size = 0; zh1->size = 0;
+ tmem_oid_set_invalid(&zh0->oid);
+ tmem_oid_set_invalid(&zh1->oid);
+ }
+ return zbpg;
+}
+
+static void zbud_free_raw_page(struct zbud_page *zbpg)
+{
+ struct zbud_hdr *zh0 = &zbpg->buddy[0], *zh1 = &zbpg->buddy[1];
+
+ ASSERT_SENTINEL(zbpg, ZBPG);
+ BUG_ON(!list_empty(&zbpg->bud_list));
+ ASSERT_SPINLOCK(&zbpg->lock);
+ BUG_ON(zh0->size != 0 || tmem_oid_valid(&zh0->oid));
+ BUG_ON(zh1->size != 0 || tmem_oid_valid(&zh1->oid));
+ INVERT_SENTINEL(zbpg, ZBPG);
+ spin_unlock(&zbpg->lock);
+ atomic_dec(&zcache_zbud_curr_raw_pages);
+ zcache_free_page(zbpg);
+}
+
+/*
+ * core zbud handling routines
+ */
+
+static unsigned zbud_free(struct zbud_hdr *zh)
+{
+ unsigned size;
+
+ ASSERT_SENTINEL(zh, ZBH);
+ BUG_ON(!tmem_oid_valid(&zh->oid));
+ size = zh->size;
+ BUG_ON(zh->size == 0 || zh->size > zbud_max_buddy_size());
+ zh->size = 0;
+ tmem_oid_set_invalid(&zh->oid);
+ INVERT_SENTINEL(zh, ZBH);
+ zcache_zbud_curr_zbytes -= size;
+ atomic_dec(&zcache_zbud_curr_zpages);
+ return size;
+}
+
+static void zbud_free_and_delist(struct zbud_hdr *zh)
+{
+ unsigned chunks;
+ struct zbud_hdr *zh_other;
+ unsigned budnum = zbud_budnum(zh), size;
+ struct zbud_page *zbpg =
+ container_of(zh, struct zbud_page, buddy[budnum]);
+
+ /* FIXME, should be BUG_ON, pool destruction path doesn't disable
+ * interrupts tmem_destroy_pool()->tmem_pampd_destroy_all_in_obj()->
+ * tmem_objnode_node_destroy()-> zcache_pampd_free() */
+ WARN_ON(!irqs_disabled());
+ spin_lock(&zbpg->lock);
+ if (list_empty(&zbpg->bud_list)) {
+ /* ignore zombie page... see zbud_evict_pages() */
+ spin_unlock(&zbpg->lock);
+ return;
+ }
+ size = zbud_free(zh);
+ ASSERT_SPINLOCK(&zbpg->lock);
+ zh_other = &zbpg->buddy[(budnum == 0) ? 1 : 0];
+ if (zh_other->size == 0) { /* was unbuddied: unlist and free */
+ chunks = zbud_size_to_chunks(size) ;
+ spin_lock(&zbud_budlists_spinlock);
+ BUG_ON(list_empty(&zbud_unbuddied[chunks].list));
+ list_del_init(&zbpg->bud_list);
+ zbud_unbuddied[chunks].count--;
+ spin_unlock(&zbud_budlists_spinlock);
+ zbud_free_raw_page(zbpg);
+ } else { /* was buddied: move remaining buddy to unbuddied list */
+ chunks = zbud_size_to_chunks(zh_other->size) ;
+ spin_lock(&zbud_budlists_spinlock);
+ list_del_init(&zbpg->bud_list);
+ zcache_zbud_buddied_count--;
+ list_add_tail(&zbpg->bud_list, &zbud_unbuddied[chunks].list);
+ zbud_unbuddied[chunks].count++;
+ spin_unlock(&zbud_budlists_spinlock);
+ spin_unlock(&zbpg->lock);
+ }
+}
+
+static struct zbud_hdr *zbud_create(uint16_t client_id, uint16_t pool_id,
+ struct tmem_oid *oid,
+ uint32_t index, struct page *page,
+ void *cdata, unsigned size)
+{
+ struct zbud_hdr *zh0, *zh1, *zh = NULL;
+ struct zbud_page *zbpg = NULL, *ztmp;
+ unsigned nchunks;
+ char *to;
+ int i, found_good_buddy = 0;
+
+ nchunks = zbud_size_to_chunks(size) ;
+ for (i = MAX_CHUNK - nchunks + 1; i > 0; i--) {
+ spin_lock(&zbud_budlists_spinlock);
+ if (!list_empty(&zbud_unbuddied[i].list)) {
+ list_for_each_entry_safe(zbpg, ztmp,
+ &zbud_unbuddied[i].list, bud_list) {
+ if (spin_trylock(&zbpg->lock)) {
+ found_good_buddy = i;
+ goto found_unbuddied;
+ }
+ }
+ }
+ spin_unlock(&zbud_budlists_spinlock);
+ }
+ /* didn't find a good buddy, try allocating a new page */
+ zbpg = zbud_alloc_raw_page();
+ if (unlikely(zbpg == NULL))
+ goto out;
+ /* ok, have a page, now compress the data before taking locks */
+ spin_lock(&zbud_budlists_spinlock);
+ spin_lock(&zbpg->lock);
+ list_add_tail(&zbpg->bud_list, &zbud_unbuddied[nchunks].list);
+ zbud_unbuddied[nchunks].count++;
+ zh = &zbpg->buddy[0];
+ goto init_zh;
+
+found_unbuddied:
+ ASSERT_SPINLOCK(&zbpg->lock);
+ zh0 = &zbpg->buddy[0]; zh1 = &zbpg->buddy[1];
+ BUG_ON(!((zh0->size == 0) ^ (zh1->size == 0)));
+ if (zh0->size != 0) { /* buddy0 in use, buddy1 is vacant */
+ ASSERT_SENTINEL(zh0, ZBH);
+ zh = zh1;
+ } else if (zh1->size != 0) { /* buddy1 in use, buddy0 is vacant */
+ ASSERT_SENTINEL(zh1, ZBH);
+ zh = zh0;
+ } else
+ BUG();
+ list_del_init(&zbpg->bud_list);
+ zbud_unbuddied[found_good_buddy].count--;
+ list_add_tail(&zbpg->bud_list, &zbud_buddied_list);
+ zcache_zbud_buddied_count++;
+
+init_zh:
+ SET_SENTINEL(zh, ZBH);
+ zh->size = size;
+ zh->index = index;
+ zh->oid = *oid;
+ zh->pool_id = pool_id;
+ zh->client_id = client_id;
+ to = zbud_data(zh, size);
+ memcpy(to, cdata, size);
+ spin_unlock(&zbpg->lock);
+ spin_unlock(&zbud_budlists_spinlock);
+ zbud_cumul_chunk_counts[nchunks]++;
+ atomic_inc(&zcache_zbud_curr_zpages);
+ zcache_zbud_cumul_zpages++;
+ zcache_zbud_curr_zbytes += size;
+ zcache_zbud_cumul_zbytes += size;
+out:
+ return zh;
+}
+
+static int zbud_decompress(struct page *page, struct zbud_hdr *zh)
+{
+ struct zbud_page *zbpg;
+ unsigned budnum = zbud_budnum(zh);
+ size_t out_len = PAGE_SIZE;
+ char *to_va, *from_va;
+ unsigned size;
+ int ret = 0;
+
+ zbpg = container_of(zh, struct zbud_page, buddy[budnum]);
+ spin_lock(&zbpg->lock);
+ if (list_empty(&zbpg->bud_list)) {
+ /* ignore zombie page... see zbud_evict_pages() */
+ ret = -EINVAL;
+ goto out;
+ }
+ ASSERT_SENTINEL(zh, ZBH);
+ BUG_ON(zh->size == 0 || zh->size > zbud_max_buddy_size());
- to_va = kmap_atomic(page, KM_USER0);
++ to_va = kmap_atomic(page);
+ size = zh->size;
+ from_va = zbud_data(zh, size);
+ ret = lzo1x_decompress_safe(from_va, size, to_va, &out_len);
+ BUG_ON(ret != LZO_E_OK);
+ BUG_ON(out_len != PAGE_SIZE);
- kunmap_atomic(to_va, KM_USER0);
++ kunmap_atomic(to_va);
+out:
+ spin_unlock(&zbpg->lock);
+ return ret;
+}
+
+/*
+ * The following routines handle shrinking of ephemeral pages by evicting
+ * pages "least valuable" first.
+ */
+
+static unsigned long zcache_evicted_raw_pages;
+static unsigned long zcache_evicted_buddied_pages;
+static unsigned long zcache_evicted_unbuddied_pages;
+
+static struct tmem_pool *zcache_get_pool_by_id(uint16_t cli_id,
+ uint16_t poolid);
+static void zcache_put_pool(struct tmem_pool *pool);
+
+/*
+ * Flush and free all zbuds in a zbpg, then free the pageframe
+ */
+static void zbud_evict_zbpg(struct zbud_page *zbpg)
+{
+ struct zbud_hdr *zh;
+ int i, j;
+ uint32_t pool_id[ZBUD_MAX_BUDS], client_id[ZBUD_MAX_BUDS];
+ uint32_t index[ZBUD_MAX_BUDS];
+ struct tmem_oid oid[ZBUD_MAX_BUDS];
+ struct tmem_pool *pool;
+ unsigned long flags;
+
+ ASSERT_SPINLOCK(&zbpg->lock);
+ for (i = 0, j = 0; i < ZBUD_MAX_BUDS; i++) {
+ zh = &zbpg->buddy[i];
+ if (zh->size) {
+ client_id[j] = zh->client_id;
+ pool_id[j] = zh->pool_id;
+ oid[j] = zh->oid;
+ index[j] = zh->index;
+ j++;
+ }
+ }
+ spin_unlock(&zbpg->lock);
+ for (i = 0; i < j; i++) {
+ pool = zcache_get_pool_by_id(client_id[i], pool_id[i]);
+ BUG_ON(pool == NULL);
+ local_irq_save(flags);
+ /* these flushes should dispose of any local storage */
+ tmem_flush_page(pool, &oid[i], index[i]);
+ local_irq_restore(flags);
+ zcache_put_pool(pool);
+ }
+}
+
+/*
+ * Free nr pages. This code is funky because we want to hold the locks
+ * protecting various lists for as short a time as possible, and in some
+ * circumstances the list may change asynchronously when the list lock is
+ * not held. In some cases we also trylock not only to avoid waiting on a
+ * page in use by another cpu, but also to avoid potential deadlock due to
+ * lock inversion.
