const: mark struct vm_struct_operations
[linux-2.6.git] / mm / shmem.c
index 0132fbd..356dd99 100644 (file)
@@ -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();
@@ -1097,7 +1097,11 @@ static int shmem_writepage(struct page *page, struct writeback_control *wbc)
        shmem_swp_unmap(entry);
 unlock:
        spin_unlock(&info->lock);
-       swap_free(swap);
+       /*
+        * 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);
        if (wbc->for_reclaim)
@@ -1558,6 +1562,7 @@ static struct inode *shmem_get_inode(struct super_block *sb, int mode,
                spin_lock_init(&info->lock);
                info->flags = flags & VM_NORESERVE;
                INIT_LIST_HEAD(&info->swaplist);
+               cache_no_acl(inode);
 
                switch (mode & S_IFMT) {
                default:
@@ -1629,8 +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;
@@ -1967,13 +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)
@@ -2297,8 +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;
@@ -2306,17 +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
@@ -2388,7 +2389,6 @@ static void shmem_destroy_inode(struct inode *inode)
                /* only struct inode is valid if it's an inline symlink */
                mpol_free_shared_policy(&SHMEM_I(inode)->policy);
        }
-       shmem_acl_destroy_inode(inode);
        kmem_cache_free(shmem_inode_cachep, SHMEM_I(inode));
 }
 
@@ -2397,10 +2397,6 @@ static void init_once(void *foo)
        struct shmem_inode_info *p = (struct shmem_inode_info *) foo;
 
        inode_init_once(&p->vfs_inode);
-#ifdef CONFIG_TMPFS_POSIX_ACL
-       p->i_acl = NULL;
-       p->i_default_acl = NULL;
-#endif
 }
 
 static int init_inodecache(void)
@@ -2425,6 +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 = {
@@ -2450,7 +2447,7 @@ static const struct inode_operations shmem_inode_operations = {
        .getxattr       = generic_getxattr,
        .listxattr      = generic_listxattr,
        .removexattr    = generic_removexattr,
-       .permission     = shmem_permission,
+       .check_acl      = shmem_check_acl,
 #endif
 
 };
@@ -2473,7 +2470,7 @@ static const struct inode_operations shmem_dir_inode_operations = {
        .getxattr       = generic_getxattr,
        .listxattr      = generic_listxattr,
        .removexattr    = generic_removexattr,
-       .permission     = shmem_permission,
+       .check_acl      = shmem_check_acl,
 #endif
 };
 
@@ -2484,7 +2481,7 @@ static const struct inode_operations shmem_special_inode_operations = {
        .getxattr       = generic_getxattr,
        .listxattr      = generic_listxattr,
        .removexattr    = generic_removexattr,
-       .permission     = shmem_permission,
+       .check_acl      = shmem_check_acl,
 #endif
 };
 
@@ -2501,7 +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,
@@ -2523,7 +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;
 
@@ -2580,7 +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);
 
@@ -2595,6 +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)
@@ -2612,7 +2614,7 @@ int shmem_unuse(swp_entry_t entry, struct page *page)
  * @size: size to be set for the file
  * @flags: VM_NORESERVE suppresses pre-accounting of the entire object size
  */
-struct file *shmem_file_setup(char *name, loff_t size, unsigned long flags)
+struct file *shmem_file_setup(const char *name, loff_t size, unsigned long flags)
 {
        int error;
        struct file *file;
@@ -2691,5 +2693,3 @@ int shmem_zero_setup(struct vm_area_struct *vma)
        vma->vm_ops = &shmem_vm_ops;
        return 0;
 }
-
-module_init(init_tmpfs)