Update Linux to v5.4.2
Change-Id: Idf6911045d9d382da2cfe01b1edff026404ac8fd
diff --git a/fs/btrfs/send.c b/fs/btrfs/send.c
index 84cb6e5..123ac54 100644
--- a/fs/btrfs/send.c
+++ b/fs/btrfs/send.c
@@ -260,6 +260,21 @@
char name[];
};
+#define ADVANCE 1
+#define ADVANCE_ONLY_NEXT -1
+
+enum btrfs_compare_tree_result {
+ BTRFS_COMPARE_TREE_NEW,
+ BTRFS_COMPARE_TREE_DELETED,
+ BTRFS_COMPARE_TREE_CHANGED,
+ BTRFS_COMPARE_TREE_SAME,
+};
+typedef int (*btrfs_changed_cb_t)(struct btrfs_path *left_path,
+ struct btrfs_path *right_path,
+ struct btrfs_key *key,
+ enum btrfs_compare_tree_result result,
+ void *ctx);
+
__cold
static void inconsistent_snapshot_error(struct send_ctx *sctx,
enum btrfs_compare_tree_result result,
@@ -686,7 +701,7 @@
hdr->len = cpu_to_le32(sctx->send_size - sizeof(*hdr));
hdr->crc = 0;
- crc = crc32c(0, (unsigned char *)sctx->send_buf, sctx->send_size);
+ crc = btrfs_crc32c(0, (unsigned char *)sctx->send_buf, sctx->send_size);
hdr->crc = cpu_to_le32(crc);
ret = write_buf(sctx->send_filp, sctx->send_buf, sctx->send_size,
@@ -1160,7 +1175,6 @@
struct backref_ctx {
struct send_ctx *sctx;
- struct btrfs_path *path;
/* number of total found references */
u64 found;
@@ -1186,9 +1200,9 @@
u64 root = (u64)(uintptr_t)key;
struct clone_root *cr = (struct clone_root *)elt;
- if (root < cr->root->objectid)
+ if (root < cr->root->root_key.objectid)
return -1;
- if (root > cr->root->objectid)
+ if (root > cr->root->root_key.objectid)
return 1;
return 0;
}
@@ -1198,9 +1212,9 @@
struct clone_root *cr1 = (struct clone_root *)e1;
struct clone_root *cr2 = (struct clone_root *)e2;
- if (cr1->root->objectid < cr2->root->objectid)
+ if (cr1->root->root_key.objectid < cr2->root->root_key.objectid)
return -1;
- if (cr1->root->objectid > cr2->root->objectid)
+ if (cr1->root->root_key.objectid > cr2->root->root_key.objectid)
return 1;
return 0;
}
@@ -1213,8 +1227,6 @@
{
struct backref_ctx *bctx = ctx_;
struct clone_root *found;
- int ret;
- u64 i_size;
/* First check if the root is in the list of accepted clone sources */
found = bsearch((void *)(uintptr_t)root, bctx->sctx->clone_roots,
@@ -1231,19 +1243,6 @@
}
/*
- * There are inodes that have extents that lie behind its i_size. Don't
- * accept clones from these extents.
- */
- ret = __get_inode_info(found->root, bctx->path, ino, &i_size, NULL, NULL,
- NULL, NULL, NULL);
- btrfs_release_path(bctx->path);
- if (ret < 0)
- return ret;
-
- if (offset + bctx->data_offset + bctx->extent_len > i_size)
- return 0;
-
- /*
* Make sure we don't consider clones from send_root that are
* behind the current inode/offset.
*/
@@ -1319,8 +1318,6 @@
goto out;
}
- backref_ctx->path = tmp_path;
-
if (data_offset >= ino_size) {
/*
* There may be extents that lie behind the file's size.
@@ -1693,12 +1690,8 @@
di = btrfs_lookup_dir_item(NULL, root, path,
dir, name, name_len, 0);
- if (!di) {
- ret = -ENOENT;
- goto out;
- }
- if (IS_ERR(di)) {
- ret = PTR_ERR(di);
+ if (IS_ERR_OR_NULL(di)) {
+ ret = di ? PTR_ERR(di) : -ENOENT;
goto out;
}
btrfs_dir_item_key_to_cpu(path->nodes[0], di, &key);
@@ -2242,7 +2235,7 @@
* inodes "orphan" name instead of the real name and stop. Same with new inodes
* that were not created yet and overwritten inodes/refs.
