diff --git a/fs/btrfs/Makefile b/fs/btrfs/Makefile index bdd6fb238ce1..c0ddfd29c5e5 100644 --- a/fs/btrfs/Makefile +++ b/fs/btrfs/Makefile @@ -8,6 +8,6 @@ btrfs-y += super.o ctree.o extent-tree.o print-tree.o root-tree.o dir-item.o \ extent_io.o volumes.o async-thread.o ioctl.o locking.o orphan.o \ export.o tree-log.o free-space-cache.o zlib.o lzo.o \ compression.o delayed-ref.o relocation.o delayed-inode.o scrub.o \ - reada.o + reada.o backref.o btrfs-$(CONFIG_BTRFS_FS_POSIX_ACL) += acl.o diff --git a/fs/btrfs/backref.c b/fs/btrfs/backref.c new file mode 100644 index 000000000000..2351df0de450 --- /dev/null +++ b/fs/btrfs/backref.c @@ -0,0 +1,776 @@ +/* + * Copyright (C) 2011 STRATO. All rights reserved. + * + * This program is free software; you can redistribute it and/or + * modify it under the terms of the GNU General Public + * License v2 as published by the Free Software Foundation. + * + * This program is distributed in the hope that it will be useful, + * but WITHOUT ANY WARRANTY; without even the implied warranty of + * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU + * General Public License for more details. + * + * You should have received a copy of the GNU General Public + * License along with this program; if not, write to the + * Free Software Foundation, Inc., 59 Temple Place - Suite 330, + * Boston, MA 021110-1307, USA. + */ + +#include "ctree.h" +#include "disk-io.h" +#include "backref.h" + +struct __data_ref { + struct list_head list; + u64 inum; + u64 root; + u64 extent_data_item_offset; +}; + +struct __shared_ref { + struct list_head list; + u64 disk_byte; +}; + +static int __inode_info(u64 inum, u64 ioff, u8 key_type, + struct btrfs_root *fs_root, struct btrfs_path *path, + struct btrfs_key *found_key) +{ + int ret; + struct btrfs_key key; + struct extent_buffer *eb; + + key.type = key_type; + key.objectid = inum; + key.offset = ioff; + + ret = btrfs_search_slot(NULL, fs_root, &key, path, 0, 0); + if (ret < 0) + return ret; + + eb = path->nodes[0]; + if (ret && path->slots[0] >= btrfs_header_nritems(eb)) { + ret = btrfs_next_leaf(fs_root, path); + if (ret) + return ret; + eb = path->nodes[0]; + } + + btrfs_item_key_to_cpu(eb, found_key, path->slots[0]); + if (found_key->type != key.type || found_key->objectid != key.objectid) + return 1; + + return 0; +} + +/* + * this makes the path point to (inum INODE_ITEM ioff) + */ +int inode_item_info(u64 inum, u64 ioff, struct btrfs_root *fs_root, + struct btrfs_path *path) +{ + struct btrfs_key key; + return __inode_info(inum, ioff, BTRFS_INODE_ITEM_KEY, fs_root, path, + &key); +} + +static int inode_ref_info(u64 inum, u64 ioff, struct btrfs_root *fs_root, + struct btrfs_path *path, + struct btrfs_key *found_key) +{ + return __inode_info(inum, ioff, BTRFS_INODE_REF_KEY, fs_root, path, + found_key); +} + +/* + * this iterates to turn a btrfs_inode_ref into a full filesystem path. elements + * of the path are separated by '/' and the path is guaranteed to be + * 0-terminated. the path is only given within the current file system. + * Therefore, it never starts with a '/'. the caller is responsible to provide + * "size" bytes in "dest". the dest buffer will be filled backwards. finally, + * the start point of the resulting string is returned. this pointer is within + * dest, normally. + * in case the path buffer would overflow, the pointer is decremented further + * as if output was written to the buffer, though no more output is actually + * generated. that way, the caller can determine how much space would be + * required for the path to fit into the buffer. in that case, the returned + * value will be smaller than dest. callers must check this! + */ +static char *iref_to_path(struct btrfs_root *fs_root, struct btrfs_path *path, + struct btrfs_inode_ref *iref, + struct extent_buffer *eb_in, u64 parent, + char *dest, u32 size) +{ + u32 len; + int slot; + u64 next_inum; + int ret; + s64 bytes_left = size - 1; + struct extent_buffer *eb = eb_in; + struct btrfs_key found_key; + + if (bytes_left >= 0) + dest[bytes_left] = '\0'; + + while (1) { + len = btrfs_inode_ref_name_len(eb, iref); + bytes_left -= len; + if (bytes_left >= 0) + read_extent_buffer(eb, dest + bytes_left, + (unsigned long)(iref + 1), len); + if (eb != eb_in) + free_extent_buffer(eb); + ret = inode_ref_info(parent, 0, fs_root, path, &found_key); + if (ret) + break; + next_inum = found_key.offset; + + /* regular exit ahead */ + if (parent == next_inum) + break; + + slot = path->slots[0]; + eb = path->nodes[0]; + /* make sure we can use eb after releasing the path */ + if (eb != eb_in) + atomic_inc(&eb->refs); + btrfs_release_path(path); + + iref = btrfs_item_ptr(eb, slot, struct btrfs_inode_ref); + parent = next_inum; + --bytes_left; + if (bytes_left >= 0) + dest[bytes_left] = '/'; + } + + btrfs_release_path(path); + + if (ret) + return ERR_PTR(ret); + + return dest + bytes_left; +} + +/* + * this makes the path point to (logical EXTENT_ITEM *) + * returns BTRFS_EXTENT_FLAG_DATA for data, BTRFS_EXTENT_FLAG_TREE_BLOCK for + * tree blocks and <0 on error. + */ +int extent_from_logical(struct btrfs_fs_info *fs_info, u64 logical, + struct btrfs_path *path, struct btrfs_key *found_key) +{ + int ret; + u64 flags; + u32 item_size; + struct extent_buffer *eb; + struct btrfs_extent_item *ei; + struct btrfs_key key; + + key.type = BTRFS_EXTENT_ITEM_KEY; + key.objectid = logical; + key.offset = (u64)-1; + + ret = btrfs_search_slot(NULL, fs_info->extent_root, &key, path, 0, 0); + if (ret < 0) + return ret; + ret = btrfs_previous_item(fs_info->extent_root, path, + 0, BTRFS_EXTENT_ITEM_KEY); + if (ret < 0) + return ret; + + btrfs_item_key_to_cpu(path->nodes[0], found_key, path->slots[0]); + if (found_key->type != BTRFS_EXTENT_ITEM_KEY || + found_key->objectid > logical || + found_key->objectid + found_key->offset <= logical) + return -ENOENT; + + eb = path->nodes[0]; + item_size = btrfs_item_size_nr(eb, path->slots[0]); + BUG_ON(item_size < sizeof(*ei)); + + ei = btrfs_item_ptr(eb, path->slots[0], struct btrfs_extent_item); + flags = btrfs_extent_flags(eb, ei); + + if (flags & BTRFS_EXTENT_FLAG_TREE_BLOCK) + return BTRFS_EXTENT_FLAG_TREE_BLOCK; + if (flags & BTRFS_EXTENT_FLAG_DATA) + return BTRFS_EXTENT_FLAG_DATA; + + return -EIO; +} + +/* + * helper function to iterate extent inline refs. ptr must point to a 0 value + * for the first call and may be modified. it is used to track state. + * if more refs exist, 0 is returned and the next call to + * __get_extent_inline_ref must pass the modified ptr parameter to get the + * next ref. after the last ref was processed, 1 is returned. + * returns <0 on error + */ +static int __get_extent_inline_ref(unsigned long *ptr, struct extent_buffer *eb, + struct btrfs_extent_item *ei, u32 item_size, + struct btrfs_extent_inline_ref **out_eiref, + int *out_type) +{ + unsigned long end; + u64 flags; + struct btrfs_tree_block_info *info; + + if (!*ptr) { + /* first call */ + flags = btrfs_extent_flags(eb, ei); + if (flags & BTRFS_EXTENT_FLAG_TREE_BLOCK) { + info = (struct btrfs_tree_block_info *)(ei + 1); + *out_eiref = + (struct btrfs_extent_inline_ref *)(info + 1); + } else { + *out_eiref = (struct btrfs_extent_inline_ref *)(ei + 1); + } + *ptr = (unsigned long)*out_eiref; + if ((void *)*ptr >= (void *)ei + item_size) + return -ENOENT; + } + + end = (unsigned long)ei + item_size; + *out_eiref = (struct btrfs_extent_inline_ref *)*ptr; + *out_type = btrfs_extent_inline_ref_type(eb, *out_eiref); + + *ptr += btrfs_extent_inline_ref_size(*out_type); + WARN_ON(*ptr > end); + if (*ptr == end) + return 1; /* last */ + + return 0; +} + +/* + * reads the tree block backref for an extent. tree level and root are returned + * through out_level and out_root. ptr must point to a 0 value for the first + * call and may be modified (see __get_extent_inline_ref comment). + * returns 0 if data was provided, 1 if there was no more data to provide or + * <0 on error. + */ +int tree_backref_for_extent(unsigned long *ptr, struct extent_buffer *eb, + struct btrfs_extent_item *ei, u32 item_size, + u64 *out_root, u8 *out_level) +{ + int ret; + int type; + struct btrfs_tree_block_info *info; + struct btrfs_extent_inline_ref *eiref; + + if (*ptr == (unsigned long)-1) + return 1; + + while (1) { + ret = __get_extent_inline_ref(ptr, eb, ei, item_size, + &eiref, &type); + if (ret < 0) + return ret; + + if (type == BTRFS_TREE_BLOCK_REF_KEY || + type == BTRFS_SHARED_BLOCK_REF_KEY) + break; + + if (ret == 1) + return 1; + } + + /* we can treat both ref types equally here */ + info = (struct btrfs_tree_block_info *)(ei + 1); + *out_root = btrfs_extent_inline_ref_offset(eb, eiref); + *out_level = btrfs_tree_block_level(eb, info); + + if (ret == 1) + *ptr = (unsigned long)-1; + + return 0; +} + +static int __data_list_add(struct list_head *head, u64 inum, + u64 extent_data_item_offset, u64 root) +{ + struct __data_ref *ref; + + ref = kmalloc(sizeof(*ref), GFP_NOFS); + if (!ref) + return -ENOMEM; + + ref->inum = inum; + ref->extent_data_item_offset = extent_data_item_offset; + ref->root = root; + list_add_tail(&ref->list, head); + + return 0; +} + +static int __data_list_add_eb(struct list_head *head, struct extent_buffer *eb, + struct btrfs_extent_data_ref *dref) +{ + return __data_list_add(head, btrfs_extent_data_ref_objectid(eb, dref), + btrfs_extent_data_ref_offset(eb, dref), + btrfs_extent_data_ref_root(eb, dref)); +} + +static int __shared_list_add(struct list_head *head, u64 disk_byte) +{ + struct __shared_ref *ref; + + ref = kmalloc(sizeof(*ref), GFP_NOFS); + if (!ref) + return -ENOMEM; + + ref->disk_byte = disk_byte; + list_add_tail(&ref->list, head); + + return 0; +} + +static int __iter_shared_inline_ref_inodes(struct btrfs_fs_info *fs_info, + u64 logical, u64 inum, + u64 extent_data_item_offset, + u64 extent_offset, + struct btrfs_path *path, + struct list_head *data_refs, + iterate_extent_inodes_t *iterate, + void *ctx) +{ + u64 ref_root; + u32 item_size; + struct btrfs_key key; + struct extent_buffer *eb; + struct btrfs_extent_item *ei; + struct btrfs_extent_inline_ref *eiref; + struct __data_ref *ref; + int ret; + int type; + int last; + unsigned long ptr = 0; + + WARN_ON(!list_empty(data_refs)); + ret = extent_from_logical(fs_info, logical, path, &key); + if (ret & BTRFS_EXTENT_FLAG_DATA) + ret = -EIO; + if (ret < 0) + goto out; + + eb = path->nodes[0]; + ei = btrfs_item_ptr(eb, path->slots[0], struct btrfs_extent_item); + item_size = btrfs_item_size_nr(eb, path->slots[0]); + + ret = 0; + ref_root = 0; + /* + * as done in iterate_extent_inodes, we first build a list of refs to + * iterate, then free the path and then iterate them to avoid deadlocks. + */ + do { + last = __get_extent_inline_ref(&ptr, eb, ei, item_size, + &eiref, &type); + if (last < 0) { + ret = last; + goto out; + } + if (type == BTRFS_TREE_BLOCK_REF_KEY || + type == BTRFS_SHARED_BLOCK_REF_KEY) { + ref_root = btrfs_extent_inline_ref_offset(eb, eiref); + ret = __data_list_add(data_refs, inum, + extent_data_item_offset, + ref_root); + } + } while (!ret && !last); + + btrfs_release_path(path); + + if (ref_root == 0) { + printk(KERN_ERR "btrfs: failed to find tree block ref " + "for shared data backref %llu\n", logical); + WARN_ON(1); + ret = -EIO; + } + +out: + while (!list_empty(data_refs)) { + ref = list_first_entry(data_refs, struct __data_ref, list); + list_del(&ref->list); + if (!ret) + ret = iterate(ref->inum, extent_offset + + ref->extent_data_item_offset, + ref->root, ctx); + kfree(ref); + } + + return ret; +} + +static int __iter_shared_inline_ref(struct btrfs_fs_info *fs_info, + u64 logical, u64 orig_extent_item_objectid, + u64 extent_offset, struct btrfs_path *path, + struct list_head *data_refs, + iterate_extent_inodes_t *iterate, + void *ctx) +{ + u64 disk_byte; + struct btrfs_key key; + struct btrfs_file_extent_item *fi; + struct extent_buffer *eb; + int slot; + int nritems; + int ret; + int found = 0; + + eb = read_tree_block(fs_info->tree_root, logical, + fs_info->tree_root->leafsize, 0); + if (!eb) + return -EIO; + + /* + * from the shared data ref, we only have the leaf but we need + * the key. thus, we must look into all items and see that we + * find one (some) with a reference to our extent item. + */ + nritems = btrfs_header_nritems(eb); + for (slot = 0; slot < nritems; ++slot) { + btrfs_item_key_to_cpu(eb, &key, slot); + if (key.type != BTRFS_EXTENT_DATA_KEY) + continue; + fi = btrfs_item_ptr(eb, slot, struct btrfs_file_extent_item); + if (!fi) { + free_extent_buffer(eb); + return -EIO; + } + disk_byte = btrfs_file_extent_disk_bytenr(eb, fi); + if (disk_byte != orig_extent_item_objectid) { + if (found) + break; + else + continue; + } + ++found; + ret = __iter_shared_inline_ref_inodes(fs_info, logical, + key.objectid, + key.offset, + extent_offset, path, + data_refs, + iterate, ctx); + if (ret) + break; + } + + if (!found) { + printk(KERN_ERR "btrfs: failed to follow shared data backref " + "to parent %llu\n", logical); + WARN_ON(1); + ret = -EIO; + } + + free_extent_buffer(eb); + return ret; +} + +/* + * calls iterate() for every inode that references the extent identified by + * the given parameters. will use the path given as a parameter and return it + * released. + * when the iterator function returns a non-zero value, iteration stops. + */ +int iterate_extent_inodes(struct btrfs_fs_info *fs_info, + struct btrfs_path *path, + u64 extent_item_objectid, + u64 extent_offset, + iterate_extent_inodes_t *iterate, void *ctx) +{ + unsigned long ptr = 0; + int last; + int ret; + int type; + u64 logical; + u32 item_size; + struct btrfs_extent_inline_ref *eiref; + struct btrfs_extent_data_ref *dref; + struct extent_buffer *eb; + struct btrfs_extent_item *ei; + struct btrfs_key key; + struct list_head data_refs = LIST_HEAD_INIT(data_refs); + struct list_head shared_refs = LIST_HEAD_INIT(shared_refs); + struct __data_ref *ref_d; + struct __shared_ref *ref_s; + + eb = path->nodes[0]; + ei = btrfs_item_ptr(eb, path->slots[0], struct btrfs_extent_item); + item_size = btrfs_item_size_nr(eb, path->slots[0]); + + /* first we iterate the inline refs, ... */ + do { + last = __get_extent_inline_ref(&ptr, eb, ei, item_size, + &eiref, &type); + if (last == -ENOENT) { + ret = 0; + break; + } + if (last < 0) { + ret = last; + break; + } + + if (type == BTRFS_EXTENT_DATA_REF_KEY) { + dref = (struct btrfs_extent_data_ref *)(&eiref->offset); + ret = __data_list_add_eb(&data_refs, eb, dref); + } else if (type == BTRFS_SHARED_DATA_REF_KEY) { + logical = btrfs_extent_inline_ref_offset(eb, eiref); + ret = __shared_list_add(&shared_refs, logical); + } + } while (!ret && !last); + + /* ... then we proceed to in-tree references and ... */ + while (!ret) { + ++path->slots[0]; + if (path->slots[0] > btrfs_header_nritems(eb)) { + ret = btrfs_next_leaf(fs_info->extent_root, path); + if (ret) { + if (ret == 1) + ret = 0; /* we're done */ + break; + } + eb = path->nodes[0]; + } + btrfs_item_key_to_cpu(eb, &key, path->slots[0]); + if (key.objectid != extent_item_objectid) + break; + if (key.type == BTRFS_EXTENT_DATA_REF_KEY) { + dref = btrfs_item_ptr(eb, path->slots[0], + struct btrfs_extent_data_ref); + ret = __data_list_add_eb(&data_refs, eb, dref); + } else if (key.type == BTRFS_SHARED_DATA_REF_KEY) { + ret = __shared_list_add(&shared_refs, key.offset); + } + } + + btrfs_release_path(path); + + /* + * ... only at the very end we can process the refs we found. this is + * because the iterator function we call is allowed to make tree lookups + * and we have to avoid deadlocks. additionally, we need more tree + * lookups ourselves for shared data refs. + */ + while (!list_empty(&data_refs)) { + ref_d = list_first_entry(&data_refs, struct __data_ref, list); + list_del(&ref_d->list); + if (!ret) + ret = iterate(ref_d->inum, extent_offset + + ref_d->extent_data_item_offset, + ref_d->root, ctx); + kfree(ref_d); + } + + while (!list_empty(&shared_refs)) { + ref_s = list_first_entry(&shared_refs, struct __shared_ref, + list); + list_del(&ref_s->list); + if (!ret) + ret = __iter_shared_inline_ref(fs_info, + ref_s->disk_byte, + extent_item_objectid, + extent_offset, path, + &data_refs, + iterate, ctx); + kfree(ref_s); + } + + return ret; +} + +int iterate_inodes_from_logical(u64 logical, struct btrfs_fs_info *fs_info, + struct btrfs_path *path, + iterate_extent_inodes_t *iterate, void *ctx) +{ + int ret; + u64 offset; + struct btrfs_key found_key; + + ret = extent_from_logical(fs_info, logical, path, + &found_key); + if (ret & BTRFS_EXTENT_FLAG_TREE_BLOCK) + ret = -EINVAL; + if (ret < 0) + return ret; + + offset = logical - found_key.objectid; + ret = iterate_extent_inodes(fs_info, path, found_key.objectid, + offset, iterate, ctx); + + return ret; +} + +static int iterate_irefs(u64 inum, struct btrfs_root *fs_root, + struct btrfs_path *path, + iterate_irefs_t *iterate, void *ctx) +{ + int ret; + int slot; + u32 cur; + u32 len; + u32 name_len; + u64 parent = 0; + int found = 0; + struct extent_buffer *eb; + struct btrfs_item *item; + struct btrfs_inode_ref *iref; + struct btrfs_key found_key; + + while (1) { + ret = inode_ref_info(inum, parent ? parent+1 : 0, fs_root, path, + &found_key); + if (ret < 0) + break; + if (ret) { + ret = found ? 0 : -ENOENT; + break; + } + ++found; + + parent = found_key.offset; + slot = path->slots[0]; + eb = path->nodes[0]; + /* make sure we can use eb after releasing the path */ + atomic_inc(&eb->refs); + btrfs_release_path(path); + + item = btrfs_item_nr(eb, slot); + iref = btrfs_item_ptr(eb, slot, struct btrfs_inode_ref); + + for (cur = 0; cur < btrfs_item_size(eb, item); cur += len) { + name_len = btrfs_inode_ref_name_len(eb, iref); + /* path must be released before calling iterate()! */ + ret = iterate(parent, iref, eb, ctx); + if (ret) { + free_extent_buffer(eb); + break; + } + len = sizeof(*iref) + name_len; + iref = (struct btrfs_inode_ref *)((char *)iref + len); + } + free_extent_buffer(eb); + } + + btrfs_release_path(path); + + return ret; +} + +/* + * returns 0 if the path could be dumped (probably truncated) + * returns <0 in case of an error + */ +static int inode_to_path(u64 inum, struct btrfs_inode_ref *iref, + struct extent_buffer *eb, void *ctx) +{ + struct inode_fs_paths *ipath = ctx; + char *fspath; + char *fspath_min; + int i = ipath->fspath->elem_cnt; + const int s_ptr = sizeof(char *); + u32 bytes_left; + + bytes_left = ipath->fspath->bytes_left > s_ptr ? + ipath->fspath->bytes_left - s_ptr : 0; + + fspath_min = (char *)ipath->fspath->str + (i + 1) * s_ptr; + fspath = iref_to_path(ipath->fs_root, ipath->btrfs_path, iref, eb, + inum, fspath_min, bytes_left); + if (IS_ERR(fspath)) + return PTR_ERR(fspath); + + if (fspath > fspath_min) { + ipath->fspath->str[i] = fspath; + ++ipath->fspath->elem_cnt; + ipath->fspath->bytes_left = fspath - fspath_min; + } else { + ++ipath->fspath->elem_missed; + ipath->fspath->bytes_missing += fspath_min - fspath; + ipath->fspath->bytes_left = 0; + } + + return 0; +} + +/* + * this dumps all file system paths to the inode into the ipath struct, provided + * is has been created large enough. each path is zero-terminated and accessed + * from ipath->fspath->str[i]. + * when it returns, there are ipath->fspath->elem_cnt number of paths available + * in ipath->fspath->str[]. when the allocated space wasn't sufficient, the + * number of missed paths in recored in ipath->fspath->elem_missed, otherwise, + * it's zero. ipath->fspath->bytes_missing holds the number of bytes that would + * have been needed to return all paths. + */ +int paths_from_inode(u64 inum, struct inode_fs_paths *ipath) +{ + return iterate_irefs(inum, ipath->fs_root, ipath->btrfs_path, + inode_to_path, ipath); +} + +/* + * allocates space to return multiple file system paths for an inode. + * total_bytes to allocate are passed, note that space usable for actual path + * information will be total_bytes - sizeof(struct inode_fs_paths). + * the returned pointer must be freed with free_ipath() in the end. + */ +struct btrfs_data_container *init_data_container(u32 total_bytes) +{ + struct btrfs_data_container *data; + size_t alloc_bytes; + + alloc_bytes = max_t(size_t, total_bytes, sizeof(*data)); + data = kmalloc(alloc_bytes, GFP_NOFS); + if (!data) + return ERR_PTR(-ENOMEM); + + if (total_bytes >= sizeof(*data)) { + data->bytes_left = total_bytes - sizeof(*data); + data->bytes_missing = 0; + } else { + data->bytes_missing = sizeof(*data) - total_bytes; + data->bytes_left = 0; + } + + data->elem_cnt = 0; + data->elem_missed = 0; + + return data; +} + +/* + * allocates space to return multiple