From: Chris Mason Date: Mon, 21 Apr 2008 14:03:05 +0000 (-0400) Subject: Btrfs: Make an unplug function that doesn't unplug every spindle X-Git-Url: http://git.lede-project.org./?a=commitdiff_plain;h=f2d8d74d7874f8f81222363cd6459a365796e35a;p=openwrt%2Fstaging%2Fblogic.git Btrfs: Make an unplug function that doesn't unplug every spindle Signed-off-by: Chris Mason --- diff --git a/fs/btrfs/disk-io.c b/fs/btrfs/disk-io.c index c829612c797e..7f5aca35494d 100644 --- a/fs/btrfs/disk-io.c +++ b/fs/btrfs/disk-io.c @@ -913,18 +913,22 @@ static int btrfs_congested_fn(void *congested_data, int bdi_bits) void btrfs_unplug_io_fn(struct backing_dev_info *bdi, struct page *page) { - struct list_head *cur; - struct btrfs_device *device; - struct btrfs_fs_info *info; + struct inode *inode = page->mapping->host; + struct extent_map_tree *em_tree; + struct extent_map *em; + u64 offset = page_offset(page); - info = (struct btrfs_fs_info *)bdi->unplug_io_data; - list_for_each(cur, &info->fs_devices->devices) { - device = list_entry(cur, struct btrfs_device, dev_list); - bdi = blk_get_backing_dev_info(device->bdev); - if (bdi->unplug_io_fn) { - bdi->unplug_io_fn(bdi, page); - } - } + em_tree = &BTRFS_I(inode)->extent_tree; + spin_lock(&em_tree->lock); + em = lookup_extent_mapping(em_tree, offset, PAGE_CACHE_SIZE); + spin_unlock(&em_tree->lock); + if (!em) + return; + + offset = offset - em->start; + btrfs_unplug_page(&BTRFS_I(inode)->root->fs_info->mapping_tree, + em->block_start + offset, page); + free_extent_map(em); } static int setup_bdi(struct btrfs_fs_info *info, struct backing_dev_info *bdi) diff --git a/fs/btrfs/inode.c b/fs/btrfs/inode.c index 5b1514e58de4..e875c7c8a647 100644 --- a/fs/btrfs/inode.c +++ b/fs/btrfs/inode.c @@ -313,13 +313,9 @@ int btrfs_merge_bio_hook(struct page *page, unsigned long offset, u64 logical = bio->bi_sector << 9; u64 length = 0; u64 map_length; - struct bio_vec *bvec; - int i; int ret; - bio_for_each_segment(bvec, bio, i) { - length += bvec->bv_len; - } + length = bio->bi_size; map_tree = &root->fs_info->mapping_tree; map_length = length; ret = btrfs_map_block(map_tree, READ, logical, diff --git a/fs/btrfs/volumes.c b/fs/btrfs/volumes.c index 4fc92cf813d8..460240706505 100644 --- a/fs/btrfs/volumes.c +++ b/fs/btrfs/volumes.c @@ -18,6 +18,7 @@ #include #include #include +#include #include #include "ctree.h" #include "extent_map.h" @@ -930,9 +931,10 @@ int btrfs_num_copies(struct btrfs_mapping_tree *map_tree, u64 logical, u64 len) return ret; } -int btrfs_map_block(struct btrfs_mapping_tree *map_tree, int rw, - u64 logical, u64 *length, - struct btrfs_multi_bio **multi_ret, int mirror_num) +static int __btrfs_map_block(struct btrfs_mapping_tree *map_tree, int rw, + u64 logical, u64 *length, + struct btrfs_multi_bio **multi_ret, + int mirror_num, struct page *unplug_page) { struct extent_map *em; struct map_lookup *map; @@ -944,6 +946,7 @@ int btrfs_map_block(struct btrfs_mapping_tree *map_tree, int rw, int stripes_required = 1; int stripe_index; int i; + int num_stripes; struct btrfs_multi_bio *multi = NULL; if (multi_ret && !