+ */
+static void zbud_evict_pages(int nr)
+{
+ struct zbud_page *zbpg;
+ int i, newly_unused_pages = 0;
+
+
+ /* now try freeing unbuddied pages, starting with least space avail */
+ for (i = 0; i < MAX_CHUNK; i++) {
+retry_unbud_list_i:
+ spin_lock_bh(&zbud_budlists_spinlock);
+ if (list_empty(&zbud_unbuddied[i].list)) {
+ spin_unlock_bh(&zbud_budlists_spinlock);
+ continue;
+ }
+ list_for_each_entry(zbpg, &zbud_unbuddied[i].list, bud_list) {
+ if (unlikely(!spin_trylock(&zbpg->lock)))
+ continue;
+ zbud_unbuddied[i].count--;
+ spin_unlock(&zbud_budlists_spinlock);
+ zcache_evicted_unbuddied_pages++;
+ /* want budlists unlocked when doing zbpg eviction */
+ zbud_evict_zbpg(zbpg);
+ newly_unused_pages++;
+ local_bh_enable();
+ if (--nr <= 0)
+ goto evict_unused;
+ goto retry_unbud_list_i;
+ }
+ spin_unlock_bh(&zbud_budlists_spinlock);
+ }
+
+ /* as a last resort, free buddied pages */
+retry_bud_list:
+ spin_lock_bh(&zbud_budlists_spinlock);
+ if (list_empty(&zbud_buddied_list)) {
+ spin_unlock_bh(&zbud_budlists_spinlock);
+ goto evict_unused;
+ }
+ list_for_each_entry(zbpg, &zbud_buddied_list, bud_list) {
+ if (unlikely(!spin_trylock(&zbpg->lock)))
+ continue;
+ zcache_zbud_buddied_count--;
+ spin_unlock(&zbud_budlists_spinlock);
+ zcache_evicted_buddied_pages++;
+ /* want budlists unlocked when doing zbpg eviction */
+ zbud_evict_zbpg(zbpg);
+ newly_unused_pages++;
+ local_bh_enable();
+ if (--nr <= 0)
+ goto evict_unused;
+ goto retry_bud_list;
+ }
+ spin_unlock_bh(&zbud_budlists_spinlock);
+
+evict_unused:
+ return;
+}
+
+static DEFINE_PER_CPU(unsigned char *, zcache_remoteputmem);
+
+static int zbud_remotify_zbud(struct tmem_xhandle *xh, char *data,
+ size_t size)
+{
+ struct tmem_pool *pool;
+ int i, remotenode, ret = -1;
+ unsigned char cksum, *p;
+ unsigned long flags;
+
+ for (p = data, cksum = 0, i = 0; i < size; i++)
+ cksum += *p;
+ ret = ramster_remote_put(xh, data, size, true, &remotenode);
+ if (ret == 0) {
+ /* data was successfully remoted so change the local version
+ * to point to the remote node where it landed */
+ pool = zcache_get_pool_by_id(LOCAL_CLIENT, xh->pool_id);
+ BUG_ON(pool == NULL);
+ local_irq_save(flags);
+ /* tmem_replace will also free up any local space */
+ (void)tmem_replace(pool, &xh->oid, xh->index,
+ pampd_make_remote(remotenode, size, cksum));
+ local_irq_restore(flags);
+ zcache_put_pool(pool);
+ ramster_eph_pages_remoted++;
+ ret = 0;
+ } else
+ ramster_eph_pages_remote_failed++;
+ return ret;
+}
+
+static int zbud_remotify_zbpg(struct zbud_page *zbpg)
+{
+ struct zbud_hdr *zh1, *zh2 = NULL;
+ struct tmem_xhandle xh1, xh2 = { 0 };
+ char *data1 = NULL, *data2 = NULL;
+ size_t size1 = 0, size2 = 0;
+ int ret = 0;
+ unsigned char *tmpmem = __get_cpu_var(zcache_remoteputmem);
+
+ ASSERT_SPINLOCK(&zbpg->lock);
+ if (zbpg->buddy[0].size == 0)
+ zh1 = &zbpg->buddy[1];
+ else if (zbpg->buddy[1].size == 0)
+ zh1 = &zbpg->buddy[0];
+ else {
+ zh1 = &zbpg->buddy[0];
+ zh2 = &zbpg->buddy[1];
+ }
+ /* don't remotify pages that are already remotified */
+ if (zh1->client_id != LOCAL_CLIENT)
+ zh1 = NULL;
+ if ((zh2 != NULL) && (zh2->client_id != LOCAL_CLIENT))
+ zh2 = NULL;
+
+ /* copy the data and metadata so can release lock */
+ if (zh1 != NULL) {
+ xh1.client_id = zh1->client_id;
+ xh1.pool_id = zh1->pool_id;
+ xh1.oid = zh1->oid;
+ xh1.index = zh1->index;
+ size1 = zh1->size;
+ data1 = zbud_data(zh1, size1);
+ memcpy(tmpmem, zbud_data(zh1, size1), size1);
+ data1 = tmpmem;
+ tmpmem += size1;
+ }
+ if (zh2 != NULL) {
+ xh2.client_id = zh2->client_id;
+ xh2.pool_id = zh2->pool_id;
+ xh2.oid = zh2->oid;
+ xh2.index = zh2->index;
+ size2 = zh2->size;
+ memcpy(tmpmem, zbud_data(zh2, size2), size2);
+ data2 = tmpmem;
+ }
+ spin_unlock(&zbpg->lock);
+ preempt_enable();
+
+ /* OK, no locks held anymore, remotify one or both zbuds */
+ if (zh1 != NULL)
+ ret = zbud_remotify_zbud(&xh1, data1, size1);
+ if (zh2 != NULL)
+ ret |= zbud_remotify_zbud(&xh2, data2, size2);
+ return ret;
+}
+
+void zbud_remotify_pages(int nr)
+{
+ struct zbud_page *zbpg;
+ int i, ret;
+
+ /*
+ * for now just try remotifying unbuddied pages, starting with
+ * least space avail
+ */
+ for (i = 0; i < MAX_CHUNK; i++) {
+retry_unbud_list_i:
+ preempt_disable(); /* enable in zbud_remotify_zbpg */
+ spin_lock_bh(&zbud_budlists_spinlock);
+ if (list_empty(&zbud_unbuddied[i].list)) {
+ spin_unlock_bh(&zbud_budlists_spinlock);
+ preempt_enable();
+ continue; /* next i in for loop */
+ }
+ list_for_each_entry(zbpg, &zbud_unbuddied[i].list, bud_list) {
+ if (unlikely(!spin_trylock(&zbpg->lock)))
+ continue; /* next list_for_each_entry */
+ zbud_unbuddied[i].count--;
+ /* want budlists unlocked when doing zbpg remotify */
+ spin_unlock_bh(&zbud_budlists_spinlock);
+ ret = zbud_remotify_zbpg(zbpg);
+ /* preemption is re-enabled in zbud_remotify_zbpg */
+ if (ret == 0) {
+ if (--nr <= 0)
+ goto out;
+ goto retry_unbud_list_i;
+ }
+ /* if fail to remotify any page, quit */
+ pr_err("TESTING zbud_remotify_pages failed on page,"
+ " trying to re-add\n");
+ spin_lock_bh(&zbud_budlists_spinlock);
+ spin_lock(&zbpg->lock);
+ list_add_tail(&zbpg->bud_list, &zbud_unbuddied[i].list);
+ zbud_unbuddied[i].count++;
+ spin_unlock(&zbpg->lock);
+ spin_unlock_bh(&zbud_budlists_spinlock);
+ pr_err("TESTING zbud_remotify_pages failed on page,"
+ " finished re-add\n");
+ goto out;
+ }
+ spin_unlock_bh(&zbud_budlists_spinlock);
+ preempt_enable();
+ }
+
+next_buddied_zbpg:
+ preempt_disable(); /* enable in zbud_remotify_zbpg */
+ spin_lock_bh(&zbud_budlists_spinlock);
+ if (list_empty(&zbud_buddied_list))
+ goto unlock_out;
+ list_for_each_entry(zbpg, &zbud_buddied_list, bud_list) {
+ if (unlikely(!spin_trylock(&zbpg->lock)))
+ continue; /* next list_for_each_entry */
+ zcache_zbud_buddied_count--;
+ /* want budlists unlocked when doing zbpg remotify */
+ spin_unlock_bh(&zbud_budlists_spinlock);
+ ret = zbud_remotify_zbpg(zbpg);
+ /* preemption is re-enabled in zbud_remotify_zbpg */
+ if (ret == 0) {
+ if (--nr <= 0)
+ goto out;
+ goto next_buddied_zbpg;
+ }
+ /* if fail to remotify any page, quit */
+ pr_err("TESTING zbud_remotify_pages failed on BUDDIED page,"
+ " trying to re-add\n");
+ spin_lock_bh(&zbud_budlists_spinlock);
+ spin_lock(&zbpg->lock);
+ list_add_tail(&zbpg->bud_list, &zbud_buddied_list);
+ zcache_zbud_buddied_count++;
+ spin_unlock(&zbpg->lock);
+ spin_unlock_bh(&zbud_budlists_spinlock);
+ pr_err("TESTING zbud_remotify_pages failed on BUDDIED page,"
+ " finished re-add\n");
+ goto out;
+ }
+unlock_out:
+ spin_unlock_bh(&zbud_budlists_spinlock);
+ preempt_enable();
+out:
+ return;
+}
+
+/* the "flush list" asynchronously collects pages to remotely flush */
+#define FLUSH_ENTIRE_OBJECT ((uint32_t)-1)
+static void ramster_flnode_free(struct flushlist_node *,
+ struct tmem_pool *);
+
+static void zcache_remote_flush_page(struct flushlist_node *flnode)
+{
+ struct tmem_xhandle *xh;
+ int remotenode, ret;
+
+ preempt_disable();
+ xh = &flnode->xh;
+ remotenode = flnode->xh.client_id;
+ ret = ramster_remote_flush(xh, remotenode);
+ if (ret >= 0)
+ ramster_remote_pages_flushed++;
+ else
+ ramster_remote_page_flushes_failed++;
+ preempt_enable_no_resched();
+ ramster_flnode_free(flnode, NULL);
+}
+
+static void zcache_remote_flush_object(struct flushlist_node *flnode)
+{
+ struct tmem_xhandle *xh;
+ int remotenode, ret;
+
+ preempt_disable();
+ xh = &flnode->xh;
+ remotenode = flnode->xh.client_id;
+ ret = ramster_remote_flush_object(xh, remotenode);
+ if (ret >= 0)
+ ramster_remote_objects_flushed++;
+ else
+ ramster_remote_object_flushes_failed++;
+ preempt_enable_no_resched();
+ ramster_flnode_free(flnode, NULL);
+}
+
+static void zcache_remote_eph_put(struct zbud_hdr *zbud)
+{
+ /* FIXME */
+}
+
+static void zcache_remote_pers_put(struct zv_hdr *zv)
+{
+ struct tmem_xhandle xh;
+ uint16_t size;
+ bool ephemeral;
+ int remotenode, ret = -1;
+ char *data;
+ struct tmem_pool *pool;
+ unsigned long flags;
+ unsigned char cksum;
+ char *p;
+ int i;
+ unsigned char *tmpmem = __get_cpu_var(zcache_remoteputmem);
+
+ ASSERT_SENTINEL(zv, ZVH);
+ BUG_ON(zv->client_id != LOCAL_CLIENT);
+ local_bh_disable();
+ xh.client_id = zv->client_id;
+ xh.pool_id = zv->pool_id;
+ xh.oid = zv->oid;
+ xh.index = zv->index;
+ size = xv_get_object_size(zv) - sizeof(*zv);
+ BUG_ON(size == 0 || size > zv_max_page_size);
+ data = (char *)zv + sizeof(*zv);
+ for (p = data, cksum = 0, i = 0; i < size; i++)
+ cksum += *p;
+ memcpy(tmpmem, data, size);
+ data = tmpmem;
+ pool = zcache_get_pool_by_id(zv->client_id, zv->pool_id);
+ ephemeral = is_ephemeral(pool);
+ zcache_put_pool(pool);
+ /* now OK to release lock set in caller */
+ spin_unlock(&zcache_rem_op_list_lock);
+ local_bh_enable();
+ preempt_disable();
+ ret = ramster_remote_put(&xh, data, size, ephemeral, &remotenode);
+ preempt_enable_no_resched();
+ if (ret != 0) {
+ /*
+ * This is some form of a memory leak... if the remote put
+ * fails, there will never be another attempt to remotify
+ * this page. But since we've dropped the zv pointer,
+ * the page may have been freed or the data replaced
+ * so we can't just "put it back" in the remote op list.
+ * Even if we could, not sure where to put it in the list
+ * because there may be flushes that must be strictly
+ * ordered vs the put. So leave this as a FIXME for now.
+ * But count them so we know if it becomes a problem.
+ */
+ ramster_pers_pages_remote_failed++;
+ goto out;
+ } else
+ atomic_inc(&ramster_remote_pers_pages);
+ ramster_pers_pages_remoted++;
+ /*
+ * data was successfully remoted so change the local version to
+ * point to the remote node where it landed
+ */
+ local_bh_disable();
+ pool = zcache_get_pool_by_id(LOCAL_CLIENT, xh.pool_id);
+ local_irq_save(flags);
+ (void)tmem_replace(pool, &xh.oid, xh.index,
+ pampd_make_remote(remotenode, size, cksum));
+ local_irq_restore(flags);
+ zcache_put_pool(pool);
+ local_bh_enable();
+out:
+ return;
+}
+
+static void zcache_do_remotify_ops(int nr)
+{
+ struct ramster_remotify_hdr *rem_op;
+ union remotify_list_node *u;
+
+ while (1) {
+ if (!nr)
+ goto out;
+ spin_lock(&zcache_rem_op_list_lock);
+ if (list_empty(&zcache_rem_op_list)) {
+ spin_unlock(&zcache_rem_op_list_lock);
+ goto out;
+ }
+ rem_op = list_first_entry(&zcache_rem_op_list,
+ struct ramster_remotify_hdr, list);
+ list_del_init(&rem_op->list);
+ if (rem_op->op != RAMSTER_REMOTIFY_PERS_PUT)
+ spin_unlock(&zcache_rem_op_list_lock);
+ u = (union remotify_list_node *)rem_op;
+ switch (rem_op->op) {
+ case RAMSTER_REMOTIFY_EPH_PUT:
+BUG();
+ zcache_remote_eph_put((struct zbud_hdr *)rem_op);
+ break;
+ case RAMSTER_REMOTIFY_PERS_PUT:
+ zcache_remote_pers_put((struct zv_hdr *)rem_op);
+ break;
+ case RAMSTER_REMOTIFY_FLUSH_PAGE:
+ zcache_remote_flush_page((struct flushlist_node *)u);
+ break;
+ case RAMSTER_REMOTIFY_FLUSH_OBJ:
+ zcache_remote_flush_object((struct flushlist_node *)u);
+ break;
+ default:
+ BUG();
+ }
+ }
+out:
+ return;
+}
+
+/*
+ * Communicate interface revision with userspace
+ */
+#include "cluster/ramster_nodemanager.h"
+static unsigned long ramster_interface_revision = R2NM_API_VERSION;
+
+/*
+ * For now, just push over a few pages every few seconds to
+ * ensure that it basically works
+ */
+static struct workqueue_struct *ramster_remotify_workqueue;
+static void ramster_remotify_process(struct work_struct *work);
+static DECLARE_DELAYED_WORK(ramster_remotify_worker,
+ ramster_remotify_process);
+
+static void ramster_remotify_queue_delayed_work(unsigned long delay)
+{
+ if (!queue_delayed_work(ramster_remotify_workqueue,
+ &ramster_remotify_worker, delay))
+ pr_err("ramster_remotify: bad workqueue\n");
+}
+
+
+static int use_frontswap;
+static int use_cleancache;
+static int ramster_remote_target_nodenum = -1;
+static void ramster_remotify_process(struct work_struct *work)
+{
+ static bool remotify_in_progress;
+
+ BUG_ON(irqs_disabled());
+ if (remotify_in_progress)
+ ramster_remotify_queue_delayed_work(HZ);
+ else if (ramster_remote_target_nodenum != -1) {
+ remotify_in_progress = true;
+#ifdef CONFIG_CLEANCACHE
+ if (use_cleancache && ramster_eph_remotify_enable)
+ zbud_remotify_pages(5000); /* FIXME is this a good number? */
+#endif
+#ifdef CONFIG_FRONTSWAP
+ if (use_frontswap && ramster_pers_remotify_enable)
+ zcache_do_remotify_ops(500); /* FIXME is this a good number? */
+#endif
+ remotify_in_progress = false;
+ ramster_remotify_queue_delayed_work(HZ);
+ }
+}
+
+static void ramster_remotify_init(void)
+{
+ unsigned long n = 60UL;
+ ramster_remotify_workqueue =
+ create_singlethread_workqueue("ramster_remotify");
+ ramster_remotify_queue_delayed_work(n * HZ);
+}
+
+
+static void zbud_init(void)
+{
+ int i;
+
+ INIT_LIST_HEAD(&zbud_buddied_list);
+ zcache_zbud_buddied_count = 0;
+ for (i = 0; i < NCHUNKS; i++) {
+ INIT_LIST_HEAD(&zbud_unbuddied[i].list);
+ zbud_unbuddied[i].count = 0;
+ }
+}
+
+#ifdef CONFIG_SYSFS
+/*
+ * These sysfs routines show a nice distribution of how many zbpg's are
+ * currently (and have ever been placed) in each unbuddied list. It's fun
+ * to watch but can probably go away before final merge.
+ */
+static int zbud_show_unbuddied_list_counts(char *buf)
+{
+ int i;
+ char *p = buf;
+
+ for (i = 0; i < NCHUNKS; i++)
+ p += sprintf(p, "%u ", zbud_unbuddied[i].count);
+ return p - buf;
+}
+
+static int zbud_show_cumul_chunk_counts(char *buf)
+{
+ unsigned long i, chunks = 0, total_chunks = 0, sum_total_chunks = 0;
+ unsigned long total_chunks_lte_21 = 0, total_chunks_lte_32 = 0;
+ unsigned long total_chunks_lte_42 = 0;
+ char *p = buf;
+
+ for (i = 0; i < NCHUNKS; i++) {
+ p += sprintf(p, "%lu ", zbud_cumul_chunk_counts[i]);
+ chunks += zbud_cumul_chunk_counts[i];
+ total_chunks += zbud_cumul_chunk_counts[i];
+ sum_total_chunks += i * zbud_cumul_chunk_counts[i];
+ if (i == 21)
+ total_chunks_lte_21 = total_chunks;
+ if (i == 32)
+ total_chunks_lte_32 = total_chunks;
+ if (i == 42)
+ total_chunks_lte_42 = total_chunks;
+ }
+ p += sprintf(p, "<=21:%lu <=32:%lu <=42:%lu, mean:%lu\n",
+ total_chunks_lte_21, total_chunks_lte_32, total_chunks_lte_42,
+ chunks == 0 ? 0 : sum_total_chunks / chunks);
+ return p - buf;
+}
+#endif
+
+/**********
+ * This "zv" PAM implementation combines the TLSF-based xvMalloc
+ * with lzo1x compression to maximize the amount of data that can
+ * be packed into a physical page.
