From 309dca309fc39a9e3c31b916393b74bd174fd74e Mon Sep 17 00:00:00 2001 From: Christoph Hellwig Date: Sun, 24 Jan 2021 11:02:34 +0100 Subject: block: store a block_device pointer in struct bio Replace the gendisk pointer in struct bio with a pointer to the newly improved struct block device. From that the gendisk can be trivially accessed with an extra indirection, but it also allows to directly look up all information related to partition remapping. Signed-off-by: Christoph Hellwig Acked-by: Tejun Heo Signed-off-by: Jens Axboe --- fs/btrfs/raid56.c | 7 ++----- 1 file changed, 2 insertions(+), 5 deletions(-) (limited to 'fs/btrfs/raid56.c') diff --git a/fs/btrfs/raid56.c b/fs/btrfs/raid56.c index 93fbf87bdc8d..b2204a2942cb 100644 --- a/fs/btrfs/raid56.c +++ b/fs/btrfs/raid56.c @@ -1105,8 +1105,7 @@ static int rbio_add_io_page(struct btrfs_raid_bio *rbio, * devices or if they are not contiguous */ if (last_end == disk_start && !last->bi_status && - last->bi_disk == stripe->dev->bdev->bd_disk && - last->bi_partno == stripe->dev->bdev->bd_partno) { + last->bi_bdev == stripe->dev->bdev) { ret = bio_add_page(last, page, PAGE_SIZE, 0); if (ret == PAGE_SIZE) return 0; @@ -1357,9 +1356,7 @@ static int find_bio_stripe(struct btrfs_raid_bio *rbio, for (i = 0; i < rbio->bbio->num_stripes; i++) { stripe = &rbio->bbio->stripes[i]; if (in_range(physical, stripe->physical, rbio->stripe_len) && - stripe->dev->bdev && - bio->bi_disk == stripe->dev->bdev->bd_disk && - bio->bi_partno == stripe->dev->bdev->bd_partno) { + stripe->dev->bdev && bio->bi_bdev == stripe->dev->bdev) { return i; } } -- cgit v1.2.3 From fe3b7bb085a0b1fb26d622a5eccc7dbb5c4f82fb Mon Sep 17 00:00:00 2001 From: Yang Li Date: Thu, 21 Jan 2021 16:19:47 +0800 Subject: btrfs: remove redundant NULL check before kvfree Fix below warnings reported by coccicheck: ./fs/btrfs/raid56.c:237:2-8: WARNING: NULL check before some freeing functions is not needed. Reported-by: Abaci Robot Reviewed-by: Anand Jain Signed-off-by: Yang Li Reviewed-by: David Sterba Signed-off-by: David Sterba --- fs/btrfs/raid56.c | 3 +-- 1 file changed, 1 insertion(+), 2 deletions(-) (limited to 'fs/btrfs/raid56.c') diff --git a/fs/btrfs/raid56.c b/fs/btrfs/raid56.c index 93fbf87bdc8d..5394641541f7 100644 --- a/fs/btrfs/raid56.c +++ b/fs/btrfs/raid56.c @@ -233,8 +233,7 @@ int btrfs_alloc_stripe_hash_table(struct btrfs_fs_info *info) } x = cmpxchg(&info->stripe_hash_table, NULL, table); - if (x) - kvfree(x); + kvfree(x); return 0; } -- cgit v1.2.3 From d70cef0d46729808dc53f145372c02b145c92604 Mon Sep 17 00:00:00 2001 From: Ira Weiny Date: Wed, 27 Jan 2021 22:15:03 -0800 Subject: btrfs: fix raid6 qstripe kmap When a qstripe is required an extra page is allocated and mapped. There were 3 problems: 1) There is no corresponding call of kunmap() for the qstripe page. 2) There is no reason to map the qstripe page more than once if the number of bits set in rbio->dbitmap is greater than one. 3) There is no reason to map the parity page and unmap it each time through the loop. The page memory can continue to be reused with a single mapping on each iteration by raid6_call.gen_syndrome() without remapping. So map the page for the duration of the loop. Similarly, improve the algorithm by mapping the parity page just 1 time. Fixes: 5a6ac9eacb49 ("Btrfs, raid56: support parity scrub on raid56") CC: stable@vger.kernel.org # 4.4.x: c17af96554a8: btrfs: raid56: simplify tracking of Q stripe presence CC: stable@vger.kernel.org # 4.4.x Signed-off-by: Ira Weiny Reviewed-by: David Sterba Signed-off-by: David Sterba --- fs/btrfs/raid56.c | 21 ++++++++++----------- 1 file changed, 10 insertions(+), 11 deletions(-) (limited to 'fs/btrfs/raid56.c') diff --git a/fs/btrfs/raid56.c b/fs/btrfs/raid56.c index 5394641541f7..abf17fae0912 100644 --- a/fs/btrfs/raid56.c +++ b/fs/btrfs/raid56.c @@ -2362,16 +2362,21 @@ static noinline void finish_parity_scrub(struct btrfs_raid_bio *rbio, SetPageUptodate(p_page); if (has_qstripe) { + /* RAID6, allocate and map temp space for the Q