The nobh option was only supported for writeback mode, but given that all write paths actually create buffer heads it effectively was a no-op already. Signed-off-by: Christoph Hellwig <hch@xxxxxx> Index: linux-2.6/fs/ext4/ext4.h =================================================================== --- linux-2.6.orig/fs/ext4/ext4.h 2010-06-07 09:51:34.661025144 +0200 +++ linux-2.6/fs/ext4/ext4.h 2010-06-07 09:51:41.198255687 +0200 @@ -873,7 +873,6 @@ struct ext4_inode_info { #define EXT4_MOUNT_POSIX_ACL 0x08000 /* POSIX Access Control Lists */ #define EXT4_MOUNT_NO_AUTO_DA_ALLOC 0x10000 /* No auto delalloc mapping */ #define EXT4_MOUNT_BARRIER 0x20000 /* Use block barriers */ -#define EXT4_MOUNT_NOBH 0x40000 /* No bufferheads */ #define EXT4_MOUNT_QUOTA 0x80000 /* Some quota option set */ #define EXT4_MOUNT_USRQUOTA 0x100000 /* "old" user quota */ #define EXT4_MOUNT_GRPQUOTA 0x200000 /* "old" group quota */ Index: linux-2.6/fs/ext4/ext4_jbd2.h =================================================================== --- linux-2.6.orig/fs/ext4/ext4_jbd2.h 2010-06-07 09:49:29.688025631 +0200 +++ linux-2.6/fs/ext4/ext4_jbd2.h 2010-06-07 09:51:28.450657504 +0200 @@ -308,17 +308,15 @@ static inline int ext4_should_writeback_ * This function controls whether or not we should try to go down the * dioread_nolock code paths, which makes it safe to avoid taking * i_mutex for direct I/O reads. This only works for extent-based - * files, and it doesn't work for nobh or if data journaling is - * enabled, since the dioread_nolock code uses b_private to pass - * information back to the I/O completion handler, and this conflicts - * with the jbd's use of b_private. + * files, and it doesn't work if data journaling is enabled, since the + * dioread_nolock code uses b_private to pass information back to the + * I/O completion handler, and this conflicts with the jbd's use of + * b_private. */ static inline int ext4_should_dioread_nolock(struct inode *inode) { if (!test_opt(inode->i_sb, DIOREAD_NOLOCK)) return 0; - if (test_opt(inode->i_sb, NOBH)) - return 0; if (!S_ISREG(inode->i_mode)) return 0; if (!(ext4_test_inode_flag(inode, EXT4_INODE_EXTENTS))) Index: linux-2.6/fs/ext4/inode.c =================================================================== --- linux-2.6.orig/fs/ext4/inode.c 2010-06-07 09:50:05.392262188 +0200 +++ linux-2.6/fs/ext4/inode.c 2010-06-07 09:51:10.154255343 +0200 @@ -2553,18 +2553,16 @@ static int ext4_da_get_block_prep(struct /* * This function is used as a standard get_block_t calback function * when there is no desire to allocate any blocks. It is used as a - * callback function for block_prepare_write(), nobh_writepage(), and - * block_write_full_page(). These functions should only try to map a - * single block at a time. + * callback function for block_prepare_write() and block_write_full_page(). + * These functions should only try to map a single block at a time. * * Since this function doesn't do block allocations even if the caller * requests it by passing in create=1, it is critically important that * any caller checks to make sure that any buffer heads are returned * by this function are either all already mapped or marked for - * delayed allocation before calling nobh_writepage() or - * block_write_full_page(). Otherwise, b_blocknr could be left - * unitialized, and the page write functions will be taken by - * surprise. + * delayed allocation before calling block_write_full_page(). Otherwise, + * b_blocknr could be left unitialized, and the page write functions will + * be taken by surprise. */ static int noalloc_get_block_write(struct inode *inode, sector_t iblock, struct buffer_head *bh_result, int create) @@ -2749,9 +2747,7 @@ static int ext4_writepage(struct page *p return __ext4_journalled_writepage(page, len); } - if (test_opt(inode->i_sb, NOBH) && ext4_should_writeback_data(inode)) - ret = nobh_writepage(page, noalloc_get_block_write, wbc); - else if (page_bufs && buffer_uninit(page_bufs)) { + if (page_bufs && buffer_uninit(page_bufs)) { ext4_set_bh_endio(page_bufs, inode); ret = block_write_full_page_endio(page, noalloc_get_block_write, wbc, ext4_end_io_buffer_write); @@ -4128,17 +4124,6 @@ int ext4_block_truncate_page(handle_t *h length = blocksize - (offset & (blocksize - 1)); iblock = index << (PAGE_CACHE_SHIFT - inode->i_sb->s_blocksize_bits); - /* - * For "nobh" option, we can only work if we don't need to - * read-in the page - otherwise we create buffers to do the IO. - */ - if (!page_has_buffers(page) && test_opt(inode->i_sb, NOBH) && - ext4_should_writeback_data(inode) && PageUptodate(page)) { - zero_user(page, offset, length); - set_page_dirty(page); - goto unlock; - } - if (!page_has_buffers(page)) create_empty_buffers(page, blocksize, 0); Index: linux-2.6/fs/ext4/super.c =================================================================== --- linux-2.6.orig/fs/ext4/super.c 2010-06-07 09:51:46.013275620 +0200 +++ linux-2.6/fs/ext4/super.c 2010-06-07 09:53:17.975255390 +0200 @@ -946,8 +946,6 @@ static int ext4_show_options(struct seq_ seq_puts(seq, ",journal_async_commit"); else if (test_opt(sb, JOURNAL_CHECKSUM)) seq_puts(seq, ",journal_checksum"); - if (test_opt(sb, NOBH)) - seq_puts(seq, ",nobh"); if (test_opt(sb, I_VERSION)) seq_puts(seq, ",i_version"); if (!test_opt(sb, DELALLOC)) @@ -1624,10 +1622,12 @@ set_qf_format: *n_blocks_count = option; break; case Opt_nobh: - set_opt(sbi->s_mount_opt, NOBH); + ext4_msg(sb, KERN_WARNING, + "Ignoring deprecated nobh option"); break; case Opt_bh: - clear_opt(sbi->s_mount_opt, NOBH); + ext4_msg(sb, KERN_WARNING, + "Ignoring deprecated bh option"); break; case Opt_i_version: set_opt(sbi->s_mount_opt, I_VERSION); @@ -2912,18 +2912,7 @@ no_journal: ext4_msg(sb, KERN_ERR, "insufficient memory"); goto failed_mount_wq; } - if (test_opt(sb, NOBH)) { - if (!(test_opt(sb, DATA_FLAGS) == EXT4_MOUNT_WRITEBACK_DATA)) { - ext4_msg(sb, KERN_WARNING, "Ignoring nobh option - " - "its supported only with writeback mode"); - clear_opt(sbi->s_mount_opt, NOBH); - } - if (test_opt(sb, DIOREAD_NOLOCK)) { - ext4_msg(sb, KERN_WARNING, "dioread_nolock option is " - "not supported with nobh mode"); - goto failed_mount_wq; - } - } + EXT4_SB(sb)->dio_unwritten_wq = create_workqueue("ext4-dio-unwritten"); if (!EXT4_SB(sb)->dio_unwritten_wq) { printk(KERN_ERR "EXT4-fs: failed to create DIO workqueue\n"); -- To unsubscribe from this list: send the line "unsubscribe linux-ext4" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html