From 9a8dd1502de6aa683ae46cf0397e9b6e636416fb Mon Sep 17 00:00:00 2001 From: Chris Mason Date: Fri, 23 Feb 2007 08:38:36 -0500 Subject: [PATCH] Btrfs: Block sized tree extents and extent deletion Signed-off-by: Chris Mason --- fs/btrfs/ctree.c | 245 ++++++++++++++++++++++++++++++++++++--------- fs/btrfs/ctree.h | 13 +-- fs/btrfs/disk-io.c | 90 ++++++----------- fs/btrfs/disk-io.h | 2 +- fs/btrfs/mkfs.c | 37 ++++--- 5 files changed, 252 insertions(+), 135 deletions(-) diff --git a/fs/btrfs/ctree.c b/fs/btrfs/ctree.c index 1b4e82d8074d..f0abcf1f3939 100644 --- a/fs/btrfs/ctree.c +++ b/fs/btrfs/ctree.c @@ -8,9 +8,12 @@ #define SEARCH_READ 0 #define SEARCH_WRITE 1 -static int refill_alloc_extent(struct ctree_root *root); +#define CTREE_EXTENT_PENDING 0 + int split_node(struct ctree_root *root, struct ctree_path *path, int level); int split_leaf(struct ctree_root *root, struct ctree_path *path, int data_size); +struct tree_buffer *alloc_free_block(struct ctree_root *root); +int free_extent(struct ctree_root *root, u64 blocknr, u64 num_blocks); static inline void init_path(struct ctree_path *p) { @@ -682,8 +685,6 @@ int insert_item(struct ctree_root *root, struct key *key, unsigned int data_end; struct ctree_path path; - refill_alloc_extent(root); - /* create a root if there isn't one */ if (!root->node) BUG(); @@ -756,6 +757,7 @@ int del_ptr(struct ctree_root *root, struct ctree_path *path, int level) struct tree_buffer *t; struct node *node; int nritems; + u64 blocknr; while(1) { t = path->nodes[level]; @@ -774,6 +776,7 @@ int del_ptr(struct ctree_root *root, struct ctree_path *path, int level) } node->header.nritems--; write_tree_block(root, t); + blocknr = t->blocknr; if (node->header.nritems != 0) { int tslot; if (slot == 0) @@ -799,6 +802,7 @@ int del_ptr(struct ctree_root *root, struct ctree_path *path, int level) break; } level++; + free_extent(root, blocknr, 1); if (!path->nodes[level]) BUG(); } @@ -841,8 +845,10 @@ int del_item(struct ctree_root *root, struct ctree_path *path) if (leaf_buf == root->node) { leaf->header.flags = node_level(0); write_tree_block(root, leaf_buf); - } else + } else { del_ptr(root, path, 1); + free_extent(root, leaf_buf->blocknr, 1); + } } else { if (slot == 0) fixup_low_keys(root, path, &leaf->items[0].key, 1); @@ -867,6 +873,72 @@ int del_item(struct ctree_root *root, struct ctree_path *path) return 0; } +static int del_pending_extents(struct ctree_root *extent_root) +{ + int ret; + struct key key; + struct tree_buffer *gang[4]; + int i; + struct ctree_path path; + + while(1) { + ret = radix_tree_gang_lookup_tag(&extent_root->cache_radix, + (void **)gang, 0, ARRAY_SIZE(gang), + CTREE_EXTENT_PENDING); + if (!ret) + break; + for (i = 0; i < ret; i++) { + key.objectid = gang[i]->blocknr; + key.flags = 0; + key.offset = 1; + init_path(&path); + ret = search_slot(extent_root, &key, &path, 0); + if (ret) { + BUG(); + // FIXME undo it and return sane + return ret; + } + ret = del_item(extent_root, &path); + if (ret) { + BUG(); + return ret; + } + release_path(extent_root, &path); + radix_tree_tag_clear(&extent_root->cache_radix, gang[i]->blocknr, + CTREE_EXTENT_PENDING); + tree_block_release(extent_root, gang[i]); + } + } + return 0; +} + +int