*
- * When do we have have orphan inodes:
+ * When do we have orphan inodes:
* 1. When an inode is freshly created and thus no valid refs are available yet
* 2. When a directory lost all it's refs (deleted) but still has dir items
* inside which were not processed yet (pending for move/delete). If anyone
@@ -2346,7 +2339,7 @@
return -ENOMEM;
}
- key.objectid = send_root->objectid;
+ key.objectid = send_root->root_key.objectid;
key.type = BTRFS_ROOT_BACKREF_KEY;
key.offset = 0;
@@ -2362,7 +2355,7 @@
leaf = path->nodes[0];
btrfs_item_key_to_cpu(leaf, &key, path->slots[0]);
if (key.type != BTRFS_ROOT_BACKREF_KEY ||
- key.objectid != send_root->objectid) {
+ key.objectid != send_root->root_key.objectid) {
ret = -ENOENT;
goto out;
}
@@ -3858,7 +3851,7 @@
/*
* We may have refs where the parent directory does not exist
* yet. This happens if the parent directories inum is higher
- * the the current inum. To handle this case, we create the
+ * 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.
*/
@@ -4779,7 +4772,7 @@
struct btrfs_key key;
pgoff_t index = offset >> PAGE_SHIFT;
pgoff_t last_index;
- unsigned pg_offset = offset & ~PAGE_MASK;
+ unsigned pg_offset = offset_in_page(offset);
ssize_t ret = 0;
key.objectid = sctx->cur_ino;
@@ -4912,8 +4905,8 @@
btrfs_debug(sctx->send_root->fs_info,
"send_clone offset=%llu, len=%d, clone_root=%llu, clone_inode=%llu, clone_offset=%llu",
- offset, len, clone_root->root->objectid, clone_root->ino,
- clone_root->offset);
+ offset, len, clone_root->root->root_key.objectid,
+ clone_root->ino, clone_root->offset);
p = fs_path_alloc();
if (!p)
@@ -5021,6 +5014,12 @@
if (offset >= sctx->cur_inode_size)
return 0;
+ /*
+ * Don't go beyond the inode's i_size due to prealloc extents that start
+ * after the i_size.
+ */
+ end = min_t(u64, end, sctx->cur_inode_size);
+
if (sctx->flags & BTRFS_SEND_FLAG_NO_FILE_DATA)
return send_update_extent(sctx, offset, end - offset);
@@ -5086,6 +5085,7 @@
struct btrfs_path *path;
struct btrfs_key key;
int ret;
+ u64 clone_src_i_size = 0;
/*
* Prevent cloning from a zero offset with a length matching the sector
@@ -5111,6 +5111,16 @@
return -ENOMEM;
/*
+ * There are inodes that have extents that lie behind its i_size. Don't
+ * accept clones from these extents.
+ */
+ ret = __get_inode_info(clone_root->root, path, clone_root->ino,
+ &clone_src_i_size, NULL, NULL, NULL, NULL, NULL);
+ btrfs_release_path(path);
+ if (ret < 0)
+ goto out;
+
+ /*
* We can't send a clone operation for the entire range if we find
* extent items in the respective range in the source file that
* refer to different extents or if we find holes.
