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Diffstat (limited to 'fs/btrfs/send.c')
-rw-r--r--fs/btrfs/send.c299
1 files changed, 235 insertions, 64 deletions
diff --git a/fs/btrfs/send.c b/fs/btrfs/send.c
index 6ad216e8178e..e258fc484cea 100644
--- a/fs/btrfs/send.c
+++ b/fs/btrfs/send.c
@@ -238,6 +238,7 @@ struct waiting_dir_move {
* after this directory is moved, we can try to rmdir the ino rmdir_ino.
*/
u64 rmdir_ino;
+ u64 rmdir_gen;
bool orphanized;
};
@@ -323,7 +324,7 @@ static int is_waiting_for_move(struct send_ctx *sctx, u64 ino);
static struct waiting_dir_move *
get_waiting_dir_move(struct send_ctx *sctx, u64 ino);
-static int is_waiting_for_rm(struct send_ctx *sctx, u64 dir_ino);
+static int is_waiting_for_rm(struct send_ctx *sctx, u64 dir_ino, u64 gen);
static int need_send_hole(struct send_ctx *sctx)
{
@@ -1257,12 +1258,21 @@ static int __iterate_backrefs(u64 ino, u64 offset, u64 root, void *ctx_)
*/
if (found->root == bctx->sctx->send_root) {
/*
- * TODO for the moment we don't accept clones from the inode
- * that is currently send. We may change this when
- * BTRFS_IOC_CLONE_RANGE supports cloning from and to the same
- * file.
+ * If the source inode was not yet processed we can't issue a
+ * clone operation, as the source extent does not exist yet at
+ * the destination of the stream.
*/
- if (ino >= bctx->cur_objectid)
+ if (ino > bctx->cur_objectid)
+ return 0;
+ /*
+ * We clone from the inode currently being sent as long as the
+ * source extent is already processed, otherwise we could try
+ * to clone from an extent that does not exist yet at the
+ * destination of the stream.
+ */
+ if (ino == bctx->cur_objectid &&
+ offset + bctx->extent_len >
+ bctx->sctx->cur_inode_next_write_offset)
return 0;
}
@@ -2297,7 +2307,7 @@ static int get_cur_path(struct send_ctx *sctx, u64 ino, u64 gen,
fs_path_reset(name);
- if (is_waiting_for_rm(sctx, ino)) {
+ if (is_waiting_for_rm(sctx, ino, gen)) {
ret = gen_unique_name(sctx, ino, gen, name);
if (ret < 0)
goto out;
@@ -2856,8 +2866,8 @@ out:
return ret;
}
-static struct orphan_dir_info *
-add_orphan_dir_info(struct send_ctx *sctx, u64 dir_ino)
+static struct orphan_dir_info *add_orphan_dir_info(struct send_ctx *sctx,
+ u64 dir_ino, u64 dir_gen)
{
struct rb_node **p = &sctx->orphan_dirs.rb_node;
struct rb_node *parent = NULL;
@@ -2866,20 +2876,23 @@ add_orphan_dir_info(struct send_ctx *sctx, u64 dir_ino)
while (*p) {
parent = *p;
entry = rb_entry(parent, struct orphan_dir_info, node);
- if (dir_ino < entry->ino) {
+ if (dir_ino < entry->ino)
p = &(*p)->rb_left;
- } else if (dir_ino > entry->ino) {
+ else if (dir_ino > entry->ino)
p = &(*p)->rb_right;
- } else {
+ else if (dir_gen < entry->gen)
+ p = &(*p)->rb_left;
+ else if (dir_gen > entry->gen)
+ p = &(*p)->rb_right;
+ else
return entry;
- }
}
odi = kmalloc(sizeof(*odi), GFP_KERNEL);
if (!odi)
return ERR_PTR(-ENOMEM);
odi->ino = dir_ino;
- odi->gen = 0;
+ odi->gen = dir_gen;
odi->last_dir_index_offset = 0;