free_extent(struct ctree_root *root, u64 blocknr, u64 num_blocks) +{ + struct ctree_path path; + struct key key; + struct ctree_root *extent_root = root->extent_root; + struct tree_buffer *t; + int pending_ret; + int ret; + + key.objectid = blocknr; + key.flags = 0; + key.offset = num_blocks; + if (root == extent_root) { + t = read_tree_block(root, key.objectid); + radix_tree_tag_set(&root->cache_radix, key.objectid, CTREE_EXTENT_PENDING); + return 0; + } + init_path(&path); + ret = search_slot(extent_root, &key, &path, 0); + if (ret) + BUG(); + ret = del_item(extent_root, &path); + release_path(extent_root, &path); + pending_ret = del_pending_extents(root->extent_root); + return ret ? ret : pending_ret; +} + int next_leaf(struct ctree_root *root, struct ctree_path *path) { int slot; @@ -904,8 +976,8 @@ int next_leaf(struct ctree_root *root, struct ctree_path *path) return 0; } -int alloc_extent(struct ctree_root *orig_root, u64 num_blocks, u64 search_start, - u64 search_end, u64 owner, struct key *ins) +int find_free_extent(struct ctree_root *orig_root, u64 num_blocks, u64 search_start, + u64 search_end, struct key *ins) { struct ctree_path path; struct key *key; @@ -915,15 +987,13 @@ int alloc_extent(struct ctree_root *orig_root, u64 num_blocks, u64 search_start, u64 last_block; int start_found = 0; struct leaf *l; - struct extent_item extent_item; struct ctree_root * root = orig_root->extent_root; init_path(&path); ins->objectid = search_start; ins->offset = 0; ins->flags = 0; - - ret = search_slot(root, ins, &path, sizeof(struct extent_item)); + ret = search_slot(root, ins, &path, 0); while (1) { l = &path.nodes[0]->leaf; slot = path.slots[0]; @@ -938,6 +1008,7 @@ int alloc_extent(struct ctree_root *orig_root, u64 num_blocks, u64 search_start, ins->objectid = search_start; ins->offset = num_blocks; hole_size = search_end - search_start; + start_found = 1; goto insert; } ins->objectid = last_block; @@ -956,51 +1027,119 @@ int alloc_extent(struct ctree_root *orig_root, u64 num_blocks, u64 search_start, } else start_found = 1; last_block = key->objectid + key->offset; +insert_failed: path.slots[0]++; } // FIXME -ENOSPC insert: + if (orig_root->extent_root == orig_root) { + BUG_ON(num_blocks != 1); + if ((root->current_insert.objectid <= ins->objectid && + root->current_insert.objectid + root->current_insert.offset > + ins->objectid) || + (root->current_insert.objectid > ins->objectid && + root->current_insert.objectid <= ins->objectid + ins->offset) || + radix_tree_tag_get(&root->cache_radix, ins->objectid, + CTREE_EXTENT_PENDING)) { + last_block = ins->objectid + 1; + search_start = last_block; + goto insert_failed; + } + } release_path(root, &path); + if (ins->offset != 1) + BUG(); + return 0; +} + +static int insert_pending_extents(struct ctree_root *extent_root) +{ + int ret; + struct key key; + struct extent_item item; + struct tree_buffer *gang[4]; + int i; + + // FIXME -ENOSPC + item.refs = 1; + item.owner = extent_root->node->node.header.parentid; + while(1) { + ret = radix_tree_gang_lookup_tag(&extent_root->cache_radix, + (void **)gang, 0, ARRAY_SIZE(gang), + CTREE_EXTENT_PENDING); + if (!ret) + break; + for (i = 0; i < ret; i++) { + key.objectid = gang[i]->blocknr; + key.flags = 0; + key.offset = 1; + ret = insert_item(extent_root, &key, &item, sizeof(item)); + if (ret) { + BUG(); + // FIXME undo it and return sane + return ret; + } + radix_tree_tag_clear(&extent_root->cache_radix, gang[i]->blocknr, + CTREE_EXTENT_PENDING); + tree_block_release(extent_root, gang[i]); + } + } + return 0; +} + +int alloc_extent(struct ctree_root *root, u64 num_blocks, u64 search_start, + u64 search_end, u64 owner, struct key *ins, struct tree_buffer **buf) +{ + int ret; + int pending_ret; + struct extent_item extent_item; + extent_item.refs = 1; extent_item.owner = owner; - if (root == orig_root && root->reserve_extent->num_blocks == 0) { - root->reserve_extent->blocknr = ins->objectid; - root->reserve_extent->num_blocks = ins->offset; - root->reserve_extent->num_used = 0; + + ret = find_free_extent(root, num_blocks, search_start, search_end, ins); + if (ret) + return ret; + + if (root != root->extent_root) { + memcpy(&root->extent_root->current_insert, ins, sizeof(*ins)); + ret = insert_item(root->extent_root, ins, &extent_item, sizeof(extent_item)); + memset(&root->extent_root->current_insert, 0, sizeof(struct key)); + pending_ret = insert_pending_extents(root->extent_root); + if (ret) + return ret; + if (pending_ret) + return pending_ret; + *buf = find_tree_block(root, ins->objectid); + return 0; } - ret = insert_item(root->extent_root, ins, &extent_item, sizeof(extent_item)); - return ret; + /* we're allocating an extent for the extent tree, don't recurse */ + BUG_ON(ins->offset != 1); + *buf = find_tree_block(root, ins->objectid); + BUG_ON(!*buf); + radix_tree_tag_set(&root->cache_radix, ins->objectid, CTREE_EXTENT_PENDING); + (*buf)->count++; + return 0; + } -static int refill_alloc_extent(struct ctree_root *root) +struct tree_buffer *alloc_free_block(struct ctree_root *root) { - struct alloc_extent *ae = root->alloc_extent; - struct key key; + struct key ins; int ret; - int min_blocks = MAX_LEVEL * 2; + struct tree_buffer *buf = NULL; - if (ae->num_blocks > ae->num_used && ae->num_blocks - ae->num_used > - min_blocks) - return 0; - ae = root->reserve_extent; - if (ae->num_blocks > ae->num_used) { - if (root->alloc_extent->num_blocks == 0) { - /* we should swap reserve/alloc_extent when alloc - * fills up - */ - BUG(); - } - if (ae->num_blocks - ae->num_used < min_blocks) - BUG(); - return 0; + ret = alloc_extent(root, 1, 0, (unsigned long)-1, root->node->node.header.parentid, + &ins, &buf); + + if (ret) { + BUG(); + return NULL; } - ret = alloc_extent(root, - min_blocks * 2, 0, (unsigned long)-1, - root->node->node.header.parentid, &key); - ae->blocknr = key.objectid; - ae->num_blocks = key.offset; - ae->num_used = 0; - return ret; + if (root != root->extent_root) + BUG_ON(radix_tree_tag_get(&root->extent_root->cache_radix, buf->blocknr, + CTREE_EXTENT_PENDING)); + return buf; } void print_leaf(struct leaf *l) @@ -1096,6 +1235,7 @@ int main() { print_tree(root, root->node); printf("map tree\n"); print_tree(root->extent_root, root->extent_root->node); + fflush(stdout); srand(55); for (i = 0; i < run_size; i++) { @@ -1111,12 +1251,6 @@ int main() { if (!ret) tree_size++; } - printf("root used: %lu\n", root->alloc_extent->num_used); - printf("root