@@ -5152,6 +5162,7 @@
u8 type;
u64 ext_len;
u64 clone_len;
+ u64 clone_data_offset;
if (slot >= btrfs_header_nritems(leaf)) {
ret = btrfs_next_leaf(clone_root->root, path);
@@ -5205,13 +5216,73 @@
if (key.offset >= clone_root->offset + len)
break;
+ if (key.offset >= clone_src_i_size)
+ break;
+
+ if (key.offset + ext_len > clone_src_i_size)
+ ext_len = clone_src_i_size - key.offset;
+
+ clone_data_offset = btrfs_file_extent_offset(leaf, ei);
+ if (btrfs_file_extent_disk_bytenr(leaf, ei) == disk_byte) {
+ clone_root->offset = key.offset;
+ if (clone_data_offset < data_offset &&
+ clone_data_offset + ext_len > data_offset) {
+ u64 extent_offset;
+
+ extent_offset = data_offset - clone_data_offset;
+ ext_len -= extent_offset;
+ clone_data_offset += extent_offset;
+ clone_root->offset += extent_offset;
+ }
+ }
+
clone_len = min_t(u64, ext_len, len);
if (btrfs_file_extent_disk_bytenr(leaf, ei) == disk_byte &&
- btrfs_file_extent_offset(leaf, ei) == data_offset)
- ret = send_clone(sctx, offset, clone_len, clone_root);
- else
+ clone_data_offset == data_offset) {
+ const u64 src_end = clone_root->offset + clone_len;
+ const u64 sectorsize = SZ_64K;
+
+ /*
+ * We can't clone the last block, when its size is not
+ * sector size aligned, into the middle of a file. If we
+ * do so, the receiver will get a failure (-EINVAL) when
+ * trying to clone or will silently corrupt the data in
+ * the destination file if it's on a kernel without the
+ * fix introduced by commit ac765f83f1397646
+ * ("Btrfs: fix data corruption due to cloning of eof
+ * block).
+ *
+ * So issue a clone of the aligned down range plus a
+ * regular write for the eof block, if we hit that case.
+ *
+ * Also, we use the maximum possible sector size, 64K,
+ * because we don't know what's the sector size of the
+ * filesystem that receives the stream, so we have to
+ * assume the largest possible sector size.
+ */
+ if (src_end == clone_src_i_size &&
+ !IS_ALIGNED(src_end, sectorsize) &&
+ offset + clone_len < sctx->cur_inode_size) {
+ u64 slen;
+
+ slen = ALIGN_DOWN(src_end - clone_root->offset,
+ sectorsize);
+ if (slen > 0) {
+ ret = send_clone(sctx, offset, slen,
+ clone_root);
+ if (ret < 0)
+ goto out;
+ }
+ ret = send_extent_data(sctx, offset + slen,
+ clone_len - slen);
+ } else {
+ ret = send_clone(sctx, offset, clone_len,
+ clone_root);
+ }
+ } else {
ret = send_extent_data(sctx, offset, clone_len);
+ }
if (ret < 0)
goto out;
@@ -6266,68 +6337,21 @@
{
int ret = 0;
- if (sctx->cur_ino != sctx->cmp_key->objectid) {
-
- if (result == BTRFS_COMPARE_TREE_CHANGED) {
- struct extent_buffer *leaf_l;
- struct extent_buffer *leaf_r;
- struct btrfs_file_extent_item *ei_l;
- struct btrfs_file_extent_item *ei_r;
-
- leaf_l = sctx->left_path->nodes[0];
- leaf_r = sctx->right_path->nodes[0];
- ei_l = btrfs_item_ptr(leaf_l,
- sctx->left_path->slots[0],
- struct btrfs_file_extent_item);
- ei_r = btrfs_item_ptr(leaf_r,
- sctx->right_path->slots[0],
- struct btrfs_file_extent_item);
-
- /*
- * We may have found an extent item that has changed
- * only its disk_bytenr field and the corresponding
- * inode item was not updated. This case happens due to
- * very specific timings during relocation when a leaf
- * that contains file extent items is COWed while
- * relocation is ongoing and its in the stage where it
- * updates data pointers. So when this happens we can
- * safely ignore it since we know it's the same extent,
- * but just at different logical and physical locations
- * (when an extent is fully replaced with a new one, we
- * know the generation number must have changed too,
- * since snapshot creation implies committing the current
- * transaction, and the inode item must have been updated
- * as well).
- * This replacement of the disk_bytenr happens at
- * relocation.c:replace_file_extents() through
- * relocation.c:btrfs_reloc_cow_block().