rb_link_node(&odi->node, parent, p);
@@ -2887,8 +2900,8 @@ add_orphan_dir_info(struct send_ctx *sctx, u64 dir_ino)
return odi;
}
-static struct orphan_dir_info *
-get_orphan_dir_info(struct send_ctx *sctx, u64 dir_ino)
+static struct orphan_dir_info *get_orphan_dir_info(struct send_ctx *sctx,
+ u64 dir_ino, u64 gen)
{
struct rb_node *n = sctx->orphan_dirs.rb_node;
struct orphan_dir_info *entry;
@@ -2899,15 +2912,19 @@ get_orphan_dir_info(struct send_ctx *sctx, u64 dir_ino)
n = n->rb_left;
else if (dir_ino > entry->ino)
n = n->rb_right;
+ else if (gen < entry->gen)
+ n = n->rb_left;
+ else if (gen > entry->gen)
+ n = n->rb_right;
else
return entry;
}
return NULL;
}
-static int is_waiting_for_rm(struct send_ctx *sctx, u64 dir_ino)
+static int is_waiting_for_rm(struct send_ctx *sctx, u64 dir_ino, u64 gen)
{
- struct orphan_dir_info *odi = get_orphan_dir_info(sctx, dir_ino);
+ struct orphan_dir_info *odi = get_orphan_dir_info(sctx, dir_ino, gen);
return odi != NULL;
}
@@ -2952,7 +2969,7 @@ static int can_rmdir(struct send_ctx *sctx, u64 dir, u64 dir_gen,
key.type = BTRFS_DIR_INDEX_KEY;
key.offset = 0;
- odi = get_orphan_dir_info(sctx, dir);
+ odi = get_orphan_dir_info(sctx, dir, dir_gen);
if (odi)
key.offset = odi->last_dir_index_offset;
@@ -2983,7 +3000,7 @@ static int can_rmdir(struct send_ctx *sctx, u64 dir, u64 dir_gen,
dm = get_waiting_dir_move(sctx, loc.objectid);
if (dm) {
- odi = add_orphan_dir_info(sctx, dir);
+ odi = add_orphan_dir_info(sctx, dir, dir_gen);
if (IS_ERR(odi)) {
ret = PTR_ERR(odi);
goto out;
@@ -2991,12 +3008,13 @@ static int can_rmdir(struct send_ctx *sctx, u64 dir, u64 dir_gen,
odi->gen = dir_gen;
odi->last_dir_index_offset = found_key.offset;
dm->rmdir_ino = dir;
+ dm->rmdir_gen = dir_gen;
ret = 0;
goto out;
}
if (loc.objectid > send_progress) {
- odi = add_orphan_dir_info(sctx, dir);
+ odi = add_orphan_dir_info(sctx, dir, dir_gen);
if (IS_ERR(odi)) {
ret = PTR_ERR(odi);
goto out;
@@ -3036,6 +3054,7 @@ static int add_waiting_dir_move(struct send_ctx *sctx, u64 ino, bool orphanized)
return -ENOMEM;
dm->ino = ino;
dm->rmdir_ino = 0;
+ dm->rmdir_gen = 0;
dm->orphanized = orphanized;
while (*p) {
@@ -3181,7 +3200,7 @@ static int path_loop(struct send_ctx *sctx, struct fs_path *name,
while (ino != BTRFS_FIRST_FREE_OBJECTID) {
fs_path_reset(name);
- if (is_waiting_for_rm(sctx, ino))
+ if (is_waiting_for_rm(sctx, ino, gen))
break;
if (is_waiting_for_move(sctx, ino)) {
if (*ancestor_ino == 0)
@@ -3221,6 +3240,7 @@ static int apply_dir_move(struct send_ctx *sctx, struct pending_dir_move *pm)
u64 parent_ino, parent_gen;
struct waiting_dir_move *dm = NULL;
u64 rmdir_ino = 0;
+ u64 rmdir_gen;
u64 ancestor;
bool is_orphan;
int ret;
@@ -3235,6 +3255,7 @@ static int apply_dir_move(struct send_ctx *sctx, struct pending_dir_move *pm)
dm = get_waiting_dir_move(sctx, pm->ino);
ASSERT(dm);
rmdir_ino = dm->rmdir_ino;
+ rmdir_gen = dm->rmdir_gen;
is_orphan = dm->orphanized;
free_waiting_dir_move(sctx, dm);
