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Diffstat (limited to 'fs/btrfs/backref.c')
-rw-r--r--fs/btrfs/backref.c299
1 files changed, 240 insertions, 59 deletions
diff --git a/fs/btrfs/backref.c b/fs/btrfs/backref.c
index ff6475f409d6..f3187938e081 100644
--- a/fs/btrfs/backref.c
+++ b/fs/btrfs/backref.c
@@ -16,6 +16,7 @@
* Boston, MA 021110-1307, USA.
*/
+#include <linux/vmalloc.h>
#include "ctree.h"
#include "disk-io.h"
#include "backref.h"
@@ -231,7 +232,7 @@ static int add_all_parents(struct btrfs_root *root, struct btrfs_path *path,
}
if (!ret) {
ret = ulist_add(parents, eb->start,
- (unsigned long)eie, GFP_NOFS);
+ (uintptr_t)eie, GFP_NOFS);
if (ret < 0)
break;
if (!extent_item_pos) {
@@ -363,8 +364,8 @@ static int __resolve_indirect_refs(struct btrfs_fs_info *fs_info,
ULIST_ITER_INIT(&uiter);
node = ulist_next(parents, &uiter);
ref->parent = node ? node->val : 0;
- ref->inode_list =
- node ? (struct extent_inode_elem *)node->aux : 0;
+ ref->inode_list = node ?
+ (struct extent_inode_elem *)(uintptr_t)node->aux : 0;
/* additional parents require new refs being added here */
while ((node = ulist_next(parents, &uiter))) {
@@ -375,8 +376,8 @@ static int __resolve_indirect_refs(struct btrfs_fs_info *fs_info,
}
memcpy(new_ref, ref, sizeof(*ref));
new_ref->parent = node->val;
- new_ref->inode_list =
- (struct extent_inode_elem *)node->aux;
+ new_ref->inode_list = (struct extent_inode_elem *)
+ (uintptr_t)node->aux;
list_add(&new_ref->list, &ref->list);
}
ulist_reinit(parents);
@@ -914,8 +915,8 @@ again:
free_extent_buffer(eb);
}
ret = ulist_add_merge(refs, ref->parent,
- (unsigned long)ref->inode_list,
- (unsigned long *)&eie, GFP_NOFS);
+ (uintptr_t)ref->inode_list,
+ (u64 *)&eie, GFP_NOFS);
if (!ret && extent_item_pos) {
/*
* we've recorded that parent, so we must extend
@@ -959,7 +960,7 @@ static void free_leaf_list(struct ulist *blocks)
while ((node = ulist_next(blocks, &uiter))) {
if (!node->aux)
continue;
- eie = (struct extent_inode_elem *)node->aux;
+ eie = (struct extent_inode_elem *)(uintptr_t)node->aux;
for (; eie; eie = eie_next) {
eie_next = eie->next;
kfree(eie);
@@ -1108,26 +1109,80 @@ static int inode_ref_info(u64 inum, u64 ioff, struct btrfs_root *fs_root,
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!
- */
-char *btrfs_iref_to_path(struct btrfs_root *fs_root, struct btrfs_path *path,
- struct btrfs_inode_ref *iref,
+int btrfs_find_one_extref(struct btrfs_root *root, u64 inode_objectid,
+ u64 start_off, struct btrfs_path *path,
+ struct btrfs_inode_extref **ret_extref,
+ u64 *found_off)
+{
+ int ret, slot;
+ struct btrfs_key key;
+ struct btrfs_key found_key;
+ struct btrfs_inode_extref *extref;
+ struct extent_buffer *leaf;
+ unsigned long ptr;
+
+ key.objectid = inode_objectid;
+ btrfs_set_key_type(&key, BTRFS_INODE_EXTREF_KEY);
+ key.offset = start_off;
+
+ ret = btrfs_search_slot(NULL, root, &key, path, 0, 0);
+ if (ret < 0)
+ return ret;
+
+ while (1) {
+ leaf = path->nodes[0];
+ slot = path->slots[0];
+ if (slot >= btrfs_header_nritems(leaf)) {
+ /*
+ * If the item at offset is not found,
+ * btrfs_search_slot will point us to the slot
+ * where it should be inserted. In our case
+ * that will be the slot directly before the
+ * next INODE_REF_KEY_V2 item. In the case
+ * that we're pointing to the last slot in a
+ * leaf, we must move one leaf over.