- */
- if (btrfs_file_extent_generation(leaf_l, ei_l) ==
- btrfs_file_extent_generation(leaf_r, ei_r) &&
- btrfs_file_extent_ram_bytes(leaf_l, ei_l) ==
- btrfs_file_extent_ram_bytes(leaf_r, ei_r) &&
- btrfs_file_extent_compression(leaf_l, ei_l) ==
- btrfs_file_extent_compression(leaf_r, ei_r) &&
- btrfs_file_extent_encryption(leaf_l, ei_l) ==
- btrfs_file_extent_encryption(leaf_r, ei_r) &&
- btrfs_file_extent_other_encoding(leaf_l, ei_l) ==
- btrfs_file_extent_other_encoding(leaf_r, ei_r) &&
- btrfs_file_extent_type(leaf_l, ei_l) ==
- btrfs_file_extent_type(leaf_r, ei_r) &&
- btrfs_file_extent_disk_bytenr(leaf_l, ei_l) !=
- btrfs_file_extent_disk_bytenr(leaf_r, ei_r) &&
- btrfs_file_extent_disk_num_bytes(leaf_l, ei_l) ==
- btrfs_file_extent_disk_num_bytes(leaf_r, ei_r) &&
- btrfs_file_extent_offset(leaf_l, ei_l) ==
- btrfs_file_extent_offset(leaf_r, ei_r) &&
- btrfs_file_extent_num_bytes(leaf_l, ei_l) ==
- btrfs_file_extent_num_bytes(leaf_r, ei_r))
- return 0;
- }
-
- inconsistent_snapshot_error(sctx, result, "extent");
- return -EIO;
- }
+ /*
+ * We have found an extent item that changed without the inode item
+ * having changed. This can happen either after relocation (where the
+ * disk_bytenr of an extent item is replaced at
+ * relocation.c:replace_file_extents()) or after deduplication into a
+ * file in both the parent and send snapshots (where an extent item can
+ * get modified or replaced with a new one). Note that deduplication
+ * updates the inode item, but it only changes the iversion (sequence
+ * field in the inode item) of the inode, so if a file is deduplicated
+ * the same amount of times in both the parent and send snapshots, its
+ * iversion becames the same in both snapshots, whence the inode item is
+ * the same on both snapshots.
+ */
+ if (sctx->cur_ino != sctx->cmp_key->objectid)
+ return 0;
if (!sctx->cur_inode_new_gen && !sctx->cur_inode_deleted) {
if (result != BTRFS_COMPARE_TREE_DELETED)
@@ -6505,6 +6529,366 @@
return ret;
}
+static int tree_move_down(struct btrfs_path *path, int *level)
+{
+ struct extent_buffer *eb;
+
+ BUG_ON(*level == 0);
+ eb = btrfs_read_node_slot(path->nodes[*level], path->slots[*level]);
+ if (IS_ERR(eb))
+ return PTR_ERR(eb);
+
+ path->nodes[*level - 1] = eb;
+ path->slots[*level - 1] = 0;
+ (*level)--;
+ return 0;
+}
+
+static int tree_move_next_or_upnext(struct btrfs_path *path,
+ int *level, int root_level)
+{
+ int ret = 0;
+ int nritems;
+ nritems = btrfs_header_nritems(path->nodes[*level]);
+
+ path->slots[*level]++;
+
+ while (path->slots[*level] >= nritems) {
+ if (*level == root_level)
+ return -1;
+
+ /* move upnext */
+ path->slots[*level] = 0;
+ free_extent_buffer(path->nodes[*level]);
+ path->nodes[*level] = NULL;
+ (*level)++;
+ path->slots[*level]++;
+
+ nritems = btrfs_header_nritems(path->nodes[*level]);
+ ret = 1;
+ }
+ return ret;
+}
+
+/*
+ * Returns 1 if it had to move up and next. 0 is returned if it moved only next
+ * or down.