@@ -3271,6 +3292,7 @@ static int apply_dir_move(struct send_ctx *sctx, struct pending_dir_move *pm)
dm = get_waiting_dir_move(sctx, pm->ino);
ASSERT(dm);
dm->rmdir_ino = rmdir_ino;
+ dm->rmdir_gen = rmdir_gen;
}
goto out;
}
@@ -3289,7 +3311,7 @@ static int apply_dir_move(struct send_ctx *sctx, struct pending_dir_move *pm)
struct orphan_dir_info *odi;
u64 gen;
- odi = get_orphan_dir_info(sctx, rmdir_ino);
+ odi = get_orphan_dir_info(sctx, rmdir_ino, rmdir_gen);
if (!odi) {
/* already deleted */
goto finish;
@@ -3804,6 +3826,72 @@ static int update_ref_path(struct send_ctx *sctx, struct recorded_ref *ref)
}
/*
+ * When processing the new references for an inode we may orphanize an existing
+ * directory inode because its old name conflicts with one of the new references
+ * of the current inode. Later, when processing another new reference of our
+ * inode, we might need to orphanize another inode, but the path we have in the
+ * reference reflects the pre-orphanization name of the directory we previously
+ * orphanized. For example:
+ *
+ * parent snapshot looks like:
+ *
+ * . (ino 256)
+ * |----- f1 (ino 257)
+ * |----- f2 (ino 258)
+ * |----- d1/ (ino 259)
+ * |----- d2/ (ino 260)
+ *
+ * send snapshot looks like:
+ *
+ * . (ino 256)
+ * |----- d1 (ino 258)
+ * |----- f2/ (ino 259)
+ * |----- f2_link/ (ino 260)
+ * | |----- f1 (ino 257)
+ * |
+ * |----- d2 (ino 258)
+ *
+ * When processing inode 257 we compute the name for inode 259 as "d1", and we
+ * cache it in the name cache. Later when we start processing inode 258, when
+ * collecting all its new references we set a full path of "d1/d2" for its new
+ * reference with name "d2". When we start processing the new references we
+ * start by processing the new reference with name "d1", and this results in
+ * orphanizing inode 259, since its old reference causes a conflict. Then we
+ * move on the next new reference, with name "d2", and we find out we must
+ * orphanize inode 260, as its old reference conflicts with ours - but for the
+ * orphanization we use a source path corresponding to the path we stored in the
+ * new reference, which is "d1/d2" and not "o259-6-0/d2" - this makes the
+ * receiver fail since the path component "d1/" no longer exists, it was renamed
+ * to "o259-6-0/" when processing the previous new reference. So in this case we
+ * must recompute the path in the new reference and use it for the new
+ * orphanization operation.
+ */
+static int refresh_ref_path(struct send_ctx *sctx, struct recorded_ref *ref)
+{
+ char *name;
+ int ret;
+
+ name = kmemdup(ref->name, ref->name_len, GFP_KERNEL);
+ if (!name)
+ return -ENOMEM;
+
+ fs_path_reset(ref->full_path);
+ ret = get_cur_path(sctx, ref->dir, ref->dir_gen, ref->full_path);
+ if (ret < 0)
+ goto out;
+
+ ret = fs_path_add(ref->full_path, name, ref->name_len);
+ if (ret < 0)
+ goto out;
+
+ /* Update the reference's base name pointer. */
+ set_ref_path(ref, ref->full_path);
+out:
+ kfree(name);
+ return ret;
+}
+
+/*
* This does all the move/link/unlink/rmdir magic.