+ */
+ ret = btrfs_next_leaf(root, path);
+ if (ret) {
+ if (ret >= 1)
+ ret = -ENOENT;
+ break;
+ }
+ continue;
+ }
+
+ btrfs_item_key_to_cpu(leaf, &found_key, slot);
+
+ /*
+ * Check that we're still looking at an extended ref key for
+ * this particular objectid. If we have different
+ * objectid or type then there are no more to be found
+ * in the tree and we can exit.
+ */
+ ret = -ENOENT;
+ if (found_key.objectid != inode_objectid)
+ break;
+ if (btrfs_key_type(&found_key) != BTRFS_INODE_EXTREF_KEY)
+ break;
+
+ ret = 0;
+ ptr = btrfs_item_ptr_offset(leaf, path->slots[0]);
+ extref = (struct btrfs_inode_extref *)ptr;
+ *ret_extref = extref;
+ if (found_off)
+ *found_off = found_key.offset;
+ break;
+ }
+
+ return ret;
+}
+
+static char *ref_to_path(struct btrfs_root *fs_root,
+ struct btrfs_path *path,
+ u32 name_len, unsigned long name_off,
struct extent_buffer *eb_in, u64 parent,
char *dest, u32 size)
{
- u32 len;
int slot;
u64 next_inum;
int ret;
@@ -1135,17 +1190,17 @@ char *btrfs_iref_to_path(struct btrfs_root *fs_root, struct btrfs_path *path,
struct extent_buffer *eb = eb_in;
struct btrfs_key found_key;
int leave_spinning = path->leave_spinning;
+ struct btrfs_inode_ref *iref;
if (bytes_left >= 0)
dest[bytes_left] = '\0';
path->leave_spinning = 1;
while (1) {
- len = btrfs_inode_ref_name_len(eb, iref);
- bytes_left -= len;
+ bytes_left -= name_len;
if (bytes_left >= 0)
read_extent_buffer(eb, dest + bytes_left,
- (unsigned long)(iref + 1), len);
+ name_off, name_len);
if (eb != eb_in) {
btrfs_tree_read_unlock_blocking(eb);
free_extent_buffer(eb);
@@ -1155,6 +1210,7 @@ char *btrfs_iref_to_path(struct btrfs_root *fs_root, struct btrfs_path *path,
ret = -ENOENT;
if (ret)
break;
+
next_inum = found_key.offset;
/* regular exit ahead */
@@ -1170,8 +1226,11 @@ char *btrfs_iref_to_path(struct btrfs_root *fs_root, struct btrfs_path *path,
btrfs_set_lock_blocking_rw(eb, BTRFS_READ_LOCK);
}
btrfs_release_path(path);
-
iref = btrfs_item_ptr(eb, slot, struct btrfs_inode_ref);
+
+ name_len = btrfs_inode_ref_name_len(eb, iref);
+ name_off = (unsigned long)(iref + 1);
+
parent = next_inum;
--bytes_left;
if (bytes_left >= 0)
@@ -1188,12 +1247,39 @@ char *btrfs_iref_to_path(struct btrfs_root *fs_root, struct btrfs_path *path,
}
/*
+ * 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!
