Bug#691568: btrfs: can't have many hardlinks to a given inode in a given directory
Jonathan Nieder wrote:
> b916a59adfdc Btrfs: add missing read locks in backref.c
> 5a1d7843ca4b btrfs: improved readablity for add_inode_ref
> f186373fef00 btrfs: extended inode refs
> d24bec3ae528 btrfs: extended inode ref iteration
>
> Untested. Patches attached for reference.
Attached.
From: Jan Schmidt <list.btrfs@jan-o-sch.net>
Date: Fri, 13 Apr 2012 12:28:08 +0200
Subject: Btrfs: add missing read locks in backref.c
commit b916a59adfdc875381b68ced258694b434cf43ae upstream.
iref_to_path and iterate_irefs both increment the eb's refcount to use it
after releasing the path. Both depend on consistent data remaining in the
extent buffer and need a read lock to protect it.
Signed-off-by: Jan Schmidt <list.btrfs@jan-o-sch.net>
Signed-off-by: Jonathan Nieder <jrnieder@gmail.com>
---
fs/btrfs/backref.c | 17 +++++++++++++++--
1 file changed, 15 insertions(+), 2 deletions(-)
diff --git a/fs/btrfs/backref.c b/fs/btrfs/backref.c
index 22c64fff1bd5..645ed8fd7f82 100644
--- a/fs/btrfs/backref.c
+++ b/fs/btrfs/backref.c
@@ -19,6 +19,7 @@
#include "ctree.h"
#include "disk-io.h"
#include "backref.h"
+#include "locking.h"
struct __data_ref {
struct list_head list;
@@ -108,18 +109,22 @@ static char *iref_to_path(struct btrfs_root *fs_root, struct btrfs_path *path,
s64 bytes_left = size - 1;
struct extent_buffer *eb = eb_in;
struct btrfs_key found_key;
+ int leave_spinning = path->leave_spinning;
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;
if (bytes_left >= 0)
read_extent_buffer(eb, dest + bytes_left,
(unsigned long)(iref + 1), len);
- if (eb != eb_in)
+ if (eb != eb_in) {
+ btrfs_tree_read_unlock_blocking(eb);
free_extent_buffer(eb);
+ }
ret = inode_ref_info(parent, 0, fs_root, path, &found_key);
if (ret)
break;
@@ -132,8 +137,11 @@ static char *iref_to_path(struct btrfs_root *fs_root, struct btrfs_path *path,
slot = path->slots[0];
eb = path->nodes[0];
/* make sure we can use eb after releasing the path */
- if (eb != eb_in)
+ if (eb != eb_in) {
atomic_inc(&eb->refs);
+ btrfs_tree_read_lock(eb);
+ btrfs_set_lock_blocking_rw(eb, BTRFS_READ_LOCK);
+ }
btrfs_release_path(path);
iref = btrfs_item_ptr(eb, slot, struct btrfs_inode_ref);
@@ -144,6 +152,7 @@ static char *iref_to_path(struct btrfs_root *fs_root, struct btrfs_path *path,
}
btrfs_release_path(path);
+ path->leave_spinning = leave_spinning;
if (ret)
return ERR_PTR(ret);
@@ -620,6 +629,7 @@ static int iterate_irefs(u64 inum, struct btrfs_root *fs_root,
struct btrfs_key found_key;
while (1) {
+ path->leave_spinning = 1;
ret = inode_ref_info(inum, parent ? parent+1 : 0, fs_root, path,
&found_key);
if (ret < 0)
@@ -635,6 +645,8 @@ static int iterate_irefs(u64 inum, struct btrfs_root *fs_root,
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);
item = btrfs_item_nr(eb, slot);
@@ -651,6 +663,7 @@ static int iterate_irefs(u64 inum, struct btrfs_root *fs_root,
len = sizeof(*iref) + name_len;
iref = (struct btrfs_inode_ref *)((char *)iref + len);
}
+ btrfs_tree_read_unlock_blocking(eb);
free_extent_buffer(eb);
}
--
1.8.0
From: Jan Schmidt <list.btrfs@jan-o-sch.net>
Date: Fri, 17 Aug 2012 14:04:41 -0700
Subject: btrfs: improved readablity for add_inode_ref
commit 5a1d7843ca4b3a9009bea87f85ad33854b910aea upstream.
Moved part of the code into a sub function and replaced most of the gotos
by ifs, hoping that it will be easier to read now.
Signed-off-by: Jan Schmidt <list.btrfs@jan-o-sch.net>
Signed-off-by: Mark Fasheh <mfasheh@suse.de>
Signed-off-by: Jonathan Nieder <jrnieder@gmail.com>
---
fs/btrfs/tree-log.c | 182 ++++++++++++++++++++++++++++------------------------
1 file changed, 99 insertions(+), 83 deletions(-)
diff --git a/fs/btrfs/tree-log.c b/fs/btrfs/tree-log.c
index 19b127c15486..883cdc1c357b 100644
--- a/fs/btrfs/tree-log.c
+++ b/fs/btrfs/tree-log.c
@@ -788,76 +788,18 @@ out:
return match;
}
-
-/*
- * replay one inode back reference item found in the log tree.
- * eb, slot and key refer to the buffer and key found in the log tree.
- * root is the destination we are replaying into, and path is for temp
- * use by this function. (it should be released on return).
- */
-static noinline int add_inode_ref(struct btrfs_trans_handle *trans,
+static inline int __add_inode_ref(struct btrfs_trans_handle *trans,
struct btrfs_root *root,
- struct btrfs_root *log,
struct btrfs_path *path,
- struct extent_buffer *eb, int slot,
- struct btrfs_key *key)
+ struct btrfs_root *log_root,
+ struct inode *dir, struct inode *inode,
+ struct btrfs_key *key,
+ struct extent_buffer *eb,
+ struct btrfs_inode_ref *ref,
+ char *name, int namelen, int *search_done)
{
- struct btrfs_inode_ref *ref;
- struct btrfs_dir_item *di;
- struct inode *dir;
- struct inode *inode;
- unsigned long ref_ptr;
- unsigned long ref_end;
- char *name;
- int namelen;
int ret;
- int search_done = 0;
-
- /*
- * it is possible that we didn't log all the parent directories
- * for a given inode. If we don't find the dir, just don't
- * copy the back ref in. The link count fixup code will take
- * care of the rest
- */
- dir = read_one_inode(root, key->offset);
- if (!dir)
- return -ENOENT;
-
- inode = read_one_inode(root, key->objectid);
- if (!inode) {
- iput(dir);
- return -EIO;
- }
-
- ref_ptr = btrfs_item_ptr_offset(eb, slot);
- ref_end = ref_ptr + btrfs_item_size_nr(eb, slot);
-
-again:
- ref = (struct btrfs_inode_ref *)ref_ptr;
-
- namelen = btrfs_inode_ref_name_len(eb, ref);
- name = kmalloc(namelen, GFP_NOFS);
- BUG_ON(!name);
-
- read_extent_buffer(eb, name, (unsigned long)(ref + 1), namelen);
-
- /* if we already have a perfect match, we're done */
- if (inode_in_dir(root, path, btrfs_ino(dir), btrfs_ino(inode),
- btrfs_inode_ref_index(eb, ref),
- name, namelen)) {
- goto out;
- }
-
- /*
- * look for a conflicting back reference in the metadata.