file system paths for an inode. + * total_bytes to allocate are passed, note that space usable for actual path + * information will be total_bytes - sizeof(struct inode_fs_paths). + * the returned pointer must be freed with free_ipath() in the end. + */ +struct inode_fs_paths *init_ipath(s32 total_bytes, struct btrfs_root *fs_root, + struct btrfs_path *path) +{ + struct inode_fs_paths *ifp; + struct btrfs_data_container *fspath; + + fspath = init_data_container(total_bytes); + if (IS_ERR(fspath)) + return (void *)fspath; + + ifp = kmalloc(sizeof(*ifp), GFP_NOFS); + if (!ifp) { + kfree(fspath); + return ERR_PTR(-ENOMEM); + } + + ifp->btrfs_path = path; + ifp->fspath = fspath; + ifp->fs_root = fs_root; + + return ifp; +} + +void free_ipath(struct inode_fs_paths *ipath) +{ + kfree(ipath); +} diff --git a/fs/btrfs/backref.h b/fs/btrfs/backref.h new file mode 100644 index 000000000000..92618837cb8f --- /dev/null +++ b/fs/btrfs/backref.h @@ -0,0 +1,62 @@ +/* + * Copyright (C) 2011 STRATO. All rights reserved. + * + * This program is free software; you can redistribute it and/or + * modify it under the terms of the GNU General Public + * License v2 as published by the Free Software Foundation. + * + * This program is distributed in the hope that it will be useful, + * but WITHOUT ANY WARRANTY; without even the implied warranty of + * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU + * General Public License for more details. + * + * You should have received a copy of the GNU General Public + * License along with this program; if not, write to the + * Free Software Foundation, Inc., 59 Temple Place - Suite 330, + * Boston, MA 021110-1307, USA. + */ + +#ifndef __BTRFS_BACKREF__ +#define __BTRFS_BACKREF__ + +#include "ioctl.h" + +struct inode_fs_paths { + struct btrfs_path *btrfs_path; + struct btrfs_root *fs_root; + struct btrfs_data_container *fspath; +}; + +typedef int (iterate_extent_inodes_t)(u64 inum, u64 offset, u64 root, + void *ctx); +typedef int (iterate_irefs_t)(u64 parent, struct btrfs_inode_ref *iref, + struct extent_buffer *eb, void *ctx); + +int inode_item_info(u64 inum, u64 ioff, struct btrfs_root *fs_root, + struct btrfs_path *path); + +int extent_from_logical(struct btrfs_fs_info *fs_info, u64 logical, + struct btrfs_path *path, struct btrfs_key *found_key); + +int tree_backref_for_extent(unsigned long *ptr, struct extent_buffer *eb, + struct btrfs_extent_item *ei, u32 item_size, + u64 *out_root, u8 *out_level); + +int iterate_extent_inodes(struct btrfs_fs_info *fs_info, + struct btrfs_path *path, + u64 extent_item_objectid, + u64 extent_offset, + iterate_extent_inodes_t *iterate, void *ctx); + +int iterate_inodes_from_logical(u64 logical, struct btrfs_fs_info *fs_info, + struct btrfs_path *path, + iterate_extent_inodes_t *iterate, void *ctx); + +int paths_from_inode(u64 inum, struct inode_fs_paths *ipath); + +struct btrfs_data_container *init_data_container(u32 total_bytes); +struct inode_fs_paths *init_ipath(s32 total_bytes, struct btrfs_root *fs_root, + struct btrfs_path *path); +void free_ipath(struct inode_fs_paths *ipath); + +#endif diff --git a/fs/btrfs/disk-io.c b/fs/btrfs/disk-io.c index cedfbfb278eb..0eb1f0951251 100644 --- a/fs/btrfs/disk-io.c +++ b/fs/btrfs/disk-io.c @@ -620,7 +620,7 @@ out: static int btree_io_failed_hook(struct bio *failed_bio, struct page *page, u64 start, u64 end, - struct extent_state *state) + u64 mirror_num, struct extent_state *state) { struct extent_io_tree *tree; unsigned long len; @@ -944,7 +944,7 @@ static int btree_readpage(struct file *file, struct page *page) { struct extent_io_tree *tree; tree = &BTRFS_I(page->mapping->host)->io_tree; - return extent_read_full_page(tree, page, btree_get_extent); + return extent_read_full_page(tree, page, btree_get_extent, 0); } static int btree_releasepage(struct page *page, gfp_t gfp_flags) diff --git a/fs/btrfs/extent-tree.c b/fs/btrfs/extent-tree.c index 23e936c3de76..18ea90c8943b 100644 --- a/fs/btrfs/extent-tree.c +++ b/fs/btrfs/extent-tree.c @@ -1788,18 +1788,18 @@ static int btrfs_discard_extent(struct btrfs_root *root, u64 bytenr, { int ret; u64 discarded_bytes = 0; - struct btrfs_multi_bio *multi = NULL; + struct btrfs_bio *bbio = NULL; /* Tell the block device(s) that the sectors can be discarded */ ret = btrfs_map_block(&root->fs_info->mapping_tree, REQ_DISCARD, - bytenr, &num_bytes, &multi, 0); + bytenr, &num_bytes, &bbio, 0); if (!ret) { - struct btrfs_bio_stripe *stripe = multi->stripes; + struct btrfs_bio_stripe *stripe = bbio->stripes; int i; - for (i = 0; i < multi->num_stripes; i++, stripe++) { + for (i = 0; i < bbio->num_stripes; i++, stripe++) { if (!stripe->dev->can_discard) continue; @@ -1818,7 +1818,7 @@ static int btrfs_discard_extent(struct btrfs_root *root, u64 bytenr, */ ret = 0; } - kfree(multi); + kfree(bbio); } if (actual_bytes) diff --git a/fs/btrfs/extent_io.c b/fs/btrfs/extent_io.c index c12705682c65..1f87c4d0e7a0 100644 --- a/fs/btrfs/extent_io.c +++ b/fs/btrfs/extent_io.c @@ -17,6 +17,7 @@ #include "compat.h" #include "ctree.h" #include "btrfs_inode.h" +#include "volumes.h" static struct kmem_cache *extent_state_cache; static struct kmem_cache *extent_buffer_cache; @@ -1787,6 +1788,368 @@ static int check_page_writeback(struct extent_io_tree *tree, return 0; } +/* + * When IO fails, either with EIO or csum verification fails, we + * try other mirrors that might have a good copy of the data. This + * io_failure_record is used to record state as we go through all the + * mirrors. If another mirror has good data, the page is set up to date + * and things continue. If a good mirror can't be found, the original + * bio end_io callback is called to indicate things have failed. + */ +struct io_failure_record { + struct page *page; + u64 start; + u64 len; + u64 logical; + unsigned long bio_flags; + int this_mirror; + int failed_mirror; + int in_validation; +}; + +static int free_io_failure(struct inode *inode, struct io_failure_record *rec, + int did_repair) +{ + int ret; + int err = 0; + struct extent_io_tree *failure_tree = &BTRFS_I(inode)->io_failure_tree; + + set_state_private(failure_tree, rec->start, 0); + ret = clear_extent_bits(failure_tree, rec->start, + rec->start + rec->len - 1, + EXTENT_LOCKED | EXTENT_DIRTY, GFP_NOFS); + if (ret) + err = ret; + + if (did_repair) { + ret = clear_extent_bits(&BTRFS_I(inode)->io_tree, rec->start, + rec->start + rec->len - 1, + EXTENT_DAMAGED, GFP_NOFS); + if (ret && !err) + err = ret; + } + + kfree(rec); + return err; +} + +static void repair_io_failure_callback(struct bio *bio, int err) +{ + complete(bio->bi_private); +} + +/* + * this bypasses the standard btrfs submit functions deliberately, as + * the standard behavior is to write all copies in a raid setup. here we only + * want to write the one bad copy. so we do the mapping for ourselves and issue + * submit_bio directly. + * to avoid any synchonization issues, wait for the data after writing, which + * actually prevents the read that triggered the error from finishing. + * currently, there can be no more than two copies of every data bit. thus, + * exactly one rewrite is required. + */ +int repair_io_failure(struct btrfs_mapping_tree *map_tree, u64 start, + u64 length, u64 logical, struct page *page, + int mirror_num) +{ + struct bio *bio; + struct btrfs_device *dev; + DECLARE_COMPLETION_ONSTACK(compl); + u64 map_length = 0; + u64 sector; + struct btrfs_bio *bbio = NULL; + int ret; + + BUG_ON(!mirror_num); + + bio = bio_alloc(GFP_NOFS, 1); + if (!bio) + return -EIO; + bio->bi_private = &compl; + bio->bi_end_io = repair_io_failure_callback; + bio->bi_size = 0; + map_length = length; + + ret = btrfs_map_block(map_tree, WRITE, logical, + &map_length, &bbio, mirror_num); + if (ret) { + bio_put(bio); + return -EIO; + } + BUG_ON(mirror_num != bbio->mirror_num); + sector = bbio->stripes[mirror_num-1].physical >> 9; + bio->bi_sector = sector; + dev = bbio->stripes[mirror_num-1].dev; + kfree(bbio); + if (!dev || !dev->bdev || !dev->writeable) { + bio_put(bio); + return -EIO; + } + bio->bi_bdev = dev->bdev; + bio_add_page(bio, page, length, start-page_offset(page)); + submit_bio(WRITE_SYNC, bio); + wait_for_completion(&compl); + + if (!test_bit(BIO_UPTODATE, &bio->bi_flags)) { + /* try to remap that extent elsewhere? */ + bio_put(bio); + return -EIO; + } + + printk(KERN_INFO "btrfs read error corrected: ino %lu off %llu (dev %s " + "sector %llu)\n", page->mapping->host->i_ino, start, + dev->name, sector); + + bio_put(bio); + return 0; +} + +/* + * each time an IO finishes, we do a fast check in the IO failure tree + * to see if we need to process or clean up an io_failure_record + */ +static int clean_io_failure(u64 start, struct page *page) +{ + u64 private; + u64 private_failure; + struct io_failure_record *failrec; + struct btrfs_mapping_tree *map_tree; + struct extent_state *state; + int num_copies; + int did_repair = 0; + int ret; + struct inode *inode = page->mapping->host; + + private = 0; + ret = count_range_bits(&BTRFS_I(inode)->io_failure_tree, &private, + (u64)-1, 1, EXTENT_DIRTY, 0); + if (!ret) + return 0; + + ret = get_state_private(&BTRFS_I(inode)->io_failure_tree, start, + &private_failure); + if (ret) + return 0; + + failrec = (struct io_failure_record *)(unsigned long) private_failure; + BUG_ON(!failrec->this_mirror); + + if (failrec->in_validation) { + /* there was no real error, just free the record */ + pr_debug("clean_io_failure: freeing dummy error at %llu\n", + failrec->start); + did_repair = 1; + goto out; + } + + spin_lock(&BTRFS_I(inode)->io_tree.lock); + state = find_first_extent_bit_state(&BTRFS_I(inode)->io_tree, + failrec->start, + EXTENT_LOCKED); + spin_unlock(&BTRFS_I(inode)->io_tree.lock); + + if (state && state->start == failrec->start) { + map_tree = &BTRFS_I(inode)->root->fs_info->mapping_tree; + num_copies = btrfs_num_copies(map_tree, failrec->logical, + failrec->len); + if (num_copies > 1) { + ret = repair_io_failure(map_tree, start, failrec->len, + failrec->logical, page, + failrec->failed_mirror); + did_repair = !ret; + } + } + +out: + if (!ret) + ret = free_io_failure(inode, failrec, did_repair); + + return ret; +} + +/* + * this is a generic handler for readpage errors (default + * readpage_io_failed_hook). if other copies exist, read those and write