- patches.suse/slab-handle-memoryless-nodes-v2a.patch: Refresh.

[linux-flexiantxendom0-3.2.10.git] / arch / um / drivers / mconsole_kern.c

diff --git a/arch/um/drivers/mconsole_kern.c b/arch/um/drivers/mconsole_kern.c
index e14629c..3b3c366 100644 (file)
--- a/arch/um/drivers/mconsole_kern.c
+++ b/arch/um/drivers/mconsole_kern.c
@@ -6,6 +6,7 @@
 
 #include <linux/console.h>
 #include <linux/ctype.h>
+#include <linux/string.h>
 #include <linux/interrupt.h>
 #include <linux/list.h>
 #include <linux/mm.h>
@@ -124,50 +125,36 @@ void mconsole_log(struct mc_request *req)
 void mconsole_proc(struct mc_request *req)
 {
        struct nameidata nd;
-       struct file_system_type *proc;
-       struct super_block *super;
+       struct vfsmount *mnt = current->nsproxy->pid_ns->proc_mnt;
        struct file *file;
        int n, err;
        char *ptr = req->request.data, *buf;
+       mm_segment_t old_fs = get_fs();
 
        ptr += strlen("proc");
-       while (isspace(*ptr)) ptr++;
+       ptr = skip_spaces(ptr);
 
-       proc = get_fs_type("proc");
-       if (proc == NULL) {
-               mconsole_reply(req, "procfs not registered", 1, 0);
+       err = vfs_path_lookup(mnt->mnt_root, mnt, ptr, LOOKUP_FOLLOW, &nd);
+       if (err) {
+               mconsole_reply(req, "Failed to look up file", 1, 0);
                goto out;
        }
 
-       super = (*proc->get_sb)(proc, 0, NULL, NULL);
-       put_filesystem(proc);
-       if (super == NULL) {
-               mconsole_reply(req, "Failed to get procfs superblock", 1, 0);
+       err = may_open(&nd.path, MAY_READ, FMODE_READ);
+       if (result) {
+               mconsole_reply(req, "Failed to open file", 1, 0);
+               path_put(&nd.path);
                goto out;
        }
-       up_write(&super->s_umount);
-
-       nd.path.dentry = super->s_root;
-       nd.path.mnt = NULL;
-       nd.flags = O_RDONLY + 1;
-       nd.last_type = LAST_ROOT;
-
-       /* START: it was experienced that the stability problems are closed
-        * if commenting out these two calls + the below read cycle. To
-        * make UML crash again, it was enough to readd either one.*/
-       err = link_path_walk(ptr, &nd);
-       if (err) {
-               mconsole_reply(req, "Failed to look up file", 1, 0);
-               goto out_kill;
-       }
 
        file = dentry_open(nd.path.dentry, nd.path.mnt, O_RDONLY,
                           current_cred());
+       err = PTR_ERR(file);
        if (IS_ERR(file)) {
                mconsole_reply(req, "Failed to open file", 1, 0);
-               goto out_kill;
+               path_put(&nd.path);
+               goto out;
        }
-       /*END*/
 
        buf = kmalloc(PAGE_SIZE, GFP_KERNEL);
        if (buf == NULL) {
@@ -175,10 +162,13 @@ void mconsole_proc(struct mc_request *req)
                goto out_fput;
        }
 
-       if ((file->f_op != NULL) && (file->f_op->read != NULL)) {
+       if (file->f_op->read) {
                do {
-                       n = (*file->f_op->read)(file, buf, PAGE_SIZE - 1,
-                                               &file->f_pos);
+                       loff_t pos;
+                       set_fs(KERNEL_DS);
+                       n = vfs_read(file, buf, PAGE_SIZE - 1, &pos);
+                       file_pos_write(file, pos);
+                       set_fs(old_fs);
                        if (n >= 0) {
                                buf[n] = '\0';
                                mconsole_reply(req, buf, 0, (n > 0));
@@ -196,8 +186,6 @@ void mconsole_proc(struct mc_request *req)
        kfree(buf);
  out_fput:
        fput(file);
- out_kill:
-       deactivate_super(super);
  out: ;
 }
 #endif
@@ -212,8 +200,7 @@ void mconsole_proc(struct mc_request *req)
        char *ptr = req->request.data;
 
        ptr += strlen("proc");
-       while (isspace(*ptr))
-               ptr++;
+       ptr = skip_spaces(ptr);
        snprintf(path, sizeof(path), "/proc/%s", ptr);
 
        fd = sys_open(path, 0, 0);
@@ -560,8 +547,7 @@ void mconsole_config(struct mc_request *req)
        int err;
 
        ptr += strlen("config");
-       while (isspace(*ptr))
-               ptr++;
+       ptr = skip_spaces(ptr);
        dev = mconsole_find_dev(ptr);
        if (dev == NULL) {
                mconsole_reply(req, "Bad configuration option", 1, 0);
@@ -588,7 +574,7 @@ void mconsole_remove(struct mc_request *req)
        int err, start, end, n;
 
        ptr += strlen("remove");
-       while (isspace(*ptr)) ptr++;
+       ptr = skip_spaces(ptr);
        dev = mconsole_find_dev(ptr);
        if (dev == NULL) {
                mconsole_reply(req, "Bad remove option", 1, 0);
@@ -712,7 +698,7 @@ void mconsole_sysrq(struct mc_request *req)
        char *ptr = req->request.data;
 
        ptr += strlen("sysrq");
-       while (isspace(*ptr)) ptr++;
+       ptr = skip_spaces(ptr);
 
        /*
         * With 'b', the system will shut down without a chance to reply,
@@ -757,8 +743,7 @@ void mconsole_stack(struct mc_request *req)
         */
 
        ptr += strlen("stack");
-       while (isspace(*ptr))
-               ptr++;
+       ptr = skip_spaces(ptr);
 
        /*
         * Should really check for multiple pids or reject bad args here
@@ -833,8 +818,8 @@ static int __init mconsole_init(void)
 
 __initcall(mconsole_init);
 
-static int write_proc_mconsole(struct file *file, const char __user *buffer,
-                              unsigned long count, void *data)
+static ssize_t mconsole_proc_write(struct file *file,
+               const char __user *buffer, size_t count, loff_t *pos)
 {
        char *buf;
 
@@ -855,6 +840,11 @@ static int write_proc_mconsole(struct file *file, const char __user *buffer,
        return count;
 }
 
+static const struct file_operations mconsole_proc_fops = {
+       .owner          = THIS_MODULE,
+       .write          = mconsole_proc_write,
+};
+
 static int create_proc_mconsole(void)
 {
        struct proc_dir_entry *ent;
@@ -862,15 +852,12 @@ static int create_proc_mconsole(void)
        if (notify_socket == NULL)
                return 0;
 
-       ent = create_proc_entry("mconsole", S_IFREG | 0200, NULL);
+       ent = proc_create("mconsole", 0200, NULL, &mconsole_proc_fops);
        if (ent == NULL) {
                printk(KERN_INFO "create_proc_mconsole : create_proc_entry "
                       "failed\n");
                return 0;
        }
-
-       ent->read_proc = NULL;
-       ent->write_proc = write_proc_mconsole;
        return 0;
 }