- * if we find one we have to unlink that name of the file
- * before we add our new link. Later on, we overwrite any
- * existing back reference, and we don't want to create
- * dangling pointers in the directory.
- */
-
- if (search_done)
- goto insert;
+ struct btrfs_dir_item *di;
ret = btrfs_search_slot(NULL, root, key, path, 0, 0);
if (ret == 0) {
@@ -872,7 +814,7 @@ again:
* if so, just jump out, we're done
*/
if (key->objectid == key->offset)
- goto out_nowrite;
+ return 1;
/* check all the names in this back reference to see
* if they are in the log. if so, we allow them to stay
@@ -891,7 +833,7 @@ again:
(unsigned long)(victim_ref + 1),
victim_name_len);
- if (!backref_in_log(log, key, victim_name,
+ if (!backref_in_log(log_root, key, victim_name,
victim_name_len)) {
btrfs_inc_nlink(inode);
btrfs_release_path(path);
@@ -910,7 +852,7 @@ again:
* NOTE: we have searched root tree and checked the
* coresponding ref, it does not need to check again.
*/
- search_done = 1;
+ *search_done = 1;
}
btrfs_release_path(path);
@@ -933,25 +875,99 @@ again:
}
btrfs_release_path(path);
-insert:
- /* insert our name */
- ret = btrfs_add_link(trans, dir, inode, name, namelen, 0,
- btrfs_inode_ref_index(eb, ref));
- BUG_ON(ret);
-
- btrfs_update_inode(trans, root, inode);
-
-out:
- ref_ptr = (unsigned long)(ref + 1) + namelen;
- kfree(name);
- if (ref_ptr < ref_end)
- goto again;
+ return 0;
+}
+
+/*
+ * replay one inode back reference item found in the log tree.
+ * eb, slot and key refer to the buffer and key found in the log tree.
+ * root is the destination we are replaying into, and path is for temp
+ * use by this function. (it should be released on return).
+ */
+static noinline int add_inode_ref(struct btrfs_trans_handle *trans,
+ struct btrfs_root *root,
+ struct btrfs_root *log,
+ struct btrfs_path *path,
+ struct extent_buffer *eb, int slot,
+ struct btrfs_key *key)
+{
+ struct btrfs_inode_ref *ref;
+ struct inode *dir;
+ struct inode *inode;
+ unsigned long ref_ptr;
+ unsigned long ref_end;
+ char *name;
+ int namelen;
+ int ret;
+ int search_done = 0;
+
+ /*
+ * it is possible that we didn't log all the parent directories
+ * for a given inode. If we don't find the dir, just don't
+ * copy the back ref in. The link count fixup code will take
+ * care of the rest
+ */
+ dir = read_one_inode(root, key->offset);
+ if (!dir)
+ return -ENOENT;
+
+ inode = read_one_inode(root, key->objectid);
+ if (!inode) {
+ iput(dir);
+ return -EIO;
+ }
+
+ ref_ptr = btrfs_item_ptr_offset(eb, slot);
+ ref_end = ref_ptr + btrfs_item_size_nr(eb, slot);
+
+ while (ref_ptr < ref_end) {
+ ref = (struct btrfs_inode_ref *)ref_ptr;
+
+ namelen = btrfs_inode_ref_name_len(eb, ref);
+ name = kmalloc(namelen, GFP_NOFS);
+ BUG_ON(!name);
+
+ read_extent_buffer(eb, name, (unsigned long)(ref + 1), namelen);
+
+ /* if we already have a perfect match, we're done */
+ if (!inode_in_dir(root, path, btrfs_ino(dir), btrfs_ino(inode),
+ btrfs_inode_ref_index(eb, ref),
+ name, namelen)) {
+ /*
+ * look for a conflicting back reference in the
+ * metadata. if we find one we have to unlink that name
+ * of the file before we add our new link. Later on, we
+ * overwrite any existing back reference, and we don't
+ * want to create dangling pointers in the directory.
+ */
+
+ if (!search_done) {
+ ret = __add_inode_ref(trans, root, path, log,
+ dir, inode, key, eb, ref,
+ name, namelen,
+ &search_done);
+ if (ret == 1)
+ goto out;
+ BUG_ON(ret);
+ }
+
+ /* insert our name */
+ ret = btrfs_add_link(trans, dir, inode, name, namelen,
+ 0, btrfs_inode_ref_index(eb, ref));
+ BUG_ON(ret);
+
+ btrfs_update_inode(trans, root, inode);
+ }
+
+ ref_ptr = (unsigned long)(ref + 1) + namelen;
+ kfree(name);
+ }
/* finally write the back reference in the inode */
ret = overwrite_item(trans, root, path, eb, slot, key);
BUG_ON(ret);
-out_nowrite:
+out:
btrfs_release_path(path);
iput(dir);
iput(inode);
--
1.8.0
From: Mark Fasheh <mfasheh@suse.de>
Date: Wed, 8 Aug 2012 11:32:27 -0700
Subject: btrfs: extended inode refs
commit f186373fef005cee948a4a39e6a14c2e5f517298 upstream.
This patch adds basic support for extended inode refs. This includes support
for link and unlink of the refs, which basically gets us support for rename
as well.
Inode creation does not need changing - extended refs are only added after
the ref array is full.
Signed-off-by: Mark Fasheh <mfasheh@suse.de>
Signed-off-by: Jonathan Nieder <jrnieder@gmail.com>
---
fs/btrfs/backref.c | 68 ++++++++++
fs/btrfs/backref.h | 5 +
fs/btrfs/ctree.h | 53 +++++++-
fs/btrfs/hash.h | 10 ++
fs/btrfs/inode-item.c | 282 +++++++++++++++++++++++++++++++++++++++--
fs/btrfs/inode.c | 23 ++--
fs/btrfs/tree-log.c | 345 ++++++++++++++++++++++++++++++++++++++++++--------
7 files changed, 709 insertions(+), 77 deletions(-)
diff --git a/fs/btrfs/backref.c b/fs/btrfs/backref.c
index 645ed8fd7f82..dd4ac08a3856 100644
--- a/fs/btrfs/backref.c
+++ b/fs/btrfs/backref.c
@@ -83,6 +83,74 @@ static int inode_ref_info(u64 inum, u64 ioff, struct btrfs_root *fs_root,
found_key);
}
+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;
+}
+
/*
* 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
diff --git a/fs/btrfs/backref.h b/fs/btrfs/backref.h
index 92618837cb8f..a81642d33934 100644
--- a/fs/btrfs/backref.h
+++ b/fs/btrfs/backref.h
@@ -59,4 +59,9 @@ 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);
+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);
+
#endif
diff --git a/fs/btrfs/ctree.h b/fs/btrfs/ctree.h
index 83a871ffe092..f68b68c8090c 100644
--- a/fs/btrfs/ctree.h
+++ b/fs/btrfs/ctree.h
@@ -140,6 +140,13 @@ struct btrfs_ordered_sum;
*/
#define BTRFS_NAME_LEN 255
+/*
+ * Theoretical limit is larger, but we keep this down to a sane
+ * value. That should limit greatly the possibility of collisions on
+ * inode ref items.
