From cea9e4452ebaf18dd0951e90dc84d82a5dee40b2 Mon Sep 17 00:00:00 2001 From: Chris Mason Date: Wed, 9 Apr 2008 16:28:12 -0400 Subject: [PATCH] Change btrfs_map_block to return a structure with mappings for all stripes Signed-off-by: Chris Mason --- fs/btrfs/ctree.c | 4 +- fs/btrfs/inode.c | 8 ++-- fs/btrfs/volumes.c | 135 +++++++++++++++++++++++++++++------------------------ fs/btrfs/volumes.h | 25 ++++++++-- 4 files changed, 103 insertions(+), 69 deletions(-) diff --git a/fs/btrfs/ctree.c b/fs/btrfs/ctree.c index 3c7891c..c92c6b0 100644 --- a/fs/btrfs/ctree.c +++ b/fs/btrfs/ctree.c @@ -2025,8 +2025,10 @@ 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/fs/btrfs/inode.c b/fs/btrfs/inode.c index a8ae68c..7ae677d 100644 --- a/fs/btrfs/inode.c +++ b/fs/btrfs/inode.c @@ -301,12 +301,9 @@ int btrfs_merge_bio_hook(struct page *page, unsigned long offset, { struct btrfs_root *root = BTRFS_I(page->mapping->host)->root; struct btrfs_mapping_tree *map_tree; - struct btrfs_device *dev; u64 logical = bio->bi_sector << 9; - u64 physical; u64 length = 0; u64 map_length; - int total_devs; struct bio_vec *bvec; int i; int ret; @@ -316,8 +313,9 @@ int btrfs_merge_bio_hook(struct page *page, unsigned long offset, } map_tree = &root->fs_info->mapping_tree; map_length = length; - ret = btrfs_map_block(map_tree, READ, 0, logical, &physical, - &map_length, &dev, &total_devs); + ret = btrfs_map_block(map_tree, READ, logical, + &map_length, NULL); + if (map_length < length + size) { return 1; } diff --git a/fs/btrfs/volumes.c b/fs/btrfs/volumes.c index b9294e3c..008d364 100644 --- a/fs/btrfs/volumes.c +++ b/fs/btrfs/volumes.c @@ -26,18 +26,6 @@ #include "print-tree.h" #include "volumes.h" -struct stripe { - struct btrfs_device *dev; - u64 physical; -}; - -struct multi_bio { - atomic_t stripes; - bio_end_io_t *end_io; - void *private; - int error; -}; - struct map_lookup { u64 type; int io_align; @@ -45,11 +33,11 @@ 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 DEFINE_MUTEX(uuid_mutex); static LIST_HEAD(fs_uuids); @@ -801,8 +789,8 @@ void btrfs_mapping_tree_free(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 extent_map *em; struct map_lookup *map; @@ -810,8 +798,21 @@ int btrfs_map_block(struct btrfs_mapping_tree *map_tree, int rw, 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 & (1 << BIO_RW))) { + stripes_allocated = 1; + } +again: + if (multi_ret) { + multi = kzalloc(btrfs_multi_bio_size(stripes_allocated), + GFP_NOFS); + if (!multi) + return -ENOMEM; + } spin_lock(&em_tree->lock); em = lookup_extent_mapping(em_tree, logical, *length); @@ -821,6 +822,17 @@ int btrfs_map_block(struct btrfs_mapping_tree *map_tree, int rw, map = (struct map_lookup *)em->bdev; offset = logical - em->start; + /* if our multi bio struct is too small, back off and try again */ + if (multi_ret && (rw & (1 << BIO_RW)) && + stripes_allocated < map->num_stripes && + ((map->type & BTRFS_BLOCK_GROUP_RAID1) || + (map->type & BTRFS_BLOCK_GROUP_DUP))) { + stripes_allocated = map->num_stripes; + spin_unlock(&em_tree->lock); + free_extent_map(em); + kfree(multi); + goto again; + } stripe_nr = offset; /* * stripe_nr counts the total number of stripes we have to stride @@ -834,10 +846,22 @@ 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, em->len - offset, + map->stripe_len - stripe_offset); + } else { + *length = em->len - 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 & (1 << BIO_RW)) - *total_devs = map->num_stripes; + multi->num_stripes = map->num_stripes; else { int i; u64 least = (u64)-1; @@ -852,16 +876,10 @@ int btrfs_map_block(struct btrfs_mapping_tree *map_tree, int rw, } spin_unlock(&cur->io_lock); } - *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 & (1 << BIO_RW)) + multi->num_stripes = map->num_stripes; } else { /* * after this do_div call, stripe_nr is the number of stripes @@ -871,18 +889,17 @@ int btrfs_map_block(struct btrfs_mapping_tree *map_tree, int rw, stripe_index = do_div(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, em->len - offset, - map->stripe_len - stripe_offset); - } else { - *length = em->len - 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: free_extent_map(em); spin_unlock(&em_tree->lock); return 0; @@ -895,7 +912,7 @@ static int end_bio_multi_stripe(struct bio *bio, unsigned int bytes_done, int err) #endif { - struct multi_bio *multi = bio->bi_private; + struct btrfs_multi_bio *multi = bio->bi_private; #if LINUX_VERSION_CODE <= KERNEL_VERSION(2,6,23) if (bio->bi_size) @@ -904,7 +921,7 @@ static int end_bio_multi_stripe(struct bio *bio, if (err) multi->error = err; - if (atomic_dec_and_test(&multi->stripes)) { + if (atomic_dec_and_test(&multi->stripes_pending)) { bio->bi_private = multi->private; bio->bi_end_io = multi->end_io; @@ -927,11 +944,10 @@ int btrfs_map_bio(struct btrfs_root *root, int rw, struct bio *bio) struct btrfs_device *dev; struct bio *first_bio = bio; u64 logical = bio->bi_sector << 9; - u64 physical; u64 length = 0; u64 map_length; struct bio_vec *bvec; - struct multi_bio *multi = NULL; + struct btrfs_multi_bio *multi = NULL; int i; int ret; int dev_nr = 0; @@ -943,26 +959,22 @@ int btrfs_map_bio(struct btrfs_root *root, int rw, struct bio *bio) map_tree = &root->fs_info->mapping_tree; map_length = length; + + ret = btrfs_map_block(map_tree, rw, logical, &map_length, &multi); + BUG_ON(ret); + + total_devs = multi->num_stripes; + if (map_length < length) { + printk("mapping failed logical %Lu bio len %Lu " + "len %Lu\n", logical, length, map_length); + BUG(); + } + multi->end_io = first_bio->bi_end_io; + multi->private = first_bio->bi_private; + atomic_set(&multi->stripes_pending, multi->num_stripes); + while(dev_nr < total_devs) { - ret = btrfs_map_block(map_tree, rw, dev_nr, logical, - &physical, &map_length, &dev, - &total_devs); - if (map_length < length) { - printk("mapping failed logical %Lu bio len %Lu physical %Lu " - "len %Lu\n", logical, length, physical, map_length); - BUG(); - } - BUG_ON(map_length < length); if (total_devs > 1) { - if (!multi) { - multi = kmalloc(sizeof(*multi), GFP_NOFS); - atomic_set(&multi->stripes, 1); - multi->end_io = bio->bi_end_io; - multi->private = first_bio->bi_private; - multi->error = 0; - } else { - atomic_inc(&multi->stripes); - } if (dev_nr < total_devs - 1) { bio = bio_clone(first_bio, GFP_NOFS); BUG_ON(!bio); @@ -972,7 +984,8 @@ int btrfs_map_bio(struct btrfs_root *root, int rw, struct bio *bio) bio->bi_private = multi; bio->bi_end_io = end_bio_multi_stripe; } - bio->bi_sector = physical >> 9; + bio->bi_sector = multi->stripes[dev_nr].physical >> 9; + dev = multi->stripes[dev_nr].dev; bio->bi_bdev = dev->bdev; spin_lock(&dev->io_lock); dev->total_ios++; @@ -980,6 +993,8 @@ int btrfs_map_bio(struct btrfs_root *root, int rw, struct bio *bio) submit_bio(rw, bio); dev_nr++; } + if (total_devs == 1) + kfree(multi); return 0; } diff --git a/fs/btrfs/volumes.h b/fs/btrfs/volumes.h index 35dec3e..10ca010 100644 --- a/fs/btrfs/volumes.h +++ b/fs/btrfs/volumes.h @@ -19,6 +19,8 @@ #ifndef __BTRFS_VOLUMES_ #define __BTRFS_VOLUMES_ +#include + struct btrfs_device { struct list_head dev_list; struct btrfs_root *dev_root; @@ -69,12 +71,29 @@ struct btrfs_fs_devices { struct list_head list; }; +struct btrfs_bio_stripe { + struct btrfs_device *dev; + u64 physical; +}; + +struct btrfs_multi_bio { + atomic_t stripes_pending; + bio_end_io_t *end_io; + void *private; + 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, -- 2.7.4