From 875b2376fd663832bf45f7285c9d26cb8c52929a Mon Sep 17 00:00:00 2001 From: Randy Dunlap Date: Mon, 28 Dec 2020 19:47:06 -0800 Subject: fs: block_dev.c: fix kernel-doc warnings from struct block_device changes Fix new kernel-doc warnings in fs/block_dev.c: ../fs/block_dev.c:1066: warning: Excess function parameter 'whole' description in 'bd_abort_claiming' ../fs/block_dev.c:1837: warning: Function parameter or member 'dev' not described in 'lookup_bdev' Fixes: 4e7b5671c6a8 ("block: remove i_bdev") Fixes: 37c3fc9abb25 ("block: simplify the block device claiming interface") Signed-off-by: Randy Dunlap Cc: Jens Axboe Cc: Christoph Hellwig Cc: linux-fsdevel@vger.kernel.org Cc: Alexander Viro Signed-off-by: Jens Axboe --- fs/block_dev.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) (limited to 'fs/block_dev.c') diff --git a/fs/block_dev.c b/fs/block_dev.c index 9293045e128c..3e5b02f6606c 100644 --- a/fs/block_dev.c +++ b/fs/block_dev.c @@ -1055,7 +1055,6 @@ static void bd_finish_claiming(struct block_device *bdev, void *holder) /** * bd_abort_claiming - abort claiming of a block device * @bdev: block device of interest - * @whole: whole block device * @holder: holder that has claimed @bdev * * Abort claiming of a block device when the exclusive open failed. This can be @@ -1828,6 +1827,7 @@ const struct file_operations def_blk_fops = { /** * lookup_bdev - lookup a struct block_device by name * @pathname: special file representing the block device + * @dev: return value of the block device's dev_t * * Get a reference to the blockdevice at @pathname in the current * namespace if possible and return it. Return ERR_PTR(error) -- cgit v1.3-8-gc7d7 From 04a6a536bc3fd1436fc78c546c6b3ecdccbfaf6d Mon Sep 17 00:00:00 2001 From: Satya Tangirala Date: Thu, 24 Dec 2020 04:49:54 +0000 Subject: fs: Fix freeze_bdev()/thaw_bdev() accounting of bd_fsfreeze_sb freeze/thaw_bdev() currently use bdev->bd_fsfreeze_count to infer whether or not bdev->bd_fsfreeze_sb is valid (it's valid iff bd_fsfreeze_count is non-zero). thaw_bdev() doesn't nullify bd_fsfreeze_sb. But this means a freeze_bdev() call followed by a thaw_bdev() call can leave bd_fsfreeze_sb with a non-null value, while bd_fsfreeze_count is zero. If freeze_bdev() is called again, and this time get_active_super() returns NULL (e.g. because the FS is unmounted), we'll end up with bd_fsfreeze_count > 0, but bd_fsfreeze_sb is *untouched* - it stays the same (now garbage) value. A subsequent thaw_bdev() will decide that the bd_fsfreeze_sb value is legitimate (since bd_fsfreeze_count > 0), and attempt to use it. Fix this by always setting bd_fsfreeze_sb to NULL when bd_fsfreeze_count is successfully decremented to 0 in thaw_sb(). Alternatively, we could set bd_fsfreeze_sb to whatever get_active_super() returns in freeze_bdev() whenever bd_fsfreeze_count is successfully incremented to 1 from 0 (which can be achieved cleanly by moving the line currently setting bd_fsfreeze_sb to immediately after the "sync:" label, but it might be a little too subtle/easily overlooked in future). This fixes the currently panicking xfstests generic/085. Fixes: 040f04bd2e82 ("fs: simplify freeze_bdev/thaw_bdev") Signed-off-by: Satya Tangirala Reviewed-by: Christoph Hellwig Reviewed-by: Darrick J. Wong Signed-off-by: Jens Axboe --- fs/block_dev.c | 2 ++ 1 file changed, 2 insertions(+) (limited to 'fs/block_dev.c') diff --git a/fs/block_dev.c b/fs/block_dev.c index 3e5b02f6606c..e454c5a81043 100644 --- a/fs/block_dev.c +++ b/fs/block_dev.c @@ -605,6 +605,8 @@ int thaw_bdev(struct block_device *bdev) error = thaw_super(sb); if (error) bdev->bd_fsfreeze_count++; + else + bdev->bd_fsfreeze_sb = NULL; out: mutex_unlock(&bdev->bd_fsfreeze_mutex); return error; -- cgit v1.3-8-gc7d7 From 2d2f6f1b4799428d160c021dd652bc3e3593945e Mon Sep 17 00:00:00 2001 From: Christoph Hellwig Date: Thu, 7 Jan 2021 19:36:40 +0100 Subject: block: pre-initialize struct block_device in bdev_alloc_inode bdev_evict_inode and bdev_free_inode are also called for the root inode of bdevfs, for which bdev_alloc is never called. Move the zeroing o f struct block_device and the