UBIFS: fix bug where page is marked uptodate when out of space

[linux-2.6-omap-h63xx.git] / fs / ubifs / file.c

diff --git a/fs/ubifs/file.c b/fs/ubifs/file.c
index 2624411d9758d11023c938418f8a6a7938066ff5..4e7f0aca9ebcc7917050c0c256c79b87cf60c6fe 100644 (file)
--- a/fs/ubifs/file.c
+++ b/fs/ubifs/file.c
@@ -72,8 +72,8 @@ static int read_block(struct inode *inode, void *addr, unsigned int block,
                return err;
        }
 
-       ubifs_assert(le64_to_cpu(dn->ch.sqnum) > ubifs_inode(inode)->creat_sqnum);
-
+       ubifs_assert(le64_to_cpu(dn->ch.sqnum) >
+                    ubifs_inode(inode)->creat_sqnum);
        len = le32_to_cpu(dn->size);
        if (len <= 0 || len > UBIFS_BLOCK_SIZE)
                goto dump;
@@ -219,7 +219,8 @@ static void release_existing_page_budget(struct ubifs_info *c)
 }
 
 static int write_begin_slow(struct address_space *mapping,
-                           loff_t pos, unsigned len, struct page **pagep)
+                           loff_t pos, unsigned len, struct page **pagep,
+                           unsigned flags)
 {
        struct inode *inode = mapping->host;
        struct ubifs_info *c = inode->i_sb->s_fs_info;
@@ -247,14 +248,14 @@ static int write_begin_slow(struct address_space *mapping,
        if (unlikely(err))
                return err;
 
-       page = __grab_cache_page(mapping, index);
+       page = grab_cache_page_write_begin(mapping, index, flags);
        if (unlikely(!page)) {
                ubifs_release_budget(c, &req);
                return -ENOMEM;
        }
 
        if (!PageUptodate(page)) {
-               if (!(pos & PAGE_CACHE_MASK) && len == PAGE_CACHE_SIZE)
+               if (!(pos & ~PAGE_CACHE_MASK) && len == PAGE_CACHE_SIZE)
                        SetPageChecked(page);
                else {
                        err = do_readpage(page);
@@ -429,22 +430,22 @@ static int ubifs_write_begin(struct file *file, struct address_space *mapping,
        struct ubifs_inode *ui = ubifs_inode(inode);
        pgoff_t index = pos >> PAGE_CACHE_SHIFT;
        int uninitialized_var(err), appending = !!(pos + len > inode->i_size);
+       int skipped_read = 0;
        struct page *page;
 
-
        ubifs_assert(ubifs_inode(inode)->ui_size == inode->i_size);
 
        if (unlikely(c->ro_media))
                return -EROFS;
 
        /* Try out the fast-path part first */
-       page = __grab_cache_page(mapping, index);
+       page = grab_cache_page_write_begin(mapping, index, flags);
        if (unlikely(!page))
                return -ENOMEM;
 
        if (!PageUptodate(page)) {
                /* The page is not loaded from the flash */
-               if (!(pos & PAGE_CACHE_MASK) && len == PAGE_CACHE_SIZE)
+               if (!(pos & ~PAGE_CACHE_MASK) && len == PAGE_CACHE_SIZE) {
                        /*
                         * We change whole page so no need to load it. But we
                         * have to set the @PG_checked flag to make the further
@@ -453,7 +454,8 @@ static int ubifs_write_begin(struct file *file, struct address_space *mapping,
                         * the media.
                         */
                        SetPageChecked(page);
-               else {
+                       skipped_read = 1;
+               } else {
                        err = do_readpage(page);
                        if (err) {
                                unlock_page(page);
@@ -469,6 +471,14 @@ static int ubifs_write_begin(struct file *file, struct address_space *mapping,
        err = allocate_budget(c, page, ui, appending);
        if (unlikely(err)) {
                ubifs_assert(err == -ENOSPC);
+               /*
+                * If we skipped reading the page because we were going to
+                * write all of it, then it is not up to date.
+                */
+               if (skipped_read) {
+                       ClearPageChecked(page);
+                       ClearPageUptodate(page);
+               }
                /*
                 * Budgeting failed which means it would have to force
                 * write-back but didn't, because we set the @fast flag in the
@@ -483,7 +493,7 @@ static int ubifs_write_begin(struct file *file, struct address_space *mapping,
                unlock_page(page);
                page_cache_release(page);
 
-               return write_begin_slow(mapping, pos, len, pagep);
+               return write_begin_slow(mapping, pos, len, pagep, flags);
        }
 
        /*
@@ -1540,7 +1550,7 @@ static int ubifs_file_mmap(struct file *file, struct vm_area_struct *vma)
        return 0;
 }
 
-struct address_space_operations ubifs_file_address_operations = {
+const struct address_space_operations ubifs_file_address_operations = {
        .readpage       = ubifs_readpage,
        .writepage      = ubifs_writepage,
        .write_begin    = ubifs_write_begin,
@@ -1550,7 +1560,7 @@ struct address_space_operations ubifs_file_address_operations = {
        .releasepage    = ubifs_releasepage,
 };
 
-struct inode_operations ubifs_file_inode_operations = {
+const struct inode_operations ubifs_file_inode_operations = {
        .setattr     = ubifs_setattr,
        .getattr     = ubifs_getattr,
 #ifdef CONFIG_UBIFS_FS_XATTR
@@ -1561,14 +1571,14 @@ struct inode_operations ubifs_file_inode_operations = {
 #endif
 };
 
-struct inode_operations ubifs_symlink_inode_operations = {
+const struct inode_operations ubifs_symlink_inode_operations = {
        .readlink    = generic_readlink,
        .follow_link = ubifs_follow_link,
        .setattr     = ubifs_setattr,
        .getattr     = ubifs_getattr,
 };
 
-struct file_operations ubifs_file_operations = {
+const struct file_operations ubifs_file_operations = {
        .llseek         = generic_file_llseek,
        .read           = do_sync_read,
        .write          = do_sync_write,