+ */
+#define BTRFS_LINK_MAX 65535U
+
/* 32 bytes in various csum fields */
#define BTRFS_CSUM_SIZE 32
@@ -459,13 +466,16 @@ struct btrfs_super_block {
#define BTRFS_FEATURE_INCOMPAT_MIXED_GROUPS (1ULL << 2)
#define BTRFS_FEATURE_INCOMPAT_COMPRESS_LZO (1ULL << 3)
+#define BTRFS_FEATURE_INCOMPAT_EXTENDED_IREF (1ULL << 6)
+
#define BTRFS_FEATURE_COMPAT_SUPP 0ULL
#define BTRFS_FEATURE_COMPAT_RO_SUPP 0ULL
#define BTRFS_FEATURE_INCOMPAT_SUPP \
(BTRFS_FEATURE_INCOMPAT_MIXED_BACKREF | \
BTRFS_FEATURE_INCOMPAT_DEFAULT_SUBVOL | \
BTRFS_FEATURE_INCOMPAT_MIXED_GROUPS | \
- BTRFS_FEATURE_INCOMPAT_COMPRESS_LZO)
+ BTRFS_FEATURE_INCOMPAT_COMPRESS_LZO | \
+ BTRFS_FEATURE_INCOMPAT_EXTENDED_IREF)
/*
* A leaf is full of items. offset and size tell us where to find
@@ -612,6 +622,14 @@ struct btrfs_inode_ref {
/* name goes here */
} __attribute__ ((__packed__));
+struct btrfs_inode_extref {
+ __le64 parent_objectid;
+ __le64 index;
+ __le16 name_len;
+ __u8 name[0];
+ /* name goes here */
+} __attribute__ ((__packed__));
+
struct btrfs_timespec {
__le64 sec;
__le32 nsec;
@@ -1315,6 +1333,7 @@ struct btrfs_ioctl_defrag_range_args {
*/
#define BTRFS_INODE_ITEM_KEY 1
#define BTRFS_INODE_REF_KEY 12
+#define BTRFS_INODE_EXTREF_KEY 13
#define BTRFS_XATTR_ITEM_KEY 24
#define BTRFS_ORPHAN_ITEM_KEY 48
/* reserve 2-15 close to the inode for later flexibility */
@@ -1611,6 +1630,13 @@ BTRFS_SETGET_STACK_FUNCS(block_group_flags,
BTRFS_SETGET_FUNCS(inode_ref_name_len, struct btrfs_inode_ref, name_len, 16);
BTRFS_SETGET_FUNCS(inode_ref_index, struct btrfs_inode_ref, index, 64);
+/* struct btrfs_inode_extref */
+BTRFS_SETGET_FUNCS(inode_extref_parent, struct btrfs_inode_extref,
+ parent_objectid, 64);
+BTRFS_SETGET_FUNCS(inode_extref_name_len, struct btrfs_inode_extref,
+ name_len, 16);
+BTRFS_SETGET_FUNCS(inode_extref_index, struct btrfs_inode_extref, index, 64);
+
/* struct btrfs_inode_item */
BTRFS_SETGET_FUNCS(inode_generation, struct btrfs_inode_item, generation, 64);
BTRFS_SETGET_FUNCS(inode_sequence, struct btrfs_inode_item, sequence, 64);
@@ -2596,12 +2622,12 @@ int btrfs_del_inode_ref(struct btrfs_trans_handle *trans,
struct btrfs_root *root,
const char *name, int name_len,
u64 inode_objectid, u64 ref_objectid, u64 *index);
-struct btrfs_inode_ref *
-btrfs_lookup_inode_ref(struct btrfs_trans_handle *trans,
- struct btrfs_root *root,
- struct btrfs_path *path,
- const char *name, int name_len,
- u64 inode_objectid, u64 ref_objectid, int mod);
+int btrfs_get_inode_ref_index(struct btrfs_trans_handle *trans,
+ struct btrfs_root *root,
+ struct btrfs_path *path,
+ const char *name, int name_len,
+ u64 inode_objectid, u64 ref_objectid, int mod,
+ u64 *ret_index);
int btrfs_insert_empty_inode(struct btrfs_trans_handle *trans,
struct btrfs_root *root,
struct btrfs_path *path, u64 objectid);
@@ -2609,6 +2635,19 @@ int btrfs_lookup_inode(struct btrfs_trans_handle *trans, struct btrfs_root
*root, struct btrfs_path *path,
struct btrfs_key *location, int mod);
+struct btrfs_inode_extref *
+btrfs_lookup_inode_extref(struct btrfs_trans_handle *trans,
+ struct btrfs_root *root,
+ struct btrfs_path *path,
+ const char *name, int name_len,
+ u64 inode_objectid, u64 ref_objectid, int ins_len,
+ int cow);
+
+int btrfs_find_name_in_ext_backref(struct btrfs_path *path,
+ u64 ref_objectid, const char *name,
+ int name_len,
+ struct btrfs_inode_extref **extref_ret);
+
/* file-item.c */
int btrfs_del_csums(struct btrfs_trans_handle *trans,
struct btrfs_root *root, u64 bytenr, u64 len);
diff --git a/fs/btrfs/hash.h b/fs/btrfs/hash.h
index db2ff9773b99..1d982812ab67 100644
--- a/fs/btrfs/hash.h
+++ b/fs/btrfs/hash.h
@@ -24,4 +24,14 @@ static inline u64 btrfs_name_hash(const char *name, int len)
{
return crc32c((u32)~1, name, len);
}
+
+/*
+ * Figure the key offset of an extended inode ref
+ */
+static inline u64 btrfs_extref_hash(u64 parent_objectid, const char *name,
+ int len)
+{
+ return (u64) crc32c(parent_objectid, name, len);
+}
+
#endif
diff --git a/fs/btrfs/inode-item.c b/fs/btrfs/inode-item.c
index baa74f3db691..7f89e4a9ec68 100644
--- a/fs/btrfs/inode-item.c
+++ b/fs/btrfs/inode-item.c
@@ -18,6 +18,7 @@
#include "ctree.h"
#include "disk-io.h"
+#include "hash.h"
#include "transaction.h"
static int find_name_in_backref(struct btrfs_path *path, const char *name,
@@ -49,18 +50,57 @@ static int find_name_in_backref(struct btrfs_path *path, const char *name,
return 0;
}
-struct btrfs_inode_ref *
+int btrfs_find_name_in_ext_backref(struct btrfs_path *path, u64 ref_objectid,
+ const char *name, int name_len,
+ struct btrfs_inode_extref **extref_ret)
+{
+ struct extent_buffer *leaf;
+ struct btrfs_inode_extref *extref;
+ unsigned long ptr;
+ unsigned long name_ptr;
+ u32 item_size;
+ u32 cur_offset = 0;
+ int ref_name_len;
+
+ leaf = path->nodes[0];
+ item_size = btrfs_item_size_nr(leaf, path->slots[0]);
+ ptr = btrfs_item_ptr_offset(leaf, path->slots[0]);
+
+ /*
+ * Search all extended backrefs in this item. We're only
+ * looking through any collisions so most of the time this is
+ * just going to compare against one buffer. If all is well,
+ * we'll return success and the inode ref object.