*/
static int process_recorded_refs(struct send_ctx *sctx, int *pending_move)
@@ -3871,52 +3959,56 @@ static int process_recorded_refs(struct send_ctx *sctx, int *pending_move)
goto out;
}
+ /*
+ * Before doing any rename and link operations, do a first pass on the
+ * new references to orphanize any unprocessed inodes that may have a
+ * reference that conflicts with one of the new references of the current
+ * inode. This needs to happen first because a new reference may conflict
+ * with the old reference of a parent directory, so we must make sure
+ * that the path used for link and rename commands don't use an
+ * orphanized name when an ancestor was not yet orphanized.
+ *
+ * Example:
+ *
+ * Parent snapshot:
+ *
+ * . (ino 256)
+ * |----- testdir/ (ino 259)
+ * | |----- a (ino 257)
+ * |
+ * |----- b (ino 258)
+ *
+ * Send snapshot:
+ *
+ * . (ino 256)
+ * |----- testdir_2/ (ino 259)
+ * | |----- a (ino 260)
+ * |
+ * |----- testdir (ino 257)
+ * |----- b (ino 257)
+ * |----- b2 (ino 258)
+ *
+ * Processing the new reference for inode 257 with name "b" may happen
+ * before processing the new reference with name "testdir". If so, we
+ * must make sure that by the time we send a link command to create the
+ * hard link "b", inode 259 was already orphanized, since the generated
+ * path in "valid_path" already contains the orphanized name for 259.
+ * We are processing inode 257, so only later when processing 259 we do
+ * the rename operation to change its temporary (orphanized) name to
+ * "testdir_2".
+ */
list_for_each_entry(cur, &sctx->new_refs, list) {
- /*
- * We may have refs where the parent directory does not exist
- * yet. This happens if the parent directories inum is higher
- * than the current inum. To handle this case, we create the
- * parent directory out of order. But we need to check if this
- * did already happen before due to other refs in the same dir.
- */
ret = get_cur_inode_state(sctx, cur->dir, cur->dir_gen);
if (ret < 0)
goto out;
- if (ret == inode_state_will_create) {
- ret = 0;
- /*
- * First check if any of the current inodes refs did
- * already create the dir.
- */
- list_for_each_entry(cur2, &sctx->new_refs, list) {
- if (cur == cur2)
- break;
- if (cur2->dir == cur->dir) {
- ret = 1;
- break;
- }
- }
-
- /*
- * If that did not happen, check if a previous inode
- * did already create the dir.
- */
- if (!ret)
- ret = did_create_dir(sctx, cur->dir);
- if (ret < 0)
- goto out;
- if (!ret) {
- ret = send_create_inode(sctx, cur->dir);
- if (ret < 0)
- goto out;
- }
- }
+ if (ret == inode_state_will_create)
+ continue;
/*
- * Check if this new ref would overwrite the first ref of
- * another unprocessed inode. If yes, orphanize the
- * overwritten inode. If we find an overwritten ref that is
- * not the first ref, simply unlink it.
+ * Check if this new ref would overwrite the first ref of another
+ * unprocessed inode. If yes, orphanize the overwritten inode.
+ * If we find an overwritten ref that is not the first ref,
+ * simply unlink it.
*/
ret = will_overwrite_ref(sctx, cur->dir, cur->dir_gen,
cur->name, cur->name_len,
@@ -3933,6 +4025,12 @@ static int process_recorded_refs(struct send_ctx *sctx, int *pending_move)
struct name_cache_entry *nce;
struct waiting_dir_move *wdm;
+ if (orphanized_dir) {
+ ret = refresh_ref_path(sctx, cur);
+ if (ret < 0)
+ goto out;
+ }
+
ret = orphanize_inode(sctx, ow_inode, ow_gen,
cur->full_path);
if (ret < 0)
@@ -3989,12 +4087,66 @@ static int process_recorded_refs(struct send_ctx *sctx, int *pending_move)
if (ret < 0)
goto out;
} else {
+ /*
+ * If we previously orphanized a directory that
+ * collided with a new reference that we already
+ * processed, recompute the current path because
+ * that directory may be part of the path.