+ */
+char *btrfs_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)
+{
+ return ref_to_path(fs_root, path,
+ btrfs_inode_ref_name_len(eb_in, iref),
+ (unsigned long)(iref + 1),
+ eb_in, parent, dest, size);
+}
+
+/*
* 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)
+ struct btrfs_path *path, struct btrfs_key *found_key,
+ u64 *flags_ret)
{
int ret;
u64 flags;
@@ -1237,10 +1323,17 @@ int extent_from_logical(struct btrfs_fs_info *fs_info, u64 logical,
(unsigned long long)found_key->objectid,
(unsigned long long)found_key->offset,
(unsigned long long)flags, item_size);
- if (flags & BTRFS_EXTENT_FLAG_TREE_BLOCK)
- return BTRFS_EXTENT_FLAG_TREE_BLOCK;
- if (flags & BTRFS_EXTENT_FLAG_DATA)
- return BTRFS_EXTENT_FLAG_DATA;
+
+ WARN_ON(!flags_ret);
+ if (flags_ret) {
+ if (flags & BTRFS_EXTENT_FLAG_TREE_BLOCK)
+ *flags_ret = BTRFS_EXTENT_FLAG_TREE_BLOCK;
+ else if (flags & BTRFS_EXTENT_FLAG_DATA)
+ *flags_ret = BTRFS_EXTENT_FLAG_DATA;
+ else
+ BUG_ON(1);
+ return 0;
+ }
return -EIO;
}
@@ -1404,12 +1497,13 @@ int iterate_extent_inodes(struct btrfs_fs_info *fs_info,
ULIST_ITER_INIT(&root_uiter);
while (!ret && (root_node = ulist_next(roots, &root_uiter))) {
pr_debug("root %llu references leaf %llu, data list "
- "%#lx\n", root_node->val, ref_node->val,
- ref_node->aux);
- ret = iterate_leaf_refs(
- (struct extent_inode_elem *)ref_node->aux,
- root_node->val, extent_item_objectid,
- iterate, ctx);
+ "%#llx\n", root_node->val, ref_node->val,
+ (long long)ref_node->aux);
+ ret = iterate_leaf_refs((struct extent_inode_elem *)
+ (uintptr_t)ref_node->aux,
+ root_node->val,
+ extent_item_objectid,
+ iterate, ctx);
}
ulist_free(roots);
roots = NULL;
@@ -1432,15 +1526,15 @@ int iterate_inodes_from_logical(u64 logical, struct btrfs_fs_info *fs_info,
{
int ret;
u64 extent_item_pos;
+ u64 flags = 0;
struct btrfs_key found_key;
int search_commit_root = path->search_commit_root;
- ret = extent_from_logical(fs_info, logical, path,
- &found_key);
+ ret = extent_from_logical(fs_info, logical, path, &found_key, &flags);
btrfs_release_path(path);
if (ret < 0)
return ret;
- if (ret & BTRFS_EXTENT_FLAG_TREE_BLOCK)
+ if (flags & BTRFS_EXTENT_FLAG_TREE_BLOCK)
return -EINVAL;
extent_item_pos = logical - found_key.objectid;
@@ -1451,9 +1545,12 @@ int iterate_inodes_from_logical(u64 logical, struct btrfs_fs_info *fs_info,
return ret;
}
-static int iterate_irefs(u64 inum, struct btrfs_root *fs_root,
- struct btrfs_path *path,
- iterate_irefs_t *iterate, void *ctx)
+typedef int (iterate_irefs_t)(u64 parent, u32 name_len, unsigned long name_off,
+ struct extent_buffer *eb, void *ctx);
+
+static int iterate_inode_refs(u64 inum, struct btrfs_root *fs_root,
+ struct btrfs_path *path,
+ iterate_irefs_t *iterate, void *ctx)
{
int ret = 0;
int slot;
@@ -1470,7 +1567,7 @@ static int iterate_irefs(u64 inum, struct btrfs_root *fs_root,
while (!ret) {
path->leave_spinning = 1;
ret = inode_ref_info(inum, parent ? parent+1 : 0, fs_root, path,
- &found_key);
+ &found_key);
if (ret < 0)
break;
if (ret) {
@@ -1498,7 +1595,8 @@ static int iterate_irefs(u64 inum, struct btrfs_root *fs_root,
"tree %llu\n", cur,
(unsigned long long)found_key.objectid,
(unsigned long long)fs_root->objectid);
- ret = iterate(parent, iref, eb, ctx);
+ ret = iterate(parent, name_len,
+ (unsigned long)(iref + 1), eb, ctx);
if (ret)
break;
len = sizeof(*iref) + name_len;
@@ -1513,12 +1611,98 @@ static int iterate_irefs(u64 inum, struct btrfs_root *fs_root,
return ret;
}
+static int iterate_inode_extrefs(u64 inum, struct btrfs_root *fs_root,
+ struct btrfs_path *path,