+ */
+ while (cur_offset < item_size) {
+ extref = (struct btrfs_inode_extref *) (ptr + cur_offset);
+ name_ptr = (unsigned long)(&extref->name);
+ ref_name_len = btrfs_inode_extref_name_len(leaf, extref);
+
+ if (ref_name_len == name_len &&
+ btrfs_inode_extref_parent(leaf, extref) == ref_objectid &&
+ (memcmp_extent_buffer(leaf, name, name_ptr, name_len) == 0)) {
+ if (extref_ret)
+ *extref_ret = extref;
+ return 1;
+ }
+
+ cur_offset += ref_name_len + sizeof(*extref);
+ }
+ return 0;
+}
+
+static struct btrfs_inode_ref *
btrfs_lookup_inode_ref(struct btrfs_trans_handle *trans,
- struct btrfs_root *root,
- struct btrfs_path *path,
- const char *name, int name_len,
- u64 inode_objectid, u64 ref_objectid, int mod)
+ struct btrfs_root *root,
+ struct btrfs_path *path,
+ const char *name, int name_len,
+ u64 inode_objectid, u64 ref_objectid, int ins_len,
+ int cow)
{
+ int ret;
struct btrfs_key key;
struct btrfs_inode_ref *ref;
- int ins_len = mod < 0 ? -1 : 0;
- int cow = mod != 0;
- int ret;
key.objectid = inode_objectid;
key.type = BTRFS_INODE_REF_KEY;
@@ -76,13 +116,150 @@ btrfs_lookup_inode_ref(struct btrfs_trans_handle *trans,
return ref;
}
-int btrfs_del_inode_ref(struct btrfs_trans_handle *trans,
+/* Returns NULL if no extref found */
+struct btrfs_inode_extref *
+btrfs_lookup_inode_extref(struct btrfs_trans_handle *trans,
+ struct btrfs_root *root,
+ struct btrfs_path *path,
+ const char *name, int name_len,
+ u64 inode_objectid, u64 ref_objectid, int ins_len,
+ int cow)
+{
+ int ret;
+ struct btrfs_key key;
+ struct btrfs_inode_extref *extref;
+
+ key.objectid = inode_objectid;
+ key.type = BTRFS_INODE_EXTREF_KEY;
+ key.offset = btrfs_extref_hash(ref_objectid, name, name_len);
+
+ ret = btrfs_search_slot(trans, root, &key, path, ins_len, cow);
+ if (ret < 0)
+ return ERR_PTR(ret);
+ if (ret > 0)
+ return NULL;
+ if (!btrfs_find_name_in_ext_backref(path, ref_objectid, name, name_len, &extref))
+ return NULL;
+ return extref;
+}
+
+int btrfs_get_inode_ref_index(struct btrfs_trans_handle *trans,
+ struct btrfs_root *root,
+ struct btrfs_path *path,
+ const char *name, int name_len,
+ u64 inode_objectid, u64 ref_objectid, int mod,
+ u64 *ret_index)
+{
+ struct btrfs_inode_ref *ref;
+ struct btrfs_inode_extref *extref;
+ int ins_len = mod < 0 ? -1 : 0;
+ int cow = mod != 0;
+
+ ref = btrfs_lookup_inode_ref(trans, root, path, name, name_len,
+ inode_objectid, ref_objectid, ins_len,
+ cow);
+ if (IS_ERR(ref))
+ return PTR_ERR(ref);
+
+ if (ref != NULL) {
+ *ret_index = btrfs_inode_ref_index(path->nodes[0], ref);
+ return 0;
+ }
+
+ btrfs_release_path(path);
+
+ extref = btrfs_lookup_inode_extref(trans, root, path, name,
+ name_len, inode_objectid,
+ ref_objectid, ins_len, cow);
+ if (IS_ERR(extref))
+ return PTR_ERR(extref);
+
+ if (extref) {
+ *ret_index = btrfs_inode_extref_index(path->nodes[0], extref);
+ return 0;
+ }
+
+ return -ENOENT;
+}
+
+int btrfs_del_inode_extref(struct btrfs_trans_handle *trans,
struct btrfs_root *root,
const char *name, int name_len,
u64 inode_objectid, u64 ref_objectid, u64 *index)
{
struct btrfs_path *path;
struct btrfs_key key;
+ struct btrfs_inode_extref *extref;
+ struct extent_buffer *leaf;
+ int ret;
+ int del_len = name_len + sizeof(*extref);
+ unsigned long ptr;
+ unsigned long item_start;
+ u32 item_size;
+
+ key.objectid = inode_objectid;
+ btrfs_set_key_type(&key, BTRFS_INODE_EXTREF_KEY);
+ key.offset = btrfs_extref_hash(ref_objectid, name, name_len);
+
+ path = btrfs_alloc_path();
+ if (!path)
+ return -ENOMEM;
+
+ path->leave_spinning = 1;
+
+ ret = btrfs_search_slot(trans, root, &key, path, -1, 1);
+ if (ret > 0)
+ ret = -ENOENT;
+ if (ret < 0)
+ goto out;
+
+ /*
+ * Sanity check - did we find the right item for this name?
+ * This should always succeed so error here will make the FS
+ * readonly.
+ */
+ if (!btrfs_find_name_in_ext_backref(path, ref_objectid,
+ name, name_len, &extref)) {
+ btrfs_std_error(root->fs_info, -ENOENT);
+ ret = -EROFS;
+ goto out;
+ }
+
+ leaf = path->nodes[0];
+ item_size = btrfs_item_size_nr(leaf, path->slots[0]);
+ if (index)
+ *index = btrfs_inode_extref_index(leaf, extref);
+
+ if (del_len == item_size) {
+ /*
+ * Common case only one ref in the item, remove the
+ * whole item.