+ */
+static int tree_advance(struct btrfs_path *path,
+ int *level, int root_level,
+ int allow_down,
+ struct btrfs_key *key)
+{
+ int ret;
+
+ if (*level == 0 || !allow_down) {
+ ret = tree_move_next_or_upnext(path, level, root_level);
+ } else {
+ ret = tree_move_down(path, level);
+ }
+ if (ret >= 0) {
+ if (*level == 0)
+ btrfs_item_key_to_cpu(path->nodes[*level], key,
+ path->slots[*level]);
+ else
+ btrfs_node_key_to_cpu(path->nodes[*level], key,
+ path->slots[*level]);
+ }
+ return ret;
+}
+
+static int tree_compare_item(struct btrfs_path *left_path,
+ struct btrfs_path *right_path,
+ char *tmp_buf)
+{
+ int cmp;
+ int len1, len2;
+ unsigned long off1, off2;
+
+ len1 = btrfs_item_size_nr(left_path->nodes[0], left_path->slots[0]);
+ len2 = btrfs_item_size_nr(right_path->nodes[0], right_path->slots[0]);
+ if (len1 != len2)
+ return 1;
+
+ off1 = btrfs_item_ptr_offset(left_path->nodes[0], left_path->slots[0]);
+ off2 = btrfs_item_ptr_offset(right_path->nodes[0],
+ right_path->slots[0]);
+
+ read_extent_buffer(left_path->nodes[0], tmp_buf, off1, len1);
+
+ cmp = memcmp_extent_buffer(right_path->nodes[0], tmp_buf, off2, len1);
+ if (cmp)
+ return 1;
+ return 0;
+}
+
+/*
+ * This function compares two trees and calls the provided callback for
+ * every changed/new/deleted item it finds.
+ * If shared tree blocks are encountered, whole subtrees are skipped, making
+ * the compare pretty fast on snapshotted subvolumes.
+ *
+ * This currently works on commit roots only. As commit roots are read only,
+ * we don't do any locking. The commit roots are protected with transactions.
+ * Transactions are ended and rejoined when a commit is tried in between.
+ *
+ * This function checks for modifications done to the trees while comparing.
+ * If it detects a change, it aborts immediately.
+ */
+static int btrfs_compare_trees(struct btrfs_root *left_root,
+ struct btrfs_root *right_root,
+ btrfs_changed_cb_t changed_cb, void *ctx)
+{
+ struct btrfs_fs_info *fs_info = left_root->fs_info;
+ int ret;
+ int cmp;
+ struct btrfs_path *left_path = NULL;
+ struct btrfs_path *right_path = NULL;
+ struct btrfs_key left_key;
+ struct btrfs_key right_key;
+ char *tmp_buf = NULL;
+ int left_root_level;
+ int right_root_level;
+ int left_level;
+ int right_level;
+ int left_end_reached;
+ int right_end_reached;
+ int advance_left;
+ int advance_right;
+ u64 left_blockptr;
+ u64 right_blockptr;
+ u64 left_gen;
+ u64 right_gen;
+
+ left_path = btrfs_alloc_path();
+ if (!left_path) {
+ ret = -ENOMEM;
+ goto out;
+ }
+ right_path = btrfs_alloc_path();
+ if (!right_path) {
+ ret = -ENOMEM;
+ goto out;
+ }
+
+ tmp_buf = kvmalloc(fs_info->nodesize, GFP_KERNEL);
+ if (!tmp_buf) {
+ ret = -ENOMEM;
+ goto out;
+ }
+
+ left_path->search_commit_root = 1;
+ left_path->skip_locking = 1;
+ right_path->search_commit_root = 1;
+ right_path->skip_locking = 1;
+
+ /*
+ * Strategy: Go to the first items of both trees. Then do
+ *
+ * If both trees are at level 0
+ * Compare keys of current items
+ * If left < right treat left item as new, advance left tree
+ * and repeat
+ * If left > right treat right item as deleted, advance right tree
+ * and repeat
+ * If left == right do deep compare of items, treat as changed if
+ * needed, advance both trees and repeat
+ * If both trees are at the same level but not at level 0
+ * Compare keys of current nodes/leafs
+ * If left < right advance left tree and repeat
+ * If left > right advance right tree and repeat
+ * If left == right compare blockptrs of the next nodes/leafs
+ * If they match advance both trees but stay at the same level
+ * and repeat
+ * If they don't match advance both trees while allowing to go
+ * deeper and repeat
+ * If tree levels are different
+ * Advance the tree that needs it and repeat
+ *
+ * Advancing a tree means:
+ * If we are at level 0, try to go to the next slot. If that's not
+ * possible, go one level up and repeat. Stop when we found a level
+ * where we could go to the next slot. We may at this point be on a
+ * node or a leaf.
+ *
+ * If we are not at level 0 and not on shared tree blocks, go one
+ * level deeper.