+ *
+ * Zv represents a PAM page with the index and object (plus a "size" value
+ * necessary for decompression) immediately preceding the compressed data.
+ */
+
+/* rudimentary policy limits */
+/* total number of persistent pages may not exceed this percentage */
+static unsigned int zv_page_count_policy_percent = 75;
+/*
+ * byte count defining poor compression; pages with greater zsize will be
+ * rejected
+ */
+static unsigned int zv_max_zsize = (PAGE_SIZE / 8) * 7;
+/*
+ * byte count defining poor *mean* compression; pages with greater zsize
+ * will be rejected until sufficient better-compressed pages are accepted
+ * driving the mean below this threshold
+ */
+static unsigned int zv_max_mean_zsize = (PAGE_SIZE / 8) * 5;
+
+static atomic_t zv_curr_dist_counts[NCHUNKS];
+static atomic_t zv_cumul_dist_counts[NCHUNKS];
+
+
+static struct zv_hdr *zv_create(struct zcache_client *cli, uint32_t pool_id,
+ struct tmem_oid *oid, uint32_t index,
+ void *cdata, unsigned clen)
+{
+ struct page *page;
+ struct zv_hdr *zv = NULL;
+ uint32_t offset;
+ int alloc_size = clen + sizeof(struct zv_hdr);
+ int chunks = (alloc_size + (CHUNK_SIZE - 1)) >> CHUNK_SHIFT;
+ int ret;
+
+ BUG_ON(!irqs_disabled());
+ BUG_ON(chunks >= NCHUNKS);
+ ret = xv_malloc(cli->xvpool, clen + sizeof(struct zv_hdr),
+ &page, &offset, ZCACHE_GFP_MASK);
+ if (unlikely(ret))
+ goto out;
+ atomic_inc(&zv_curr_dist_counts[chunks]);
+ atomic_inc(&zv_cumul_dist_counts[chunks]);
- zv = kmap_atomic(page, KM_USER0) + offset;
++ zv = kmap_atomic(page) + offset;
+ zv->index = index;
+ zv->oid = *oid;
+ zv->pool_id = pool_id;
+ SET_SENTINEL(zv, ZVH);
+ INIT_LIST_HEAD(&zv->rem_op.list);
+ zv->client_id = get_client_id_from_client(cli);
+ zv->rem_op.op = RAMSTER_REMOTIFY_PERS_PUT;
+ if (zv->client_id == LOCAL_CLIENT) {
+ spin_lock(&zcache_rem_op_list_lock);
+ list_add_tail(&zv->rem_op.list, &zcache_rem_op_list);
+ spin_unlock(&zcache_rem_op_list_lock);
+ }
+ memcpy((char *)zv + sizeof(struct zv_hdr), cdata, clen);
- kunmap_atomic(zv, KM_USER0);
++ kunmap_atomic(zv);
+out:
+ return zv;
+}
+
+/* similar to zv_create, but just reserve space, no data yet */
+static struct zv_hdr *zv_alloc(struct tmem_pool *pool,
+ struct tmem_oid *oid, uint32_t index,
+ unsigned clen)
+{
+ struct zcache_client *cli = pool->client;
+ struct page *page;
+ struct zv_hdr *zv = NULL;
+ uint32_t offset;
+ int ret;
+
+ BUG_ON(!irqs_disabled());
+ BUG_ON(!is_local_client(pool->client));
+ ret = xv_malloc(cli->xvpool, clen + sizeof(struct zv_hdr),
+ &page, &offset, ZCACHE_GFP_MASK);
+ if (unlikely(ret))
+ goto out;
- zv = kmap_atomic(page, KM_USER0) + offset;
++ zv = kmap_atomic(page) + offset;
+ SET_SENTINEL(zv, ZVH);
+ INIT_LIST_HEAD(&zv->rem_op.list);
+ zv->client_id = LOCAL_CLIENT;
+ zv->rem_op.op = RAMSTER_INTRANSIT_PERS;
+ zv->index = index;
+ zv->oid = *oid;
+ zv->pool_id = pool->pool_id;
- kunmap_atomic(zv, KM_USER0);
++ kunmap_atomic(zv);
+out:
+ return zv;
+}
+
+static void zv_free(struct xv_pool *xvpool, struct zv_hdr *zv)
+{
+ unsigned long flags;
+ struct page *page;
+ uint32_t offset;
+ uint16_t size = xv_get_object_size(zv);
+ int chunks = (size + (CHUNK_SIZE - 1)) >> CHUNK_SHIFT;
+
+ ASSERT_SENTINEL(zv, ZVH);
+ BUG_ON(chunks >= NCHUNKS);
+ atomic_dec(&zv_curr_dist_counts[chunks]);
+ size -= sizeof(*zv);
+ spin_lock(&zcache_rem_op_list_lock);
+ size = xv_get_object_size(zv) - sizeof(*zv);
+ BUG_ON(size == 0);
+ INVERT_SENTINEL(zv, ZVH);
+ if (!list_empty(&zv->rem_op.list))
+ list_del_init(&zv->rem_op.list);
+ spin_unlock(&zcache_rem_op_list_lock);
+ page = virt_to_page(zv);
+ offset = (unsigned long)zv & ~PAGE_MASK;
+ local_irq_save(flags);
+ xv_free(xvpool, page, offset);
+ local_irq_restore(flags);
+}
+
+static void zv_decompress(struct page *page, struct zv_hdr *zv)
+{
+ size_t clen = PAGE_SIZE;
+ char *to_va;
+ unsigned size;
+ int ret;
+
+ ASSERT_SENTINEL(zv, ZVH);
+ size = xv_get_object_size(zv) - sizeof(*zv);
+ BUG_ON(size == 0);
- to_va = kmap_atomic(page, KM_USER0);
++ to_va = kmap_atomic(page);
+ ret = lzo1x_decompress_safe((char *)zv + sizeof(*zv),
+ size, to_va, &clen);
- kunmap_atomic(to_va, KM_USER0);
++ kunmap_atomic(to_va);
+ BUG_ON(ret != LZO_E_OK);
+ BUG_ON(clen != PAGE_SIZE);
+}
+
+static void zv_copy_from_pampd(char *data, size_t *bufsize, struct zv_hdr *zv)
+{
+ unsigned size;
+
+ ASSERT_SENTINEL(zv, ZVH);
+ size = xv_get_object_size(zv) - sizeof(*zv);
+ BUG_ON(size == 0 || size > zv_max_page_size);
+ BUG_ON(size > *bufsize);
+ memcpy(data, (char *)zv + sizeof(*zv), size);
+ *bufsize = size;
+}
+
+static void zv_copy_to_pampd(struct zv_hdr *zv, char *data, size_t size)
+{
+ unsigned zv_size;
+
+ ASSERT_SENTINEL(zv, ZVH);
+ zv_size = xv_get_object_size(zv) - sizeof(*zv);
+ BUG_ON(zv_size != size);
+ BUG_ON(zv_size == 0 || zv_size > zv_max_page_size);
+ memcpy((char *)zv + sizeof(*zv), data, size);
+}
+
+#ifdef CONFIG_SYSFS
+/*
+ * show a distribution of compression stats for zv pages.
+ */
+
+static int zv_curr_dist_counts_show(char *buf)
+{
+ unsigned long i, n, chunks = 0, sum_total_chunks = 0;
+ char *p = buf;
+
+ for (i = 0; i < NCHUNKS; i++) {
+ n = atomic_read(&zv_curr_dist_counts[i]);
+ p += sprintf(p, "%lu ", n);
+ chunks += n;
+ sum_total_chunks += i * n;
+ }
+ p += sprintf(p, "mean:%lu\n",
+ chunks == 0 ? 0 : sum_total_chunks / chunks);
+ return p - buf;
+}
+
+static int zv_cumul_dist_counts_show(char *buf)
+{
+ unsigned long i, n, chunks = 0, sum_total_chunks = 0;
+ char *p = buf;
+
+ for (i = 0; i < NCHUNKS; i++) {
+ n = atomic_read(&zv_cumul_dist_counts[i]);
+ p += sprintf(p, "%lu ", n);
+ chunks += n;
+ sum_total_chunks += i * n;
+ }
+ p += sprintf(p, "mean:%lu\n",
+ chunks == 0 ? 0 : sum_total_chunks / chunks);
+ return p - buf;
+}
+
+/*
+ * setting zv_max_zsize via sysfs causes all persistent (e.g. swap)
+ * pages that don't compress to less than this value (including metadata
+ * overhead) to be rejected. We don't allow the value to get too close
+ * to PAGE_SIZE.
+ */
+static ssize_t zv_max_zsize_show(struct kobject *kobj,
+ struct kobj_attribute *attr,
+ char *buf)
+{
+ return sprintf(buf, "%u\n", zv_max_zsize);
+}
+
+static ssize_t zv_max_zsize_store(struct kobject *kobj,
+ struct kobj_attribute *attr,
+ const char *buf, size_t count)
+{
+ unsigned long val;
+ int err;
+
+ if (!capable(CAP_SYS_ADMIN))
+ return -EPERM;
+
+ err = kstrtoul(buf, 10, &val);
+ if (err || (val == 0) || (val > (PAGE_SIZE / 8) * 7))
+ return -EINVAL;
+ zv_max_zsize = val;
+ return count;
+}
+
+/*
+ * setting zv_max_mean_zsize via sysfs causes all persistent (e.g. swap)
+ * pages that don't compress to less than this value (including metadata
+ * overhead) to be rejected UNLESS the mean compression is also smaller
+ * than this value. In other words, we are load-balancing-by-zsize the
+ * accepted pages. Again, we don't allow the value to get too close
+ * to PAGE_SIZE.
+ */
+static ssize_t zv_max_mean_zsize_show(struct kobject *kobj,
+ struct kobj_attribute *attr,
+ char *buf)
+{
+ return sprintf(buf, "%u\n", zv_max_mean_zsize);
+}
+
+static ssize_t zv_max_mean_zsize_store(struct kobject *kobj,
+ struct kobj_attribute *attr,
+ const char *buf, size_t count)
+{
+ unsigned long val;
+ int err;
+
+ if (!capable(CAP_SYS_ADMIN))
+ return -EPERM;
+
+ err = kstrtoul(buf, 10, &val);
+ if (err || (val == 0) || (val > (PAGE_SIZE / 8) * 7))
+ return -EINVAL;
+ zv_max_mean_zsize = val;
+ return count;
+}
+
+/*
+ * setting zv_page_count_policy_percent via sysfs sets an upper bound of
+ * persistent (e.g. swap) pages that will be retained according to:
+ * (zv_page_count_policy_percent * totalram_pages) / 100)
+ * when that limit is reached, further puts will be rejected (until
+ * some pages have been flushed). Note that, due to compression,
+ * this number may exceed 100; it defaults to 75 and we set an
+ * arbitary limit of 150. A poor choice will almost certainly result
+ * in OOM's, so this value should only be changed prudently.
+ */
+static ssize_t zv_page_count_policy_percent_show(struct kobject *kobj,
+ struct kobj_attribute *attr,
+ char *buf)
+{
+ return sprintf(buf, "%u\n", zv_page_count_policy_percent);
+}
+
+static ssize_t zv_page_count_policy_percent_store(struct kobject *kobj,
+ struct kobj_attribute *attr,
+ const char *buf, size_t count)
+{
+ unsigned long val;
+ int err;
+
+ if (!capable(CAP_SYS_ADMIN))
+ return -EPERM;
+
+ err = kstrtoul(buf, 10, &val);
+ if (err || (val == 0) || (val > 150))
+ return -EINVAL;
+ zv_page_count_policy_percent = val;
+ return count;
+}
+
+static struct kobj_attribute zcache_zv_max_zsize_attr = {
+ .attr = { .name = "zv_max_zsize", .mode = 0644 },
+ .show = zv_max_zsize_show,
+ .store = zv_max_zsize_store,
+};
+
+static struct kobj_attribute zcache_zv_max_mean_zsize_attr = {
+ .attr = { .name = "zv_max_mean_zsize", .mode = 0644 },
+ .show = zv_max_mean_zsize_show,
+ .store = zv_max_mean_zsize_store,
+};
+
+static struct kobj_attribute zcache_zv_page_count_policy_percent_attr = {
+ .attr = { .name = "zv_page_count_policy_percent",
+ .mode = 0644 },
+ .show = zv_page_count_policy_percent_show,
+ .store = zv_page_count_policy_percent_store,
+};
+#endif
+
+/*
+ * zcache core code starts here
+ */
+
+/* useful stats not collected by cleancache or frontswap */
+static unsigned long zcache_flush_total;
+static unsigned long zcache_flush_found;
+static unsigned long zcache_flobj_total;
+static unsigned long zcache_flobj_found;
+static unsigned long zcache_failed_eph_puts;
+static unsigned long zcache_nonactive_puts;
+static unsigned long zcache_failed_pers_puts;
+
+/*
+ * Tmem operations assume the poolid implies the invoking client.
+ * Zcache only has one client (the kernel itself): LOCAL_CLIENT.
+ * RAMster has each client numbered by cluster node, and a KVM version
+ * of zcache would have one client per guest and each client might
+ * have a poolid==N.