+ iterate_irefs_t *iterate, void *ctx)
+{
+ int ret;
+ int slot;
+ u64 offset = 0;
+ u64 parent;
+ int found = 0;
+ struct extent_buffer *eb;
+ struct btrfs_inode_extref *extref;
+ struct extent_buffer *leaf;
+ u32 item_size;
+ u32 cur_offset;
+ unsigned long ptr;
+
+ while (1) {
+ ret = btrfs_find_one_extref(fs_root, inum, offset, path, &extref,
+ &offset);
+ if (ret < 0)
+ break;
+ if (ret) {
+ ret = found ? 0 : -ENOENT;
+ break;
+ }
+ ++found;
+
+ slot = path->slots[0];
+ eb = path->nodes[0];
+ /* make sure we can use eb after releasing the path */
+ atomic_inc(&eb->refs);
+
+ btrfs_tree_read_lock(eb);
+ btrfs_set_lock_blocking_rw(eb, BTRFS_READ_LOCK);
+ btrfs_release_path(path);
+
+ leaf = path->nodes[0];
+ item_size = btrfs_item_size_nr(leaf, path->slots[0]);
+ ptr = btrfs_item_ptr_offset(leaf, path->slots[0]);
+ cur_offset = 0;
+
+ while (cur_offset < item_size) {
+ u32 name_len;
+
+ extref = (struct btrfs_inode_extref *)(ptr + cur_offset);
+ parent = btrfs_inode_extref_parent(eb, extref);
+ name_len = btrfs_inode_extref_name_len(eb, extref);
+ ret = iterate(parent, name_len,
+ (unsigned long)&extref->name, eb, ctx);
+ if (ret)
+ break;
+
+ cur_offset += btrfs_inode_extref_name_len(leaf, extref);
+ cur_offset += sizeof(*extref);
+ }
+ btrfs_tree_read_unlock_blocking(eb);
+ free_extent_buffer(eb);
+
+ offset++;
+ }
+
+ btrfs_release_path(path);
+
+ 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 found_refs = 0;
+
+ ret = iterate_inode_refs(inum, fs_root, path, iterate, ctx);
+ if (!ret)
+ ++found_refs;
+ else if (ret != -ENOENT)
+ return ret;
+
+ ret = iterate_inode_extrefs(inum, fs_root, path, iterate, ctx);
+ if (ret == -ENOENT && found_refs)
+ return 0;
+
+ 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)
+static int inode_to_path(u64 inum, u32 name_len, unsigned long name_off,
+ struct extent_buffer *eb, void *ctx)
{
struct inode_fs_paths *ipath = ctx;
char *fspath;
@@ -1531,20 +1715,17 @@ static int inode_to_path(u64 inum, struct btrfs_inode_ref *iref,
ipath->fspath->bytes_left - s_ptr : 0;
fspath_min = (char *)ipath->fspath->val + (i + 1) * s_ptr;
- fspath = btrfs_iref_to_path(ipath->fs_root, ipath->btrfs_path, iref, eb,
- inum, fspath_min, bytes_left);
+ fspath = ref_to_path(ipath->fs_root, ipath->btrfs_path, name_len,
+ name_off, eb, inum, fspath_min,
+ bytes_left);
if (IS_ERR(fspath))
return PTR_ERR(fspath);
if (fspath > fspath_min) {
- pr_debug("path resolved: %s\n", fspath);
ipath->fspath->val[i] = (u64)(unsigned long)fspath;
++ipath->fspath->elem_cnt;
ipath->fspath->bytes_left = fspath - fspath_min;
} else {
- pr_debug("missed path, not enough space. missing bytes: %lu, "
- "constructed so far: %s\n",
- (unsigned long)(fspath_min - fspath), fspath_min);
++ipath->fspath->elem_missed;
ipath->fspath->bytes_missing += fspath_min - fspath;
ipath->fspath->bytes_left = 0;
@@ -1566,7 +1747,7 @@ static int inode_to_path(u64 inum, struct btrfs_inode_ref *iref,
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);
+ inode_to_path, ipath);
}
struct btrfs_data_container *init_data_container(u32 total_bytes)
@@ -1575,7 +1756,7 @@ struct btrfs_data_container *init_data_container(u32 total_bytes)
size_t alloc_bytes;
alloc_bytes = max_t(size_t, total_bytes, sizeof(*data));
- data = kmalloc(alloc_bytes, GFP_NOFS);
+ data = vmalloc(alloc_bytes);
if (!data)
return ERR_PTR(-ENOMEM);
@@ -1626,6 +1807,6 @@ void free_ipath(struct inode_fs_paths *ipath)
{
if (!ipath)
return;
- kfree(ipath->fspath);
+ vfree(ipath->fspath);
kfree(ipath);
}
generated by cgit v1.2.3 (git 2.39.0) at 2024-12-22 22:08:43 +0300