+ *
+ * If we are not at level 0 and on shared tree blocks, go one slot to
+ * the right if possible or go up and right.
+ */
+
+ down_read(&fs_info->commit_root_sem);
+ left_level = btrfs_header_level(left_root->commit_root);
+ left_root_level = left_level;
+ left_path->nodes[left_level] =
+ btrfs_clone_extent_buffer(left_root->commit_root);
+ if (!left_path->nodes[left_level]) {
+ up_read(&fs_info->commit_root_sem);
+ ret = -ENOMEM;
+ goto out;
+ }
+
+ right_level = btrfs_header_level(right_root->commit_root);
+ right_root_level = right_level;
+ right_path->nodes[right_level] =
+ btrfs_clone_extent_buffer(right_root->commit_root);
+ if (!right_path->nodes[right_level]) {
+ up_read(&fs_info->commit_root_sem);
+ ret = -ENOMEM;
+ goto out;
+ }
+ up_read(&fs_info->commit_root_sem);
+
+ if (left_level == 0)
+ btrfs_item_key_to_cpu(left_path->nodes[left_level],
+ &left_key, left_path->slots[left_level]);
+ else
+ btrfs_node_key_to_cpu(left_path->nodes[left_level],
+ &left_key, left_path->slots[left_level]);
+ if (right_level == 0)
+ btrfs_item_key_to_cpu(right_path->nodes[right_level],
+ &right_key, right_path->slots[right_level]);
+ else
+ btrfs_node_key_to_cpu(right_path->nodes[right_level],
+ &right_key, right_path->slots[right_level]);
+
+ left_end_reached = right_end_reached = 0;
+ advance_left = advance_right = 0;
+
+ while (1) {
+ cond_resched();
+ if (advance_left && !left_end_reached) {
+ ret = tree_advance(left_path, &left_level,
+ left_root_level,
+ advance_left != ADVANCE_ONLY_NEXT,
+ &left_key);
+ if (ret == -1)
+ left_end_reached = ADVANCE;
+ else if (ret < 0)
+ goto out;
+ advance_left = 0;
+ }
+ if (advance_right && !right_end_reached) {
+ ret = tree_advance(right_path, &right_level,
+ right_root_level,
+ advance_right != ADVANCE_ONLY_NEXT,
+ &right_key);
+ if (ret == -1)
+ right_end_reached = ADVANCE;
+ else if (ret < 0)
+ goto out;
+ advance_right = 0;
+ }
+
+ if (left_end_reached && right_end_reached) {
+ ret = 0;
+ goto out;
+ } else if (left_end_reached) {
+ if (right_level == 0) {
+ ret = changed_cb(left_path, right_path,
+ &right_key,
+ BTRFS_COMPARE_TREE_DELETED,
+ ctx);
+ if (ret < 0)
+ goto out;
+ }
+ advance_right = ADVANCE;
+ continue;
+ } else if (right_end_reached) {
+ if (left_level == 0) {
+ ret = changed_cb(left_path, right_path,
+ &left_key,
+ BTRFS_COMPARE_TREE_NEW,
+ ctx);
+ if (ret < 0)
+ goto out;
+ }
+ advance_left = ADVANCE;
+ continue;
+ }
+
+ if (left_level == 0 && right_level == 0) {
+ cmp = btrfs_comp_cpu_keys(&left_key, &right_key);
+ if (cmp < 0) {
+ ret = changed_cb(left_path, right_path,
+ &left_key,
+ BTRFS_COMPARE_TREE_NEW,
+ ctx);
+ if (ret < 0)
+ goto out;
+ advance_left = ADVANCE;
+ } else if (cmp > 0) {
+ ret = changed_cb(left_path, right_path,
+ &right_key,
+ BTRFS_COMPARE_TREE_DELETED,
+ ctx);
+ if (ret < 0)
+ goto out;
+ advance_right = ADVANCE;
+ } else {
+ enum btrfs_compare_tree_result result;
+
+ WARN_ON(!extent_buffer_uptodate(left_path->nodes[0]));
+ ret = tree_compare_item(left_path, right_path,
+ tmp_buf);
+ if (ret)
+ result = BTRFS_COMPARE_TREE_CHANGED;
+ else
+ result = BTRFS_COMPARE_TREE_SAME;
+ ret = changed_cb(left_path, right_path,
+ &left_key, result, ctx);
+ if (ret < 0)
+ goto out;
+ advance_left = ADVANCE;
+ advance_right = ADVANCE;
+ }
+ } else if (left_level == right_level) {
+ cmp = btrfs_comp_cpu_keys(&left_key, &right_key);
+ if (cmp < 0) {
+ advance_left = ADVANCE;
+ } else if (cmp > 0) {
+ advance_right = ADVANCE;
+ } else {
+ left_blockptr = btrfs_node_blockptr(
+ left_path->nodes[left_level],
+ left_path->slots[left_level]);
+ right_blockptr = btrfs_node_blockptr(
+ right_path->nodes[right_level],
+ right_path->slots[right_level]);
+ left_gen = btrfs_node_ptr_generation(
+ left_path->nodes[left_level],
+ left_path->slots[left_level]);
+ right_gen = btrfs_node_ptr_generation(
+ right_path->nodes[right_level],
+ right_path->slots[right_level]);
+ if (left_blockptr == right_blockptr &&
+ left_gen == right_gen) {
+ /*
+ * As we're on a shared block, don't
+ * allow to go deeper.