+ */
+static struct tmem_pool *zcache_get_pool_by_id(uint16_t cli_id, uint16_t poolid)
+{
+ struct tmem_pool *pool = NULL;
+ struct zcache_client *cli = NULL;
+
+ if (cli_id == LOCAL_CLIENT)
+ cli = &zcache_host;
+ else {
+ if (cli_id >= MAX_CLIENTS)
+ goto out;
+ cli = &zcache_clients[cli_id];
+ if (cli == NULL)
+ goto out;
+ atomic_inc(&cli->refcount);
+ }
+ if (poolid < MAX_POOLS_PER_CLIENT) {
+ pool = cli->tmem_pools[poolid];
+ if (pool != NULL)
+ atomic_inc(&pool->refcount);
+ }
+out:
+ return pool;
+}
+
+static void zcache_put_pool(struct tmem_pool *pool)
+{
+ struct zcache_client *cli = NULL;
+
+ if (pool == NULL)
+ BUG();
+ cli = pool->client;
+ atomic_dec(&pool->refcount);
+ atomic_dec(&cli->refcount);
+}
+
+int zcache_new_client(uint16_t cli_id)
+{
+ struct zcache_client *cli = NULL;
+ int ret = -1;
+
+ if (cli_id == LOCAL_CLIENT)
+ cli = &zcache_host;
+ else if ((unsigned int)cli_id < MAX_CLIENTS)
+ cli = &zcache_clients[cli_id];
+ if (cli == NULL)
+ goto out;
+ if (cli->allocated)
+ goto out;
+ cli->allocated = 1;
+#ifdef CONFIG_FRONTSWAP
+ cli->xvpool = xv_create_pool();
+ if (cli->xvpool == NULL)
+ goto out;
+#endif
+ ret = 0;
+out:
+ return ret;
+}
+
+/* counters for debugging */
+static unsigned long zcache_failed_get_free_pages;
+static unsigned long zcache_failed_alloc;
+static unsigned long zcache_put_to_flush;
+
+/*
+ * for now, used named slabs so can easily track usage; later can
+ * either just use kmalloc, or perhaps add a slab-like allocator
+ * to more carefully manage total memory utilization
+ */
+static struct kmem_cache *zcache_objnode_cache;
+static struct kmem_cache *zcache_obj_cache;
+static struct kmem_cache *ramster_flnode_cache;
+static atomic_t zcache_curr_obj_count = ATOMIC_INIT(0);
+static unsigned long zcache_curr_obj_count_max;
+static atomic_t zcache_curr_objnode_count = ATOMIC_INIT(0);
+static unsigned long zcache_curr_objnode_count_max;
+
+/*
+ * to avoid memory allocation recursion (e.g. due to direct reclaim), we
+ * preload all necessary data structures so the hostops callbacks never
+ * actually do a malloc
+ */
+struct zcache_preload {
+ void *page;
+ struct tmem_obj *obj;
+ int nr;
+ struct tmem_objnode *objnodes[OBJNODE_TREE_MAX_PATH];
+ struct flushlist_node *flnode;
+};
+static DEFINE_PER_CPU(struct zcache_preload, zcache_preloads) = { 0, };
+
+static int zcache_do_preload(struct tmem_pool *pool)
+{
+ struct zcache_preload *kp;
+ struct tmem_objnode *objnode;
+ struct tmem_obj *obj;
+ struct flushlist_node *flnode;
+ void *page;
+ int ret = -ENOMEM;
+
+ if (unlikely(zcache_objnode_cache == NULL))
+ goto out;
+ if (unlikely(zcache_obj_cache == NULL))
+ goto out;
+ preempt_disable();
+ kp = &__get_cpu_var(zcache_preloads);
+ while (kp->nr < ARRAY_SIZE(kp->objnodes)) {
+ preempt_enable_no_resched();
+ objnode = kmem_cache_alloc(zcache_objnode_cache,
+ ZCACHE_GFP_MASK);
+ if (unlikely(objnode == NULL)) {
+ zcache_failed_alloc++;
+ goto out;
+ }
+ preempt_disable();
+ kp = &__get_cpu_var(zcache_preloads);
+ if (kp->nr < ARRAY_SIZE(kp->objnodes))
+ kp->objnodes[kp->nr++] = objnode;
+ else
+ kmem_cache_free(zcache_objnode_cache, objnode);
+ }
+ preempt_enable_no_resched();
+ obj = kmem_cache_alloc(zcache_obj_cache, ZCACHE_GFP_MASK);
+ if (unlikely(obj == NULL)) {
+ zcache_failed_alloc++;
+ goto out;
+ }
+ flnode = kmem_cache_alloc(ramster_flnode_cache, ZCACHE_GFP_MASK);
+ if (unlikely(flnode == NULL)) {
+ zcache_failed_alloc++;
+ goto out;
+ }
+ if (is_ephemeral(pool)) {
+ page = (void *)__get_free_page(ZCACHE_GFP_MASK);
+ if (unlikely(page == NULL)) {
+ zcache_failed_get_free_pages++;
+ kmem_cache_free(zcache_obj_cache, obj);
+ kmem_cache_free(ramster_flnode_cache, flnode);
+ goto out;
+ }
+ }
+ preempt_disable();
+ kp = &__get_cpu_var(zcache_preloads);
+ if (kp->obj == NULL)
+ kp->obj = obj;
+ else
+ kmem_cache_free(zcache_obj_cache, obj);
+ if (kp->flnode == NULL)
+ kp->flnode = flnode;
+ else
+ kmem_cache_free(ramster_flnode_cache, flnode);
+ if (is_ephemeral(pool)) {
+ if (kp->page == NULL)
+ kp->page = page;
+ else
+ free_page((unsigned long)page);
+ }
+ ret = 0;
+out:
+ return ret;
+}
+
+static int ramster_do_preload_flnode_only(struct tmem_pool *pool)
+{
+ struct zcache_preload *kp;
+ struct flushlist_node *flnode;
+ int ret = -ENOMEM;
+
+ BUG_ON(!irqs_disabled());
+ if (unlikely(ramster_flnode_cache == NULL))
+ BUG();
+ kp = &__get_cpu_var(zcache_preloads);
+ flnode = kmem_cache_alloc(ramster_flnode_cache, GFP_ATOMIC);
+ if (unlikely(flnode == NULL) && kp->flnode == NULL)
+ BUG(); /* FIXME handle more gracefully, but how??? */
+ else if (kp->flnode == NULL)
+ kp->flnode = flnode;
+ else
+ kmem_cache_free(ramster_flnode_cache, flnode);
+ return ret;
+}
+
+static void *zcache_get_free_page(void)
+{
+ struct zcache_preload *kp;
+ void *page;
+
+ kp = &__get_cpu_var(zcache_preloads);
+ page = kp->page;
+ BUG_ON(page == NULL);
+ kp->page = NULL;
+ return page;
+}
+
+static void zcache_free_page(void *p)
+{
+ free_page((unsigned long)p);
+}
+
+/*
+ * zcache implementation for tmem host ops
+ */
+
+static struct tmem_objnode *zcache_objnode_alloc(struct tmem_pool *pool)
+{
+ struct tmem_objnode *objnode = NULL;
+ unsigned long count;
+ struct zcache_preload *kp;
+
+ kp = &__get_cpu_var(zcache_preloads);
+ if (kp->nr <= 0)
+ goto out;
+ objnode = kp->objnodes[kp->nr - 1];
+ BUG_ON(objnode == NULL);
+ kp->objnodes[kp->nr - 1] = NULL;
+ kp->nr--;
+ count = atomic_inc_return(&zcache_curr_objnode_count);
+ if (count > zcache_curr_objnode_count_max)
+ zcache_curr_objnode_count_max = count;
+out:
+ return objnode;
+}
+
+static void zcache_objnode_free(struct tmem_objnode *objnode,
+ struct tmem_pool *pool)
+{
+ atomic_dec(&zcache_curr_objnode_count);
+ BUG_ON(atomic_read(&zcache_curr_objnode_count) < 0);
+ kmem_cache_free(zcache_objnode_cache, objnode);
+}
+
+static struct tmem_obj *zcache_obj_alloc(struct tmem_pool *pool)
+{
+ struct tmem_obj *obj = NULL;
+ unsigned long count;
+ struct zcache_preload *kp;
+
+ kp = &__get_cpu_var(zcache_preloads);
+ obj = kp->obj;
+ BUG_ON(obj == NULL);
+ kp->obj = NULL;
+ count = atomic_inc_return(&zcache_curr_obj_count);
+ if (count > zcache_curr_obj_count_max)
+ zcache_curr_obj_count_max = count;
+ return obj;
+}
+
+static void zcache_obj_free(struct tmem_obj *obj, struct tmem_pool *pool)
+{
+ atomic_dec(&zcache_curr_obj_count);
+ BUG_ON(atomic_read(&zcache_curr_obj_count) < 0);
+ kmem_cache_free(zcache_obj_cache, obj);
+}
+
+static struct flushlist_node *ramster_flnode_alloc(struct tmem_pool *pool)
+{
+ struct flushlist_node *flnode = NULL;
+ struct zcache_preload *kp;
+ int count;
+
+ kp = &__get_cpu_var(zcache_preloads);
+ flnode = kp->flnode;
+ BUG_ON(flnode == NULL);
+ kp->flnode = NULL;
+ count = atomic_inc_return(&ramster_curr_flnode_count);
+ if (count > ramster_curr_flnode_count_max)
+ ramster_curr_flnode_count_max = count;
+ return flnode;
+}
+
+static void ramster_flnode_free(struct flushlist_node *flnode,
+ struct tmem_pool *pool)
+{
+ atomic_dec(&ramster_curr_flnode_count);
+ BUG_ON(atomic_read(&ramster_curr_flnode_count) < 0);
+ kmem_cache_free(ramster_flnode_cache, flnode);
+}
+
+static struct tmem_hostops zcache_hostops = {
+ .obj_alloc = zcache_obj_alloc,
+ .obj_free = zcache_obj_free,
+ .objnode_alloc = zcache_objnode_alloc,
+ .objnode_free = zcache_objnode_free,
+};
+
+/*
+ * zcache implementations for PAM page descriptor ops
+ */
+
+
+static inline void dec_and_check(atomic_t *pvar)
+{
+ atomic_dec(pvar);
+ /* later when all accounting is fixed, make this a BUG */
+ WARN_ON_ONCE(atomic_read(pvar) < 0);
+}
+
+static atomic_t zcache_curr_eph_pampd_count = ATOMIC_INIT(0);
+static unsigned long zcache_curr_eph_pampd_count_max;
+static atomic_t zcache_curr_pers_pampd_count = ATOMIC_INIT(0);
+static unsigned long zcache_curr_pers_pampd_count_max;
+
+/* forward reference */
+static int zcache_compress(struct page *from, void **out_va, size_t *out_len);
+
+static int zcache_pampd_eph_create(char *data, size_t size, bool raw,
+ struct tmem_pool *pool, struct tmem_oid *oid,
+ uint32_t index, void **pampd)
+{
+ int ret = -1;
+ void *cdata = data;
+ size_t clen = size;
+ struct zcache_client *cli = pool->client;
+ uint16_t client_id = get_client_id_from_client(cli);
+ struct page *page = NULL;
+ unsigned long count;
+
+ if (!raw) {
+ page = virt_to_page(data);
+ ret = zcache_compress(page, &cdata, &clen);
+ if (ret == 0)
+ goto out;
+ if (clen == 0 || clen > zbud_max_buddy_size()) {
+ zcache_compress_poor++;
+ goto out;
+ }
+ }
+ *pampd = (void *)zbud_create(client_id, pool->pool_id, oid,
+ index, page, cdata, clen);
+ if (*pampd == NULL) {
+ ret = -ENOMEM;
+ goto out;
+ }
+ ret = 0;
+ count = atomic_inc_return(&zcache_curr_eph_pampd_count);
+ if (count > zcache_curr_eph_pampd_count_max)
+ zcache_curr_eph_pampd_count_max = count;
+ if (client_id != LOCAL_CLIENT) {
+ count = atomic_inc_return(&ramster_foreign_eph_pampd_count);
+ if (count > ramster_foreign_eph_pampd_count_max)
+ ramster_foreign_eph_pampd_count_max = count;
+ }
+out:
+ return ret;
+}
+
+static int zcache_pampd_pers_create(char *data, size_t size, bool raw,
+ struct tmem_pool *pool, struct tmem_oid *oid,
+ uint32_t index, void **pampd)
+{
+ int ret = -1;
+ void *cdata = data;
+ size_t clen = size;
+ struct zcache_client *cli = pool->client;
+ struct page *page;
+ unsigned long count;
+ unsigned long zv_mean_zsize;
+ struct zv_hdr *zv;
+ long curr_pers_pampd_count;
+ u64 total_zsize;
+#ifdef RAMSTER_TESTING
+ static bool pampd_neg_warned;
+#endif
+
+ curr_pers_pampd_count = atomic_read(&zcache_curr_pers_pampd_count) -
+ atomic_read(&ramster_remote_pers_pages);
+#ifdef RAMSTER_TESTING
+ /* should always be positive, but warn if accounting is off */
+ if (!pampd_neg_warned) {
+ pr_warn("ramster: bad accounting for curr_pers_pampd_count\n");
+ pampd_neg_warned = true;
+ }
+#endif
+ if (curr_pers_pampd_count >
+ (zv_page_count_policy_percent * totalram_pages) / 100) {
+ zcache_policy_percent_exceeded++;
+ goto out;
+ }
+ if (raw)
+ goto ok_to_create;
+ page = virt_to_page(data);
+ if (zcache_compress(page, &cdata, &clen) == 0)
+ goto out;
+ /* reject if compression is too poor */
+ if (clen > zv_max_zsize) {
+ zcache_compress_poor++;
+ goto out;
+ }
+ /* reject if mean compression is too poor */
+ if ((clen > zv_max_mean_zsize) && (curr_pers_pampd_count > 0)) {
+ total_zsize = xv_get_total_size_bytes(cli->xvpool);
+ zv_mean_zsize = div_u64(total_zsize, curr_pers_pampd_count);
+ if (zv_mean_zsize > zv_max_mean_zsize) {
+ zcache_mean_compress_poor++;
+ goto out;
+ }
+ }
+ok_to_create:
+ *pampd = (void *)zv_create(cli, pool->pool_id, oid, index, cdata, clen);
+ if (*pampd == NULL) {
+ ret = -ENOMEM;
+ goto out;
+ }
+ ret = 0;
+ count = atomic_inc_return(&zcache_curr_pers_pampd_count);
+ if (count > zcache_curr_pers_pampd_count_max)
+ zcache_curr_pers_pampd_count_max = count;
+ if (is_local_client(cli))
+ goto out;
+ zv = *(struct zv_hdr **)pampd;
+ count = atomic_inc_return(&ramster_foreign_pers_pampd_count);
+ if (count > ramster_foreign_pers_pampd_count_max)
+ ramster_foreign_pers_pampd_count_max = count;
+out:
+ return ret;
+}
+
+static void *zcache_pampd_create(char *data, size_t size, bool raw, int eph,
+ struct tmem_pool *pool, struct tmem_oid *oid,
+ uint32_t index)
+{
+ void *pampd = NULL;
+ int ret;
+ bool ephemeral;
+
+ BUG_ON(preemptible());
+ ephemeral = (eph == 1) || ((eph == 0) && is_ephemeral(pool));
+ if (ephemeral)
+ ret = zcache_pampd_eph_create(data, size, raw, pool,
+ oid, index, &pampd);
+ else
+ ret = zcache_pampd_pers_create(data, size, raw, pool,
+ oid, index, &pampd);
+ /* FIXME add some counters here for failed creates? */
+ return pampd;
+}
+
+/*
+ * fill the pageframe corresponding to the struct page with the data
+ * from the passed pampd
+ */
+static int zcache_pampd_get_data(char *data, size_t *bufsize, bool raw,
+ void *pampd, struct tmem_pool *pool,
+ struct tmem_oid *oid, uint32_t index)
+{
+ int ret = 0;
+
+ BUG_ON(preemptible());
+ BUG_ON(is_ephemeral(pool)); /* Fix later for shared pools? */
+ BUG_ON(pampd_is_remote(pampd));
+ if (raw)
+ zv_copy_from_pampd(data, bufsize, pampd);
+ else
+ zv_decompress(virt_to_page(data), pampd);
+ return ret;
+}
+
+static int zcache_pampd_get_data_and_free(char *data, size_t *bufsize, bool raw,
+ void *pampd, struct tmem_pool *pool,
+ struct tmem_oid *oid, uint32_t index)
+{
+ int ret = 0;
+ unsigned long flags;
+ struct zcache_client *cli = pool->client;
+
+ BUG_ON(preemptible());
+ BUG_ON(pampd_is_remote(pampd));
+ if (is_ephemeral(pool)) {
+ local_irq_save(flags);
+ if (raw)
+ zbud_copy_from_pampd(data, bufsize, pampd);
+ else
+ ret = zbud_decompress(virt_to_page(data), pampd);
+ zbud_free_and_delist((struct zbud_hdr *)pampd);
+ local_irq_restore(flags);
+ if (!is_local_client(cli))
+ dec_and_check(&ramster_foreign_eph_pampd_count);
+ dec_and_check(&zcache_curr_eph_pampd_count);
+ } else {
+ if (is_local_client(cli))
+ BUG();
+ if (raw)
+ zv_copy_from_pampd(data, bufsize, pampd);
+ else
+ zv_decompress(virt_to_page(data), pampd);
+ zv_free(cli->xvpool, pampd);
+ if (!is_local_client(cli))
+ dec_and_check(&ramster_foreign_pers_pampd_count);
+ dec_and_check(&zcache_curr_pers_pampd_count);
+ ret = 0;
+ }
+ return ret;
+}
+
+static bool zcache_pampd_is_remote(void *pampd)
+{
+ return pampd_is_remote(pampd);
+}
+
+/*
+ * free the pampd and remove it from any zcache lists
+ * pampd must no longer be pointed to from any tmem data structures!