+ */
+ ret = btrfs_del_item(trans, root, path);
+ goto out;
+ }
+
+ ptr = (unsigned long)extref;
+ item_start = btrfs_item_ptr_offset(leaf, path->slots[0]);
+
+ memmove_extent_buffer(leaf, ptr, ptr + del_len,
+ item_size - (ptr + del_len - item_start));
+
+ ret = btrfs_truncate_item(trans, root, path, item_size - del_len, 1);
+
+out:
+ btrfs_free_path(path);
+
+ return ret;
+}
+
+int btrfs_del_inode_ref(struct btrfs_trans_handle *trans,
+ struct btrfs_root *root,
+ const char *name, int name_len,
+ u64 inode_objectid, u64 ref_objectid, u64 *index)
+{
+ struct btrfs_path *path;
+ struct btrfs_key key;
struct btrfs_inode_ref *ref;
struct extent_buffer *leaf;
unsigned long ptr;
@@ -90,6 +267,7 @@ int btrfs_del_inode_ref(struct btrfs_trans_handle *trans,
u32 item_size;
u32 sub_item_len;
int ret;
+ int search_ext_refs = 0;
int del_len = name_len + sizeof(*ref);
key.objectid = inode_objectid;
@@ -105,12 +283,14 @@ int btrfs_del_inode_ref(struct btrfs_trans_handle *trans,
ret = btrfs_search_slot(trans, root, &key, path, -1, 1);
if (ret > 0) {
ret = -ENOENT;
+ search_ext_refs = 1;
goto out;
} else if (ret < 0) {
goto out;
}
if (!find_name_in_backref(path, name, name_len, &ref)) {
ret = -ENOENT;
+ search_ext_refs = 1;
goto out;
}
leaf = path->nodes[0];
@@ -132,6 +312,77 @@ int btrfs_del_inode_ref(struct btrfs_trans_handle *trans,
item_size - sub_item_len, 1);
out:
btrfs_free_path(path);
+
+ if (search_ext_refs) {
+ /*
+ * No refs were found, or we could not find the
+ * name in our ref array. Find and remove the extended
+ * inode ref then.
+ */
+ return btrfs_del_inode_extref(trans, root, name, name_len,
+ inode_objectid, ref_objectid, index);
+ }
+
+ return ret;
+}
+
+/*
+ * btrfs_insert_inode_extref() - Inserts an extended inode ref into a tree.
+ *
+ * The caller must have checked against BTRFS_LINK_MAX already.
+ */
+static int btrfs_insert_inode_extref(struct btrfs_trans_handle *trans,
+ struct btrfs_root *root,
+ const char *name, int name_len,
+ u64 inode_objectid, u64 ref_objectid, u64 index)
+{
+ struct btrfs_inode_extref *extref;
+ int ret;
+ int ins_len = name_len + sizeof(*extref);
+ unsigned long ptr;
+ struct btrfs_path *path;
+ struct btrfs_key key;
+ struct extent_buffer *leaf;
+ struct btrfs_item *item;
+
+ key.objectid = inode_objectid;
+ key.type = BTRFS_INODE_EXTREF_KEY;
+ key.offset = btrfs_extref_hash(ref_objectid, name, name_len);
+
+ path = btrfs_alloc_path();
+ if (!path)
+ return -ENOMEM;
+
+ path->leave_spinning = 1;
+ ret = btrfs_insert_empty_item(trans, root, path, &key,
+ ins_len);
+ if (ret == -EEXIST) {
+ if (btrfs_find_name_in_ext_backref(path, ref_objectid,
+ name, name_len, NULL))
+ goto out;
+
+ btrfs_extend_item(trans, root, path, ins_len);
+ ret = 0;
+ }
+ if (ret < 0)
+ goto out;
+
+ leaf = path->nodes[0];
+ item = btrfs_item_nr(leaf, path->slots[0]);
+ ptr = (unsigned long)btrfs_item_ptr(leaf, path->slots[0], char);
+ ptr += btrfs_item_size(leaf, item) - ins_len;
+ extref = (struct btrfs_inode_extref *)ptr;
+
+ btrfs_set_inode_extref_name_len(path->nodes[0], extref, name_len);
+ btrfs_set_inode_extref_index(path->nodes[0], extref, index);
+ btrfs_set_inode_extref_parent(path->nodes[0], extref, ref_objectid);
+
+ ptr = (unsigned long)&extref->name;
+ write_extent_buffer(path->nodes[0], name, ptr, name_len);
+ btrfs_mark_buffer_dirty(path->nodes[0]);
+
+out:
+ btrfs_free_path(path);
return ret;
}
@@ -189,6 +440,19 @@ int btrfs_insert_inode_ref(struct btrfs_trans_handle *trans,
out:
btrfs_free_path(path);
+
+ if (ret == -EMLINK) {
+ struct btrfs_super_block *disk_super = root->fs_info->super_copy;
+ /* We ran out of space in the ref array. Need to
+ * add an extended ref. */
+ if (btrfs_super_incompat_flags(disk_super)
+ & BTRFS_FEATURE_INCOMPAT_EXTENDED_IREF)
+ ret = btrfs_insert_inode_extref(trans, root, name,
+ name_len,
+ inode_objectid,
+ ref_objectid, index);
+ }
+
return ret;
}
diff --git a/fs/btrfs/inode.c b/fs/btrfs/inode.c
index fd1a06df5bc6..56f6e17d46fd 100644
--- a/fs/btrfs/inode.c
+++ b/fs/btrfs/inode.c
@@ -2671,7 +2671,6 @@ static struct btrfs_trans_handle *__unlink_start_trans(struct inode *dir,
struct btrfs_trans_handle *trans;
struct btrfs_root *root = BTRFS_I(dir)->root;
struct btrfs_path *path;
- struct btrfs_inode_ref *ref;
struct btrfs_dir_item *di;
struct inode *inode = dentry->d_inode;
u64 index;
@@ -2785,17 +2784,17 @@ static struct btrfs_trans_handle *__unlink_start_trans(struct inode *dir,
}
btrfs_release_path(path);
- ref = btrfs_lookup_inode_ref(trans, root, path,
- dentry->d_name.name, dentry->d_name.len,
- ino, dir_ino, 0);
- if (IS_ERR(ref)) {
- err = PTR_ERR(ref);
+ ret = btrfs_get_inode_ref_index(trans, root, path, dentry->d_name.name,
+ dentry->d_name.len, ino, dir_ino, 0,
+ &index);
+ if (ret) {
+ err = ret;
goto out;
}
- BUG_ON(!ref);
+
if (check_path_shared(root, path))
goto out;
- index = btrfs_inode_ref_index(path->nodes[0], ref);
+
btrfs_release_path(path);
/*
@@ -4472,6 +4471,12 @@ static struct inode *btrfs_new_inode(struct btrfs_trans_handle *trans,
btrfs_set_key_type(&key[0], BTRFS_INODE_ITEM_KEY);
key[0].offset = 0;
+ /*
+ * Start new inodes with an inode_ref. This is slightly more
+ * efficient for small numbers of hard links since they will
+ * be packed into one item. Extended refs will kick in if we
+ * add more hard links than can fit in the ref item.
