diff options
Diffstat (limited to 'fs/btrfs/raid56.c')
| -rw-r--r-- | fs/btrfs/raid56.c | 60 |
1 files changed, 56 insertions, 4 deletions
diff --git a/fs/btrfs/raid56.c b/fs/btrfs/raid56.c index 1bc985821ecd..78d032323f31 100644 --- a/fs/btrfs/raid56.c +++ b/fs/btrfs/raid56.c @@ -52,6 +52,16 @@ struct btrfs_stripe_hash_table { struct btrfs_stripe_hash table[]; }; +/* + * A bvec like structure to present a sector inside a page. + * + * Unlike bvec we don't need bvlen, as it's fixed to sectorsize. + */ +struct sector_ptr { + struct page *page; + unsigned int pgoff; +}; + enum btrfs_rbio_ops { BTRFS_RBIO_WRITE, BTRFS_RBIO_READ_REBUILD, @@ -171,8 +181,12 @@ struct btrfs_raid_bio { struct page **bio_pages; /* - * bitmap to record which horizontal stripe has data + * For subpage support, we need to map each sector to above + * stripe_pages. */ + struct sector_ptr *stripe_sectors; + + /* Bitmap to record which horizontal stripe has data */ unsigned long *dbitmap; /* allocated with real_stripes-many pointers for finish_*() calls */ @@ -292,6 +306,26 @@ static int rbio_bucket(struct btrfs_raid_bio *rbio) } /* + * Update the stripe_sectors[] array to use correct page and pgoff + * + * Should be called every time any page pointer in stripes_pages[] got modified. + */ +static void index_stripe_sectors(struct btrfs_raid_bio *rbio) +{ + const u32 sectorsize = rbio->bioc->fs_info->sectorsize; + u32 offset; + int i; + + for (i = 0, offset = 0; i < rbio->nr_sectors; i++, offset += sectorsize) { + int page_index = offset >> PAGE_SHIFT; + + ASSERT(page_index < rbio->nr_pages); + rbio->stripe_sectors[i].page = rbio->stripe_pages[page_index]; + rbio->stripe_sectors[i].pgoff = offset_in_page(offset); + } +} + +/* * stealing an rbio means taking all the uptodate pages from the stripe * array in the source rbio and putting them into the destination rbio */ @@ -317,6 +351,8 @@ static void steal_rbio(struct btrfs_raid_bio *src, struct btrfs_raid_bio *dest) dest->stripe_pages[i] = s; src->stripe_pages[i] = NULL; } + index_stripe_sectors(dest); + index_stripe_sectors(src); } /* @@ -977,6 +1013,7 @@ static struct btrfs_raid_bio *alloc_rbio(struct btrfs_fs_info *fs_info, rbio = kzalloc(sizeof(*rbio) + sizeof(*rbio->stripe_pages) * num_pages + sizeof(*rbio->bio_pages) * num_pages + + sizeof(*rbio->stripe_sectors) * num_sectors + sizeof(*rbio->finish_pointers) * real_stripes + sizeof(*rbio->dbitmap) * BITS_TO_LONGS(stripe_nsectors) + sizeof(*rbio->finish_pbitmap) * BITS_TO_LONGS(stripe_nsectors), @@ -1013,6 +1050,7 @@ static struct btrfs_raid_bio *alloc_rbio(struct btrfs_fs_info *fs_info, } while (0) CONSUME_ALLOC(rbio->stripe_pages, num_pages); CONSUME_ALLOC(rbio->bio_pages, num_pages); + CONSUME_ALLOC(rbio->stripe_sectors, num_sectors); CONSUME_ALLOC(rbio->finish_pointers, real_stripes); CONSUME_ALLOC(rbio->dbitmap, BITS_TO_LONGS(stripe_nsectors)); CONSUME_ALLOC(rbio->finish_pbitmap, BITS_TO_LONGS(stripe_nsectors)); @@ -1032,16 +1070,29 @@ static struct btrfs_raid_bio *alloc_rbio(struct btrfs_fs_info *fs_info, /* allocate pages for all the stripes in the bio, including parity */ static int alloc_rbio_pages(struct btrfs_raid_bio *rbio) { - return btrfs_alloc_page_array(rbio->nr_pages, rbio->stripe_pages); + int ret; + + ret = btrfs_alloc_page_array(rbio->nr_pages, rbio->stripe_pages); + if (ret < 0) + return ret; + /* Mapping all sectors */ + index_stripe_sectors(rbio); + return 0; } /* only allocate pages for p/q stripes */ static int alloc_rbio_parity_pages(struct btrfs_raid_bio *rbio) { int data_pages = rbio_stripe_page_index(rbio, rbio->nr_data, 0); + int ret; - return btrfs_alloc_page_array(rbio->nr_pages - data_pages, - rbio->stripe_pages + data_pages); + ret = btrfs_alloc_page_array(rbio->nr_pages - data_pages, + rbio->stripe_pages + data_pages); + if (ret < 0) + return ret; + + index_stripe_sectors(rbio); + return 0; } /* @@ -2283,6 +2334,7 @@ static int alloc_rbio_essential_pages(struct btrfs_raid_bio *rbio) rbio->stripe_pages[index] = page; } } + index_stripe_sectors(rbio); return 0; } |