+ */
+static void zcache_pampd_free(void *pampd, struct tmem_pool *pool,
+ struct tmem_oid *oid, uint32_t index, bool acct)
+{
+ struct zcache_client *cli = pool->client;
+ bool eph = is_ephemeral(pool);
+ struct zv_hdr *zv;
+
+ BUG_ON(preemptible());
+ if (pampd_is_remote(pampd)) {
+ WARN_ON(acct == false);
+ if (oid == NULL) {
+ /*
+ * a NULL oid means to ignore this pampd free
+ * as the remote freeing will be handled elsewhere
+ */
+ } else if (eph) {
+ /* FIXME remote flush optional but probably good idea */
+ /* FIXME get these working properly again */
+ dec_and_check(&zcache_curr_eph_pampd_count);
+ } else if (pampd_is_intransit(pampd)) {
+ /* did a pers remote get_and_free, so just free local */
+ pampd = pampd_mask_intransit_and_remote(pampd);
+ goto local_pers;
+ } else {
+ struct flushlist_node *flnode =
+ ramster_flnode_alloc(pool);
+
+ flnode->xh.client_id = pampd_remote_node(pampd);
+ flnode->xh.pool_id = pool->pool_id;
+ flnode->xh.oid = *oid;
+ flnode->xh.index = index;
+ flnode->rem_op.op = RAMSTER_REMOTIFY_FLUSH_PAGE;
+ spin_lock(&zcache_rem_op_list_lock);
+ list_add(&flnode->rem_op.list, &zcache_rem_op_list);
+ spin_unlock(&zcache_rem_op_list_lock);
+ dec_and_check(&zcache_curr_pers_pampd_count);
+ dec_and_check(&ramster_remote_pers_pages);
+ }
+ } else if (eph) {
+ zbud_free_and_delist((struct zbud_hdr *)pampd);
+ if (!is_local_client(pool->client))
+ dec_and_check(&ramster_foreign_eph_pampd_count);
+ if (acct)
+ /* FIXME get these working properly again */
+ dec_and_check(&zcache_curr_eph_pampd_count);
+ } else {
+local_pers:
+ zv = (struct zv_hdr *)pampd;
+ if (!is_local_client(pool->client))
+ dec_and_check(&ramster_foreign_pers_pampd_count);
+ zv_free(cli->xvpool, zv);
+ if (acct)
+ /* FIXME get these working properly again */
+ dec_and_check(&zcache_curr_pers_pampd_count);
+ }
+}
+
+static void zcache_pampd_free_obj(struct tmem_pool *pool,
+ struct tmem_obj *obj)
+{
+ struct flushlist_node *flnode;
+
+ BUG_ON(preemptible());
+ if (obj->extra == NULL)
+ return;
+ BUG_ON(!pampd_is_remote(obj->extra));
+ flnode = ramster_flnode_alloc(pool);
+ flnode->xh.client_id = pampd_remote_node(obj->extra);
+ flnode->xh.pool_id = pool->pool_id;
+ flnode->xh.oid = obj->oid;
+ flnode->xh.index = FLUSH_ENTIRE_OBJECT;
+ flnode->rem_op.op = RAMSTER_REMOTIFY_FLUSH_OBJ;
+ spin_lock(&zcache_rem_op_list_lock);
+ list_add(&flnode->rem_op.list, &zcache_rem_op_list);
+ spin_unlock(&zcache_rem_op_list_lock);
+}
+
+void zcache_pampd_new_obj(struct tmem_obj *obj)
+{
+ obj->extra = NULL;
+}
+
+int zcache_pampd_replace_in_obj(void *new_pampd, struct tmem_obj *obj)
+{
+ int ret = -1;
+
+ if (new_pampd != NULL) {
+ if (obj->extra == NULL)
+ obj->extra = new_pampd;
+ /* enforce that all remote pages in an object reside
+ * in the same node! */
+ else if (pampd_remote_node(new_pampd) !=
+ pampd_remote_node((void *)(obj->extra)))
+ BUG();
+ ret = 0;
+ }
+ return ret;
+}
+
+/*
+ * Called by the message handler after a (still compressed) page has been
+ * fetched from the remote machine in response to an "is_remote" tmem_get
+ * or persistent tmem_localify. For a tmem_get, "extra" is the address of
+ * the page that is to be filled to succesfully resolve the tmem_get; for
+ * a (persistent) tmem_localify, "extra" is NULL (as the data is placed only
+ * in the local zcache). "data" points to "size" bytes of (compressed) data
+ * passed in the message. In the case of a persistent remote get, if
+ * pre-allocation was successful (see zcache_repatriate_preload), the page
+ * is placed into both local zcache and at "extra".
+ */
+int zcache_localify(int pool_id, struct tmem_oid *oidp,
+ uint32_t index, char *data, size_t size,
+ void *extra)
+{
+ int ret = -ENOENT;
+ unsigned long flags;
+ struct tmem_pool *pool;
+ bool ephemeral, delete = false;
+ size_t clen = PAGE_SIZE;
+ void *pampd, *saved_hb;
+ struct tmem_obj *obj;
+
+ pool = zcache_get_pool_by_id(LOCAL_CLIENT, pool_id);
+ if (unlikely(pool == NULL))
+ /* pool doesn't exist anymore */
+ goto out;
+ ephemeral = is_ephemeral(pool);
+ local_irq_save(flags); /* FIXME: maybe only disable softirqs? */
+ pampd = tmem_localify_get_pampd(pool, oidp, index, &obj, &saved_hb);
+ if (pampd == NULL) {
+ /* hmmm... must have been a flush while waiting */
+#ifdef RAMSTER_TESTING
+ pr_err("UNTESTED pampd==NULL in zcache_localify\n");
+#endif
+ if (ephemeral)
+ ramster_remote_eph_pages_unsucc_get++;
+ else
+ ramster_remote_pers_pages_unsucc_get++;
+ obj = NULL;
+ goto finish;
+ } else if (unlikely(!pampd_is_remote(pampd))) {
+ /* hmmm... must have been a dup put while waiting */
+#ifdef RAMSTER_TESTING
+ pr_err("UNTESTED dup while waiting in zcache_localify\n");
+#endif
+ if (ephemeral)
+ ramster_remote_eph_pages_unsucc_get++;
+ else
+ ramster_remote_pers_pages_unsucc_get++;
+ obj = NULL;
+ pampd = NULL;
+ ret = -EEXIST;
+ goto finish;
+ } else if (size == 0) {
+ /* no remote data, delete the local is_remote pampd */
+ pampd = NULL;
+ if (ephemeral)
+ ramster_remote_eph_pages_unsucc_get++;
+ else
+ BUG();
+ delete = true;
+ goto finish;
+ }
+ if (!ephemeral && pampd_is_intransit(pampd)) {
+ /* localify to zcache */
+ pampd = pampd_mask_intransit_and_remote(pampd);
+ zv_copy_to_pampd(pampd, data, size);
+ } else {
+ pampd = NULL;
+ obj = NULL;
+ }
+ if (extra != NULL) {
+ /* decompress direct-to-memory to complete remotify */
+ ret = lzo1x_decompress_safe((char *)data, size,
+ (char *)extra, &clen);
+ BUG_ON(ret != LZO_E_OK);
+ BUG_ON(clen != PAGE_SIZE);
+ }
+ if (ephemeral)
+ ramster_remote_eph_pages_succ_get++;
+ else
+ ramster_remote_pers_pages_succ_get++;
+ ret = 0;
+finish:
+ tmem_localify_finish(obj, index, pampd, saved_hb, delete);
+ zcache_put_pool(pool);
+ local_irq_restore(flags);
+out:
+ return ret;
+}
+
+/*
+ * Called on a remote persistent tmem_get to attempt to preallocate
+ * local storage for the data contained in the remote persistent page.
+ * If succesfully preallocated, returns the pampd, marked as remote and
+ * in_transit. Else returns NULL. Note that the appropriate tmem data
+ * structure must be locked.
+ */
+static void *zcache_pampd_repatriate_preload(void *pampd,
+ struct tmem_pool *pool,
+ struct tmem_oid *oid,
+ uint32_t index,
+ bool *intransit)
+{
+ int clen = pampd_remote_size(pampd);
+ void *ret_pampd = NULL;
+ unsigned long flags;
+
+ if (!pampd_is_remote(pampd))
+ BUG();
+ if (is_ephemeral(pool))
+ BUG();
+ if (pampd_is_intransit(pampd)) {
+ /*
+ * to avoid multiple allocations (and maybe a memory leak)
+ * don't preallocate if already in the process of being
+ * repatriated
+ */
+ *intransit = true;
+ goto out;
+ }
+ *intransit = false;
+ local_irq_save(flags);
+ ret_pampd = (void *)zv_alloc(pool, oid, index, clen);
+ if (ret_pampd != NULL) {
+ /*
+ * a pampd is marked intransit if it is remote and space has
+ * been allocated for it locally (note, only happens for
+ * persistent pages, in which case the remote copy is freed)
+ */
+ ret_pampd = pampd_mark_intransit(ret_pampd);
+ dec_and_check(&ramster_remote_pers_pages);
+ } else
+ ramster_pers_pages_remote_nomem++;
+ local_irq_restore(flags);
+out:
+ return ret_pampd;
+}
+
+/*
+ * Called on a remote tmem_get to invoke a message to fetch the page.
+ * Might sleep so no tmem locks can be held. "extra" is passed
+ * all the way through the round-trip messaging to zcache_localify.