+ */
key[1].objectid = objectid;
btrfs_set_key_type(&key[1], BTRFS_INODE_REF_KEY);
key[1].offset = ref_objectid;
@@ -4747,7 +4752,7 @@ static int btrfs_link(struct dentry *old_dentry, struct inode *dir,
if (root->objectid != BTRFS_I(inode)->root->objectid)
return -EXDEV;
- if (inode->i_nlink == ~0U)
+ if (inode->i_nlink >= BTRFS_LINK_MAX)
return -EMLINK;
err = btrfs_set_inode_index(dir, &index);
diff --git a/fs/btrfs/tree-log.c b/fs/btrfs/tree-log.c
index 883cdc1c357b..e0b0d25e557c 100644
--- a/fs/btrfs/tree-log.c
+++ b/fs/btrfs/tree-log.c
@@ -23,8 +23,10 @@
#include "disk-io.h"
#include "locking.h"
#include "print-tree.h"
+#include "backref.h"
#include "compat.h"
#include "tree-log.h"
+#include "hash.h"
/* magic values for the inode_only field in btrfs_log_inode:
*
@@ -746,6 +748,7 @@ out:
*/
static noinline int backref_in_log(struct btrfs_root *log,
struct btrfs_key *key,
+ u64 ref_objectid,
char *name, int namelen)
{
struct btrfs_path *path;
@@ -766,8 +769,17 @@ static noinline int backref_in_log(struct btrfs_root *log,
if (ret != 0)
goto out;
- item_size = btrfs_item_size_nr(path->nodes[0], path->slots[0]);
ptr = btrfs_item_ptr_offset(path->nodes[0], path->slots[0]);
+
+ if (key->type == BTRFS_INODE_EXTREF_KEY) {
+ if (btrfs_find_name_in_ext_backref(path, ref_objectid,
+ name, namelen, NULL))
+ match = 1;
+
+ goto out;
+ }
+
+ item_size = btrfs_item_size_nr(path->nodes[0], path->slots[0]);
ptr_end = ptr + item_size;
while (ptr < ptr_end) {
ref = (struct btrfs_inode_ref *)ptr;
@@ -793,27 +805,36 @@ static inline int __add_inode_ref(struct btrfs_trans_handle *trans,
struct btrfs_path *path,
struct btrfs_root *log_root,
struct inode *dir, struct inode *inode,
- struct btrfs_key *key,
struct extent_buffer *eb,
- struct btrfs_inode_ref *ref,
- char *name, int namelen, int *search_done)
+ u64 inode_objectid, u64 parent_objectid,
+ u64 ref_index, char *name, int namelen,
+ int *search_done)
{
int ret;
+ char *victim_name;
+ int victim_name_len;
+ struct extent_buffer *leaf;
struct btrfs_dir_item *di;
+ struct btrfs_key search_key;
+ struct btrfs_inode_extref *extref;
- ret = btrfs_search_slot(NULL, root, key, path, 0, 0);
+again:
+ /* Search old style refs */
+ search_key.objectid = inode_objectid;
+ search_key.type = BTRFS_INODE_REF_KEY;
+ search_key.offset = parent_objectid;
+ ret = btrfs_search_slot(NULL, root, &search_key, path, 0, 0);
if (ret == 0) {
- char *victim_name;
- int victim_name_len;
struct btrfs_inode_ref *victim_ref;
unsigned long ptr;
unsigned long ptr_end;
- struct extent_buffer *leaf = path->nodes[0];
+
+ leaf = path->nodes[0];
/* are we trying to overwrite a back ref for the root directory
* if so, just jump out, we're done
*/
- if (key->objectid == key->offset)
+ if (search_key.objectid == search_key.offset)
return 1;
/* check all the names in this back reference to see
@@ -833,7 +854,9 @@ static inline int __add_inode_ref(struct btrfs_trans_handle *trans,
(unsigned long)(victim_ref + 1),
victim_name_len);
- if (!backref_in_log(log_root, key, victim_name,
+ if (!backref_in_log(log_root, &search_key,
+ parent_objectid,
+ victim_name,
victim_name_len)) {
btrfs_inc_nlink(inode);
btrfs_release_path(path);
@@ -841,9 +864,14 @@ static inline int __add_inode_ref(struct btrfs_trans_handle *trans,
ret = btrfs_unlink_inode(trans, root, dir,
inode, victim_name,
victim_name_len);
+ BUG_ON(ret);
btrfs_run_delayed_items(trans, root);
+ kfree(victim_name);
+ *search_done = 1;
+ goto again;
}
kfree(victim_name);
+
ptr = (unsigned long)(victim_ref + 1) + victim_name_len;
}
BUG_ON(ret);
@@ -856,10 +884,74 @@ static inline int __add_inode_ref(struct btrfs_trans_handle *trans,
}
btrfs_release_path(path);
+ /* Same search but for extended refs */
+ extref = btrfs_lookup_inode_extref(NULL, root, path, name, namelen,
+ inode_objectid, parent_objectid, 0,
+ 0);
+ if (!IS_ERR_OR_NULL(extref)) {
+ u32 item_size;
+ u32 cur_offset = 0;
+ unsigned long base;
+ struct inode *victim_parent;
+
+ leaf = path->nodes[0];
+
+ item_size = btrfs_item_size_nr(leaf, path->slots[0]);
+ base = btrfs_item_ptr_offset(leaf, path->slots[0]);
+
+ while (cur_offset < item_size) {
+ extref = (struct btrfs_inode_extref *)base + cur_offset;
+
+ victim_name_len = btrfs_inode_extref_name_len(leaf, extref);
+
+ if (btrfs_inode_extref_parent(leaf, extref) != parent_objectid)
+ goto next;
+
+ victim_name = kmalloc(victim_name_len, GFP_NOFS);
+ read_extent_buffer(leaf, victim_name, (unsigned long)&extref->name,
+ victim_name_len);
+
+ search_key.objectid = inode_objectid;
+ search_key.type = BTRFS_INODE_EXTREF_KEY;
+ search_key.offset = btrfs_extref_hash(parent_objectid,
+ victim_name,
+ victim_name_len);
+ ret = 0;
+ if (!backref_in_log(log_root, &search_key,
+ parent_objectid, victim_name,
+ victim_name_len)) {
+ ret = -ENOENT;
+ victim_parent = read_one_inode(root,
+ parent_objectid);
+ if (victim_parent) {
+ btrfs_inc_nlink(inode);
+ btrfs_release_path(path);
+
+ ret = btrfs_unlink_inode(trans, root,
+ victim_parent,
+ inode,
+ victim_name,
+ victim_name_len);
+ btrfs_run_delayed_items(trans, root);
+ }
+ BUG_ON(ret);
+ iput(victim_parent);
+ kfree(victim_name);
+ *search_done = 1;
+ goto again;
+ }
+ kfree(victim_name);
+ BUG_ON(ret);
+next:
+ cur_offset += victim_name_len + sizeof(*extref);
+ }
+ *search_done = 1;
+ }
+ btrfs_release_path(path);
+
/* look for a conflicting sequence number */
di = btrfs_lookup_dir_index_item(trans, root, path, btrfs_ino(dir),
- btrfs_inode_ref_index(eb, ref),
- name, namelen, 0);
+ ref_index, name, namelen, 0);
if (di && !IS_ERR(di)) {
ret = drop_one_dir_item(trans, root, path, dir, di);
BUG_ON(ret);
@@ -878,6 +970,48 @@ static inline int __add_inode_ref(struct btrfs_trans_handle *trans,
return 0;
}
+static int extref_get_fields(struct extent_buffer *eb, unsigned long ref_ptr,
+ u32 *namelen, char **name, u64 *index,
+ u64 *parent_objectid)
+{
+ struct btrfs_inode_extref *extref;
+
+ extref = (struct btrfs_inode_extref *)ref_ptr;
+
+ *namelen = btrfs_inode_extref_name_len(eb, extref);
+ *name = kmalloc(*namelen, GFP_NOFS);
+ if (*name == NULL)
+ return -ENOMEM;
+
+ read_extent_buffer(eb, *name, (unsigned long)&extref->name,
+ *namelen);
+
+ *index = btrfs_inode_extref_index(eb, extref);
+ if (parent_objectid)
+ *parent_objectid = btrfs_inode_extref_parent(eb, extref);
+
+ return 0;
+}
+
+static int ref_get_fields(struct extent_buffer *eb, unsigned long ref_ptr,
+ u32 *namelen, char **name, u64 *index)
+{
+ struct btrfs_inode_ref *ref;
+
+ ref = (struct btrfs_inode_ref *)ref_ptr;
+
+ *namelen = btrfs_inode_ref_name_len(eb, ref);
+ *name = kmalloc(*namelen, GFP_NOFS);
+ if (*name == NULL)
+ return -ENOMEM;
+
+ read_extent_buffer(eb, *name, (unsigned long)(ref + 1), *namelen);
+
+ *index = btrfs_inode_ref_index(eb, ref);
+
+ return 0;
+}
+
/*
* replay one inode back reference item found in the log tree.
