From 8fb0e342481c4d80040670fec915f0b9c7c6499a Mon Sep 17 00:00:00 2001 From: "Aneesh Kumar K.V" Date: Tue, 12 May 2009 16:22:37 -0400 Subject: vfs: Add BUG_ON for delayed and unwritten flags in submit_bh() The BH_Delay and BH_Unwritten flags should never leak out to submit_bh(). So add some BUG_ON() checks to submit_bh so we can get a stack trace and determine how and why this might have happened. (Note that only XFS and ext4 use these buffer head flags, and XFS does not use submit_bh(). So this patch should only modify behavior for ext4.) Signed-off-by: Aneesh Kumar K.V Signed-off-by: "Theodore Ts'o" Cc: linux-fsdevel@vger.kernel.org --- fs/buffer.c | 2 ++ 1 file changed, 2 insertions(+) (limited to 'fs/buffer.c') diff --git a/fs/buffer.c b/fs/buffer.c index aed297739eb..ad011290022 100644 --- a/fs/buffer.c +++ b/fs/buffer.c @@ -2933,6 +2933,8 @@ int submit_bh(int rw, struct buffer_head * bh) BUG_ON(!buffer_locked(bh)); BUG_ON(!buffer_mapped(bh)); BUG_ON(!bh->b_end_io); + BUG_ON(buffer_delay(bh)); + BUG_ON(buffer_unwritten(bh)); /* * Mask in barrier bit for a write (could be either a WRITE or a -- cgit v1.2.3 From e1defc4ff0cf57aca6c5e3ff99fa503f5943c1f1 Mon Sep 17 00:00:00 2001 From: "Martin K. Petersen" Date: Fri, 22 May 2009 17:17:49 -0400 Subject: block: Do away with the notion of hardsect_size Until now we have had a 1:1 mapping between storage device physical block size and the logical block sized used when addressing the device. With SATA 4KB drives coming out that will no longer be the case. The sector size will be 4KB but the logical block size will remain 512-bytes. Hence we need to distinguish between the physical block size and the logical ditto. This patch renames hardsect_size to logical_block_size. Signed-off-by: Martin K. Petersen Signed-off-by: Jens Axboe --- fs/buffer.c | 6 +++--- 1 file changed, 3 insertions(+), 3 deletions(-) (limited to 'fs/buffer.c') diff --git a/fs/buffer.c b/fs/buffer.c index aed297739eb..36e2bbc60ec 100644 --- a/fs/buffer.c +++ b/fs/buffer.c @@ -1085,12 +1085,12 @@ static struct buffer_head * __getblk_slow(struct block_device *bdev, sector_t block, int size) { /* Size must be multiple of hard sectorsize */ - if (unlikely(size & (bdev_hardsect_size(bdev)-1) || + if (unlikely(size & (bdev_logical_block_size(bdev)-1) || (size < 512 || size > PAGE_SIZE))) { printk(KERN_ERR "getblk(): invalid block size %d requested\n", size); - printk(KERN_ERR "hardsect size: %d\n", - bdev_hardsect_size(bdev)); + printk(KERN_ERR "logical block size: %d\n", + bdev_logical_block_size(bdev)); dump_stack(); return NULL; -- cgit v1.2.3 From 460bcf57b128ce1c0dd553d905fedc097f9955c6 Mon Sep 17 00:00:00 2001 From: Theodore Ts'o Date: Tue, 12 May 2009 07:37:56 -0400 Subject: Fix nobh_truncate_page() to not pass stack garbage to get_block() The nobh_truncate_page() function is used by ext2, exofs, and jfs. Of these three, only ext2 and jfs's get_block() function pays attention to bh->b_size --- which is normally always the filesystem blocksize except when the get_block() function is called by either mpage_readpage(), mpage_readpages(), or the direct I/O routines in fs/direct_io.c. Unfortunately, nobh_truncate_page() does not initialize map_bh before calling the filesystem-supplied get_block() function. So ext2 and jfs will try to calculate the number of blocks to map by taking stack garbage and shifting it left by inode->i_blkbits. This should be *mostly* harmless (except the filesystem will do some unnneeded work) unless the stack garbage is less than filesystem's blocksize, in which case maxblocks will be zero, and the attempt to find out whether or not the filesystem has a hole at a given logical block will fail, and the page cache entry might not get zero'ed out. Also if the stack garbage in in map_bh->state happens to have the BH_Mapped bit set, there could be an attempt to call readpage() on a non-existent page, which could cause nobh_truncate_page() to return an error when it should not. Fix this by initializing map_bh->state and map_bh->size. Fortunately, it's probably fairly unlikely that ext2 and jfs users mount with nobh these days. Signed-off-by: "Theodore Ts'o" Cc: Dave Kleikamp Cc: linux-fsdevel@vger.kernel.org Signed-off-by: Al Viro --- fs/buffer.c | 2 ++ 1 file changed, 2 insertions(+) (limited to 'fs/buffer.c') diff --git a/fs/buffer.c b/fs/buffer.c index aed297739eb..49106127a4a 100644 --- a/fs/buffer.c +++ b/fs/buffer.c @@ -2736,6 +2736,8 @@ has_buffers: pos += blocksize; } + map_bh.b_size = blocksize; + map_bh.b_state = 0; err = get_block(inode, iblock, &map_bh, 0); if (err) goto unlock; -- cgit v1.2.3