+ */
+static int zcache_pampd_repatriate(void *fake_pampd, void *real_pampd,
+ struct tmem_pool *pool,
+ struct tmem_oid *oid, uint32_t index,
+ bool free, void *extra)
+{
+ struct tmem_xhandle xh;
+ int ret;
+
+ if (pampd_is_intransit(real_pampd))
+ /* have local space pre-reserved, so free remote copy */
+ free = true;
+ xh = tmem_xhandle_fill(LOCAL_CLIENT, pool, oid, index);
+ /* unreliable request/response for now */
+ ret = ramster_remote_async_get(&xh, free,
+ pampd_remote_node(fake_pampd),
+ pampd_remote_size(fake_pampd),
+ pampd_remote_cksum(fake_pampd),
+ extra);
+#ifdef RAMSTER_TESTING
+ if (ret != 0 && ret != -ENOENT)
+ pr_err("TESTING zcache_pampd_repatriate returns, ret=%d\n",
+ ret);
+#endif
+ return ret;
+}
+
+static struct tmem_pamops zcache_pamops = {
+ .create = zcache_pampd_create,
+ .get_data = zcache_pampd_get_data,
+ .free = zcache_pampd_free,
+ .get_data_and_free = zcache_pampd_get_data_and_free,
+ .free_obj = zcache_pampd_free_obj,
+ .is_remote = zcache_pampd_is_remote,
+ .repatriate_preload = zcache_pampd_repatriate_preload,
+ .repatriate = zcache_pampd_repatriate,
+ .new_obj = zcache_pampd_new_obj,
+ .replace_in_obj = zcache_pampd_replace_in_obj,
+};
+
+/*
+ * zcache compression/decompression and related per-cpu stuff
+ */
+
+#define LZO_WORKMEM_BYTES LZO1X_1_MEM_COMPRESS
+#define LZO_DSTMEM_PAGE_ORDER 1
+static DEFINE_PER_CPU(unsigned char *, zcache_workmem);
+static DEFINE_PER_CPU(unsigned char *, zcache_dstmem);
+
+static int zcache_compress(struct page *from, void **out_va, size_t *out_len)
+{
+ int ret = 0;
+ unsigned char *dmem = __get_cpu_var(zcache_dstmem);
+ unsigned char *wmem = __get_cpu_var(zcache_workmem);
+ char *from_va;
+
+ BUG_ON(!irqs_disabled());
+ if (unlikely(dmem == NULL || wmem == NULL))
+ goto out; /* no buffer, so can't compress */
- from_va = kmap_atomic(from, KM_USER0);
++ from_va = kmap_atomic(from);
+ mb();
+ ret = lzo1x_1_compress(from_va, PAGE_SIZE, dmem, out_len, wmem);
+ BUG_ON(ret != LZO_E_OK);
+ *out_va = dmem;
- kunmap_atomic(from_va, KM_USER0);
++ kunmap_atomic(from_va);
+ ret = 1;
+out:
+ return ret;
+}
+
+
+static int zcache_cpu_notifier(struct notifier_block *nb,
+ unsigned long action, void *pcpu)
+{
+ int cpu = (long)pcpu;
+ struct zcache_preload *kp;
+
+ switch (action) {
+ case CPU_UP_PREPARE:
+ per_cpu(zcache_dstmem, cpu) = (void *)__get_free_pages(
+ GFP_KERNEL | __GFP_REPEAT,
+ LZO_DSTMEM_PAGE_ORDER),
+ per_cpu(zcache_workmem, cpu) =
+ kzalloc(LZO1X_MEM_COMPRESS,
+ GFP_KERNEL | __GFP_REPEAT);
+ per_cpu(zcache_remoteputmem, cpu) =
+ kzalloc(PAGE_SIZE, GFP_KERNEL | __GFP_REPEAT);
+ break;
+ case CPU_DEAD:
+ case CPU_UP_CANCELED:
+ kfree(per_cpu(zcache_remoteputmem, cpu));
+ per_cpu(zcache_remoteputmem, cpu) = NULL;
+ free_pages((unsigned long)per_cpu(zcache_dstmem, cpu),
+ LZO_DSTMEM_PAGE_ORDER);
+ per_cpu(zcache_dstmem, cpu) = NULL;
+ kfree(per_cpu(zcache_workmem, cpu));
+ per_cpu(zcache_workmem, cpu) = NULL;
+ kp = &per_cpu(zcache_preloads, cpu);
+ while (kp->nr) {
+ kmem_cache_free(zcache_objnode_cache,
+ kp->objnodes[kp->nr - 1]);
+ kp->objnodes[kp->nr - 1] = NULL;
+ kp->nr--;
+ }
+ if (kp->obj) {
+ kmem_cache_free(zcache_obj_cache, kp->obj);
+ kp->obj = NULL;
+ }
+ if (kp->flnode) {
+ kmem_cache_free(ramster_flnode_cache, kp->flnode);
+ kp->flnode = NULL;
+ }
+ if (kp->page) {
+ free_page((unsigned long)kp->page);
+ kp->page = NULL;
+ }
+ break;
+ default:
+ break;
+ }
+ return NOTIFY_OK;
+}
+
+static struct notifier_block zcache_cpu_notifier_block = {
+ .notifier_call = zcache_cpu_notifier
+};
+
+#ifdef CONFIG_SYSFS
+#define ZCACHE_SYSFS_RO(_name) \
+ static ssize_t zcache_##_name##_show(struct kobject *kobj, \
+ struct kobj_attribute *attr, char *buf) \
+ { \
+ return sprintf(buf, "%lu\n", zcache_##_name); \
+ } \
+ static struct kobj_attribute zcache_##_name##_attr = { \
+ .attr = { .name = __stringify(_name), .mode = 0444 }, \
+ .show = zcache_##_name##_show, \
+ }
+
+#define ZCACHE_SYSFS_RO_ATOMIC(_name) \
+ static ssize_t zcache_##_name##_show(struct kobject *kobj, \
+ struct kobj_attribute *attr, char *buf) \
+ { \
+ return sprintf(buf, "%d\n", atomic_read(&zcache_##_name)); \
+ } \
+ static struct kobj_attribute zcache_##_name##_attr = { \
+ .attr = { .name = __stringify(_name), .mode = 0444 }, \
+ .show = zcache_##_name##_show, \
+ }
+
+#define ZCACHE_SYSFS_RO_CUSTOM(_name, _func) \
+ static ssize_t zcache_##_name##_show(struct kobject *kobj, \
+ struct kobj_attribute *attr, char *buf) \
+ { \
+ return _func(buf); \
+ } \
+ static struct kobj_attribute zcache_##_name##_attr = { \
+ .attr = { .name = __stringify(_name), .mode = 0444 }, \
+ .show = zcache_##_name##_show, \
+ }
+
+ZCACHE_SYSFS_RO(curr_obj_count_max);
+ZCACHE_SYSFS_RO(curr_objnode_count_max);
+ZCACHE_SYSFS_RO(flush_total);
+ZCACHE_SYSFS_RO(flush_found);
+ZCACHE_SYSFS_RO(flobj_total);
+ZCACHE_SYSFS_RO(flobj_found);
+ZCACHE_SYSFS_RO(failed_eph_puts);
+ZCACHE_SYSFS_RO(nonactive_puts);
+ZCACHE_SYSFS_RO(failed_pers_puts);
+ZCACHE_SYSFS_RO(zbud_curr_zbytes);
+ZCACHE_SYSFS_RO(zbud_cumul_zpages);
+ZCACHE_SYSFS_RO(zbud_cumul_zbytes);
+ZCACHE_SYSFS_RO(zbud_buddied_count);
+ZCACHE_SYSFS_RO(evicted_raw_pages);
+ZCACHE_SYSFS_RO(evicted_unbuddied_pages);
+ZCACHE_SYSFS_RO(evicted_buddied_pages);
+ZCACHE_SYSFS_RO(failed_get_free_pages);
+ZCACHE_SYSFS_RO(failed_alloc);
+ZCACHE_SYSFS_RO(put_to_flush);
+ZCACHE_SYSFS_RO(compress_poor);
+ZCACHE_SYSFS_RO(mean_compress_poor);
+ZCACHE_SYSFS_RO(policy_percent_exceeded);
+ZCACHE_SYSFS_RO_ATOMIC(zbud_curr_raw_pages);
+ZCACHE_SYSFS_RO_ATOMIC(zbud_curr_zpages);
+ZCACHE_SYSFS_RO_ATOMIC(curr_obj_count);
+ZCACHE_SYSFS_RO_ATOMIC(curr_objnode_count);
+ZCACHE_SYSFS_RO_CUSTOM(zbud_unbuddied_list_counts,
+ zbud_show_unbuddied_list_counts);
+ZCACHE_SYSFS_RO_CUSTOM(zbud_cumul_chunk_counts,
+ zbud_show_cumul_chunk_counts);
+ZCACHE_SYSFS_RO_CUSTOM(zv_curr_dist_counts,
+ zv_curr_dist_counts_show);
+ZCACHE_SYSFS_RO_CUSTOM(zv_cumul_dist_counts,
+ zv_cumul_dist_counts_show);
+
+static struct attribute *zcache_attrs[] = {
+ &zcache_curr_obj_count_attr.attr,
+ &zcache_curr_obj_count_max_attr.attr,
+ &zcache_curr_objnode_count_attr.attr,
+ &zcache_curr_objnode_count_max_attr.attr,
+ &zcache_flush_total_attr.attr,
+ &zcache_flobj_total_attr.attr,
+ &zcache_flush_found_attr.attr,
+ &zcache_flobj_found_attr.attr,
+ &zcache_failed_eph_puts_attr.attr,
+ &zcache_nonactive_puts_attr.attr,
+ &zcache_failed_pers_puts_attr.attr,
+ &zcache_policy_percent_exceeded_attr.attr,
+ &zcache_compress_poor_attr.attr,
+ &zcache_mean_compress_poor_attr.attr,
+ &zcache_zbud_curr_raw_pages_attr.attr,
+ &zcache_zbud_curr_zpages_attr.attr,
+ &zcache_zbud_curr_zbytes_attr.attr,
+ &zcache_zbud_cumul_zpages_attr.attr,
+ &zcache_zbud_cumul_zbytes_attr.attr,
+ &zcache_zbud_buddied_count_attr.attr,
+ &zcache_evicted_raw_pages_attr.attr,
+ &zcache_evicted_unbuddied_pages_attr.attr,
+ &zcache_evicted_buddied_pages_attr.attr,
+ &zcache_failed_get_free_pages_attr.attr,
+ &zcache_failed_alloc_attr.attr,
+ &zcache_put_to_flush_attr.attr,
+ &zcache_zbud_unbuddied_list_counts_attr.attr,
+ &zcache_zbud_cumul_chunk_counts_attr.attr,
+ &zcache_zv_curr_dist_counts_attr.attr,
+ &zcache_zv_cumul_dist_counts_attr.attr,
+ &zcache_zv_max_zsize_attr.attr,
+ &zcache_zv_max_mean_zsize_attr.attr,
+ &zcache_zv_page_count_policy_percent_attr.attr,
+ NULL,
+};
+
+static struct attribute_group zcache_attr_group = {
+ .attrs = zcache_attrs,
+ .name = "zcache",
+};
+
+#define RAMSTER_SYSFS_RO(_name) \
+ static ssize_t ramster_##_name##_show(struct kobject *kobj, \
+ struct kobj_attribute *attr, char *buf) \
+ { \
+ return sprintf(buf, "%lu\n", ramster_##_name); \
+ } \
+ static struct kobj_attribute ramster_##_name##_attr = { \
+ .attr = { .name = __stringify(_name), .mode = 0444 }, \
+ .show = ramster_##_name##_show, \
+ }
+
+#define RAMSTER_SYSFS_RW(_name) \
+ static ssize_t ramster_##_name##_show(struct kobject *kobj, \
+ struct kobj_attribute *attr, char *buf) \
+ { \
+ return sprintf(buf, "%lu\n", ramster_##_name); \
+ } \
+ static ssize_t ramster_##_name##_store(struct kobject *kobj, \
+ struct kobj_attribute *attr, const char *buf, size_t count) \
+ { \
+ int err; \
+ unsigned long enable; \
+ err = kstrtoul(buf, 10, &enable); \
+ if (err) \
+ return -EINVAL; \
+ ramster_##_name = enable; \
+ return count; \
+ } \
+ static struct kobj_attribute ramster_##_name##_attr = { \
+ .attr = { .name = __stringify(_name), .mode = 0644 }, \
+ .show = ramster_##_name##_show, \
+ .store = ramster_##_name##_store, \
+ }
+
+#define RAMSTER_SYSFS_RO_ATOMIC(_name) \
+ static ssize_t ramster_##_name##_show(struct kobject *kobj, \
+ struct kobj_attribute *attr, char *buf) \
+ { \
+ return sprintf(buf, "%d\n", atomic_read(&ramster_##_name)); \
+ } \
+ static struct kobj_attribute ramster_##_name##_attr = { \
+ .attr = { .name = __stringify(_name), .mode = 0444 }, \
+ .show = ramster_##_name##_show, \
+ }
+
+RAMSTER_SYSFS_RO(interface_revision);
+RAMSTER_SYSFS_RO_ATOMIC(remote_pers_pages);
+RAMSTER_SYSFS_RW(pers_remotify_enable);
+RAMSTER_SYSFS_RW(eph_remotify_enable);
+RAMSTER_SYSFS_RO(eph_pages_remoted);
+RAMSTER_SYSFS_RO(eph_pages_remote_failed);
+RAMSTER_SYSFS_RO(pers_pages_remoted);
+RAMSTER_SYSFS_RO(pers_pages_remote_failed);
+RAMSTER_SYSFS_RO(pers_pages_remote_nomem);
+RAMSTER_SYSFS_RO(remote_pages_flushed);
+RAMSTER_SYSFS_RO(remote_page_flushes_failed);
+RAMSTER_SYSFS_RO(remote_objects_flushed);
+RAMSTER_SYSFS_RO(remote_object_flushes_failed);
+RAMSTER_SYSFS_RO(remote_eph_pages_succ_get);
+RAMSTER_SYSFS_RO(remote_eph_pages_unsucc_get);
+RAMSTER_SYSFS_RO(remote_pers_pages_succ_get);
+RAMSTER_SYSFS_RO(remote_pers_pages_unsucc_get);
+RAMSTER_SYSFS_RO_ATOMIC(foreign_eph_pampd_count);
+RAMSTER_SYSFS_RO(foreign_eph_pampd_count_max);
+RAMSTER_SYSFS_RO_ATOMIC(foreign_pers_pampd_count);
+RAMSTER_SYSFS_RO(foreign_pers_pampd_count_max);
+RAMSTER_SYSFS_RO_ATOMIC(curr_flnode_count);
+RAMSTER_SYSFS_RO(curr_flnode_count_max);
+
+#define MANUAL_NODES 8
+static bool ramster_nodes_manual_up[MANUAL_NODES];
+static ssize_t ramster_manual_node_up_show(struct kobject *kobj,
+ struct kobj_attribute *attr, char *buf)
+{
+ int i;
+ char *p = buf;
+ for (i = 0; i < MANUAL_NODES; i++)
+ if (ramster_nodes_manual_up[i])
+ p += sprintf(p, "%d ", i);
+ p += sprintf(p, "\n");
+ return p - buf;
+}
+
+static ssize_t ramster_manual_node_up_store(struct kobject *kobj,
+ struct kobj_attribute *attr, const char *buf, size_t count)
+{
+ int err;
+ unsigned long node_num;
+
+ err = kstrtoul(buf, 10, &node_num);
+ if (err) {
+ pr_err("ramster: bad strtoul?\n");
+ return -EINVAL;
+ }
+ if (node_num >= MANUAL_NODES) {
+ pr_err("ramster: bad node_num=%lu?\n", node_num);
+ return -EINVAL;
+ }
+ if (ramster_nodes_manual_up[node_num]) {
+ pr_err("ramster: node %d already up, ignoring\n",
+ (int)node_num);
+ } else {
+ ramster_nodes_manual_up[node_num] = true;
+ r2net_hb_node_up_manual((int)node_num);
+ }
+ return count;
+}
+
+static struct kobj_attribute ramster_manual_node_up_attr = {
+ .attr = { .name = "manual_node_up", .mode = 0644 },
+ .show = ramster_manual_node_up_show,
+ .store = ramster_manual_node_up_store,
+};
+
+static ssize_t ramster_remote_target_nodenum_show(struct kobject *kobj,
+ struct kobj_attribute *attr, char *buf)
+{
+ if (ramster_remote_target_nodenum == -1UL)
+ return sprintf(buf, "unset\n");
+ else
+ return sprintf(buf, "%d\n", ramster_remote_target_nodenum);
+}
+
+static ssize_t ramster_remote_target_nodenum_store(struct kobject *kobj,
+ struct kobj_attribute *attr, const char *buf, size_t count)
+{
+ int err;
+ unsigned long node_num;
+
+ err = kstrtoul(buf, 10, &node_num);
+ if (err) {
+ pr_err("ramster: bad strtoul?\n");
+ return -EINVAL;
+ } else if (node_num == -1UL) {
+ pr_err("ramster: disabling all remotification, "
+ "data may still reside on remote nodes however\n");
+ return -EINVAL;
+ } else if (node_num >= MANUAL_NODES) {
+ pr_err("ramster: bad node_num=%lu?\n", node_num);
+ return -EINVAL;
+ } else if (!ramster_nodes_manual_up[node_num]) {
+ pr_err("ramster: node %d not up, ignoring setting "
+ "of remotification target\n", (int)node_num);
+ } else if (r2net_remote_target_node_set((int)node_num) >= 0) {
+ pr_info("ramster: node %d set as remotification target\n",
+ (int)node_num);
+ ramster_remote_target_nodenum = (int)node_num;
+ } else {
+ pr_err("ramster: bad num to node node_num=%d?\n",
+ (int)node_num);
+ return -EINVAL;
+ }
+ return count;
+}
+
+static struct kobj_attribute ramster_remote_target_nodenum_attr = {
+ .attr = { .name = "remote_target_nodenum", .mode = 0644 },
+ .show = ramster_remote_target_nodenum_show,
+ .store = ramster_remote_target_nodenum_store,
+};
+
+
+static struct attribute *ramster_attrs[] = {
+ &ramster_interface_revision_attr.attr,
+ &ramster_pers_remotify_enable_attr.attr,
+ &ramster_eph_remotify_enable_attr.attr,
+ &ramster_remote_pers_pages_attr.attr,
+ &ramster_eph_pages_remoted_attr.attr,
+ &ramster_eph_pages_remote_failed_attr.attr,
+ &ramster_pers_pages_remoted_attr.attr,
+ &ramster_pers_pages_remote_failed_attr.attr,
+ &ramster_pers_pages_remote_nomem_attr.attr,
+ &ramster_remote_pages_flushed_attr.attr,
+ &ramster_remote_page_flushes_failed_attr.attr,
+ &ramster_remote_objects_flushed_attr.attr,
+ &ramster_remote_object_flushes_failed_attr.attr,
+ &ramster_remote_eph_pages_succ_get_attr.attr,
+ &ramster_remote_eph_pages_unsucc_get_attr.attr,
+ &ramster_remote_pers_pages_succ_get_attr.attr,
+ &ramster_remote_pers_pages_unsucc_get_attr.attr,
+ &ramster_foreign_eph_pampd_count_attr.attr,
+ &ramster_foreign_eph_pampd_count_max_attr.attr,
+ &ramster_foreign_pers_pampd_count_attr.attr,
+ &ramster_foreign_pers_pampd_count_max_attr.attr,
+ &ramster_curr_flnode_count_attr.attr,
+ &ramster_curr_flnode_count_max_attr.attr,
+ &ramster_manual_node_up_attr.attr,
+ &ramster_remote_target_nodenum_attr.attr,
+ NULL,
+};
+
+static struct attribute_group ramster_attr_group = {
+ .attrs = ramster_attrs,
+ .name = "ramster",
+};
+
+#endif /* CONFIG_SYSFS */
+/*
+ * When zcache is disabled ("frozen"), pools can be created and destroyed,
+ * but all puts (and thus all other operations that require memory allocation)
+ * must fail. If zcache is unfrozen, accepts puts, then frozen again,
+ * data consistency requires all puts while frozen to be converted into
+ * flushes.