back + * good data to the failed position. does not investigate in remapping the + * failed extent elsewhere, hoping the device will be smart enough to do this as + * needed + */ + +static int bio_readpage_error(struct bio *failed_bio, struct page *page, + u64 start, u64 end, int failed_mirror, + struct extent_state *state) +{ + struct io_failure_record *failrec = NULL; + u64 private; + struct extent_map *em; + struct inode *inode = page->mapping->host; + struct extent_io_tree *failure_tree = &BTRFS_I(inode)->io_failure_tree; + struct extent_io_tree *tree = &BTRFS_I(inode)->io_tree; + struct extent_map_tree *em_tree = &BTRFS_I(inode)->extent_tree; + struct bio *bio; + int num_copies; + int ret; + int read_mode; + u64 logical; + + BUG_ON(failed_bio->bi_rw & REQ_WRITE); + + ret = get_state_private(failure_tree, start, &private); + if (ret) { + failrec = kzalloc(sizeof(*failrec), GFP_NOFS); + if (!failrec) + return -ENOMEM; + failrec->start = start; + failrec->len = end - start + 1; + failrec->this_mirror = 0; + failrec->bio_flags = 0; + failrec->in_validation = 0; + + read_lock(&em_tree->lock); + em = lookup_extent_mapping(em_tree, start, failrec->len); + if (!em) { + read_unlock(&em_tree->lock); + kfree(failrec); + return -EIO; + } + + if (em->start > start || em->start + em->len < start) { + free_extent_map(em); + em = NULL; + } + read_unlock(&em_tree->lock); + + if (!em || IS_ERR(em)) { + kfree(failrec); + return -EIO; + } + logical = start - em->start; + logical = em->block_start + logical; + if (test_bit(EXTENT_FLAG_COMPRESSED, &em->flags)) { + logical = em->block_start; + failrec->bio_flags = EXTENT_BIO_COMPRESSED; + extent_set_compress_type(&failrec->bio_flags, + em->compress_type); + } + pr_debug("bio_readpage_error: (new) logical=%llu, start=%llu, " + "len=%llu\n", logical, start, failrec->len); + failrec->logical = logical; + free_extent_map(em); + + /* set the bits in the private failure tree */ + ret = set_extent_bits(failure_tree, start, end, + EXTENT_LOCKED | EXTENT_DIRTY, GFP_NOFS); + if (ret >= 0) + ret = set_state_private(failure_tree, start, + (u64)(unsigned long)failrec); + /* set the bits in the inode's tree */ + if (ret >= 0) + ret = set_extent_bits(tree, start, end, EXTENT_DAMAGED, + GFP_NOFS); + if (ret < 0) { + kfree(failrec); + return ret; + } + } else { + failrec = (struct io_failure_record *)(unsigned long)private; + pr_debug("bio_readpage_error: (found) logical=%llu, " + "start=%llu, len=%llu, validation=%d\n", + failrec->logical, failrec->start, failrec->len, + failrec->in_validation); + /* + * when data can be on disk more than twice, add to failrec here + * (e.g. with a list for failed_mirror) to make + * clean_io_failure() clean all those errors at once. + */ + } + num_copies = btrfs_num_copies( + &BTRFS_I(inode)->root->fs_info->mapping_tree, + failrec->logical, failrec->len); + if (num_copies == 1) { + /* + * we only have a single copy of the data, so don't bother with + * all the retry and error correction code that follows. no + * matter what the error is, it is very likely to persist. + */ + pr_debug("bio_readpage_error: cannot repair, num_copies == 1. " + "state=%p, num_copies=%d, next_mirror %d, " + "failed_mirror %d\n", state, num_copies, + failrec->this_mirror, failed_mirror); + free_io_failure(inode, failrec, 0); + return -EIO; + } + + if (!state) { + spin_lock(&tree->lock); + state = find_first_extent_bit_state(tree, failrec->start, + EXTENT_LOCKED); + if (state && state->start != failrec->start) + state = NULL; + spin_unlock(&tree->lock); + } + + /* + * there are two premises: + * a) deliver good data to the caller + * b) correct the bad sectors on disk + */ + if (failed_bio->bi_vcnt > 1) { + /* + * to fulfill b), we need to know the exact failing sectors, as + * we don't want to rewrite any more than the failed ones. thus, + * we need separate read requests for the failed bio + * + * if the following BUG_ON triggers, our validation request got + * merged. we need separate requests for our algorithm to work. + */ + BUG_ON(failrec->in_validation); + failrec->in_validation = 1; + failrec->this_mirror = failed_mirror; + read_mode = READ_SYNC | REQ_FAILFAST_DEV; + } else { + /* + * we're ready to fulfill a) and b) alongside. get a good copy + * of the failed sector and if we succeed, we have setup + * everything for repair_io_failure to do the rest for us. + */ + if (failrec->in_validation) { + BUG_ON(failrec->this_mirror != failed_mirror); + failrec->in_validation = 0; + failrec->this_mirror = 0; + } + failrec->failed_mirror = failed_mirror; + failrec->this_mirror++; + if (failrec->this_mirror == failed_mirror) + failrec->this_mirror++; + read_mode = READ_SYNC; + } + + if (!state || failrec->this_mirror > num_copies) { + pr_debug("bio_readpage_error: (fail) state=%p, num_copies=%d, " + "next_mirror %d, failed_mirror %d\n", state, + num_copies, failrec->this_mirror, failed_mirror); + free_io_failure(inode, failrec, 0); + return -EIO; + } + + bio = bio_alloc(GFP_NOFS, 1); + bio->bi_private = state; + bio->bi_end_io = failed_bio->bi_end_io; + bio->bi_sector = failrec->logical >> 9; + bio->bi_bdev = BTRFS_I(inode)->root->fs_info->fs_devices->latest_bdev; + bio->bi_size = 0; + + bio_add_page(bio, page, failrec->len, start - page_offset(page)); + + pr_debug("bio_readpage_error: submitting new read[%#x] to " + "this_mirror=%d, num_copies=%d, in_validation=%d\n", read_mode, + failrec->this_mirror, num_copies, failrec->in_validation); + + tree->ops->submit_bio_hook(inode, read_mode, bio, failrec->this_mirror, + failrec->bio_flags, 0); + return 0; +} + /* lots and lots of room for performance fixes in the end_bio funcs */ /* @@ -1885,6 +2248,9 @@ static void end_bio_extent_readpage(struct bio *bio, int err) struct extent_state *cached = NULL; struct extent_state *state; + pr_debug("end_bio_extent_readpage: bi_vcnt=%d, idx=%d, err=%d, " + "mirror=%ld\n", bio->bi_vcnt, bio->bi_idx, err, + (long int)bio->bi_bdev); tree = &BTRFS_I(page->mapping->host)->io_tree; start = ((u64)page->index << PAGE_CACHE_SHIFT) + @@ -1915,11 +2281,19 @@ static void end_bio_extent_readpage(struct bio *bio, int err) state); if (ret) uptodate = 0; + else + clean_io_failure(start, page); } - if (!uptodate && tree->ops && - tree->ops->readpage_io_failed_hook) { - ret = tree->ops->readpage_io_failed_hook(bio, page, - start, end, state); + if (!uptodate) { + u64 failed_mirror; + failed_mirror = (u64)bio->bi_bdev; + if (tree->ops && tree->ops->readpage_io_failed_hook) + ret = tree->ops->readpage_io_failed_hook( + bio, page, start, end, + failed_mirror, state); + else + ret = bio_readpage_error(bio, page, start, end, + failed_mirror, NULL); if (ret == 0) { uptodate = test_bit(BIO_UPTODATE, &bio->bi_flags); @@ -1999,6 +2373,7 @@ static int submit_one_bio(int rw, struct bio *bio, int mirror_num, mirror_num, bio_flags, start); else submit_bio(rw, bio); + if (bio_flagged(bio, BIO_EOPNOTSUPP)) ret = -EOPNOTSUPP; bio_put(bio); @@ -2264,16 +2639,16 @@ out: } int extent_read_full_page(struct extent_io_tree *tree, struct page *page, - get_extent_t *get_extent) + get_extent_t *get_extent, int mirror_num) { struct bio *bio = NULL; unsigned long bio_flags = 0; int ret; - ret = __extent_read_full_page(tree, page, get_extent, &bio, 0, + ret = __extent_read_full_page(tree, page, get_extent, &bio, mirror_num, &bio_flags); if (bio) - ret = submit_one_bio(READ, bio, 0, bio_flags); + ret = submit_one_bio(READ, bio, mirror_num, bio_flags); return ret; } @@ -3127,7 +3502,7 @@ out: return ret; } -static inline struct page *extent_buffer_page(struct extent_buffer *eb, +inline struct page *extent_buffer_page(struct extent_buffer *eb, unsigned long i) { struct page *p; @@ -3152,7 +3527,7 @@ static inline struct page *extent_buffer_page(struct extent_buffer *eb, return p; } -static inline unsigned long num_extent_pages(u64 start, u64 len) +inline unsigned long num_extent_pages(u64 start, u64 len) { return ((start + len + PAGE_CACHE_SIZE - 1) >> PAGE_CACHE_SHIFT) - (start >> PAGE_CACHE_SHIFT); diff --git a/fs/btrfs/extent_io.h b/fs/btrfs/extent_io.h index 697570eed9e8..feb9be0e23bc 100644 --- a/fs/btrfs/extent_io.h +++ b/fs/btrfs/extent_io.h @@ -18,6 +18,7 @@ #define EXTENT_DO_ACCOUNTING (1 << 11) #define EXTENT_FIRST_DELALLOC (1 << 12) #define EXTENT_NEED_WAIT (1 << 13) +#define EXTENT_DAMAGED (1 << 14) #define EXTENT_IOBITS (EXTENT_LOCKED | EXTENT_WRITEBACK) #define EXTENT_CTLBITS (EXTENT_DO_ACCOUNTING | EXTENT_FIRST_DELALLOC) @@ -69,7 +70,7 @@ struct extent_io_ops { unsigned long bio_flags); int (*readpage_io_hook)(struct page *page, u64 start, u64 end); int (*readpage_io_failed_hook)(struct bio *bio, struct page *page, - u64 start, u64 end, + u64 start, u64 end, u64 failed_mirror, struct extent_state *state); int (*writepage_io_failed_hook)(struct bio *bio, struct page *page, u64 start, u64 end, @@ -188,7 +189,7 @@ int unlock_extent_cached(struct extent_io_tree *tree, u64 start, u64 end, int try_lock_extent(struct extent_io_tree *tree, u64 start, u64 end, gfp_t mask); int extent_read_full_page(struct extent_io_tree *tree, struct page *page, - get_extent_t *get_extent); + get_extent_t *get_extent, int mirror_num); int __init extent_io_init(void); void extent_io_exit(void); @@ -259,6 +260,8 @@ void free_extent_buffer(struct extent_buffer *eb); int read_extent_buffer_pages(struct extent_io_tree *tree, struct extent_buffer *eb, u64 start, int wait, get_extent_t *get_extent, int mirror_num); +unsigned long num_extent_pages(u64 start, u64 len); +struct page *extent_buffer_page(struct extent_buffer *eb, unsigned long i); static inline void extent_buffer_get(struct extent_buffer *eb) { @@ -308,4 +311,10 @@ int extent_clear_unlock_delalloc(struct inode *inode, struct bio * btrfs_bio_alloc(struct block_device *bdev, u64 first_sector, int nr_vecs, gfp_t gfp_flags); + +struct btrfs_mapping_tree; + +int repair_io_failure(struct btrfs_mapping_tree *map_tree, u64 start, + u64 length, u64 logical, struct page *page, + int mirror_num); #endif diff --git a/fs/btrfs/inode.c b/fs/btrfs/inode.c index b6b612e14ed7..9d0eaa57d4ee 100644 --- a/fs/btrfs/inode.c +++ b/fs/btrfs/inode.c @@ -45,10 +45,10 @@ #include "btrfs_inode.h" #include "ioctl.h" #include "print-tree.h" -#include "volumes.h" #include "ordered-data.h" #include "xattr.h" #include "tree-log.h" +#include "volumes.h" #include "compression.h" #include "locking.h" #include "free-space-cache.h" @@ -1822,154 +1822,10 @@ static int btrfs_writepage_end_io_hook(struct page *page, u64 start, u64 end, return btrfs_finish_ordered_io(page->mapping->host, start, end); } -/* - * When IO fails, either with EIO or csum verification fails, we - * try other mirrors that might have a good copy of the data. This - * io_failure_record is used to record state as we go through all the - * mirrors. If another mirror has good data, the page is set up to date - * and things continue. If a good mirror can't be found, the original - * bio end_io callback is called to indicate things have failed. - */ -struct io_failure_record { - struct page *page; - u64 start; - u64 len; - u64 logical; - unsigned long bio_flags; - int last_mirror; -}; - -static int btrfs_io_failed_hook(struct bio *failed_bio, - struct page *page, u64 start, u64 end, - struct extent_state *state) -{ - struct io_failure_record *failrec = NULL; - u64 private; - struct extent_map *em; - struct inode *inode = page->mapping->host; - struct extent_io_tree *failure_tree = &BTRFS_I(inode)->io_failure_tree; - struct extent_map_tree *em_tree = &BTRFS_I(inode)->extent_tree; - struct bio *bio; - int num_copies; - int ret; - int rw; - u64 logical; - - ret = get_state_private(failure_tree, start, &private); - if (ret) { - failrec = kmalloc(sizeof(*failrec), GFP_NOFS); - if (!failrec) - return -ENOMEM; - failrec->start = start; - failrec->len = end - start + 1; - failrec->last_mirror = 0; - failrec->bio_flags = 0; - - read_lock(&em_tree->lock); - em = lookup_extent_mapping(em_tree, start, failrec->len); - if (em->start > start || em->start + em->len < start) { - free_extent_map(em); - em = NULL; - } - read_unlock(&em_tree->lock); - - if (IS_ERR_OR_NULL(em)) { - kfree(failrec); - return -EIO; - } - logical = start - em->start; - logical = em->block_start + logical; - if (test_bit(EXTENT_FLAG_COMPRESSED, &em->flags)) { - logical = em->block_start; - failrec->bio_flags = EXTENT_BIO_COMPRESSED; - extent_set_compress_type(&failrec->bio_flags, - em->compress_type); - } - failrec->logical = logical; - free_extent_map(em); - set_extent_bits(failure_tree, start, end, EXTENT_LOCKED | - EXTENT_DIRTY, GFP_NOFS); - set_state_private(failure_tree, start, - (u64)(unsigned long)failrec); - } else { - failrec = (struct io_failure_record *)(unsigned long)private; - } - num_copies = btrfs_num_copies( - &BTRFS_I(inode)->root->fs_info->mapping_tree, - failrec->logical, failrec->len); - failrec->last_mirror++; - if (!state) { - spin_lock(&BTRFS_I(inode)->io_tree.lock); - state = find_first_extent_bit_state(&BTRFS_I(inode)->io_tree, - failrec->start, - EXTENT_LOCKED); - if (state && state->start != failrec->start) - state = NULL; - spin_unlock(&BTRFS_I(inode)->io_tree.lock); - } - if (!state || failrec->last_mirror > num_copies) { - set_state_private(failure_tree, failrec->start, 0); - clear_extent_bits(failure_tree, failrec->start, - failrec->start + failrec->len - 1, - EXTENT_LOCKED | EXTENT_DIRTY, GFP_NOFS); - kfree(failrec); - return -EIO; - } - bio = bio_alloc(GFP_NOFS, 1); - bio->bi_private = state; - bio->bi_end_io = failed_bio->bi_end_io; - bio->bi_sector = failrec->logical >> 9; - bio->bi_bdev = failed_bio->bi_bdev; - bio->bi_size = 0; - - bio_add_page(bio, page, failrec->len, start - page_offset(page)); - if (failed_bio->bi_rw & REQ_WRITE) - rw = WRITE; - else - rw = READ; - - ret = BTRFS_I(inode)->io_tree.ops->submit_bio_hook(inode, rw, bio, - failrec->last_mirror, - failrec->bio_flags, 0); - return ret; -} - -/* - * each time an IO finishes, we do a fast check in the IO failure tree - * to see if we need to process or clean up an io_failure_record - */ -static int btrfs_clean_io_failures(struct inode *inode, u64 start) -{ - u64 private; - u64 private_failure; - struct io_failure_record *failure; - int ret; - - private = 0; - if (count_range_bits(&BTRFS_I(inode)->io_failure_tree, &private, - (u64)-1, 1, EXTENT_DIRTY, 0)) { - ret = get_state_private(&BTRFS_I(inode)->io_failure_tree, - start, &private_failure); - if (ret == 0) { - failure = (struct io_failure_record *)(unsigned long) - private_failure; - set_state_private(&BTRFS_I(inode)->io_failure_tree, - failure->start, 0); - clear_extent_bits(&BTRFS_I(inode)->io_failure_tree, - failure->start, - failure->start + failure->len - 1, - EXTENT_DIRTY | EXTENT_LOCKED, - GFP_NOFS); - kfree(failure); - } - } - return 0; -} - /* * when reads are done, we need to check csums to verify the data is correct - * if there's a match, we allow the bio to finish. If not, we go through - * the io_failure_record routines to find good copies + * if there's a match, we allow the bio to finish. If not, the code in + * extent_io.c will try to find good copies for us. */ static int btrfs_readpage_end_io_hook(struct page *page, u64 start, u64 end, struct extent_state *state) @@ -2015,10 +1871,6 @@ static int btrfs_readpage_end_io_hook(struct page *page, u64 start, u64 end, kunmap_atomic(kaddr, KM_USER0); good: - /* if the io failure tree for this inode is non-empty, - * check to see if we've recovered from a failed IO - */ - btrfs_clean_io_failures(inode, start); return 0; zeroit: @@ -6273,7 +6125,7 @@ int btrfs_readpage(struct file *file, struct page *page) { struct extent_io_tree *tree; tree = &BTRFS_I(page->mapping->host)->io_tree; - return extent_read_full_page(tree, page, btrfs_get_extent); + return extent_read_full_page(tree, page, btrfs_get_extent, 0); } static int btrfs_writepage(struct page *page, struct writeback_control *wbc) @@ -7406,7 +7258,6 @@ static struct extent_io_ops btrfs_extent_io_ops = { .readpage_end_io_hook = btrfs_readpage_end_io_hook, .writepage_end_io_hook = btrfs_writepage_end_io_hook, .writepage_start_hook = btrfs_writepage_start_hook, - .readpage_io_failed_hook = btrfs_io_failed_hook, .set_bit_hook = btrfs_set_bit_hook, .clear_bit_hook = btrfs_clear_bit_hook, .merge_extent_hook = btrfs_merge_extent_hook, diff --git a/fs/btrfs/ioctl.c b/fs/btrfs/ioctl.c index 8f6e14279409..cc9893990341 100644 --- a/fs/btrfs/ioctl.c +++ b/fs/btrfs/ioctl.c @@ -51,6 +51,7 @@ #include "volumes.h" #include "locking.h" #include "inode-map.h" +#include "backref.h" /* Mask out flags that are inappropriate for the given type of inode. */ static inline __u32 btrfs_mask_flags(umode_t mode, __u32 flags) @@ -2890,6 +2891,144 @@ static long btrfs_ioctl_scrub_progress(struct btrfs_root *root, return ret; } +static long btrfs_ioctl_ino_to_path(struct btrfs_root *root, void __user *arg) +{ + int ret = 0; + int i; + unsigned long rel_ptr; + int size; + struct btrfs_ioctl_ino_path_args *ipa = NULL; + struct inode_fs_paths *ipath = NULL; + struct btrfs_path *path; + + if (!capable(CAP_SYS_ADMIN)) + return -EPERM; + + path = btrfs_alloc_path(); + if (!path) { + ret = -ENOMEM; + goto out; + } + + ipa = memdup_user(arg, sizeof(*ipa)); + if (IS_ERR(ipa)) { + ret = PTR_ERR(ipa); + ipa = NULL; + goto out; + } + + size = min_t(u32, ipa->size, 4096); + ipath = init_ipath(size, root, path); + if (IS_ERR(ipath)) { + ret = PTR_ERR(ipath); + ipath = NULL; + goto out; + } + + ret = paths_from_inode(ipa->inum, ipath); + if (ret < 0) + goto out; + + for (i = 0; i < ipath->fspath->elem_cnt; ++i) { + rel_ptr = ipath->fspath->str[i] - (char *)ipath->fspath->str; + ipath->fspath->str[i] = (void *)rel_ptr; + } + + ret = copy_to_user(ipa->fspath, ipath->fspath, size); + if (ret) { + ret = -EFAULT; + goto out; + } + +out: + btrfs_free_path(path); + free_ipath(ipath); + kfree(ipa); + + return ret; +} + +static int build_ino_list(u64 inum, u64 offset, u64 root, void *ctx) +{ + struct btrfs_data_container *inodes = ctx; + const size_t c = 3 * sizeof(u64); + + if (inodes->bytes_left >= c) { + inodes->bytes_left -= c; + inodes->val[inodes->elem_cnt] = inum; + inodes->val[inodes->elem_cnt + 1] = offset; + inodes->val[inodes->elem_cnt + 2] = root; + inodes->elem_cnt += 3; + } else { + inodes->bytes_missing += c - inodes->bytes_left; + inodes->bytes_left = 0; + inodes->elem_missed += 3; + } + + return 0; +} + +static long btrfs_ioctl_logical_to_ino(struct btrfs_root *root, + void __user *arg) +{ + int ret = 0; + int size; + u64 extent_offset; + struct btrfs_ioctl_logical_ino_args *loi; + struct btrfs_data_container *inodes = NULL; + struct btrfs_path *path = NULL; + struct btrfs_key key; + + if (!capable(CAP_SYS_ADMIN)) + return -EPERM; + + loi = memdup_user(arg, sizeof(*loi)); + if (IS_ERR(loi)) { + ret = PTR_ERR(loi); + loi = NULL; + goto out; + } + + path = btrfs_alloc_path(); + if (!path) { + ret = -ENOMEM; + goto out; + } + + size = min_t(u32, loi->size, 4096); + inodes = init_data_container(size); + if (IS_ERR(inodes)) { + ret = PTR_ERR(inodes); + inodes = NULL; + goto out; + } + + ret = extent_from_logical(root->fs_info, loi->logical, path, &key); + + if (ret & BTRFS_EXTENT_FLAG_TREE_BLOCK) + ret = -ENOENT; + if (ret < 0) + goto out; + + extent_offset = loi->logical - key.objectid; + ret = iterate_extent_inodes(root->fs_info, path, key.objectid, + extent_offset, build_ino_list, inodes); + + if (ret < 0) + goto out; + + ret = copy_to_user(loi->inodes, inodes, size); + if (ret) + ret = -EFAULT; + +out: + btrfs_free_path(path); + kfree(inodes); + kfree(loi); + + return ret; +} + long btrfs_ioctl(struct file *file, unsigned int cmd, unsigned long arg) { @@ -2947,6 +3086,10 @@ long btrfs_ioctl(struct file *file, unsigned int return btrfs_ioctl_tree_search(file, argp); case BTRFS_IOC_INO_LOOKUP: return btrfs_ioctl_ino_lookup(file, argp); + case BTRFS_IOC_INO_PATHS: + return btrfs_ioctl_ino_to_path(root, argp); + case BTRFS_IOC_LOGICAL_INO: + return btrfs_ioctl_logical_to_ino(root, argp); case BTRFS_IOC_SPACE_INFO: return btrfs_ioctl_space_info(root, argp); case BTRFS_IOC_SYNC: diff --git a/fs/btrfs/ioctl.h b/fs/btrfs/ioctl.h index ad1ea789fcb4..2da30d4950e6 100644 --- a/fs/btrfs/ioctl.h +++ b/fs/btrfs/ioctl.h @@ -193,6 +193,31 @@ struct btrfs_ioctl_space_args { struct btrfs_ioctl_space_info spaces[0]; }; +struct btrfs_data_container { + __u32 bytes_left; /* out -- bytes not needed to deliver output */ + __u32 bytes_missing; /* out -- additional bytes needed for result */ + __u32 elem_cnt; /* out */ + __u32 elem_missed; /* out */ + union { + char *str[0]; /* out */ + __u64 val[0]; /* out */ + }; +}; + +struct btrfs_ioctl_ino_path_args { + __u64 inum; /* in */ + __u32 size; /* in */ + __u64 reserved[4]; + struct btrfs_data_container *fspath; /* out */ +}; + +struct btrfs_ioctl_logical_ino_args { + __u64 logical; /* in */ + __u32 size; /* in */ + __u64 reserved[4]; + struct btrfs_data_container *inodes; /* out */ +}; + #define BTRFS_IOC_SNAP_CREATE _IOW(BTRFS_IOCTL_MAGIC, 1, \ struct btrfs_ioctl_vol_args) #define BTRFS_IOC_DEFRAG _IOW(BTRFS_IOCTL_MAGIC, 2, \ @@ -248,4 +273,9 @@ struct btrfs_ioctl_space_args { struct btrfs_ioctl_dev_info_args) #define BTRFS_IOC_FS_INFO _IOR(BTRFS_IOCTL_MAGIC, 31, \ struct btrfs_ioctl_fs_info_args) +#define BTRFS_IOC_INO_PATHS _IOWR(BTRFS_IOCTL_MAGIC, 35, \ + struct btrfs_ioctl_ino_path_args) +#define BTRFS_IOC_LOGICAL_INO _IOWR(BTRFS_IOCTL_MAGIC, 36, \ + struct btrfs_ioctl_ino_path_args) + #endif diff --git a/fs/btrfs/reada.c b/fs/btrfs/reada.c index 2b701d082227..cd857119ba8a 100644 --- a/fs/btrfs/reada.c +++ b/fs/btrfs/reada.c @@ -247,7 +247,7 @@ int btree_readahead_hook(struct btrfs_root *root, struct extent_buffer *eb, static struct reada_zone *reada_find_zone(struct btrfs_fs_info *fs_info, struct btrfs_device *dev, u64 logical, - struct btrfs_multi_bio *multi) + struct btrfs_bio *multi) { int ret; int looped = 0; @@ -327,7 +327,7 @@ static struct reada_extent *reada_find_extent(struct btrfs_root *root, struct reada_extent *re = NULL; struct btrfs_fs_info *fs_info = root->fs_info; struct btrfs_mapping_tree *map_tree = &fs_info->mapping_tree; - struct btrfs_multi_bio *multi = NULL; + struct btrfs_bio *multi = NULL; struct btrfs_device *dev; u32 blocksize; u64 length; diff --git a/fs/btrfs/scrub.c b/fs/btrfs/scrub.c index 5bc4ec827b3d..94cd3a19e9c8 100644 --- a/fs/btrfs/scrub.c +++ b/fs/btrfs/scrub.c @@ -17,10 +17,14 @@ */ #include +#include #include "ctree.h" #include "volumes.h" #include "disk-io.h" #include "ordered-data.h" +#include "transaction.h" +#include "backref.h" +#include "extent_io.h" /* * This is only the first step towards a full-features scrub. It reads all @@ -60,7 +64,7 @@ static void scrub_fixup(struct scrub_bio *sbio, int ix); struct scrub_page { u64 flags; /* extent flags */ u64 generation; - u64 mirror_num; + int mirror_num; int have_csum; u8 csum[BTRFS_CSUM_SIZE]; }; @@ -84,6 +88,7 @@ struct scrub_dev { int first_free; int curr; atomic_t in_flight; + atomic_t fixup_cnt; spinlock_t list_lock; wait_queue_head_t list_wait; u16 csum_size; @@ -97,6 +102,27 @@ struct scrub_dev { spinlock_t stat_lock; }; +struct scrub_fixup_nodatasum { + struct scrub_dev *sdev; + u64 logical; + struct btrfs_root *root; + struct btrfs_work work; + int mirror_num; +}; + +struct scrub_warning { + struct btrfs_path *path; + u64 extent_item_size; + char *scratch_buf; + char *msg_buf; + const char *errstr; + sector_t sector; + u64 logical; + struct btrfs_device *dev; + int msg_bufsize; + int scratch_bufsize; +}; + static void scrub_free_csums(struct scrub_dev *sdev) { while (!list_empty(&sdev->csum_list)) { @@ -172,12 +198,13 @@ struct scrub_dev *scrub_setup_dev(struct btrfs_device *dev) if (i != SCRUB_BIOS_PER_DEV-1) sdev->bios[i]->next_free = i + 1; - else + else sdev->bios[i]->next_free = -1; } sdev->first_free = 0; sdev->curr = -1; atomic_set(&sdev->in_flight, 0); + atomic_set(&sdev->fixup_cnt, 0); atomic_set(&sdev->cancel_req, 0); sdev->csum_size = btrfs_super_csum_size(fs_info->super_copy); INIT_LIST_HEAD(&sdev->csum_list); @@ -192,24 +219,361 @@ nomem: return ERR_PTR(-ENOMEM); } +static int scrub_print_warning_inode(u64 inum, u64 offset, u64 root, void *ctx) +{ + u64 isize; + u32 nlink; + int ret; + int i; + struct extent_buffer *eb; + struct btrfs_inode_item *inode_item; + struct scrub_warning *swarn = ctx; + struct btrfs_fs_info *fs_info = swarn->dev->dev_root->fs_info; + struct inode_fs_paths *ipath = NULL; + struct btrfs_root *local_root; + struct btrfs_key root_key; + + root_key.objectid = root; + root_key.type = BTRFS_ROOT_ITEM_KEY; + root_key.offset = (u64)-1; + local_root = btrfs_read_fs_root_no_name(fs_info, &root_key); + if (IS_ERR(local_root)) { + ret = PTR_ERR(local_root); + goto err; + } + + ret = inode_item_info(inum, 0, local_root, swarn->path); + if (ret) { + btrfs_release_path(swarn->path); + goto err; + } + + eb = swarn->path->nodes[0]; + inode_item = btrfs_item_ptr(eb, swarn->path->slots[0], + struct btrfs_inode_item); + isize = btrfs_inode_size(eb, inode_item); + nlink = btrfs_inode_nlink(eb, inode_item); + btrfs_release_path(swarn->path); + + ipath = init_ipath(4096, local_root, swarn->path); + ret = paths_from_inode(inum, ipath); + + if (ret < 0) + goto err; + + /* + * we deliberately ignore the bit ipath might have been too small to + * hold all of the paths here + */ + for (i = 0; i < ipath->fspath->elem_cnt; ++i) + printk(KERN_WARNING "btrfs: %s at logical %llu on dev " + "%s, sector %llu, root %llu, inode %llu, offset %llu, " + "length %llu, links %u (path: %s)\n", swarn->errstr, + swarn->logical, swarn->dev->name, + (unsigned long long)swarn->sector, root, inum, offset, + min(isize - offset, (u64)PAGE_SIZE), nlink, + ipath->fspath->str[i]); + + free_ipath(ipath); + return 0; + +err: + printk(KERN_WARNING "btrfs: %s at logical %llu on dev " + "%s, sector %llu, root %llu, inode %llu, offset %llu: path " + "resolving failed with ret=%d\n", swarn->errstr, + swarn->logical, swarn->dev->name, + (unsigned long long)swarn->sector, root, inum, offset, ret); + + free_ipath(ipath); + return 0; +} + +static void scrub_print_warning(const char *errstr, struct scrub_bio *sbio, + int ix) +{ + struct btrfs_device *dev = sbio->sdev->dev; + struct btrfs_fs_info *fs_info = dev->dev_root->fs_info; + struct btrfs_path *path; + struct btrfs_key found_key; + struct extent_buffer *eb; + struct btrfs_extent_item *ei; + struct scrub_warning swarn; + u32 item_size; + int ret; + u64 ref_root; + u8 ref_level; + unsigned long ptr = 0; + const int bufsize = 4096; + u64 extent_offset; + + path = btrfs_alloc_path(); + + swarn.scratch_buf = kmalloc(bufsize, GFP_NOFS); + swarn.msg_buf = kmalloc(bufsize, GFP_NOFS); + swarn.sector = (sbio->physical + ix * PAGE_SIZE) >> 9; + swarn.logical = sbio->logical + ix * PAGE_SIZE; + swarn.errstr = errstr; + swarn.dev = dev; + swarn.msg_bufsize = bufsize; + swarn.scratch_bufsize = bufsize; + + if (!path || !swarn.scratch_buf || !swarn.msg_buf) + goto out; + + ret = extent_from_logical(fs_info, swarn.logical, path, &found_key); + if (ret < 0) + goto out; + + extent_offset = swarn.logical - found_key.objectid; + swarn.extent_item_size = found_key.offset; + + eb = path->nodes[0]; + ei = btrfs_item_ptr(eb, path->slots[0], struct btrfs_extent_item); + item_size = btrfs_item_size_nr(eb, path->slots[0]); + + if (ret & BTRFS_EXTENT_FLAG_TREE_BLOCK) { + do { + ret = tree_backref_for_extent(&ptr, eb, ei, item_size, + &ref_root, &ref_level); + printk(KERN_WARNING "%s at logical %llu on dev %s, " + "sector %llu: metadata %s (level %d) in tree " + "%llu\n", errstr, swarn.logical, dev->name, + (unsigned long long)swarn.sector, + ref_level ? "node" : "leaf", + ret < 0 ? -1 : ref_level, + ret < 0 ? -1 : ref_root); + } while (ret != 1); + } else { + swarn.path = path; + iterate_extent_inodes(fs_info, path, found_key.objectid, + extent_offset, + scrub_print_warning_inode, &swarn); + } + +out: + btrfs_free_path(path); + kfree(swarn.scratch_buf); + kfree(swarn.msg_buf); +} + +static int scrub_fixup_readpage(u64 inum, u64 offset, u64 root, void *ctx) +{ + struct page *page = NULL; + unsigned long index; + struct scrub_fixup_nodatasum *fixup = ctx; + int ret; + int corrected = 0; + struct btrfs_key key; + struct inode *inode = NULL; + u64 end = offset + PAGE_SIZE - 1; + struct btrfs_root *local_root; + + key.objectid = root; + key.type = BTRFS_ROOT_ITEM_KEY; + key.offset = (u64)-1; + local_root = btrfs_read_fs_root_no_name(fixup->root->fs_info, &key); + if (IS_ERR(local_root)) + return PTR_ERR(local_root); + + key.type = BTRFS_INODE_ITEM_KEY; + key.objectid = inum; + key.offset = 0; + inode = btrfs_iget(fixup->root->fs_info->sb, &key, local_root, NULL); + if (IS_ERR(inode)) + return PTR_ERR(inode); + + index = offset >> PAGE_CACHE_SHIFT; + + page = find_or_create_page(inode->i_mapping, index, GFP_NOFS); + if (!page) { + ret = -ENOMEM; + goto out; + } + + if (PageUptodate(page)) { + struct btrfs_mapping_tree *map_tree; + if (PageDirty(page)) { + /* + * we need to write the data to the defect sector. the + * data that was in that sector is not in memory, + * because the page was modified. we must not write the + * modified page to that sector. + * + * TODO: what could be done here: wait for the delalloc + * runner to write out that page (might involve + * COW) and see whether the sector is still + * referenced afterwards. + * + * For the meantime, we'll treat this error + * incorrectable, although there is a chance that a + * later scrub will find the bad sector again and that + * there's no dirty page in memory, then. + */ + ret = -EIO; + goto out; + } + map_tree = &BTRFS_I(inode)->root->fs_info->mapping_tree; + ret = repair_io_failure(map_tree, offset, PAGE_SIZE, + fixup->logical, page, + fixup->mirror_num); + unlock_page(page); + corrected = !ret; + } else { + /* + * we need to get good data first. the general readpage path + * will call repair_io_failure for us, we just have to make + * sure we read the bad mirror. + */ + ret = set_extent_bits(&BTRFS_I(inode)->io_tree, offset, end, + EXTENT_DAMAGED, GFP_NOFS); + if (ret) { + /* set_extent_bits should give proper error */ + WARN_ON(ret > 0); + if (ret > 0) + ret = -EFAULT; + goto out; + } + + ret = extent_read_full_page(&BTRFS_I(inode)->io_tree, page, + btrfs_get_extent, + fixup->mirror_num); + wait_on_page_locked(page); + + corrected = !test_range_bit(&BTRFS_I(inode)->io_tree, offset, + end, EXTENT_DAMAGED, 0, NULL); + if (!corrected) + clear_extent_bits(&BTRFS_I(inode)->io_tree, offset, end, + EXTENT_DAMAGED, GFP_NOFS); + } + +out: + if (page) + put_page(page); + if (inode) + iput(inode); + + if (ret < 0) + return ret; + + if (ret == 0 && corrected) { + /* + * we only need to call readpage for one of the inodes belonging + * to this extent. so make iterate_extent_inodes stop + */ + return 1; + } + + return -EIO; +} + +static void scrub_fixup_nodatasum(struct btrfs_work *work) +{ + int