diff options
Diffstat (limited to 'fs/ext4/inline.c')
| -rw-r--r-- | fs/ext4/inline.c | 233 |
1 files changed, 233 insertions, 0 deletions
diff --git a/fs/ext4/inline.c b/fs/ext4/inline.c index e4a41d5d06d..320ff6fe5d8 100644 --- a/fs/ext4/inline.c +++ b/fs/ext4/inline.c @@ -14,6 +14,7 @@ #include "ext4_jbd2.h" #include "ext4.h" #include "xattr.h" +#include "truncate.h" #define EXT4_XATTR_SYSTEM_DATA "data" #define EXT4_MIN_INLINE_DATA_SIZE ((sizeof(__le32) * EXT4_N_BLOCKS)) @@ -515,6 +516,238 @@ int ext4_readpage_inline(struct inode *inode, struct page *page) return ret >= 0 ? 0 : ret; } +static int ext4_convert_inline_data_to_extent(struct address_space *mapping, + struct inode *inode, + unsigned flags) +{ + int ret, needed_blocks; + handle_t *handle = NULL; + int retries = 0, sem_held = 0; + struct page *page = NULL; + unsigned from, to; + struct ext4_iloc iloc; + + if (!ext4_has_inline_data(inode)) { + /* + * clear the flag so that no new write + * will trap here again. + */ + ext4_clear_inode_state(inode, EXT4_STATE_MAY_INLINE_DATA); + return 0; + } + + needed_blocks = ext4_writepage_trans_blocks(inode); + + ret = ext4_get_inode_loc(inode, &iloc); + if (ret) + return ret; + +retry: + handle = ext4_journal_start(inode, needed_blocks); + if (IS_ERR(handle)) { + ret = PTR_ERR(handle); + handle = NULL; + goto out; + } + + /* We cannot recurse into the filesystem as the transaction is already + * started */ + flags |= AOP_FLAG_NOFS; + + page = grab_cache_page_write_begin(mapping, 0, flags); + if (!page) { + ret = -ENOMEM; + goto out; + } + + down_write(&EXT4_I(inode)->xattr_sem); + sem_held = 1; + /* If some one has already done this for us, just exit. */ + if (!ext4_has_inline_data(inode)) { + ret = 0; + goto out; + } + + from = 0; + to = ext4_get_inline_size(inode); + if (!PageUptodate(page)) { + ret = ext4_read_inline_page(inode, page); + if (ret < 0) + goto out; + } + + ret = ext4_destroy_inline_data_nolock(handle, inode); + if (ret) + goto out; + + if (ext4_should_dioread_nolock(inode)) + ret = __block_write_begin(page, from, to, ext4_get_block_write); + else + ret = __block_write_begin(page, from, to, ext4_get_block); + + if (!ret && ext4_should_journal_data(inode)) { + ret = ext4_walk_page_buffers(handle, page_buffers(page), + from, to, NULL, + do_journal_get_write_access); + } + + if (ret) { + unlock_page(page); + page_cache_release(page); + ext4_orphan_add(handle, inode); + up_write(&EXT4_I(inode)->xattr_sem); + sem_held = 0; + ext4_journal_stop(handle); + handle = NULL; + ext4_truncate_failed_write(inode); + /* + * If truncate failed early the inode might + * still be on the orphan list; we need to + * make sure the inode is removed from the + * orphan list in that case. + */ + if (inode->i_nlink) + ext4_orphan_del(NULL, inode); + } + + if (ret == -ENOSPC && ext4_should_retry_alloc(inode->i_sb, &retries)) + goto retry; + + block_commit_write(page, from, to); +out: + if (page) { + unlock_page(page); + page_cache_release(page); + } + if (sem_held) + up_write(&EXT4_I(inode)->xattr_sem); + if (handle) + ext4_journal_stop(handle); + brelse(iloc.bh); + return ret; +} + +/* + * Try to write data in the inode. + * If the inode has inline data, check whether the new write can be + * in the inode also. If not, create the page the handle, move the data + * to the page make it update and let the later codes create extent for it. + */ +int ext4_try_to_write_inline_data(struct address_space *mapping, + struct inode *inode, + loff_t pos, unsigned len, + unsigned flags, + struct page **pagep) +{ + int ret; + handle_t *handle; + struct page *page; + struct ext4_iloc iloc; + + if (pos + len > ext4_get_max_inline_size(inode)) + goto convert; + + ret = ext4_get_inode_loc(inode, &iloc); + if (ret) + return ret; + + /* + * The possible write could happen in the inode, + * so try to reserve the space in inode first. + */ + handle = ext4_journal_start(inode, 1); + if (IS_ERR(handle)) { + ret = PTR_ERR(handle); + handle = NULL; + goto out; + } + + ret = ext4_prepare_inline_data(handle, inode, pos + len); + if (ret && ret != -ENOSPC) + goto out; + + /* We don't have space in inline inode, so convert it to extent. */ + if (ret == -ENOSPC) { + ext4_journal_stop(handle); + brelse(iloc.bh); + goto convert; + } + + flags |= AOP_FLAG_NOFS; + + page = grab_cache_page_write_begin(mapping, 0, flags); + if (!page) { + ret = -ENOMEM; + goto out; + } + + *pagep = page; + down_read(&EXT4_I(inode)->xattr_sem); + if (!ext4_has_inline_data(inode)) { + ret = 0; + unlock_page(page); + page_cache_release(page); + goto out_up_read; + } + + if (!PageUptodate(page)) { + ret = ext4_read_inline_page(inode, page); + if (ret < 0) + goto out_up_read; + } + + ret = 1; + handle = NULL; +out_up_read: + up_read(&EXT4_I(inode)->xattr_sem); +out: + if (handle) + ext4_journal_stop(handle); + brelse(iloc.bh); + return ret; +convert: + return ext4_convert_inline_data_to_extent(mapping, + inode, flags); +} + +int ext4_write_inline_data_end(struct inode *inode, loff_t pos, unsigned len, + unsigned copied, struct page *page) +{ + int ret; + void *kaddr; + struct ext4_iloc iloc; + + if (unlikely(copied < len)) { + if (!PageUptodate(page)) { + copied = 0; + goto out; + } + } + + ret = ext4_get_inode_loc(inode, &iloc); + if (ret) { + ext4_std_error(inode->i_sb, ret); + copied = 0; + goto out; + } + + down_write(&EXT4_I(inode)->xattr_sem); + BUG_ON(!ext4_has_inline_data(inode)); + + kaddr = kmap_atomic(page); + ext4_write_inline_data(inode, &iloc, kaddr, pos, len); + kunmap_atomic(kaddr); + SetPageUptodate(page); + /* clear page dirty so that writepages wouldn't work for us. */ + ClearPageDirty(page); + + up_write(&EXT4_I(inode)->xattr_sem); + brelse(iloc.bh); +out: + return copied; +} + + int ext4_destroy_inline_data(handle_t *handle, struct inode *inode) { int ret; |