+ */
+static bool zcache_freeze;
+
+/*
+ * zcache shrinker interface (only useful for ephemeral pages, so zbud only)
+ */
+static int shrink_zcache_memory(struct shrinker *shrink,
+ struct shrink_control *sc)
+{
+ int ret = -1;
+ int nr = sc->nr_to_scan;
+ gfp_t gfp_mask = sc->gfp_mask;
+
+ if (nr >= 0) {
+ if (!(gfp_mask & __GFP_FS))
+ /* does this case really need to be skipped? */
+ goto out;
+ zbud_evict_pages(nr);
+ }
+ ret = (int)atomic_read(&zcache_zbud_curr_raw_pages);
+out:
+ return ret;
+}
+
+static struct shrinker zcache_shrinker = {
+ .shrink = shrink_zcache_memory,
+ .seeks = DEFAULT_SEEKS,
+};
+
+/*
+ * zcache shims between cleancache/frontswap ops and tmem
+ */
+
+int zcache_put(int cli_id, int pool_id, struct tmem_oid *oidp,
+ uint32_t index, char *data, size_t size,
+ bool raw, int ephemeral)
+{
+ struct tmem_pool *pool;
+ int ret = -1;
+
+ BUG_ON(!irqs_disabled());
+ pool = zcache_get_pool_by_id(cli_id, pool_id);
+ if (unlikely(pool == NULL))
+ goto out;
+ if (!zcache_freeze && zcache_do_preload(pool) == 0) {
+ /* preload does preempt_disable on success */
+ ret = tmem_put(pool, oidp, index, data, size, raw, ephemeral);
+ if (ret < 0) {
+ if (is_ephemeral(pool))
+ zcache_failed_eph_puts++;
+ else
+ zcache_failed_pers_puts++;
+ }
+ zcache_put_pool(pool);
+ preempt_enable_no_resched();
+ } else {
+ zcache_put_to_flush++;
+ if (atomic_read(&pool->obj_count) > 0)
+ /* the put fails whether the flush succeeds or not */
+ (void)tmem_flush_page(pool, oidp, index);
+ zcache_put_pool(pool);
+ }
+out:
+ return ret;
+}
+
+int zcache_get(int cli_id, int pool_id, struct tmem_oid *oidp,
+ uint32_t index, char *data, size_t *sizep,
+ bool raw, int get_and_free)
+{
+ struct tmem_pool *pool;
+ int ret = -1;
+ bool eph;
+
+ if (!raw) {
+ BUG_ON(irqs_disabled());
+ BUG_ON(in_softirq());
+ }
+ pool = zcache_get_pool_by_id(cli_id, pool_id);
+ eph = is_ephemeral(pool);
+ if (likely(pool != NULL)) {
+ if (atomic_read(&pool->obj_count) > 0)
+ ret = tmem_get(pool, oidp, index, data, sizep,
+ raw, get_and_free);
+ zcache_put_pool(pool);
+ }
+ WARN_ONCE((!eph && (ret != 0)), "zcache_get fails on persistent pool, "
+ "bad things are very likely to happen soon\n");
+#ifdef RAMSTER_TESTING
+ if (ret != 0 && ret != -1 && !(ret == -EINVAL && is_ephemeral(pool)))
+ pr_err("TESTING zcache_get tmem_get returns ret=%d\n", ret);
+#endif
+ if (ret == -EAGAIN)
+ BUG(); /* FIXME... don't need this anymore??? let's ensure */
+ return ret;
+}
+
+int zcache_flush(int cli_id, int pool_id,
+ struct tmem_oid *oidp, uint32_t index)
+{
+ struct tmem_pool *pool;
+ int ret = -1;
+ unsigned long flags;
+
+ local_irq_save(flags);
+ zcache_flush_total++;
+ pool = zcache_get_pool_by_id(cli_id, pool_id);
+ ramster_do_preload_flnode_only(pool);
+ if (likely(pool != NULL)) {
+ if (atomic_read(&pool->obj_count) > 0)
+ ret = tmem_flush_page(pool, oidp, index);
+ zcache_put_pool(pool);
+ }
+ if (ret >= 0)
+ zcache_flush_found++;
+ local_irq_restore(flags);
+ return ret;
+}
+
+int zcache_flush_object(int cli_id, int pool_id, struct tmem_oid *oidp)
+{
+ struct tmem_pool *pool;
+ int ret = -1;
+ unsigned long flags;
+
+ local_irq_save(flags);
+ zcache_flobj_total++;
+ pool = zcache_get_pool_by_id(cli_id, pool_id);
+ ramster_do_preload_flnode_only(pool);
+ if (likely(pool != NULL)) {
+ if (atomic_read(&pool->obj_count) > 0)
+ ret = tmem_flush_object(pool, oidp);
+ zcache_put_pool(pool);
+ }
+ if (ret >= 0)
+ zcache_flobj_found++;
+ local_irq_restore(flags);
+ return ret;
+}
+
+int zcache_client_destroy_pool(int cli_id, int pool_id)
+{
+ struct tmem_pool *pool = NULL;
+ struct zcache_client *cli = NULL;
+ int ret = -1;
+
+ if (pool_id < 0)
+ goto out;
+ if (cli_id == LOCAL_CLIENT)
+ cli = &zcache_host;
+ else if ((unsigned int)cli_id < MAX_CLIENTS)
+ cli = &zcache_clients[cli_id];
+ if (cli == NULL)
+ goto out;
+ atomic_inc(&cli->refcount);
+ pool = cli->tmem_pools[pool_id];
+ if (pool == NULL)
+ goto out;
+ cli->tmem_pools[pool_id] = NULL;
+ /* wait for pool activity on other cpus to quiesce */
+ while (atomic_read(&pool->refcount) != 0)
+ ;
+ atomic_dec(&cli->refcount);
+ local_bh_disable();
+ ret = tmem_destroy_pool(pool);
+ local_bh_enable();
+ kfree(pool);
+ pr_info("ramster: destroyed pool id=%d cli_id=%d\n", pool_id, cli_id);
+out:
+ return ret;
+}
+
+static int zcache_destroy_pool(int pool_id)
+{
+ return zcache_client_destroy_pool(LOCAL_CLIENT, pool_id);
+}
+
+int zcache_new_pool(uint16_t cli_id, uint32_t flags)
+{
+ int poolid = -1;
+ struct tmem_pool *pool;
+ struct zcache_client *cli = NULL;
+
+ if (cli_id == LOCAL_CLIENT)
+ cli = &zcache_host;
+ else if ((unsigned int)cli_id < MAX_CLIENTS)
+ cli = &zcache_clients[cli_id];
+ if (cli == NULL)
+ goto out;
+ atomic_inc(&cli->refcount);
+ pool = kmalloc(sizeof(struct tmem_pool), GFP_ATOMIC);
+ if (pool == NULL) {
+ pr_info("ramster: pool creation failed: out of memory\n");
+ goto out;
+ }
+
+ for (poolid = 0; poolid < MAX_POOLS_PER_CLIENT; poolid++)
+ if (cli->tmem_pools[poolid] == NULL)
+ break;
+ if (poolid >= MAX_POOLS_PER_CLIENT) {
+ pr_info("ramster: pool creation failed: max exceeded\n");
+ kfree(pool);
+ poolid = -1;
+ goto out;
+ }
+ atomic_set(&pool->refcount, 0);
+ pool->client = cli;
+ pool->pool_id = poolid;
+ tmem_new_pool(pool, flags);
+ cli->tmem_pools[poolid] = pool;
+ if (cli_id == LOCAL_CLIENT)
+ pr_info("ramster: created %s tmem pool, id=%d, local client\n",
+ flags & TMEM_POOL_PERSIST ? "persistent" : "ephemeral",
+ poolid);
+ else
+ pr_info("ramster: created %s tmem pool, id=%d, client=%d\n",
+ flags & TMEM_POOL_PERSIST ? "persistent" : "ephemeral",
+ poolid, cli_id);
+out:
+ if (cli != NULL)
+ atomic_dec(&cli->refcount);
+ return poolid;
+}
+
+static int zcache_local_new_pool(uint32_t flags)
+{
+ return zcache_new_pool(LOCAL_CLIENT, flags);
+}
+
+int zcache_autocreate_pool(int cli_id, int pool_id, bool ephemeral)
+{
+ struct tmem_pool *pool;
+ struct zcache_client *cli = NULL;
+ uint32_t flags = ephemeral ? 0 : TMEM_POOL_PERSIST;
+ int ret = -1;
+
+ if (cli_id == LOCAL_CLIENT)
+ goto out;
+ if (pool_id >= MAX_POOLS_PER_CLIENT)
+ goto out;
+ else if ((unsigned int)cli_id < MAX_CLIENTS)
+ cli = &zcache_clients[cli_id];
+ if ((ephemeral && !use_cleancache) || (!ephemeral && !use_frontswap))
+ BUG(); /* FIXME, handle more gracefully later */
+ if (!cli->allocated) {
+ if (zcache_new_client(cli_id))
+ BUG(); /* FIXME, handle more gracefully later */
+ cli = &zcache_clients[cli_id];
+ }
+ atomic_inc(&cli->refcount);
+ pool = cli->tmem_pools[pool_id];
+ if (pool != NULL) {
+ if (pool->persistent && ephemeral) {
+ pr_err("zcache_autocreate_pool: type mismatch\n");
+ goto out;
+ }
+ ret = 0;
+ goto out;
+ }
+ pool = kmalloc(sizeof(struct tmem_pool), GFP_KERNEL);
+ if (pool == NULL) {
+ pr_info("ramster: pool creation failed: out of memory\n");
+ goto out;
+ }
+ atomic_set(&pool->refcount, 0);
+ pool->client = cli;
+ pool->pool_id = pool_id;
+ tmem_new_pool(pool, flags);
+ cli->tmem_pools[pool_id] = pool;
+ pr_info("ramster: AUTOcreated %s tmem poolid=%d, for remote client=%d\n",
+ flags & TMEM_POOL_PERSIST ? "persistent" : "ephemeral",
+ pool_id, cli_id);
+ ret = 0;
+out:
+ if (cli == NULL)
+ BUG(); /* FIXME, handle more gracefully later */
+ /* pr_err("zcache_autocreate_pool: failed\n"); */
+ if (cli != NULL)
+ atomic_dec(&cli->refcount);
+ return ret;
+}
+
+/**********
+ * Two kernel functionalities currently can be layered on top of tmem.
+ * These are "cleancache" which is used as a second-chance cache for clean
+ * page cache pages; and "frontswap" which is used for swap pages
+ * to avoid writes to disk. A generic "shim" is provided here for each
+ * to translate in-kernel semantics to zcache semantics.