initialization of the bd_bdi field into bdev_alloc_inode to make sure they are initialized for the root inode as well. Fixes: e6cb53827ed6 ("block: initialize struct block_device in bdev_alloc") Reported-by: Alexey Kardashevskiy Tested-by: Alexey Kardashevskiy Signed-off-by: Christoph Hellwig Signed-off-by: Jens Axboe --- fs/block_dev.c | 5 +++-- 1 file changed, 3 insertions(+), 2 deletions(-) (limited to 'fs/block_dev.c') diff --git a/fs/block_dev.c b/fs/block_dev.c index e454c5a81043..3b8963e228a1 100644 --- a/fs/block_dev.c +++ b/fs/block_dev.c @@ -776,8 +776,11 @@ static struct kmem_cache * bdev_cachep __read_mostly; static struct inode *bdev_alloc_inode(struct super_block *sb) { struct bdev_inode *ei = kmem_cache_alloc(bdev_cachep, GFP_KERNEL); + if (!ei) return NULL; + memset(&ei->bdev, 0, sizeof(ei->bdev)); + ei->bdev.bd_bdi = &noop_backing_dev_info; return &ei->vfs_inode; } @@ -871,14 +874,12 @@ struct block_device *bdev_alloc(struct gendisk *disk, u8 partno) mapping_set_gfp_mask(&inode->i_data, GFP_USER); bdev = I_BDEV(inode); - memset(bdev, 0, sizeof(*bdev)); mutex_init(&bdev->bd_mutex); mutex_init(&bdev->bd_fsfreeze_mutex); spin_lock_init(&bdev->bd_size_lock); bdev->bd_disk = disk; bdev->bd_partno = partno; bdev->bd_inode = inode; - bdev->bd_bdi = &noop_backing_dev_info; #ifdef CONFIG_SYSFS INIT_LIST_HEAD(&bdev->bd_holder_disks); #endif -- cgit v1.3-8-gc7d7 From 8dc932d3e8afb65e12eba7495f046c83884c49bf Mon Sep 17 00:00:00 2001 From: Maxim Mikityanskiy Date: Tue, 26 Jan 2021 21:59:07 +0200 Subject: Revert "block: simplify set_init_blocksize" to regain lost performance The cited commit introduced a serious regression with SATA write speed, as found by bisecting. This patch reverts this commit, which restores write speed back to the values observed before this commit. The performance tests were done on a Helios4 NAS (2nd batch) with 4 HDDs (WD8003FFBX) using dd (bs=1M count=2000). "Direct" is a test with a single HDD, the rest are different RAID levels built over the first partitions of 4 HDDs. Test results are in MB/s, R is read, W is write. | Direct | RAID0 | RAID10 f2 | RAID10 n2 | RAID6 ----------------+--------+-------+-----------+-----------+-------- 9011495c9466 | R:256 | R:313 | R:276 | R:313 | R:323 (before faulty) | W:254 | W:253 | W:195 | W:204 | W:117 ----------------+--------+-------+-----------+-----------+-------- 5ff9f19231a0 | R:257 | R:398 | R:312 | R:344 | R:391 (faulty commit) | W:154 | W:122 | W:67.7 | W:66.6 | W:67.2 ----------------+--------+-------+-----------+-----------+-------- 5.10.10 | R:256 | R:401 | R:312 | R:356 | R:375 unpatched | W:149 | W:123 | W:64 | W:64.1 | W:61.5 ----------------+--------+-------+-----------+-----------+-------- 5.10.10 | R:255 | R:396 | R:312 | R:340 | R:393 patched | W:247 | W:274 | W:220 | W:225 | W:121 Applying this patch doesn't hurt read performance, while improves the write speed by 1.5x - 3.5x (more impact on RAID tests). The write speed is restored back to the state before the faulty commit, and even a bit higher in RAID tests (which aren't HDD-bound on this device) - that is likely related to other optimizations done between the faulty commit and 5.10.10 which also improved the read speed. Signed-off-by: Maxim Mikityanskiy Fixes: 5ff9f19231a0 ("block: simplify set_init_blocksize") Cc: Christoph Hellwig Cc: Jens Axboe Acked-by: Christoph Hellwig Signed-off-by: Jens Axboe --- fs/block_dev.c | 10 +++++++++- 1 file changed, 9 insertions(+), 1 deletion(-) (limited to 'fs/block_dev.c') diff --git a/fs/block_dev.c b/fs/block_dev.c index 3b8963e228a1..235b5042672e 100644 --- a/fs/block_dev.c +++ b/fs/block_dev.c @@ -130,7 +130,15 @@ EXPORT_SYMBOL(truncate_bdev_range); static void set_init_blocksize(struct block_device *bdev) { - bdev->bd_inode->i_blkbits = blksize_bits(bdev_logical_block_size(bdev)); + unsigned int bsize = bdev_logical_block_size(bdev); + loff_t size = i_size_read(bdev->bd_inode); + + while (bsize < PAGE_SIZE) { + if (size & bsize) + break; + bsize <<= 1; + } + bdev->bd_inode->i_blkbits = blksize_bits(bsize); } int set_blocksize(struct block_device *bdev, int size) -- cgit v1.3-8-gc7d7