From 1b74adf90b95af77a2826dc82cf5c5f38af90e52 Mon Sep 17 00:00:00 2001 From: Chris Mason Date: Wed, 9 Apr 2008 16:28:12 -0400 Subject: Change btrfs_map_block to return a structure with mappings for all stripes --- ctree.c | 4 +++- disk-io.c | 45 +++++++++++++++++------------------ volumes.c | 80 ++++++++++++++++++++++++++++++++++++++++++--------------------- volumes.h | 20 +++++++++++++--- 4 files changed, 97 insertions(+), 52 deletions(-) diff --git a/ctree.c b/ctree.c index 051cab59..9f904620 100644 --- a/ctree.c +++ b/ctree.c @@ -1928,8 +1928,10 @@ again: root->root_key.objectid, root_gen, disk_key.objectid, 0, l->start, 0); - if (IS_ERR(right)) + if (IS_ERR(right)) { + BUG_ON(1); return PTR_ERR(right); + } memset_extent_buffer(right, 0, 0, sizeof(struct btrfs_header)); btrfs_set_header_bytenr(right, right->start); diff --git a/disk-io.c b/disk-io.c index ccc2f35d..d49f2cea 100644 --- a/disk-io.c +++ b/disk-io.c @@ -97,11 +97,10 @@ struct extent_buffer *btrfs_find_create_tree_block(struct btrfs_root *root, int readahead_tree_block(struct btrfs_root *root, u64 bytenr, u32 blocksize) { int ret; - int total_devs = 1; int dev_nr; struct extent_buffer *eb; - u64 physical; u64 length; + struct btrfs_multi_bio *multi = NULL; struct btrfs_device *device; eb = btrfs_find_tree_block(root, bytenr, blocksize); @@ -111,13 +110,15 @@ int readahead_tree_block(struct btrfs_root *root, u64 bytenr, u32 blocksize) } dev_nr = 0; - ret = btrfs_map_block(&root->fs_info->mapping_tree, READ, dev_nr, - bytenr, &physical, &length, &device, - &total_devs); + length = blocksize; + ret = btrfs_map_block(&root->fs_info->mapping_tree, READ, + bytenr, &length, &multi); BUG_ON(ret); + device = multi->stripes[0].dev; device->total_ios++; blocksize = min(blocksize, (u32)(64 * 1024)); - readahead(device->fd, physical, blocksize); + readahead(device->fd, multi->stripes[0].physical, blocksize); + kfree(multi); return 0; } @@ -125,11 +126,10 @@ struct extent_buffer *read_tree_block(struct btrfs_root *root, u64 bytenr, u32 blocksize) { int ret; - int total_devs = 1; int dev_nr; struct extent_buffer *eb; - u64 physical; u64 length; + struct btrfs_multi_bio *multi = NULL; struct btrfs_device *device; eb = btrfs_find_create_tree_block(root, bytenr, blocksize); @@ -140,19 +140,21 @@ struct extent_buffer *read_tree_block(struct btrfs_root *root, u64 bytenr, return eb; dev_nr = 0; - ret = btrfs_map_block(&root->fs_info->mapping_tree, READ, dev_nr, - eb->start, &physical, &length, &device, - &total_devs); + length = blocksize; + ret = btrfs_map_block(&root->fs_info->mapping_tree, READ, + eb->start, &length, &multi); BUG_ON(ret); + device = multi->stripes[0].dev; eb->fd = device->fd; device->total_ios++; - eb->dev_bytenr = physical; + eb->dev_bytenr = multi->stripes[0].physical; ret = read_extent_from_disk(eb); if (ret) { free_extent_buffer(eb); return NULL; } btrfs_set_buffer_uptodate(eb); + kfree(multi); return eb; } @@ -160,11 +162,9 @@ int write_tree_block(struct btrfs_trans_handle *trans, struct btrfs_root *root, struct extent_buffer *eb) { int ret; - int total_devs = 1; int dev_nr; - u64 physical; u64 length; - struct btrfs_device *device; + struct btrfs_multi_bio *multi = NULL; if (check_tree_block(root, eb)) BUG(); @@ -175,18 +175,19 @@ int write_tree_block(struct btrfs_trans_handle *trans, struct btrfs_root *root, csum_tree_block(root, eb, 0); dev_nr = 0; - while(dev_nr < total_devs) { - ret = btrfs_map_block(&root->fs_info->mapping_tree, WRITE, - dev_nr, eb->start, &physical, &length, - &device, &total_devs); + length = eb->len; + ret = btrfs_map_block(&root->fs_info->mapping_tree, WRITE, + eb->start, &length, &multi); + while(dev_nr < multi->num_stripes) { BUG_ON(ret); - eb->fd = device->fd; - eb->dev_bytenr = physical; + eb->fd = multi->stripes[dev_nr].dev->fd; + eb->dev_bytenr = multi->stripes[dev_nr].physical; + multi->stripes[dev_nr].dev->total_ios++; dev_nr++; - device->total_ios++; ret = write_extent_to_disk(eb); BUG_ON(ret); } + kfree(multi); return 0; } diff --git a/volumes.c b/volumes.c index c86202de..ef2f59ca 100644 --- a/volumes.c +++ b/volumes.c @@ -43,11 +43,11 @@ struct map_lookup { int stripe_len; int sector_size; int num_stripes; - struct stripe stripes[]; + struct btrfs_bio_stripe stripes[]; }; #define map_lookup_size(n) (sizeof(struct map_lookup) + \ - (sizeof(struct stripe) * (n))) + (sizeof(struct