+ */
+ if (orphanized_dir) {
+ ret = refresh_ref_path(sctx, cur);
+ if (ret < 0)
+ goto out;
+ }
ret = send_unlink(sctx, cur->full_path);
if (ret < 0)
goto out;
}
}
+ }
+
+ list_for_each_entry(cur, &sctx->new_refs, list) {
+ /*
+ * We may have refs where the parent directory does not exist
+ * yet. This happens if the parent directories inum is higher
+ * than the current inum. To handle this case, we create the
+ * parent directory out of order. But we need to check if this
+ * did already happen before due to other refs in the same dir.
+ */
+ ret = get_cur_inode_state(sctx, cur->dir, cur->dir_gen);
+ if (ret < 0)
+ goto out;
+ if (ret == inode_state_will_create) {
+ ret = 0;
+ /*
+ * First check if any of the current inodes refs did
+ * already create the dir.
+ */
+ list_for_each_entry(cur2, &sctx->new_refs, list) {
+ if (cur == cur2)
+ break;
+ if (cur2->dir == cur->dir) {
+ ret = 1;
+ break;
+ }
+ }
+
+ /*
+ * If that did not happen, check if a previous inode
+ * did already create the dir.
+ */
+ if (!ret)
+ ret = did_create_dir(sctx, cur->dir);
+ if (ret < 0)
+ goto out;
+ if (!ret) {
+ ret = send_create_inode(sctx, cur->dir);
+ if (ret < 0)
+ goto out;
+ }
+ }
+
if (S_ISDIR(sctx->cur_inode_mode) && sctx->parent_root) {
ret = wait_for_dest_dir_move(sctx, cur, is_orphan);
if (ret < 0)
@@ -4853,6 +5005,10 @@ static ssize_t fill_read_buf(struct send_ctx *sctx, u64 offset, u32 len)
lock_page(page);
if (!PageUptodate(page)) {
unlock_page(page);
+ btrfs_err(fs_info,
+ "send: IO error at offset %llu for inode %llu root %llu",
+ page_offset(page), sctx->cur_ino,
+ sctx->send_root->root_key.objectid);
put_page(page);
ret = -EIO;
break;
@@ -5378,6 +5534,21 @@ static int clone_range(struct send_ctx *sctx,
break;
offset += clone_len;
clone_root->offset += clone_len;
+
+ /*
+ * If we are cloning from the file we are currently processing,
+ * and using the send root as the clone root, we must stop once
+ * the current clone offset reaches the current eof of the file
+ * at the receiver, otherwise we would issue an invalid clone
+ * operation (source range going beyond eof) and cause the
+ * receiver to fail. So if we reach the current eof, bail out
+ * and fallback to a regular write.
+ */
+ if (clone_root->root == sctx->send_root &&
+ clone_root->ino == sctx->cur_ino &&
+ clone_root->offset >= sctx->cur_inode_next_write_offset)
+ break;
+
data_offset += clone_len;
next:
path->slots[0]++;
@@ -7224,7 +7395,7 @@ long btrfs_ioctl_send(struct file *mnt_file, struct btrfs_ioctl_send_args *arg)
alloc_size = sizeof(struct clone_root) * (arg->clone_sources_count + 1);
- sctx->clone_roots = kzalloc(alloc_size, GFP_KERNEL);
+ sctx->clone_roots = kvzalloc(alloc_size, GFP_KERNEL);
if (!sctx->clone_roots) {
ret = -ENOMEM;
goto out;
Copyright © 1996 – 2023 Jason A. Donenfeld. All Rights Reverse Engineered.