stripe */ q_page = alloc_page(GFP_NOFS | __GFP_HIGHMEM); if (!q_page) { __free_page(p_page); goto cleanup; } SetPageUptodate(q_page); + pointers[rbio->real_stripes - 1] = kmap(q_page); } atomic_set(&rbio->error, 0); + /* Map the parity stripe just once */ + pointers[nr_data] = kmap(p_page); + for_each_set_bit(pagenr, rbio->dbitmap, rbio->stripe_npages) { struct page *p; void *parity; @@ -2381,16 +2386,8 @@ static noinline void finish_parity_scrub(struct btrfs_raid_bio *rbio, pointers[stripe] = kmap(p); } - /* then add the parity stripe */ - pointers[stripe++] = kmap(p_page); - if (has_qstripe) { - /* - * raid6, add the qstripe and call the - * library function to fill in our p/q - */ - pointers[stripe++] = kmap(q_page); - + /* RAID6, call the library function to fill in our P/Q */ raid6_call.gen_syndrome(rbio->real_stripes, PAGE_SIZE, pointers); } else { @@ -2411,12 +2408,14 @@ static noinline void finish_parity_scrub(struct btrfs_raid_bio *rbio, for (stripe = 0; stripe < nr_data; stripe++) kunmap(page_in_rbio(rbio, stripe, pagenr, 0)); - kunmap(p_page); } + kunmap(p_page); __free_page(p_page); - if (q_page) + if (q_page) { + kunmap(q_page); __free_page(q_page); + } writeback: /* -- cgit v1.2.3 From 80cc83842394e5ad3e93487359106aab3420bcb7 Mon Sep 17 00:00:00 2001 From: Ira Weiny Date: Tue, 9 Feb 2021 22:22:20 -0800 Subject: btrfs: use copy_highpage() instead of 2 kmaps() There are many places where kmap/memove/kunmap patterns occur. This pattern exists in the core common function copy_highpage(). Use copy_highpage to avoid open coding the use of kmap and leverages the core functions use of kmap_local_page(). Development of this patch was aided by the following coccinelle script: // // SPDX-License-Identifier: GPL-2.0-only // Find kmap/copypage/kunmap pattern and replace with copy_highpage calls // // NOTE: The expressions in the copy page version of this kmap pattern are // overly complex and so these all need individual attention. // // Confidence: Low // Copyright: (C) 2021 Intel Corporation // URL: http://coccinelle.lip6.fr/ // Comments: // Options: // // Then a copy_page where we have 2 pages involved. // @ copy_page_rule @ expression page, page2, To, From, Size; identifier ptr, ptr2; type VP, VP2; @@ /* kmap */ ( -VP ptr = kmap(page); ... -VP2 ptr2 = kmap(page2); | -VP ptr = kmap_atomic(page); ... -VP2 ptr2 = kmap_atomic(page2); | -ptr = kmap(page); ... -ptr2 = kmap(page2); | -ptr = kmap_atomic(page); ... -ptr2 = kmap_atomic(page2); ) // 1 or more copy versions of the entire page <+... ( -copy_page(To, From); +copy_highpage(To, From); | -memmove(To, From, Size); +memmoveExtra(To, From, Size); ) ...+> /* kunmap */ ( -kunmap(page2); ... -kunmap(page); | -kunmap(page); ... -kunmap(page2); | -kmap_atomic(ptr2); ... -kmap_atomic(ptr); ) // Remove any pointers left unused @ depends on copy_page_rule @ identifier copy_page_rule.ptr; identifier copy_page_rule.ptr2; type VP, VP1; type VP2, VP21; @@ -VP ptr; ... when != ptr; ? VP1 ptr; -VP2 ptr2; ... when != ptr2; ? VP21 ptr2; // Reviewed-by: Christoph Hellwig Signed-off-by: Ira Weiny Reviewed-by: David Sterba Signed-off-by: David Sterba --- fs/btrfs/raid56.c | 10 +--------- 1 file changed, 1 insertion(+), 9 deletions(-) (limited to 'fs/btrfs/raid56.c') diff --git a/fs/btrfs/raid56.c b/fs/btrfs/raid56.c index 93fbf87bdc8d..c86aff9c7daa 100644 --- a/fs/btrfs/raid56.c +++ b/fs/btrfs/raid56.c @@ -250,8 +250,6 @@ int btrfs_alloc_stripe_hash_table(struct btrfs_fs_info *info) static void cache_rbio_pages(struct btrfs_raid_bio *rbio) { int i; - char *s; - char *d; int ret; ret = alloc_rbio_pages(rbio); @@ -262,13 +260,7 @@ static void cache_rbio_pages(struct btrfs_raid_bio *rbio) if (!rbio->bio_pages[i]) continue; - s = kmap(rbio->bio_pages[i]); - d = kmap(rbio->stripe_pages[i]); - - copy_page(d, s); - - kunmap(rbio->bio_pages[i]); - kunmap(rbio->stripe_pages[i]); + copy_highpage(rbio->stripe_pages[i], rbio->bio_pages[i]); SetPageUptodate(rbio->stripe_pages[i]); } set_bit(RBIO_CACHE_READY_BIT, &rbio->flags); -- cgit v1.2.3