btrfs_bio_stripe) * (n))) static LIST_HEAD(fs_uuids); @@ -733,15 +733,29 @@ void btrfs_mapping_init(struct btrfs_mapping_tree *tree) } int btrfs_map_block(struct btrfs_mapping_tree *map_tree, int rw, - int dev_nr, u64 logical, u64 *phys, u64 *length, - struct btrfs_device **dev, int *total_devs) + u64 logical, u64 *length, + struct btrfs_multi_bio **multi_ret) { struct cache_extent *ce; struct map_lookup *map; u64 offset; u64 stripe_offset; u64 stripe_nr; + int stripes_allocated = 8; int stripe_index; + int i; + struct btrfs_multi_bio *multi = NULL; + + if (multi_ret && rw == READ) { + stripes_allocated = 1; + } +again: + if (multi_ret) { + multi = kzalloc(btrfs_multi_bio_size(stripes_allocated), + GFP_NOFS); + if (!multi) + return -ENOMEM; + } ce = find_first_cache_extent(&map_tree->cache_tree, logical); BUG_ON(!ce); @@ -749,6 +763,15 @@ int btrfs_map_block(struct btrfs_mapping_tree *map_tree, int rw, map = container_of(ce, struct map_lookup, ce); offset = logical - ce->start; + /* if our multi bio struct is too small, back off and try again */ + if (multi_ret && (rw == WRITE) && + stripes_allocated < map->num_stripes && + ((map->type & BTRFS_BLOCK_GROUP_RAID1) || + (map->type & BTRFS_BLOCK_GROUP_DUP))) { + stripes_allocated = map->num_stripes; + kfree(multi); + goto again; + } stripe_nr = offset; /* * stripe_nr counts the total number of stripes we have to stride @@ -762,22 +785,28 @@ int btrfs_map_block(struct btrfs_mapping_tree *map_tree, int rw, /* stripe_offset is the offset of this block in its stripe*/ stripe_offset = offset - stripe_offset; + if (map->type & (BTRFS_BLOCK_GROUP_RAID0 | BTRFS_BLOCK_GROUP_RAID1 | + BTRFS_BLOCK_GROUP_DUP)) { + /* we limit the length of each bio to what fits in a stripe */ + *length = min_t(u64, ce->size - offset, + map->stripe_len - stripe_offset); + } else { + *length = ce->size - offset; + } + + if (!multi_ret) + goto out; + + multi->num_stripes = 1; + stripe_index = 0; if (map->type & BTRFS_BLOCK_GROUP_RAID1) { - stripe_index = dev_nr; if (rw == WRITE) - *total_devs = map->num_stripes; - else { + multi->num_stripes = map->num_stripes; + else stripe_index = stripe_nr % map->num_stripes; - *total_devs = 1; - } } else if (map->type & BTRFS_BLOCK_GROUP_DUP) { - if (rw == WRITE) { - *total_devs = map->num_stripes; - stripe_index = dev_nr; - } else { - stripe_index = 0; - *total_devs = 1; - } + if (rw == WRITE) + multi->num_stripes = map->num_stripes; } else { /* * after this do_div call, stripe_nr is the number of stripes @@ -788,18 +817,17 @@ int btrfs_map_block(struct btrfs_mapping_tree *map_tree, int rw, stripe_nr = stripe_nr / map->num_stripes; } BUG_ON(stripe_index >= map->num_stripes); - *phys = map->stripes[stripe_index].physical + stripe_offset + - stripe_nr * map->stripe_len; - if (map->type & (BTRFS_BLOCK_GROUP_RAID0 | BTRFS_BLOCK_GROUP_RAID1 | - BTRFS_BLOCK_GROUP_DUP)) { - /* we limit the length of each bio to what fits in a stripe */ - *length = min_t(u64, ce->size - offset, - map->stripe_len - stripe_offset); - } else { - *length = ce->size - offset; + BUG_ON(stripe_index != 0 && multi->num_stripes > 1); + 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; + stripe_index++; } - *dev = map->stripes[stripe_index].dev; + *multi_ret = multi; +out: return 0; } diff --git a/volumes.h b/volumes.h index a51cfe54..9928c1f9 100644 --- a/volumes.h +++ b/volumes.h @@ -66,12 +66,26 @@ struct btrfs_fs_devices { struct list_head list; }; +struct btrfs_bio_stripe { + struct btrfs_device *dev; + u64 physical; +}; + +struct btrfs_multi_bio { + int error; + int num_stripes; + struct btrfs_bio_stripe stripes[]; +}; + +#define btrfs_multi_bio_size(n) (sizeof(struct btrfs_multi_bio) + \ + (sizeof(struct btrfs_bio_stripe) * (n))) + int btrfs_alloc_dev_extent(struct btrfs_trans_handle *trans, struct btrfs_device *device, u64 owner, u64 num_bytes, u64 *start); -int btrfs_map_block(struct btrfs_mapping_tree *map_tree, int rw, int stripe_nr, - u64 logical, u64 *phys, u64 *length, - struct btrfs_device **dev, int *total_stripes); +int btrfs_map_block(struct btrfs_mapping_tree *map_tree, int rw, + u64 logical, u64 *length, + struct btrfs_multi_bio **multi_ret); int btrfs_read_sys_array(struct btrfs_root *root); int btrfs_read_chunk_tree(struct btrfs_root *root); int btrfs_alloc_chunk(struct btrfs_trans_handle *trans, -- cgit v1.2.3