From 10e27980f2ff66ba0c6da55f33b4814d5bc86573 Mon Sep 17 00:00:00 2001 From: Johannes Thumshirn Date: Thu, 14 Sep 2023 09:07:00 -0700 Subject: [PATCH] btrfs: lookup physical address from stripe extent Lookup the physical address from the raid stripe tree when a read on an RAID volume formatted with the raid stripe tree was attempted. Signed-off-by: Johannes Thumshirn Signed-off-by: David Sterba --- fs/btrfs/raid-stripe-tree.c | 117 ++++++++++++++++++++++++++++++++++++ fs/btrfs/raid-stripe-tree.h | 9 +++ fs/btrfs/volumes.c | 42 ++++++++++--- 3 files changed, 158 insertions(+), 10 deletions(-) diff --git a/fs/btrfs/raid-stripe-tree.c b/fs/btrfs/raid-stripe-tree.c index f2e052dfb0a5d..c7e18a85f7233 100644 --- a/fs/btrfs/raid-stripe-tree.c +++ b/fs/btrfs/raid-stripe-tree.c @@ -142,3 +142,120 @@ int btrfs_insert_raid_extent(struct btrfs_trans_handle *trans, return ret; } + +int btrfs_get_raid_extent_offset(struct btrfs_fs_info *fs_info, + u64 logical, u64 *length, u64 map_type, + u32 stripe_index, struct btrfs_io_stripe *stripe) +{ + struct btrfs_root *stripe_root = fs_info->stripe_root; + struct btrfs_stripe_extent *stripe_extent; + struct btrfs_key stripe_key; + struct btrfs_key found_key; + struct btrfs_path *path; + struct extent_buffer *leaf; + const u64 end = logical + *length; + int num_stripes; + u8 encoding; + u64 offset; + u64 found_logical; + u64 found_length; + u64 found_end; + int slot; + int ret; + + stripe_key.objectid = logical; + stripe_key.type = BTRFS_RAID_STRIPE_KEY; + stripe_key.offset = 0; + + path = btrfs_alloc_path(); + if (!path) + return -ENOMEM; + + ret = btrfs_search_slot(NULL, stripe_root, &stripe_key, path, 0, 0); + if (ret < 0) + goto free_path; + if (ret) { + if (path->slots[0] != 0) + path->slots[0]--; + } + + while (1) { + leaf = path->nodes[0]; + slot = path->slots[0]; + + btrfs_item_key_to_cpu(leaf, &found_key, slot); + found_logical = found_key.objectid; + found_length = found_key.offset; + found_end = found_logical + found_length; + + if (found_logical > end) { + ret = -ENOENT; + goto out; + } + + if (in_range(logical, found_logical, found_length)) + break; + + ret = btrfs_next_item(stripe_root, path); + if (ret) + goto out; + } + + offset = logical - found_logical; + + /* + * If we have a logically contiguous, but physically non-continuous + * range, we need to split the bio. Record the length after which we + * must split the bio. + */ + if (end > found_end) + *length -= end - found_end; + + num_stripes = btrfs_num_raid_stripes(btrfs_item_size(leaf, slot)); + stripe_extent = btrfs_item_ptr(leaf, slot, struct btrfs_stripe_extent); + encoding = btrfs_stripe_extent_encoding(leaf, stripe_extent); + + if (encoding != btrfs_bg_flags_to_raid_index(map_type)) { + ret = -EUCLEAN; + btrfs_handle_fs_error(fs_info, ret, + "on-disk stripe encoding %d doesn't match RAID index %d", + encoding, + btrfs_bg_flags_to_raid_index(map_type)); + goto out; + } + + for (int i = 0; i < num_stripes; i++) { + struct btrfs_raid_stride *stride = &stripe_extent->strides[i]; + u64 devid = btrfs_raid_stride_devid(leaf, stride); + u64 physical = btrfs_raid_stride_physical(leaf, stride); + + if (devid != stripe->dev->devid) + continue; + + if ((map_type & BTRFS_BLOCK_GROUP_DUP) && stripe_index != i) + continue; + + stripe->physical = physical + offset; + + ret = 0; + goto free_path; + } + + /* If we're here, we haven't found the requested devid in the stripe. */ + ret = -ENOENT; +out: + if (ret > 0) + ret = -ENOENT; + if (ret && ret != -EIO) { + if (IS_ENABLED(CONFIG_BTRFS_DEBUG)) + btrfs_print_tree(leaf, 1); + btrfs_err(fs_info, + "cannot find raid-stripe for logical [%llu, %llu] devid %llu, profile %s", + logical, logical + *length, stripe->dev->devid, + btrfs_bg_type_to_raid_name(map_type)); + } +free_path: + btrfs_free_path(path); + + return ret; +} diff --git a/fs/btrfs/raid-stripe-tree.h b/fs/btrfs/raid-stripe-tree.h index 9476131a64972..f0f3c99b8a6f2 100644 --- a/fs/btrfs/raid-stripe-tree.h +++ b/fs/btrfs/raid-stripe-tree.h @@ -12,6 +12,9 @@ struct btrfs_ordered_extent; struct btrfs_trans_handle; int btrfs_delete_raid_extent(struct btrfs_trans_handle *trans, u64 start, u64 length); +int btrfs_get_raid_extent_offset(struct btrfs_fs_info *fs_info, + u64 logical, u64 *length, u64 map_type, + u32 stripe_index, struct btrfs_io_stripe *stripe); int btrfs_insert_raid_extent(struct btrfs_trans_handle *trans, struct btrfs_ordered_extent *ordered_extent); @@ -33,4 +36,10 @@ static inline bool btrfs_need_stripe_tree_update(struct btrfs_fs_info *fs_info, return false; } +static inline int btrfs_num_raid_stripes(u32 item_size) +{ + return (item_size - offsetof(struct btrfs_stripe_extent, strides)) / + sizeof(struct btrfs_raid_stride); +} + #endif diff --git a/fs/btrfs/volumes.c b/fs/btrfs/volumes.c index 4f01dec76f1d1..af0abc775b7fd 100644 --- a/fs/btrfs/volumes.c +++ b/fs/btrfs/volumes.c @@ -35,6 +35,7 @@ #include "relocation.h" #include "scrub.h" #include "super.h" +#include "raid-stripe-tree.h" #define BTRFS_BLOCK_GROUP_STRIPE_MASK (BTRFS_BLOCK_GROUP_RAID0 | \ BTRFS_BLOCK_GROUP_RAID10 | \ @@ -6231,12 +6232,20 @@ static u64 btrfs_max_io_len(struct map_lookup *map, enum btrfs_map_op op, return U64_MAX; } -static void set_io_stripe(struct btrfs_io_stripe *dst, const struct map_lookup *map, - u32 stripe_index, u64 stripe_offset, u32 stripe_nr) +static int set_io_stripe(struct btrfs_fs_info *fs_info, enum btrfs_map_op op, + u64 logical, u64 *length, struct btrfs_io_stripe *dst, + struct map_lookup *map, u32 stripe_index, + u64 stripe_offset, u64 stripe_nr) { dst->dev = map->stripes[stripe_index].dev; + + if (op == BTRFS_MAP_READ && btrfs_need_stripe_tree_update(fs_info, map->type)) + return btrfs_get_raid_extent_offset(fs_info, logical, length, + map->type, stripe_index, dst); + dst->physical = map->stripes[stripe_index].physical + stripe_offset + btrfs_stripe_nr_to_offset(stripe_nr); + return 0; } /* @@ -6445,11 +6454,11 @@ int btrfs_map_block(struct btrfs_fs_info *fs_info, enum btrfs_map_op op, */ if (smap && num_alloc_stripes == 1 && !((map->type & BTRFS_BLOCK_GROUP_RAID56_MASK) && mirror_num > 1)) { - set_io_stripe(smap, map, stripe_index, stripe_offset, stripe_nr); + ret = set_io_stripe(fs_info, op, logical, length, smap, map, + stripe_index, stripe_offset, stripe_nr); if (mirror_num_ret) *mirror_num_ret = mirror_num; *bioc_ret = NULL; - ret = 0; goto out; } @@ -6479,22 +6488,35 @@ int btrfs_map_block(struct btrfs_fs_info *fs_info, enum btrfs_map_op op, */ bioc->full_stripe_logical = em->start + btrfs_stripe_nr_to_offset(stripe_nr * data_stripes); - for (i = 0; i < num_stripes; i++) - set_io_stripe(&bioc->stripes[i], map, - (i + stripe_nr) % num_stripes, - stripe_offset, stripe_nr); + for (int i = 0; i < num_stripes; i++) { + ret = set_io_stripe(fs_info, op, logical, length, + &bioc->stripes[i], map, + (i + stripe_nr) % num_stripes, + stripe_offset, stripe_nr); + if (ret < 0) + break; + } } else { /* * For all other non-RAID56 profiles, just copy the target * stripe into the bioc. */ for (i = 0; i < num_stripes; i++) { - set_io_stripe(&bioc->stripes[i], map, stripe_index, - stripe_offset, stripe_nr); + ret = set_io_stripe(fs_info, op, logical, length, + &bioc->stripes[i], map, stripe_index, + stripe_offset, stripe_nr); + if (ret < 0) + break; stripe_index++; } } + if (ret) { + *bioc_ret = NULL; + btrfs_put_bioc(bioc); + goto out; + } + if (op != BTRFS_MAP_READ) max_errors = btrfs_chunk_max_errors(map); -- 2.30.2