From 28810549562d051f0f002590cb6c98b004a09927 Mon Sep 17 00:00:00 2001 From: Josef Bacik Date: Tue, 19 Mar 2013 09:43:13 -0400 Subject: Btrfs-progs: make btrfs-image grab the free space cache A lot of tree log replay bugs are because of strange space cache setups, so make btrfs-image scrape the free space cache as well so we can better replicate what a user is seeing if they have a tree log bug or anything related to free space cache. Thanks, Signed-off-by: Josef Bacik --- btrfs-image.c | 162 ++++++++++++++++++++++++++++++++++++++++++++++++++++++---- 1 file changed, 151 insertions(+), 11 deletions(-) diff --git a/btrfs-image.c b/btrfs-image.c index 0d58bd04..265cbe62 100644 --- a/btrfs-image.c +++ b/btrfs-image.c @@ -34,7 +34,7 @@ #include "transaction.h" #include "utils.h" #include "version.h" - +#include "volumes.h" #define HEADER_MAGIC 0xbd5c25e27295668bULL #define MAX_PENDING_SIZE (256 * 1024) @@ -96,6 +96,7 @@ struct metadump_struct { int compress_level; int done; + int data; }; struct mdrestore_struct { @@ -409,6 +410,60 @@ out: return err; } +static int read_data_extent(struct metadump_struct *md, + struct async_work *async) +{ + struct btrfs_multi_bio *multi = NULL; + struct btrfs_device *device; + u64 bytes_left = async->size; + u64 logical = async->start; + u64 offset = 0; + u64 bytenr; + u64 read_len; + ssize_t done; + int fd; + int ret; + + while (bytes_left) { + read_len = bytes_left; + ret = btrfs_map_block(&md->root->fs_info->mapping_tree, READ, + logical, &read_len, &multi, 0, NULL); + if (ret) { + fprintf(stderr, "Couldn't map data block %d\n", ret); + return ret; + } + + device = multi->stripes[0].dev; + + if (device->fd == 0) { + fprintf(stderr, + "Device we need to read from is not open\n"); + free(multi); + return -EIO; + } + fd = device->fd; + bytenr = multi->stripes[0].physical; + free(multi); + + read_len = min(read_len, bytes_left); + done = pread64(fd, async->buffer+offset, read_len, bytenr); + if (done < read_len) { + if (done < 0) + fprintf(stderr, "Error reading extent %d\n", + errno); + else + fprintf(stderr, "Short read\n"); + return -EIO; + } + + bytes_left -= done; + offset += done; + logical += done; + } + + return 0; +} + static int flush_pending(struct metadump_struct *md, int done) { struct async_work *async = NULL; @@ -435,7 +490,17 @@ static int flush_pending(struct metadump_struct *md, int done) offset = 0; start = async->start; size = async->size; - while (size > 0) { + + if (md->data) { + ret = read_data_extent(md, async); + if (ret) { + free(async->buffer); + free(async); + return ret; + } + } + + while (!md->data && size > 0) { eb = read_tree_block(md->root, start, blocksize, 0); if (!eb) { free(async->buffer); @@ -480,10 +545,12 @@ static int flush_pending(struct metadump_struct *md, int done) return ret; } -static int add_metadata(u64 start, u64 size, struct metadump_struct *md) +static int add_extent(u64 start, u64 size, struct metadump_struct *md, + int data) { int ret; - if (md->pending_size + size > MAX_PENDING_SIZE || + if (md->data != data || + md->pending_size + size > MAX_PENDING_SIZE || md->pending_start + md->pending_size != start) { ret = flush_pending(md, 0); if (ret) @@ -492,6 +559,7 @@ static int add_metadata(u64 start, u64 size, struct metadump_struct *md) } readahead_tree_block(md->root, start, size, 0); md->pending_size += size; + md->data = data; return 0; } @@ -545,7 +613,7 @@ static int copy_log_blocks(struct btrfs_root *root, struct extent_buffer *eb, int i = 0; int ret; - ret = add_metadata(btrfs_header_bytenr(eb), root->leafsize, metadump); + ret = add_extent(btrfs_header_bytenr(eb), root->leafsize, metadump, 0); if (ret) { fprintf(stderr, "Error adding metadata block\n"); return ret; @@ -610,6 +678,72 @@ static int copy_log_trees(struct btrfs_root *root, metadump, 1); } +static int copy_space_cache(struct btrfs_root *root, + struct metadump_struct *metadump, + struct btrfs_path *path) +{ + struct extent_buffer *leaf; + struct btrfs_file_extent_item *fi; + struct btrfs_key key; + u64 bytenr, num_bytes; + int ret; + + root = root->fs_info->tree_root; + + key.objectid = 0; + key.type = BTRFS_EXTENT_DATA_KEY; + key.offset = 0; + + ret = btrfs_search_slot(NULL, root, &key, path, 0, 0); + if (ret < 0) { + fprintf(stderr, "Error searching for free space inode %d\n", + ret); + return ret; + } + + while (1) { + leaf = path->nodes[0]; + if (path->slots[0] >= btrfs_header_nritems(leaf)) { + ret = btrfs_next_leaf(root, path); + if (ret < 0) { + fprintf(stderr, "Error going to next leaf " + "%d\n", ret); + return ret; + } + if (ret > 0) + break; + leaf = path->nodes[0]; + } + + btrfs_item_key_to_cpu(leaf, &key, path->slots[0]); + if (key.type != BTRFS_EXTENT_DATA_KEY) { + path->slots[0]++; + continue; + } + + fi = btrfs_item_ptr(leaf, path->slots[0], + struct btrfs_file_extent_item); + if (btrfs_file_extent_type(leaf, fi) != + BTRFS_FILE_EXTENT_REG) { + path->slots[0]++; + continue; + } + + bytenr = btrfs_file_extent_disk_bytenr(leaf, fi); + num_bytes = btrfs_file_extent_disk_num_bytes(leaf, fi); + ret = add_extent(bytenr, num_bytes, metadump, 1); + if (ret) { + fprintf(stderr, "Error adding space cache blocks %d\n", + ret); + btrfs_release_path(root, path); + return ret; + } + path->slots[0]++; + } + + return 0; +} + static int create_metadump(const char *input, FILE *out, int num_threads, int compress_level) { @@ -641,7 +775,7 @@ static int create_metadump(const char *input, FILE *out, int num_threads, return ret; } - ret = add_metadata(BTRFS_SUPER_INFO_OFFSET, 4096, &metadump); + ret = add_extent(BTRFS_SUPER_INFO_OFFSET, 4096, &metadump, 0); if (ret) { fprintf(stderr, "Error adding metadata %d\n", ret); err = ret; @@ -697,8 +831,8 @@ static int create_metadump(const char *input, FILE *out, int num_threads, struct btrfs_extent_item); if (btrfs_extent_flags(leaf, ei) & BTRFS_EXTENT_FLAG_TREE_BLOCK) { - ret = add_metadata(bytenr, num_bytes, - &metadump); + ret = add_extent(bytenr, num_bytes, &metadump, + 0); if (ret) { fprintf(stderr, "Error adding block " "%d\n", ret); @@ -717,8 +851,8 @@ static int create_metadump(const char *input, FILE *out, int num_threads, } if (ret) { - ret = add_metadata(bytenr, num_bytes, - &metadump); + ret = add_extent(bytenr, num_bytes, &metadump, + 0); if (ret) { fprintf(stderr, "Error adding block " "%d\n", ret); @@ -736,9 +870,15 @@ static int create_metadump(const char *input, FILE *out, int num_threads, bytenr += num_bytes; } + btrfs_release_path(root, path); + ret = copy_log_trees(root, &metadump, path); - if (ret) + if (ret) { err = ret; + goto out; + } + + ret = copy_space_cache(root, &metadump, path); out: ret = flush_pending(&metadump, 1); if (ret) { -- cgit v1.2.3