+ */
+
+#ifdef CONFIG_CLEANCACHE
+static void zcache_cleancache_put_page(int pool_id,
+ struct cleancache_filekey key,
+ pgoff_t index, struct page *page)
+{
+ u32 ind = (u32) index;
+ struct tmem_oid oid = *(struct tmem_oid *)&key;
+
+#ifdef __PG_WAS_ACTIVE
+ if (!PageWasActive(page)) {
+ zcache_nonactive_puts++;
+ return;
+ }
+#endif
+ if (likely(ind == index)) {
+ char *kva = page_address(page);
+
+ (void)zcache_put(LOCAL_CLIENT, pool_id, &oid, index,
+ kva, PAGE_SIZE, 0, 1);
+ }
+}
+
+static int zcache_cleancache_get_page(int pool_id,
+ struct cleancache_filekey key,
+ pgoff_t index, struct page *page)
+{
+ u32 ind = (u32) index;
+ struct tmem_oid oid = *(struct tmem_oid *)&key;
+ int ret = -1;
+
+ preempt_disable();
+ if (likely(ind == index)) {
+ char *kva = page_address(page);
+ size_t size = PAGE_SIZE;
+
+ ret = zcache_get(LOCAL_CLIENT, pool_id, &oid, index,
+ kva, &size, 0, 0);
+#ifdef __PG_WAS_ACTIVE
+ if (ret == 0)
+ SetPageWasActive(page);
+#endif
+ }
+ preempt_enable();
+ return ret;
+}
+
+static void zcache_cleancache_flush_page(int pool_id,
+ struct cleancache_filekey key,
+ pgoff_t index)
+{
+ u32 ind = (u32) index;
+ struct tmem_oid oid = *(struct tmem_oid *)&key;
+
+ if (likely(ind == index))
+ (void)zcache_flush(LOCAL_CLIENT, pool_id, &oid, ind);
+}
+
+static void zcache_cleancache_flush_inode(int pool_id,
+ struct cleancache_filekey key)
+{
+ struct tmem_oid oid = *(struct tmem_oid *)&key;
+
+ (void)zcache_flush_object(LOCAL_CLIENT, pool_id, &oid);
+}
+
+static void zcache_cleancache_flush_fs(int pool_id)
+{
+ if (pool_id >= 0)
+ (void)zcache_destroy_pool(pool_id);
+}
+
+static int zcache_cleancache_init_fs(size_t pagesize)
+{
+ BUG_ON(sizeof(struct cleancache_filekey) !=
+ sizeof(struct tmem_oid));
+ BUG_ON(pagesize != PAGE_SIZE);
+ return zcache_local_new_pool(0);
+}
+
+static int zcache_cleancache_init_shared_fs(char *uuid, size_t pagesize)
+{
+ /* shared pools are unsupported and map to private */
+ BUG_ON(sizeof(struct cleancache_filekey) !=
+ sizeof(struct tmem_oid));
+ BUG_ON(pagesize != PAGE_SIZE);
+ return zcache_local_new_pool(0);
+}
+
+static struct cleancache_ops zcache_cleancache_ops = {
+ .put_page = zcache_cleancache_put_page,
+ .get_page = zcache_cleancache_get_page,
+ .invalidate_page = zcache_cleancache_flush_page,
+ .invalidate_inode = zcache_cleancache_flush_inode,
+ .invalidate_fs = zcache_cleancache_flush_fs,
+ .init_shared_fs = zcache_cleancache_init_shared_fs,
+ .init_fs = zcache_cleancache_init_fs
+};
+
+struct cleancache_ops zcache_cleancache_register_ops(void)
+{
+ struct cleancache_ops old_ops =
+ cleancache_register_ops(&zcache_cleancache_ops);
+
+ return old_ops;
+}
+#endif
+
+#ifdef CONFIG_FRONTSWAP
+/* a single tmem poolid is used for all frontswap "types" (swapfiles) */
+static int zcache_frontswap_poolid = -1;
+
+/*
+ * Swizzling increases objects per swaptype, increasing tmem concurrency
+ * for heavy swaploads. Later, larger nr_cpus -> larger SWIZ_BITS
+ */
+#define SWIZ_BITS 8
+#define SWIZ_MASK ((1 << SWIZ_BITS) - 1)
+#define _oswiz(_type, _ind) ((_type << SWIZ_BITS) | (_ind & SWIZ_MASK))
+#define iswiz(_ind) (_ind >> SWIZ_BITS)
+
+static inline struct tmem_oid oswiz(unsigned type, u32 ind)
+{
+ struct tmem_oid oid = { .oid = { 0 } };
+ oid.oid[0] = _oswiz(type, ind);
+ return oid;
+}
+
+static int zcache_frontswap_put_page(unsigned type, pgoff_t offset,
+ struct page *page)
+{
+ u64 ind64 = (u64)offset;
+ u32 ind = (u32)offset;
+ struct tmem_oid oid = oswiz(type, ind);
+ int ret = -1;
+ unsigned long flags;
+ char *kva;
+
+ BUG_ON(!PageLocked(page));
+ if (likely(ind64 == ind)) {
+ local_irq_save(flags);
+ kva = page_address(page);
+ ret = zcache_put(LOCAL_CLIENT, zcache_frontswap_poolid,
+ &oid, iswiz(ind), kva, PAGE_SIZE, 0, 0);
+ local_irq_restore(flags);
+ }
+ return ret;
+}
+
+/* returns 0 if the page was successfully gotten from frontswap, -1 if
+ * was not present (should never happen!) */
+static int zcache_frontswap_get_page(unsigned type, pgoff_t offset,
+ struct page *page)
+{
+ u64 ind64 = (u64)offset;
+ u32 ind = (u32)offset;
+ struct tmem_oid oid = oswiz(type, ind);
+ int ret = -1;
+
+ preempt_disable(); /* FIXME, remove this? */
+ BUG_ON(!PageLocked(page));
+ if (likely(ind64 == ind)) {
+ char *kva = page_address(page);
+ size_t size = PAGE_SIZE;
+
+ ret = zcache_get(LOCAL_CLIENT, zcache_frontswap_poolid,
+ &oid, iswiz(ind), kva, &size, 0, -1);
+ }
+ preempt_enable(); /* FIXME, remove this? */
+ return ret;
+}
+
+/* flush a single page from frontswap */
+static void zcache_frontswap_flush_page(unsigned type, pgoff_t offset)
+{
+ u64 ind64 = (u64)offset;
+ u32 ind = (u32)offset;
+ struct tmem_oid oid = oswiz(type, ind);
+
+ if (likely(ind64 == ind))
+ (void)zcache_flush(LOCAL_CLIENT, zcache_frontswap_poolid,
+ &oid, iswiz(ind));
+}
+
+/* flush all pages from the passed swaptype */
+static void zcache_frontswap_flush_area(unsigned type)
+{
+ struct tmem_oid oid;
+ int ind;
+
+ for (ind = SWIZ_MASK; ind >= 0; ind--) {
+ oid = oswiz(type, ind);
+ (void)zcache_flush_object(LOCAL_CLIENT,
+ zcache_frontswap_poolid, &oid);
+ }
+}
+
+static void zcache_frontswap_init(unsigned ignored)
+{
+ /* a single tmem poolid is used for all frontswap "types" (swapfiles) */
+ if (zcache_frontswap_poolid < 0)
+ zcache_frontswap_poolid =
+ zcache_local_new_pool(TMEM_POOL_PERSIST);
+}
+
+static struct frontswap_ops zcache_frontswap_ops = {
+ .put_page = zcache_frontswap_put_page,
+ .get_page = zcache_frontswap_get_page,
+ .invalidate_page = zcache_frontswap_flush_page,
+ .invalidate_area = zcache_frontswap_flush_area,
+ .init = zcache_frontswap_init
+};
+
+struct frontswap_ops zcache_frontswap_register_ops(void)
+{
+ struct frontswap_ops old_ops =
+ frontswap_register_ops(&zcache_frontswap_ops);
+
+ return old_ops;
+}
+#endif
+
+/*
+ * frontswap selfshrinking
+ */
+
+#ifdef CONFIG_FRONTSWAP
+/* In HZ, controls frequency of worker invocation. */
+static unsigned int selfshrink_interval __read_mostly = 5;
+
+static void selfshrink_process(struct work_struct *work);
+static DECLARE_DELAYED_WORK(selfshrink_worker, selfshrink_process);
+
+/* Enable/disable with sysfs. */
+static bool frontswap_selfshrinking __read_mostly;
+
+/* Enable/disable with kernel boot option. */
+static bool use_frontswap_selfshrink __initdata = true;
+
+/*
+ * The default values for the following parameters were deemed reasonable
+ * by experimentation, may be workload-dependent, and can all be
+ * adjusted via sysfs.
+ */
+
+/* Control rate for frontswap shrinking. Higher hysteresis is slower. */
+static unsigned int frontswap_hysteresis __read_mostly = 20;
+
+/*
+ * Number of selfshrink worker invocations to wait before observing that
+ * frontswap selfshrinking should commence. Note that selfshrinking does
+ * not use a separate worker thread.
+ */
+static unsigned int frontswap_inertia __read_mostly = 3;
+
+/* Countdown to next invocation of frontswap_shrink() */
+static unsigned long frontswap_inertia_counter;
+
+/*
+ * Invoked by the selfshrink worker thread, uses current number of pages
+ * in frontswap (frontswap_curr_pages()), previous status, and control
+ * values (hysteresis and inertia) to determine if frontswap should be
+ * shrunk and what the new frontswap size should be. Note that
+ * frontswap_shrink is essentially a partial swapoff that immediately
+ * transfers pages from the "swap device" (frontswap) back into kernel
+ * RAM; despite the name, frontswap "shrinking" is very different from
+ * the "shrinker" interface used by the kernel MM subsystem to reclaim
+ * memory.
+ */
+static void frontswap_selfshrink(void)
+{
+ static unsigned long cur_frontswap_pages;
+ static unsigned long last_frontswap_pages;
+ static unsigned long tgt_frontswap_pages;
+
+ last_frontswap_pages = cur_frontswap_pages;
+ cur_frontswap_pages = frontswap_curr_pages();
+ if (!cur_frontswap_pages ||
+ (cur_frontswap_pages > last_frontswap_pages)) {
+ frontswap_inertia_counter = frontswap_inertia;
+ return;
+ }
+ if (frontswap_inertia_counter && --frontswap_inertia_counter)
+ return;
+ if (cur_frontswap_pages <= frontswap_hysteresis)
+ tgt_frontswap_pages = 0;
+ else
+ tgt_frontswap_pages = cur_frontswap_pages -
+ (cur_frontswap_pages / frontswap_hysteresis);
+ frontswap_shrink(tgt_frontswap_pages);
+}
+
+static int __init ramster_nofrontswap_selfshrink_setup(char *s)
+{
+ use_frontswap_selfshrink = false;
+ return 1;
+}
+
+__setup("noselfshrink", ramster_nofrontswap_selfshrink_setup);
+
+static void selfshrink_process(struct work_struct *work)
+{
+ if (frontswap_selfshrinking && frontswap_enabled) {
+ frontswap_selfshrink();
+ schedule_delayed_work(&selfshrink_worker,
+ selfshrink_interval * HZ);
+ }
+}
+
+static int ramster_enabled;
+
+static int __init ramster_selfshrink_init(void)
+{
+ frontswap_selfshrinking = ramster_enabled && use_frontswap_selfshrink;
+ if (frontswap_selfshrinking)
+ pr_info("ramster: Initializing frontswap "
+ "selfshrinking driver.\n");
+ else
+ return -ENODEV;
+
+ schedule_delayed_work(&selfshrink_worker, selfshrink_interval * HZ);
+
+ return 0;
+}
+
+subsys_initcall(ramster_selfshrink_init);
+#endif
+
+/*
+ * zcache initialization
+ * NOTE FOR NOW ramster MUST BE PROVIDED AS A KERNEL BOOT PARAMETER OR
+ * NOTHING HAPPENS!
+ */
+
+static int ramster_enabled;
+
+static int __init enable_ramster(char *s)
+{
+ ramster_enabled = 1;
+ return 1;
+}
+__setup("ramster", enable_ramster);
+
+/* allow independent dynamic disabling of cleancache and frontswap */
+
+static int use_cleancache = 1;
+
+static int __init no_cleancache(char *s)
+{
+ pr_info("INIT no_cleancache called\n");
+ use_cleancache = 0;
+ return 1;
+}
+
+/*
+ * FIXME: need to guarantee this gets checked before zcache_init is called
+ * What is the correct way to achieve this?
+ */
+early_param("nocleancache", no_cleancache);
+
+static int use_frontswap = 1;
+
+static int __init no_frontswap(char *s)
+{
+ pr_info("INIT no_frontswap called\n");
+ use_frontswap = 0;
+ return 1;
+}
+
+__setup("nofrontswap", no_frontswap);
+
+static int __init zcache_init(void)
+{
+ int ret = 0;
+
+#ifdef CONFIG_SYSFS
+ ret = sysfs_create_group(mm_kobj, &zcache_attr_group);
+ ret = sysfs_create_group(mm_kobj, &ramster_attr_group);
+ if (ret) {
+ pr_err("ramster: can't create sysfs\n");
+ goto out;
+ }
+#endif /* CONFIG_SYSFS */
+#if defined(CONFIG_CLEANCACHE) || defined(CONFIG_FRONTSWAP)
+ if (ramster_enabled) {
+ unsigned int cpu;
+
+ (void)r2net_register_handlers();
+ tmem_register_hostops(&zcache_hostops);
+ tmem_register_pamops(&zcache_pamops);
+ ret = register_cpu_notifier(&zcache_cpu_notifier_block);
+ if (ret) {
+ pr_err("ramster: can't register cpu notifier\n");
+ goto out;
+ }
+ for_each_online_cpu(cpu) {
+ void *pcpu = (void *)(long)cpu;
+ zcache_cpu_notifier(&zcache_cpu_notifier_block,
+ CPU_UP_PREPARE, pcpu);
+ }
+ }
+ zcache_objnode_cache = kmem_cache_create("zcache_objnode",
+ sizeof(struct tmem_objnode), 0, 0, NULL);
+ zcache_obj_cache = kmem_cache_create("zcache_obj",
+ sizeof(struct tmem_obj), 0, 0, NULL);
+ ramster_flnode_cache = kmem_cache_create("ramster_flnode",
+ sizeof(struct flushlist_node), 0, 0, NULL);
+#endif
+#ifdef CONFIG_CLEANCACHE
+ pr_info("INIT ramster_enabled=%d use_cleancache=%d\n",
+ ramster_enabled, use_cleancache);
+ if (ramster_enabled && use_cleancache) {
+ struct cleancache_ops old_ops;
+
+ zbud_init();
+ register_shrinker(&zcache_shrinker);
+ old_ops = zcache_cleancache_register_ops();
+ pr_info("ramster: cleancache enabled using kernel "
+ "transcendent memory and compression buddies\n");
+ if (old_ops.init_fs != NULL)
+ pr_warning("ramster: cleancache_ops overridden");
+ }
+#endif
+#ifdef CONFIG_FRONTSWAP
+ pr_info("INIT ramster_enabled=%d use_frontswap=%d\n",
+ ramster_enabled, use_frontswap);
+ if (ramster_enabled && use_frontswap) {
+ struct frontswap_ops old_ops;
+
+ zcache_new_client(LOCAL_CLIENT);
+ old_ops = zcache_frontswap_register_ops();
+ pr_info("ramster: frontswap enabled using kernel "
+ "transcendent memory and xvmalloc\n");
+ if (old_ops.init != NULL)
+ pr_warning("ramster: frontswap_ops overridden");
+ }
+ if (ramster_enabled && (use_frontswap || use_cleancache))
+ ramster_remotify_init();
+#endif
+out:
+ return ret;
+}
+
+module_init(zcache_init)
projects / linux-flexiantxendom0-3.2.10.git / commitdiff