tree\n"); - // print_tree(root, root->node); - printf("map tree\n"); - printf("map used: %lu\n", root->extent_root->alloc_extent->num_used); - // print_tree(root->extent_root, root->extent_root->node); write_ctree_super(root, &super); close_ctree(root); @@ -1167,12 +1301,27 @@ int main() { ret = insert_item(root, &ins, buf, strlen(buf)); if (!ret) tree_size++; + if (i >= 5) { + struct key ugh; + ugh.objectid = 5; + ugh.flags = 0; + ugh.offset = 0; + init_path(&path); + ret = search_slot(root, &ugh, &path, 0); + if (ret) { + print_tree(root, root->node); + printf("unable to find 5 %d\n", num); + exit(1); + } + release_path(root, &path); + + } } write_ctree_super(root, &super); close_ctree(root); root = open_ctree("dbfile", &super); - printf("starting search2\n"); srand(128); + printf("starting search2\n"); for (i = 0; i < run_size; i++) { num = next_key(i, max_key); ins.objectid = num; @@ -1219,5 +1368,7 @@ int main() { write_ctree_super(root, &super); close_ctree(root); printf("tree size is now %d\n", tree_size); + printf("map tree\n"); + print_tree(root->extent_root, root->extent_root->node); return 0; } diff --git a/fs/btrfs/ctree.h b/fs/btrfs/ctree.h index 78407d32db78..8c32c0e9267d 100644 --- a/fs/btrfs/ctree.h +++ b/fs/btrfs/ctree.h @@ -28,21 +28,12 @@ struct header { struct tree_buffer; -struct alloc_extent { - u64 blocknr; - u64 num_blocks; - u64 num_used; -} __attribute__ ((__packed__)); - struct ctree_root { struct tree_buffer *node; struct ctree_root *extent_root; - struct alloc_extent *alloc_extent; - struct alloc_extent *reserve_extent; + struct key current_insert; int fp; struct radix_tree_root cache_radix; - struct alloc_extent ai1; - struct alloc_extent ai2; }; struct ctree_root_info { @@ -52,8 +43,6 @@ struct ctree_root_info { u64 tree_root; /* the tree root */ u32 csum; u32 ham; - struct alloc_extent alloc_extent; - struct alloc_extent reserve_extent; u64 snapuuid[2]; /* root specific uuid */ } __attribute__ ((__packed__)); diff --git a/fs/btrfs/disk-io.c b/fs/btrfs/disk-io.c index a696a4278ac5..14955e440773 100644 --- a/fs/btrfs/disk-io.c +++ b/fs/btrfs/disk-io.c @@ -12,33 +12,13 @@ static int allocated_blocks = 0; -static int get_free_block(struct ctree_root *root, u64 *block) +static int check_tree_block(struct ctree_root *root, struct tree_buffer *buf) { - struct stat st; - int ret = 0; - - if (root->alloc_extent->num_used >= root->alloc_extent->num_blocks) - return -1; - - *block = root->alloc_extent->blocknr + root->alloc_extent->num_used; - root->alloc_extent->num_used += 1; - if (root->alloc_extent->num_used >= root->alloc_extent->num_blocks) { - struct alloc_extent *ae = root->alloc_extent; - root->alloc_extent = root->reserve_extent; - root->reserve_extent = ae; - ae->num_blocks = 0; - } - st.st_size = 0; - ret = fstat(root->fp, &st); - if (st.st_size < (*block + 1) * CTREE_BLOCKSIZE) { - ret = ftruncate(root->fp, - (*block + 1) * CTREE_BLOCKSIZE); - if (ret) { - perror("ftruncate"); - exit(1); - } - } - return ret; + if (buf->blocknr != buf->node.header.blocknr) + BUG(); + if (root->node && buf->node.header.parentid != root->node->node.header.parentid) + BUG(); + return 0; } struct tree_buffer *alloc_tree_block(struct ctree_root *root, u64 blocknr) @@ -61,22 +41,23 @@ struct tree_buffer *alloc_tree_block(struct ctree_root *root, u64 blocknr) return buf; } -struct tree_buffer *alloc_free_block(struct ctree_root *root) +struct tree_buffer *find_tree_block(struct ctree_root *root, u64 blocknr) { - u64 free_block; - int ret; - struct tree_buffer * buf; - ret = get_free_block(root, &free_block); - if (ret) { - BUG(); - return NULL; + struct tree_buffer *buf; + buf = radix_tree_lookup(&root->cache_radix, blocknr); + if (buf) { + buf->count++; + } else { + buf = alloc_tree_block(root, blocknr); + if (!buf) { + BUG(); + return NULL; + } } - buf = alloc_tree_block(root, free_block); - if (!buf) - BUG(); return buf; } + struct tree_buffer *read_tree_block(struct ctree_root *root, u64 blocknr) { loff_t offset = blocknr * CTREE_BLOCKSIZE; @@ -86,20 +67,17 @@ struct tree_buffer *read_tree_block(struct ctree_root *root, u64 blocknr) buf = radix_tree_lookup(&root->cache_radix, blocknr); if (buf) { buf->count++; - goto test; - } - buf = alloc_tree_block(root, blocknr); - if (!buf) - return NULL; - ret = pread(root->fp, &buf->node, CTREE_BLOCKSIZE, offset); - if (ret != CTREE_BLOCKSIZE) { - free(buf); - return NULL; + } else { + buf = alloc_tree_block(root, blocknr); + if (!buf) + return NULL; + ret = pread(root->fp, &buf->node, CTREE_BLOCKSIZE, offset); + if (ret != CTREE_BLOCKSIZE) { + free(buf); + return NULL; + } } -test: - if (buf->blocknr != buf->node.header.blocknr) - BUG(); - if (root->node && buf->node.header.parentid != root->node->node.header.parentid) + if (check_tree_block(root, buf)) BUG(); return buf; } @@ -121,17 +99,10 @@ int write_tree_block(struct ctree_root *root, struct tree_buffer *buf) static int __setup_root(struct ctree_root *root, struct ctree_root *extent_root, struct ctree_root_info *info, int fp) { - INIT_RADIX_TREE(&root->cache_radix, GFP_KERNEL); root->fp = fp; root->node = NULL; root->node = read_tree_block(root, info->tree_root); root->extent_root = extent_root; - memcpy(&root->ai1, &info->alloc_extent, sizeof(info->alloc_extent)); - memcpy(&root->ai2, &info->reserve_extent, sizeof(info->reserve_extent)); - root->alloc_extent = &root->ai1; - root->reserve_extent = &root->ai2; - printf("setup done reading root %p, used %lu available %lu\n", root, root->alloc_extent->num_used, root->alloc_extent->num_blocks); - printf("setup done reading root %p, reserve used %lu available %lu\n", root, root->reserve_extent->num_used, root->reserve_extent->num_blocks); return 0; } @@ -147,6 +118,8 @@ struct ctree_root *open_ctree(char *filename, struct ctree_super_block *super) free(root); return NULL; } + INIT_RADIX_TREE(&root->cache_radix, GFP_KERNEL); + INIT_RADIX_TREE(&extent_root->cache_radix, GFP_KERNEL); ret = pread(fp, super, sizeof(struct ctree_super_block), CTREE_SUPER_INFO_OFFSET(CTREE_BLOCKSIZE)); if (ret == 0 || super->root_info.tree_root == 0) { @@ -168,8 +141,6 @@ struct ctree_root *open_ctree(char *filename, struct ctree_super_block *super) static int __update_root(struct ctree_root *root, struct ctree_root_info *info) { info->tree_root = root->node->blocknr; - memcpy(&info->alloc_extent, root->alloc_extent, sizeof(struct alloc_extent)); - memcpy(&info->reserve_extent, root->reserve_extent, sizeof(struct