ret; + struct scrub_fixup_nodatasum *fixup; + struct scrub_dev *sdev; + struct btrfs_trans_handle *trans = NULL; + struct btrfs_fs_info *fs_info; + struct btrfs_path *path; + int uncorrectable = 0; + + fixup = container_of(work, struct scrub_fixup_nodatasum, work); + sdev = fixup->sdev; + fs_info = fixup->root->fs_info; + + path = btrfs_alloc_path(); + if (!path) { + spin_lock(&sdev->stat_lock); + ++sdev->stat.malloc_errors; + spin_unlock(&sdev->stat_lock); + uncorrectable = 1; + goto out; + } + + trans = btrfs_join_transaction(fixup->root); + if (IS_ERR(trans)) { + uncorrectable = 1; + goto out; + } + + /* + * the idea is to trigger a regular read through the standard path. we + * read a page from the (failed) logical address by specifying the + * corresponding copynum of the failed sector. thus, that readpage is + * expected to fail. + * that is the point where on-the-fly error correction will kick in + * (once it's finished) and rewrite the failed sector if a good copy + * can be found. + */ + ret = iterate_inodes_from_logical(fixup->logical, fixup->root->fs_info, + path, scrub_fixup_readpage, + fixup); + if (ret < 0) { + uncorrectable = 1; + goto out; + } + WARN_ON(ret != 1); + + spin_lock(&sdev->stat_lock); + ++sdev->stat.corrected_errors; + spin_unlock(&sdev->stat_lock); + +out: + if (trans && !IS_ERR(trans)) + btrfs_end_transaction(trans, fixup->root); + if (uncorrectable) { + spin_lock(&sdev->stat_lock); + ++sdev->stat.uncorrectable_errors; + spin_unlock(&sdev->stat_lock); + printk_ratelimited(KERN_ERR "btrfs: unable to fixup " + "(nodatasum) error at logical %llu\n", + fixup->logical); + } + + btrfs_free_path(path); + kfree(fixup); + + /* see caller why we're pretending to be paused in the scrub counters */ + mutex_lock(&fs_info->scrub_lock); + atomic_dec(&fs_info->scrubs_running); + atomic_dec(&fs_info->scrubs_paused); + mutex_unlock(&fs_info->scrub_lock); + atomic_dec(&sdev->fixup_cnt); + wake_up(&fs_info->scrub_pause_wait); + wake_up(&sdev->list_wait); +} + /* * scrub_recheck_error gets called when either verification of the page * failed or the bio failed to read, e.g. with EIO. In the latter case, * recheck_error gets called for every page in the bio, even though only * one may be bad */ -static void scrub_recheck_error(struct scrub_bio *sbio, int ix) +static int scrub_recheck_error(struct scrub_bio *sbio, int ix) { + struct scrub_dev *sdev = sbio->sdev; + u64 sector = (sbio->physical + ix * PAGE_SIZE) >> 9; + static DEFINE_RATELIMIT_STATE(_rs, DEFAULT_RATELIMIT_INTERVAL, + DEFAULT_RATELIMIT_BURST); + if (sbio->err) { - if (scrub_fixup_io(READ, sbio->sdev->dev->bdev, - (sbio->physical + ix * PAGE_SIZE) >> 9, + if (scrub_fixup_io(READ, sbio->sdev->dev->bdev, sector, sbio->bio->bi_io_vec[ix].bv_page) == 0) { if (scrub_fixup_check(sbio, ix) == 0) - return; + return 0; } + if (__ratelimit(&_rs)) + scrub_print_warning("i/o error", sbio, ix); + } else { + if (__ratelimit(&_rs)) + scrub_print_warning("checksum error", sbio, ix); } + spin_lock(&sdev->stat_lock); + ++sdev->stat.read_errors; + spin_unlock(&sdev->stat_lock); + scrub_fixup(sbio, ix); + return 1; } static int scrub_fixup_check(struct scrub_bio *sbio, int ix) @@ -247,7 +611,8 @@ static void scrub_fixup(struct scrub_bio *sbio, int ix) struct scrub_dev *sdev = sbio->sdev; struct btrfs_fs_info *fs_info = sdev->dev->dev_root->fs_info; struct btrfs_mapping_tree *map_tree = &fs_info->mapping_tree; - struct btrfs_multi_bio *multi = NULL; + struct btrfs_bio *bbio = NULL; + struct scrub_fixup_nodatasum *fixup; u64 logical = sbio->logical + ix * PAGE_SIZE; u64 length; int i; @@ -256,18 +621,36 @@ static void scrub_fixup(struct scrub_bio *sbio, int ix) if ((sbio->spag[ix].flags & BTRFS_EXTENT_FLAG_DATA) && (sbio->spag[ix].have_csum == 0)) { + fixup = kzalloc(sizeof(*fixup), GFP_NOFS); + if (!fixup) + goto uncorrectable; + fixup->sdev = sdev; + fixup->logical = logical; + fixup->root = fs_info->extent_root; + fixup->mirror_num = sbio->spag[ix].mirror_num; /* - * nodatasum, don't try to fix anything - * FIXME: we can do better, open the inode and trigger a - * writeback + * increment scrubs_running to prevent cancel requests from + * completing as long as a fixup worker is running. we must also + * increment scrubs_paused to prevent deadlocking on pause + * requests used for transactions commits (as the worker uses a + * transaction context). it is safe to regard the fixup worker + * as paused for all matters practical. effectively, we only + * avoid cancellation requests from completing. */ - goto uncorrectable; + mutex_lock(&fs_info->scrub_lock); + atomic_inc(&fs_info->scrubs_running); + atomic_inc(&fs_info->scrubs_paused); + mutex_unlock(&fs_info->scrub_lock); + atomic_inc(&sdev->fixup_cnt); + fixup->work.func = scrub_fixup_nodatasum; + btrfs_queue_worker(&fs_info->scrub_workers, &fixup->work); + return; } length = PAGE_SIZE; ret = btrfs_map_block(map_tree, REQ_WRITE, logical, &length, - &multi, 0); - if (ret || !multi || length < PAGE_SIZE) { + &bbio, 0); + if (ret || !bbio || length < PAGE_SIZE) { printk(KERN_ERR "scrub_fixup: btrfs_map_block failed us for %llu\n", (unsigned long long)logical); @@ -275,19 +658,19 @@ static void scrub_fixup(struct scrub_bio *sbio, int ix) return; } - if (multi->num_stripes == 1) + if (bbio->num_stripes == 1) /* there aren't any replicas */ goto uncorrectable; /* * first find a good copy */ - for (i = 0; i < multi->num_stripes; ++i) { - if (i == sbio->spag[ix].mirror_num) + for (i = 0; i < bbio->num_stripes; ++i) { + if (i + 1 == sbio->spag[ix].mirror_num) continue; - if (scrub_fixup_io(READ, multi->stripes[i].dev->bdev, - multi->stripes[i].physical >> 9, + if (scrub_fixup_io(READ, bbio->stripes[i].dev->bdev, + bbio->stripes[i].physical >> 9, sbio->bio->bi_io_vec[ix].bv_page)) { /* I/O-error, this is not a good copy */ continue; @@ -296,7 +679,7 @@ static void scrub_fixup(struct scrub_bio *sbio, int ix) if (scrub_fixup_check(sbio, ix) == 0) break; } - if (i == multi->num_stripes) + if (i == bbio->num_stripes) goto uncorrectable; if (!sdev->readonly) { @@ -311,25 +694,23 @@ static void scrub_fixup(struct scrub_bio *sbio, int ix) } } - kfree(multi); + kfree(bbio); spin_lock(&sdev->stat_lock); ++sdev->stat.corrected_errors; spin_unlock(&sdev->stat_lock); - if (printk_ratelimit()) - printk(KERN_ERR "btrfs: fixed up at %llu\n", - (unsigned long long)logical); + printk_ratelimited(KERN_ERR "btrfs: fixed up error at logical %llu\n", + (unsigned long long)logical); return; uncorrectable: - kfree(multi); + kfree(bbio); spin_lock(&sdev->stat_lock); ++sdev->stat.uncorrectable_errors; spin_unlock(&sdev->stat_lock); - if (printk_ratelimit()) - printk(KERN_ERR "btrfs: unable to fixup at %llu\n", - (unsigned long long)logical); + printk_ratelimited(KERN_ERR "btrfs: unable to fixup (regular) error at " + "logical %llu\n", (unsigned long long)logical); } static int scrub_fixup_io(int rw, struct block_device *bdev, sector_t sector, @@ -379,8 +760,14 @@ static void scrub_checksum(struct btrfs_work *work) int ret; if (sbio->err) { + ret = 0; for (i = 0; i < sbio->count; ++i) - scrub_recheck_error(sbio, i); + ret |= scrub_recheck_error(sbio, i); + if (!ret) { + spin_lock(&sdev->stat_lock); + ++sdev->stat.unverified_errors; + spin_unlock(&sdev->stat_lock); + } sbio->bio->bi_flags &= ~(BIO_POOL_MASK - 1); sbio->bio->bi_flags |= 1 << BIO_UPTODATE; @@ -393,10 +780,6 @@ static void scrub_checksum(struct btrfs_work *work) bi->bv_offset = 0; bi->bv_len = PAGE_SIZE; } - - spin_lock(&sdev->stat_lock); - ++sdev->stat.read_errors; - spin_unlock(&sdev->stat_lock); goto out; } for (i = 0; i < sbio->count; ++i) { @@ -417,8 +800,14 @@ static void scrub_checksum(struct btrfs_work *work) WARN_ON(1); } kunmap_atomic(buffer, KM_USER0); - if (ret) - scrub_recheck_error(sbio, i); + if (ret) { + ret = scrub_recheck_error(sbio, i); + if (!ret) { + spin_lock(&sdev->stat_lock); + ++sdev->stat.unverified_errors; + spin_unlock(&sdev->stat_lock); + } + } } out: @@ -601,7 +990,7 @@ nomem: } static int scrub_page(struct scrub_dev *sdev, u64 logical, u64 len, - u64 physical, u64 flags, u64 gen, u64 mirror_num, + u64 physical, u64 flags, u64 gen, int mirror_num, u8 *csum, int force) { struct scrub_bio *sbio; @@ -698,7 +1087,7 @@ static int scrub_find_csum(struct scrub_dev *sdev, u64 logical, u64 len, /* scrub extent tries to collect up to 64 kB for each bio */ static int scrub_extent(struct scrub_dev *sdev, u64 logical, u64 len, - u64 physical, u64 flags, u64 gen, u64 mirror_num) + u64 physical, u64 flags, u64 gen, int mirror_num) { int ret; u8 csum[BTRFS_CSUM_SIZE]; @@ -743,7 +1132,7 @@ static noinline_for_stack int scrub_stripe(struct scrub_dev *sdev, u64 physical; u64 logical; u64 generation; - u64 mirror_num; + int mirror_num; struct reada_control *reada1; struct reada_control *reada2; struct btrfs_key key_start; @@ -758,21 +1147,21 @@ static noinline_for_stack int scrub_stripe(struct scrub_dev *sdev, if (map->type & BTRFS_BLOCK_GROUP_RAID0) { offset = map->stripe_len * num; increment = map->stripe_len * map->num_stripes; - mirror_num = 0; + mirror_num = 1; } else if (map->type & BTRFS_BLOCK_GROUP_RAID10) { int factor = map->num_stripes / map->sub_stripes; offset = map->stripe_len * (num / map->sub_stripes); increment = map->stripe_len * factor; - mirror_num = num % map->sub_stripes; + mirror_num = num % map->sub_stripes + 1; } else if (map->type & BTRFS_BLOCK_GROUP_RAID1) { increment = map->stripe_len; - mirror_num = num % map->num_stripes; + mirror_num = num % map->num_stripes + 1; } else if (map->type & BTRFS_BLOCK_GROUP_DUP) { increment = map->stripe_len; - mirror_num = num % map->num_stripes; + mirror_num = num % map->num_stripes + 1; } else { increment = map->stripe_len; - mirror_num = 0; + mirror_num = 1; } path = btrfs_alloc_path(); @@ -1241,10 +1630,11 @@ int btrfs_scrub_dev(struct btrfs_root *root, u64 devid, u64 start, u64 end, ret = scrub_enumerate_chunks(sdev, start, end); wait_event(sdev->list_wait, atomic_read(&sdev->in_flight) == 0); - atomic_dec(&fs_info->scrubs_running); wake_up(&fs_info->scrub_pause_wait); + wait_event(sdev->list_wait, atomic_read(&sdev->fixup_cnt) == 0); + if (progress) memcpy(progress, &sdev->stat, sizeof(*progress)); diff --git a/fs/btrfs/volumes.c b/fs/btrfs/volumes.c index f1685a2b45c8..f8e2943101a1 100644 --- a/fs/btrfs/volumes.c +++ b/fs/btrfs/volumes.c @@ -2880,7 +2880,7 @@ static int find_live_mirror(struct map_lookup *map, int first, int num, static int __btrfs_map_block(struct btrfs_mapping_tree *map_tree, int rw, u64 logical, u64 *length, - struct btrfs_multi_bio **multi_ret, + struct btrfs_bio **bbio_ret, int mirror_num) { struct extent_map *em; @@ -2898,18 +2898,18 @@ static int __btrfs_map_block(struct btrfs_mapping_tree *map_tree, int rw, int i; int num_stripes; int max_errors = 0; - struct btrfs_multi_bio *multi = NULL; + struct btrfs_bio *bbio = NULL; - if (multi_ret && !