1 files changed, 21 insertions, 17 deletions

diff --git a/mm/shmem.c b/mm/shmem.c
index 5a0b3d4055f3..356dd99566ec 100644
--- a/mm/shmem.c
+++ b/mm/shmem.c
@@ -49,7 +49,6 @@ static struct vfsmount *shm_mnt;
 #include <linux/backing-dev.h>
 #include <linux/shmem_fs.h>
 #include <linux/writeback.h>
-#include <linux/vfs.h>
 #include <linux/blkdev.h>
 #include <linux/security.h>
 #include <linux/swapops.h>
@@ -219,7 +218,7 @@ static const struct file_operations shmem_file_operations;
 static const struct inode_operations shmem_inode_operations;
 static const struct inode_operations shmem_dir_inode_operations;
 static const struct inode_operations shmem_special_inode_operations;
-static struct vm_operations_struct shmem_vm_ops;
+static const struct vm_operations_struct shmem_vm_ops;
 
 static struct backing_dev_info shmem_backing_dev_info  __read_mostly = {
         .ra_pages       = 0,    /* No readahead */
@@ -1047,8 +1046,9 @@ static int shmem_writepage(struct page *page, struct writeback_control *wbc)
          * sync from ever calling shmem_writepage; but a stacking filesystem
          * may use the ->writepage of its underlying filesystem, in which case
          * tmpfs should write out to swap only in response to memory pressure,
-         * and not for pdflush or sync.  However, in those cases, we do still
-         * want to check if there's a redundant swappage to be discarded.
+         * and not for the writeback threads or sync.  However, in those cases,
+         * we do still want to check if there's a redundant swappage to be
+         * discarded.
          */
         if (wbc->for_reclaim)
                 swap = get_swap_page();
@@ -1097,6 +1097,10 @@ static int shmem_writepage(struct page *page, struct writeback_control *wbc)
         shmem_swp_unmap(entry);
 unlock:
         spin_unlock(&info->lock);
+        /*
+         * add_to_swap_cache() doesn't return -EEXIST, so we can safely
+         * clear SWAP_HAS_CACHE flag.
+         */
         swapcache_free(swap, NULL);
 redirty:
         set_page_dirty(page);
@@ -1630,8 +1634,8 @@ shmem_write_end(struct file *file, struct address_space *mapping,
         if (pos + copied > inode->i_size)
                 i_size_write(inode, pos + copied);
 
-        unlock_page(page);
         set_page_dirty(page);
+        unlock_page(page);
         page_cache_release(page);
 
         return copied;
@@ -1968,13 +1972,13 @@ static int shmem_symlink(struct inode *dir, struct dentry *dentry, const char *s
                         iput(inode);
                         return error;
                 }
-                unlock_page(page);
                 inode->i_mapping->a_ops = &shmem_aops;
                 inode->i_op = &shmem_symlink_inode_operations;
                 kaddr = kmap_atomic(page, KM_USER0);
                 memcpy(kaddr, symname, len);
                 kunmap_atomic(kaddr, KM_USER0);
                 set_page_dirty(page);
+                unlock_page(page);
                 page_cache_release(page);
         }
         if (dir->i_mode & S_ISGID)
@@ -2298,8 +2302,7 @@ static void shmem_put_super(struct super_block *sb)
         sb->s_fs_info = NULL;
 }
 
-static int shmem_fill_super(struct super_block *sb,
-                            void *data, int silent)
+int shmem_fill_super(struct super_block *sb, void *data, int silent)
 {
         struct inode *inode;
         struct dentry *root;
@@ -2307,17 +2310,14 @@ static int shmem_fill_super(struct super_block *sb,
         int err = -ENOMEM;
 
         /* Round up to L1_CACHE_BYTES to resist false sharing */
-        sbinfo = kmalloc(max((int)sizeof(struct shmem_sb_info),
+        sbinfo = kzalloc(max((int)sizeof(struct shmem_sb_info),
                                 L1_CACHE_BYTES), GFP_KERNEL);
         if (!sbinfo)
                 return -ENOMEM;
 
-        sbinfo->max_blocks = 0;
-        sbinfo->max_inodes = 0;
         sbinfo->mode = S_IRWXUGO | S_ISVTX;
         sbinfo->uid = current_fsuid();
         sbinfo->gid = current_fsgid();
-        sbinfo->mpol = NULL;
         sb->s_fs_info = sbinfo;
 
 #ifdef CONFIG_TMPFS
@@ -2421,6 +2421,7 @@ static const struct address_space_operations shmem_aops = {
         .write_end      = shmem_write_end,
 #endif
         .migratepage    = migrate_page,
+        .error_remove_page = generic_error_remove_page,
 };
 
 static const struct file_operations shmem_file_operations = {
@@ -2497,7 +2498,7 @@ static const struct super_operations shmem_ops = {
         .put_super      = shmem_put_super,
 };
 
-static struct vm_operations_struct shmem_vm_ops = {
+static const struct vm_operations_struct shmem_vm_ops = {
         .fault          = shmem_fault,
 #ifdef CONFIG_NUMA
         .set_policy     = shmem_set_policy,
@@ -2519,7 +2520,7 @@ static struct file_system_type tmpfs_fs_type = {
         .kill_sb        = kill_litter_super,
 };
 
-static int __init init_tmpfs(void)
+int __init init_tmpfs(void)
 {
         int error;
 
@@ -2576,7 +2577,7 @@ static struct file_system_type tmpfs_fs_type = {
         .kill_sb        = kill_litter_super,
 };
 
-static int __init init_tmpfs(void)
+int __init init_tmpfs(void)
 {
         BUG_ON(register_filesystem(&tmpfs_fs_type) != 0);
 
@@ -2591,6 +2592,11 @@ int shmem_unuse(swp_entry_t entry, struct page *page)
         return 0;
 }
 
+int shmem_lock(struct file *file, int lock, struct user_struct *user)
+{
+        return 0;
+}
+
 #define shmem_vm_ops                            generic_file_vm_ops
 #define shmem_file_operations                   ramfs_file_operations
 #define shmem_get_inode(sb, mode, dev, flags)   ramfs_get_inode(sb, mode, dev)
@@ -2687,5 +2693,3 @@ int shmem_zero_setup(struct vm_area_struct *vma)
         vma->vm_ops = &shmem_vm_ops;
         return 0;
 }
-
-module_init(init_tmpfs)