* eb, slot and key refer to the buffer and key found in the log tree.
@@ -891,7 +1025,6 @@ static noinline int add_inode_ref(struct btrfs_trans_handle *trans,
struct extent_buffer *eb, int slot,
struct btrfs_key *key)
{
- struct btrfs_inode_ref *ref;
struct inode *dir;
struct inode *inode;
unsigned long ref_ptr;
@@ -900,6 +1033,27 @@ static noinline int add_inode_ref(struct btrfs_trans_handle *trans,
int namelen;
int ret;
int search_done = 0;
+ int log_ref_ver = 0;
+ u64 parent_objectid;
+ u64 inode_objectid;
+ u64 ref_index;
+ int ref_struct_size;
+
+ ref_ptr = btrfs_item_ptr_offset(eb, slot);
+ ref_end = ref_ptr + btrfs_item_size_nr(eb, slot);
+
+ if (key->type == BTRFS_INODE_EXTREF_KEY) {
+ struct btrfs_inode_extref *r;
+
+ ref_struct_size = sizeof(struct btrfs_inode_extref);
+ log_ref_ver = 1;
+ r = (struct btrfs_inode_extref *)ref_ptr;
+ parent_objectid = btrfs_inode_extref_parent(eb, r);
+ } else {
+ ref_struct_size = sizeof(struct btrfs_inode_ref);
+ parent_objectid = key->offset;
+ }
+ inode_objectid = key->objectid;
/*
* it is possible that we didn't log all the parent directories
@@ -907,32 +1061,38 @@ static noinline int add_inode_ref(struct btrfs_trans_handle *trans,
* copy the back ref in. The link count fixup code will take
* care of the rest
*/
- dir = read_one_inode(root, key->offset);
+ dir = read_one_inode(root, parent_objectid);
if (!dir)
return -ENOENT;
- inode = read_one_inode(root, key->objectid);
+ inode = read_one_inode(root, inode_objectid);
if (!inode) {
iput(dir);
return -EIO;
}
- ref_ptr = btrfs_item_ptr_offset(eb, slot);
- ref_end = ref_ptr + btrfs_item_size_nr(eb, slot);
-
while (ref_ptr < ref_end) {
- ref = (struct btrfs_inode_ref *)ref_ptr;
-
- namelen = btrfs_inode_ref_name_len(eb, ref);
- name = kmalloc(namelen, GFP_NOFS);
- BUG_ON(!name);
-
- read_extent_buffer(eb, name, (unsigned long)(ref + 1), namelen);
+ if (log_ref_ver) {
+ ret = extref_get_fields(eb, ref_ptr, &namelen, &name,
+ &ref_index, &parent_objectid);
+ /*
+ * parent object can change from one array
+ * item to another.
+ */
+ if (!dir)
+ dir = read_one_inode(root, parent_objectid);
+ if (!dir)
+ return -ENOENT;
+ } else {
+ ret = ref_get_fields(eb, ref_ptr, &namelen, &name,
+ &ref_index);
+ }
+ if (ret)
+ return ret;
/* if we already have a perfect match, we're done */
if (!inode_in_dir(root, path, btrfs_ino(dir), btrfs_ino(inode),
- btrfs_inode_ref_index(eb, ref),
- name, namelen)) {
+ ref_index, name, namelen)) {
/*
* look for a conflicting back reference in the
* metadata. if we find one we have to unlink that name
@@ -943,8 +1103,10 @@ static noinline int add_inode_ref(struct btrfs_trans_handle *trans,
if (!search_done) {
ret = __add_inode_ref(trans, root, path, log,
- dir, inode, key, eb, ref,
- name, namelen,
+ dir, inode, eb,
+ inode_objectid,
+ parent_objectid,
+ ref_index, name, namelen,
&search_done);
if (ret == 1)
goto out;
@@ -953,14 +1115,18 @@ static noinline int add_inode_ref(struct btrfs_trans_handle *trans,
/* insert our name */
ret = btrfs_add_link(trans, dir, inode, name, namelen,
- 0, btrfs_inode_ref_index(eb, ref));
+ 0, ref_index);
BUG_ON(ret);
btrfs_update_inode(trans, root, inode);
}
- ref_ptr = (unsigned long)(ref + 1) + namelen;
+ ref_ptr = (unsigned long)(ref_ptr + ref_struct_size) + namelen;
kfree(name);
+ if (log_ref_ver) {
+ iput(dir);
+ dir = NULL;
+ }
}
/* finally write the back reference in the inode */
@@ -984,25 +1150,55 @@ static int insert_orphan_item(struct btrfs_trans_handle *trans,
return ret;
}
+static int count_inode_extrefs(struct btrfs_root *root,
+ struct inode *inode, struct btrfs_path *path)
+{
+ int ret = 0;
+ int name_len;
+ unsigned int nlink = 0;
+ u32 item_size;
+ u32 cur_offset = 0;
+ u64 inode_objectid = btrfs_ino(inode);
+ u64 offset = 0;
+ unsigned long ptr;
+ struct btrfs_inode_extref *extref;
+ struct extent_buffer *leaf;
+
+ while (1) {
+ ret = btrfs_find_one_extref(root, inode_objectid, offset, path,
+ &extref, &offset);
+ if (ret)
+ break;
+
+ leaf = path->nodes[0];
+ item_size = btrfs_item_size_nr(leaf, path->slots[0]);
+ ptr = btrfs_item_ptr_offset(leaf, path->slots[0]);
+
+ while (cur_offset < item_size) {
+ extref = (struct btrfs_inode_extref *) (ptr + cur_offset);
+ name_len = btrfs_inode_extref_name_len(leaf, extref);
+
+ nlink++;
+
+ cur_offset += name_len + sizeof(*extref);
+ }
+
+ offset++;
+ btrfs_release_path(path);
+ }
+ btrfs_release_path(path);
+
+ if (ret < 0)
+ return ret;
+ return nlink;
+}
-/*
- * There are a few corners where the link count of the file can't
- * be properly maintained during replay. So, instead of adding
- * lots of complexity to the log code, we just scan the backrefs
- * for any file that has been through replay.