(rw & (REQ_WRITE | REQ_DISCARD))) + if (bbio_ret && !(rw & (REQ_WRITE | REQ_DISCARD))) stripes_allocated = 1; again: - if (multi_ret) { - multi = kzalloc(btrfs_multi_bio_size(stripes_allocated), + if (bbio_ret) { + bbio = kzalloc(btrfs_bio_size(stripes_allocated), GFP_NOFS); - if (!multi) + if (!bbio) return -ENOMEM; - atomic_set(&multi->error, 0); + atomic_set(&bbio->error, 0); } read_lock(&em_tree->lock); @@ -2930,7 +2930,7 @@ again: if (mirror_num > map->num_stripes) mirror_num = 0; - /* if our multi bio struct is too small, back off and try again */ + /* if our btrfs_bio struct is too small, back off and try again */ if (rw & REQ_WRITE) { if (map->type & (BTRFS_BLOCK_GROUP_RAID1 | BTRFS_BLOCK_GROUP_DUP)) { @@ -2949,11 +2949,11 @@ again: stripes_required = map->num_stripes; } } - if (multi_ret && (rw & (REQ_WRITE | REQ_DISCARD)) && + if (bbio_ret && (rw & (REQ_WRITE | REQ_DISCARD)) && stripes_allocated < stripes_required) { stripes_allocated = map->num_stripes; free_extent_map(em); - kfree(multi); + kfree(bbio); goto again; } stripe_nr = offset; @@ -2982,7 +2982,7 @@ again: *length = em->len - offset; } - if (!multi_ret) + if (!bbio_ret) goto out; num_stripes = 1; @@ -3007,13 +3007,17 @@ again: stripe_index = find_live_mirror(map, 0, map->num_stripes, current->pid % map->num_stripes); + mirror_num = stripe_index + 1; } } else if (map->type & BTRFS_BLOCK_GROUP_DUP) { - if (rw & (REQ_WRITE | REQ_DISCARD)) + if (rw & (REQ_WRITE | REQ_DISCARD)) { num_stripes = map->num_stripes; - else if (mirror_num) + } else if (mirror_num) { stripe_index = mirror_num - 1; + } else { + mirror_num = 1; + } } else if (map->type & BTRFS_BLOCK_GROUP_RAID10) { int factor = map->num_stripes / map->sub_stripes; @@ -3033,6 +3037,7 @@ again: stripe_index = find_live_mirror(map, stripe_index, map->sub_stripes, stripe_index + current->pid % map->sub_stripes); + mirror_num = stripe_index + 1; } } else { /* @@ -3041,15 +3046,16 @@ again: * stripe_index is the number of our device in the stripe array */ stripe_index = do_div(stripe_nr, map->num_stripes); + mirror_num = stripe_index + 1; } BUG_ON(stripe_index >= map->num_stripes); if (rw & REQ_DISCARD) { for (i = 0; i < num_stripes; i++) { - multi->stripes[i].physical = + bbio->stripes[i].physical = map->stripes[stripe_index].physical + stripe_offset + stripe_nr * map->stripe_len; - multi->stripes[i].dev = map->stripes[stripe_index].dev; + bbio->stripes[i].dev = map->stripes[stripe_index].dev; if (map->type & BTRFS_BLOCK_GROUP_RAID0) { u64 stripes; @@ -3070,16 +3076,16 @@ again: } stripes = stripe_nr_end - 1 - j; do_div(stripes, map->num_stripes); - multi->stripes[i].length = map->stripe_len * + bbio->stripes[i].length = map->stripe_len * (stripes - stripe_nr + 1); if (i == 0) { - multi->stripes[i].length -= + bbio->stripes[i].length -= stripe_offset; stripe_offset = 0; } if (stripe_index == last_stripe) - multi->stripes[i].length -= + bbio->stripes[i].length -= stripe_end_offset; } else if (map->type & BTRFS_BLOCK_GROUP_RAID10) { u64 stripes; @@ -3104,11 +3110,11 @@ again: } stripes = stripe_nr_end - 1 - j; do_div(stripes, factor); - multi->stripes[i].length = map->stripe_len * + bbio->stripes[i].length = map->stripe_len * (stripes - stripe_nr + 1); if (i < map->sub_stripes) { - multi->stripes[i].length -= + bbio->stripes[i].length -= stripe_offset; if (i == map->sub_stripes - 1) stripe_offset = 0; @@ -3116,11 +3122,11 @@ again: if (stripe_index >= last_stripe && stripe_index <= (last_stripe + map->sub_stripes - 1)) { - multi->stripes[i].length -= + bbio->stripes[i].length -= stripe_end_offset; } } else - multi->stripes[i].length = *length; + bbio->stripes[i].length = *length; stripe_index++; if (stripe_index == map->num_stripes) { @@ -3131,19 +3137,20 @@ again: } } else { for (i = 0; i < num_stripes; i++) { - multi->stripes[i].physical = + bbio->stripes[i].physical = map->stripes[stripe_index].physical + stripe_offset + stripe_nr * map->stripe_len; - multi->stripes[i].dev = + bbio->stripes[i].dev = map->stripes[stripe_index].dev; stripe_index++; } } - if (multi_ret) { - *multi_ret = multi; - multi->num_stripes = num_stripes; - multi->max_errors = max_errors; + if (bbio_ret) { + *bbio_ret = bbio; + bbio->num_stripes = num_stripes; + bbio->max_errors = max_errors; + bbio->mirror_num = mirror_num; } out: free_extent_map(em); @@ -3152,9 +3159,9 @@ out: int btrfs_map_block(struct btrfs_mapping_tree *map_tree, int rw, u64 logical, u64 *length, - struct btrfs_multi_bio **multi_ret, int mirror_num) + struct btrfs_bio **bbio_ret, int mirror_num) { - return __btrfs_map_block(map_tree, rw, logical, length, multi_ret, + return __btrfs_map_block(map_tree, rw, logical, length, bbio_ret, mirror_num); } @@ -3223,28 +3230,30 @@ int btrfs_rmap_block(struct btrfs_mapping_tree *map_tree, return 0; } -static void end_bio_multi_stripe(struct bio *bio, int err) +static void btrfs_end_bio(struct bio *bio, int err) { - struct btrfs_multi_bio *multi = bio->bi_private; + struct btrfs_bio *bbio = bio->bi_private; int is_orig_bio = 0; if (err) - atomic_inc(&multi->error); + atomic_inc(&bbio->error); - if (bio == multi->orig_bio) + if (bio == bbio->orig_bio) is_orig_bio = 1; - if (atomic_dec_and_test(&multi->stripes_pending)) { + if (atomic_dec_and_test(&bbio->stripes_pending)) { if (!is_orig_bio) { bio_put(bio); - bio = multi->orig_bio; + bio = bbio->orig_bio; } - bio->bi_private = multi->private; - bio->bi_end_io = multi->end_io; + bio->bi_private = bbio->private; + bio->bi_end_io = bbio->end_io; + bio->bi_bdev = (struct block_device *) + (unsigned long)bbio->mirror_num; /* only send an error to the higher layers if it is * beyond the tolerance of the multi-bio */ - if (atomic_read(&multi->error) > multi->max_errors) { + if (atomic_read(&bbio->error) > bbio->max_errors) { err = -EIO; } else if (err) { /* @@ -3254,7 +3263,7 @@ static void end_bio_multi_stripe(struct bio *bio, int err) set_bit(BIO_UPTODATE, &bio->bi_flags); err = 0; } - kfree(multi); + kfree(bbio); bio_endio(bio, err); } else if (!is_orig_bio) { @@ -3334,20 +3343,20 @@ int btrfs_map_bio(struct btrfs_root *root, int rw, struct bio *bio, u64 logical = (u64)bio->bi_sector << 9; u64 length = 0; u64 map_length; - struct btrfs_multi_bio *multi = NULL; int ret; int dev_nr = 0; int total_devs = 1; + struct btrfs_bio *bbio = NULL; length = bio->bi_size; map_tree = &root->fs_info->mapping_tree; map_length = length; - ret = btrfs_map_block(map_tree, rw, logical, &map_length, &multi, + ret = btrfs_map_block(map_tree, rw, logical, &map_length, &bbio, mirror_num); BUG_ON(ret); - total_devs = multi->num_stripes; + total_devs = bbio->num_stripes; if (map_length < length) { printk(KERN_CRIT "mapping failed logical %llu bio len %llu " "len %llu\n", (unsigned long long)logical, @@ -3355,25 +3364,28 @@ int btrfs_map_bio(struct btrfs_root *root, int rw, struct bio *bio, (unsigned long long)map_length); BUG(); } - multi->end_io = first_bio->bi_end_io; - multi->private = first_bio->bi_private; - multi->orig_bio = first_bio; - atomic_set(&multi->stripes_pending, multi->num_stripes); + + bbio->orig_bio = first_bio; + bbio->private = first_bio->bi_private; + bbio->end_io = first_bio->bi_end_io; + atomic_set(&bbio->stripes_pending, bbio->num_stripes); while (dev_nr < total_devs) { - if (total_devs > 1) { - if (dev_nr < total_devs - 1) { - bio = bio_clone(first_bio, GFP_NOFS); - BUG_ON(!bio); - } else { - bio = first_bio; - } - bio->bi_private = multi; - bio->bi_end_io = end_bio_multi_stripe; + if (dev_nr < total_devs - 1) { + bio = bio_clone(first_bio, GFP_NOFS); + BUG_ON(!bio); + } else { + bio = first_bio; } - bio->bi_sector = multi->stripes[dev_nr].physical >> 9; - dev = multi->stripes[dev_nr].dev; + bio->bi_private = bbio; + bio->bi_end_io = btrfs_end_bio; + bio->bi_sector = bbio->stripes[dev_nr].physical >> 9; + dev = bbio->stripes[dev_nr].dev; if (dev && dev->bdev && (rw != WRITE || dev->writeable)) { + pr_debug("btrfs_map_bio: rw %d, secor=%llu, dev=%lu " + "(%s id %llu), size=%u\n", rw, + (u64)bio->bi_sector, (u_long)dev->bdev->bd_dev, + dev->name, dev->devid, bio->bi_size); bio->bi_bdev = dev->bdev; if (async_submit) schedule_bio(root, dev, rw, bio); @@ -3386,8 +3398,6 @@ int btrfs_map_bio(struct btrfs_root *root, int rw, struct bio *bio, } dev_nr++; } - if (total_devs == 1) - kfree(multi); return 0; } diff --git a/fs/btrfs/volumes.h b/fs/btrfs/volumes.h index 2a751246188a..ab5b1c49f352 100644 --- a/fs/btrfs/volumes.h +++ b/fs/btrfs/volumes.h @@ -144,7 +144,10 @@ struct btrfs_bio_stripe { u64 length; /* only used for discard mappings */ }; -struct btrfs_multi_bio { +struct btrfs_bio; +typedef void (btrfs_bio_end_io_t) (struct btrfs_bio *bio, int err); + +struct btrfs_bio { atomic_t stripes_pending; bio_end_io_t *end_io; struct bio *orig_bio; @@ -152,6 +155,7 @@ struct btrfs_multi_bio { atomic_t error; int max_errors; int num_stripes; + int mirror_num; struct btrfs_bio_stripe stripes[]; }; @@ -179,7 +183,7 @@ struct map_lookup { int btrfs_account_dev_extents_size(struct btrfs_device *device, u64 start, u64 end, u64 *length); -#define btrfs_multi_bio_size(n) (sizeof(struct btrfs_multi_bio) + \ +#define btrfs_bio_size(n) (sizeof(struct btrfs_bio) + \ (sizeof(struct btrfs_bio_stripe) * (n))) int btrfs_alloc_dev_extent(struct btrfs_trans_handle *trans, @@ -188,7 +192,7 @@ int btrfs_alloc_dev_extent(struct btrfs_trans_handle *trans, u64 chunk_offset, u64 start, u64 num_bytes); int btrfs_map_block(struct btrfs_mapping_tree *map_tree, int rw, u64 logical, u64 *length, - struct btrfs_multi_bio **multi_ret, int mirror_num); + struct btrfs_bio **bbio_ret, int mirror_num); int btrfs_rmap_block(struct btrfs_mapping_tree *map_tree, u64 chunk_start, u64 physical, u64 devid, u64 **logical, int *naddrs, int *stripe_len);