(rw & (1 << BIO_RW))) { @@ -960,10 +963,14 @@ again: spin_lock(&em_tree->lock); em = lookup_extent_mapping(em_tree, logical, *length); spin_unlock(&em_tree->lock); + + if (!em && unplug_page) + return 0; + if (!em) { printk("unable to find logical %Lu\n", logical); + BUG(); } - BUG_ON(!em); BUG_ON(em->start > logical || em->start + em->len < logical); map = (struct map_lookup *)em->bdev; @@ -1010,14 +1017,15 @@ again: } else { *length = em->len - offset; } - if (!multi_ret) + + if (!multi_ret && !unplug_page) goto out; - multi->num_stripes = 1; + num_stripes = 1; stripe_index = 0; if (map->type & BTRFS_BLOCK_GROUP_RAID1) { - if (rw & (1 << BIO_RW)) - multi->num_stripes = map->num_stripes; + if (unplug_page || (rw & (1 << BIO_RW))) + num_stripes = map->num_stripes; else if (mirror_num) { stripe_index = mirror_num - 1; } else { @@ -1037,7 +1045,7 @@ again: } } else if (map->type & BTRFS_BLOCK_GROUP_DUP) { if (rw & (1 << BIO_RW)) - multi->num_stripes = map->num_stripes; + num_stripes = map->num_stripes; else if (mirror_num) stripe_index = mirror_num - 1; } else if (map->type & BTRFS_BLOCK_GROUP_RAID10) { @@ -1047,8 +1055,8 @@ again: stripe_index = do_div(stripe_nr, factor); stripe_index *= map->sub_stripes; - if (rw & (1 << BIO_RW)) - multi->num_stripes = map->sub_stripes; + if (unplug_page || (rw & (1 << BIO_RW))) + num_stripes = map->sub_stripes; else if (mirror_num) stripe_index += mirror_num - 1; else @@ -1063,19 +1071,50 @@ again: } BUG_ON(stripe_index >= map->num_stripes); - for (i = 0; i < multi->num_stripes; i++) { - multi->stripes[i].physical = - map->stripes[stripe_index].physical + stripe_offset + - stripe_nr * map->stripe_len; - multi->stripes[i].dev = map->stripes[stripe_index].dev; + for (i = 0; i < num_stripes; i++) { + if (unplug_page) { + struct btrfs_device *device; + struct backing_dev_info *bdi; + + device = map->stripes[stripe_index].dev; + bdi = blk_get_backing_dev_info(device->bdev); + if (bdi->unplug_io_fn) { + bdi->unplug_io_fn(bdi, unplug_page); + } + } else { + multi->stripes[i].physical = + map->stripes[stripe_index].physical + + stripe_offset + stripe_nr * map->stripe_len; + multi->stripes[i].dev = map->stripes[stripe_index].dev; + } stripe_index++; } - *multi_ret = multi; + if (multi_ret) { + *multi_ret = multi; + multi->num_stripes = num_stripes; + } out: free_extent_map(em); return 0; } +int btrfs_map_block(struct btrfs_mapping_tree *map_tree, int rw, + u64 logical, u64 *length, + struct btrfs_multi_bio **multi_ret, int mirror_num) +{ + return __btrfs_map_block(map_tree, rw, logical, length, multi_ret, + mirror_num, NULL); +} + +int btrfs_unplug_page(struct btrfs_mapping_tree *map_tree, + u64 logical, struct page *page) +{ + u64 length = PAGE_CACHE_SIZE; + return __btrfs_map_block(map_tree, READ, logical, &length, + NULL, 0, page); +} + + #if LINUX_VERSION_CODE > KERNEL_VERSION(2,6,23) static void end_bio_multi_stripe(struct bio *bio, int err) #else @@ -1122,16 +1161,12 @@ int btrfs_map_bio(struct btrfs_root *root, int rw, struct bio *bio, u64 logical = bio->bi_sector << 9; u64 length = 0; u64 map_length; - struct bio_vec *bvec; struct btrfs_multi_bio *multi = NULL; - int i; int ret; int dev_nr = 0; int total_devs = 1; - bio_for_each_segment(bvec, bio, i) { - length += bvec->bv_len; - } + length = bio->bi_size; map_tree = &root->fs_info->mapping_tree; map_length = length; diff --git a/fs/btrfs/volumes.h b/fs/btrfs/volumes.h index f9cae3072171..dfe7e8a9507c 100644 --- a/fs/btrfs/volumes.h +++ b/fs/btrfs/volumes.h @@ -119,4 +119,6 @@ int btrfs_add_device(struct btrfs_trans_handle *trans, struct btrfs_device *device); int btrfs_cleanup_fs_uuids(void); int btrfs_num_copies(struct btrfs_mapping_tree *map_tree, u64 logical, u64 len); +int btrfs_unplug_page(struct btrfs_mapping_tree *map_tree, + u64 logical, struct page *page); #endif