- *
- * The scan will update the link count on the inode to reflect the
- * number of back refs found. If it goes down to zero, the iput
- * will free the inode.
- */
-static noinline int fixup_inode_link_count(struct btrfs_trans_handle *trans,
- struct btrfs_root *root,
- struct inode *inode)
+static int count_inode_refs(struct btrfs_root *root,
+ struct inode *inode, struct btrfs_path *path)
{
- struct btrfs_path *path;
int ret;
struct btrfs_key key;
- u64 nlink = 0;
+ unsigned int nlink = 0;
unsigned long ptr;
unsigned long ptr_end;
int name_len;
@@ -1012,10 +1208,6 @@ static noinline int fixup_inode_link_count(struct btrfs_trans_handle *trans,
key.type = BTRFS_INODE_REF_KEY;
key.offset = (u64)-1;
- path = btrfs_alloc_path();
- if (!path)
- return -ENOMEM;
-
while (1) {
ret = btrfs_search_slot(NULL, root, &key, path, 0, 0);
if (ret < 0)
@@ -1049,6 +1241,50 @@ static noinline int fixup_inode_link_count(struct btrfs_trans_handle *trans,
btrfs_release_path(path);
}
btrfs_release_path(path);
+
+ return nlink;
+}
+
+/*
+ * There are a few corners where the link count of the file can't
+ * be properly maintained during replay. So, instead of adding
+ * lots of complexity to the log code, we just scan the backrefs
+ * for any file that has been through replay.
+ *
+ * The scan will update the link count on the inode to reflect the
+ * number of back refs found. If it goes down to zero, the iput
+ * will free the inode.
+ */
+static noinline int fixup_inode_link_count(struct btrfs_trans_handle *trans,
+ struct btrfs_root *root,
+ struct inode *inode)
+{
+ struct btrfs_path *path;
+ int ret;
+ u64 nlink = 0;
+ u64 ino = btrfs_ino(inode);
+
+ path = btrfs_alloc_path();
+ if (!path)
+ return -ENOMEM;
+
+ ret = count_inode_refs(root, inode, path);
+ if (ret < 0)
+ goto out;
+
+ nlink = ret;
+
+ ret = count_inode_extrefs(root, inode, path);
+ if (ret == -ENOENT)
+ ret = 0;
+
+ if (ret < 0)
+ goto out;
+
+ nlink += ret;
+
+ ret = 0;
+
if (nlink != inode->i_nlink) {
set_nlink(inode, nlink);
btrfs_update_inode(trans, root, inode);
@@ -1064,9 +1300,10 @@ static noinline int fixup_inode_link_count(struct btrfs_trans_handle *trans,
ret = insert_orphan_item(trans, root, ino);
BUG_ON(ret);
}
- btrfs_free_path(path);
- return 0;
+out:
+ btrfs_free_path(path);
+ return ret;
}
static noinline int fixup_inode_link_counts(struct btrfs_trans_handle *trans,
@@ -1711,6 +1948,10 @@ static int replay_one_buffer(struct btrfs_root *log, struct extent_buffer *eb,
ret = add_inode_ref(wc->trans, root, log, path,
eb, i, &key);
BUG_ON(ret && ret != -ENOENT);
+ } else if (key.type == BTRFS_INODE_EXTREF_KEY) {
+ ret = add_inode_ref(wc->trans, root, log, path,
+ eb, i, &key);
+ BUG_ON(ret && ret != -ENOENT);
} else if (key.type == BTRFS_EXTENT_DATA_KEY) {
ret = replay_one_extent(wc->trans, root, path,
eb, i, &key);
--
1.8.0
From: Mark Fasheh <mfasheh@suse.de>
Date: Wed, 8 Aug 2012 11:33:54 -0700
Subject: btrfs: extended inode ref iteration
commit d24bec3ae528a47149b838aad76c006d40fe8a39 upstream.
The iterate_irefs in backref.c is used to build path components from inode
refs. This patch adds code to iterate extended refs as well.
I had modify the callback function signature to abstract out some of the
differences between ref structures. iref_to_path() also needed similar
changes.
Signed-off-by: Mark Fasheh <mfasheh@suse.de>
[jrnieder@gmail.com: backport to 3.2.y; drop iref_to_path() since it
is not used any more]
Signed-off-by: Jonathan Nieder <jrnieder@gmail.com>
---
fs/btrfs/backref.c | 147 +++++++++++++++++++++++++++++++++++++++++------------
fs/btrfs/backref.h | 2 -
2 files changed, 114 insertions(+), 35 deletions(-)
diff --git a/fs/btrfs/backref.c b/fs/btrfs/backref.c
index dd4ac08a3856..e7c8933c0ea4 100644
--- a/fs/btrfs/backref.c
+++ b/fs/btrfs/backref.c
@@ -151,26 +151,12 @@ int btrfs_find_one_extref(struct btrfs_root *root, u64 inode_objectid,
return ret;
}
-/*
- * 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)
+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;
@@ -178,17 +164,17 @@ static char *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);
@@ -196,6 +182,7 @@ static char *iref_to_path(struct btrfs_root *fs_root, struct btrfs_path *path,
ret = inode_ref_info(parent, 0, fs_root, path, &found_key);
if (ret)
break;
+
next_inum = found_key.offset;
/* regular exit ahead */
@@ -211,8 +198,11 @@ static char *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)
@@ -680,9 +670,12 @@ 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;
int slot;
@@ -699,7 +692,7 @@ static int iterate_irefs(u64 inum, struct btrfs_root *fs_root,
while (1) {
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) {
@@ -723,7 +716,8 @@ static int iterate_irefs(u64 inum, struct btrfs_root *fs_root,
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);
+ ret = iterate(parent, name_len,
+ (unsigned long)(iref + 1), eb, ctx);
if (ret) {
free_extent_buffer(eb);
break;
@@ -740,12 +734,98 @@ 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;
@@ -758,8 +838,9 @@ 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 = 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);
@@ -789,7 +870,7 @@ 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);
}
/*
diff --git a/fs/btrfs/backref.h b/fs/btrfs/backref.h
index a81642d33934..58dba365345a 100644
--- a/fs/btrfs/backref.h
+++ b/fs/btrfs/backref.h
@@ -29,8 +29,6 @@ struct inode_fs_paths {
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);
--
1.8.0
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