alloc_extent)); return 0; } @@ -201,6 +172,7 @@ int close_ctree(struct ctree_root *root) void tree_block_release(struct ctree_root *root, struct tree_buffer *buf) { buf->count--; + write_tree_block(root, buf); if (buf->count < 0) BUG(); if (buf->count == 0) { diff --git a/fs/btrfs/disk-io.h b/fs/btrfs/disk-io.h index e288fe883b9a..2729b757ddc1 100644 --- a/fs/btrfs/disk-io.h +++ b/fs/btrfs/disk-io.h @@ -11,11 +11,11 @@ struct tree_buffer { }; struct tree_buffer *read_tree_block(struct ctree_root *root, u64 blocknr); +struct tree_buffer *find_tree_block(struct ctree_root *root, u64 blocknr); int write_tree_block(struct ctree_root *root, struct tree_buffer *buf); struct ctree_root *open_ctree(char *filename, struct ctree_super_block *s); int close_ctree(struct ctree_root *root); void tree_block_release(struct ctree_root *root, struct tree_buffer *buf); -struct tree_buffer *alloc_free_block(struct ctree_root *root); int write_ctree_super(struct ctree_root *root, struct ctree_super_block *s); int mkfs(int fd); diff --git a/fs/btrfs/mkfs.c b/fs/btrfs/mkfs.c index 584aba44e801..fd4e5dea7e1b 100644 --- a/fs/btrfs/mkfs.c +++ b/fs/btrfs/mkfs.c @@ -23,17 +23,10 @@ int mkfs(int fd) info[0].blocknr = 16; info[0].objectid = 1; info[0].tree_root = 17; - info[0].alloc_extent.blocknr = 0; - info[0].alloc_extent.num_blocks = 64; - /* 0-17 are used (inclusive) */ - info[0].alloc_extent.num_used = 18; info[1].blocknr = 16; info[1].objectid = 2; - info[1].tree_root = 64; - info[1].alloc_extent.blocknr = 64; - info[1].alloc_extent.num_blocks = 64; - info[1].alloc_extent.num_used = 1; + info[1].tree_root = 18; ret = pwrite(fd, info, sizeof(info), CTREE_SUPER_INFO_OFFSET(CTREE_BLOCKSIZE)); if (ret != sizeof(info)) @@ -48,24 +41,36 @@ int mkfs(int fd) return -1; empty_leaf.header.parentid = 2; - empty_leaf.header.blocknr = 64; - empty_leaf.header.nritems = 2; + empty_leaf.header.blocknr = 18; + empty_leaf.header.nritems = 3; + + /* item1, reserve blocks 0-16 */ item.key.objectid = 0; - item.key.offset = 64; + item.key.offset = 17; item.key.flags = 0; item.offset = LEAF_DATA_SIZE - sizeof(struct extent_item); item.size = sizeof(struct extent_item); extent_item.refs = 1; - extent_item.owner = 1; + extent_item.owner = 0; memcpy(empty_leaf.items, &item, sizeof(item)); memcpy(empty_leaf.data + item.offset, &extent_item, item.size); - item.key.objectid = 64; - item.key.offset = 64; + + /* item2, give block 17 to the root */ + item.key.objectid = 17; + item.key.offset = 1; item.offset = LEAF_DATA_SIZE - sizeof(struct extent_item) * 2; - extent_item.owner = 2; + extent_item.owner = 1; memcpy(empty_leaf.items + 1, &item, sizeof(item)); memcpy(empty_leaf.data + item.offset, &extent_item, item.size); - ret = pwrite(fd, &empty_leaf, sizeof(empty_leaf), 64 * CTREE_BLOCKSIZE); + + /* item3, give block 18 for the extent root */ + item.key.objectid = 18; + item.key.offset = 1; + item.offset = LEAF_DATA_SIZE - sizeof(struct extent_item) * 3; + extent_item.owner = 2; + memcpy(empty_leaf.items + 2, &item, sizeof(item)); + memcpy(empty_leaf.data + item.offset, &extent_item, item.size); + ret = pwrite(fd, &empty_leaf, sizeof(empty_leaf), 18 * CTREE_BLOCKSIZE); if (ret != sizeof(empty_leaf)) return -1; return 0; -- 2.20.1