+ */
+ advance_left = ADVANCE_ONLY_NEXT;
+ advance_right = ADVANCE_ONLY_NEXT;
+ } else {
+ advance_left = ADVANCE;
+ advance_right = ADVANCE;
+ }
+ }
+ } else if (left_level < right_level) {
+ advance_right = ADVANCE;
+ } else {
+ advance_left = ADVANCE;
+ }
+ }
+
+out:
+ btrfs_free_path(left_path);
+ btrfs_free_path(right_path);
+ kvfree(tmp_buf);
+ return ret;
+}
+
static int send_subvol(struct send_ctx *sctx)
{
int ret;
@@ -6583,6 +6967,38 @@
return btrfs_commit_transaction(trans);
}
+/*
+ * Make sure any existing dellaloc is flushed for any root used by a send
+ * operation so that we do not miss any data and we do not race with writeback
+ * finishing and changing a tree while send is using the tree. This could
+ * happen if a subvolume is in RW mode, has delalloc, is turned to RO mode and
+ * a send operation then uses the subvolume.
+ * After flushing delalloc ensure_commit_roots_uptodate() must be called.
+ */
+static int flush_delalloc_roots(struct send_ctx *sctx)
+{
+ struct btrfs_root *root = sctx->parent_root;
+ int ret;
+ int i;
+
+ if (root) {
+ ret = btrfs_start_delalloc_snapshot(root);
+ if (ret)
+ return ret;
+ btrfs_wait_ordered_extents(root, U64_MAX, 0, U64_MAX);
+ }
+
+ for (i = 0; i < sctx->clone_roots_cnt; i++) {
+ root = sctx->clone_roots[i].root;
+ ret = btrfs_start_delalloc_snapshot(root);
+ if (ret)
+ return ret;
+ btrfs_wait_ordered_extents(root, U64_MAX, 0, U64_MAX);
+ }
+
+ return 0;
+}
+
static void btrfs_root_dec_send_in_progress(struct btrfs_root* root)
{
spin_lock(&root->root_item_lock);
@@ -6598,6 +7014,13 @@
spin_unlock(&root->root_item_lock);
}
+static void dedupe_in_progress_warn(const struct btrfs_root *root)
+{
+ btrfs_warn_rl(root->fs_info,
+"cannot use root %llu for send while deduplications on it are in progress (%d in progress)",
+ root->root_key.objectid, root->dedupe_in_progress);
+}
+
long btrfs_ioctl_send(struct file *mnt_file, struct btrfs_ioctl_send_args *arg)
{
int ret = 0;
@@ -6621,6 +7044,11 @@
* making it RW. This also protects against deletion.
*/
spin_lock(&send_root->root_item_lock);
+ if (btrfs_root_readonly(send_root) && send_root->dedupe_in_progress) {
+ dedupe_in_progress_warn(send_root);
+ spin_unlock(&send_root->root_item_lock);
+ return -EAGAIN;
+ }
send_root->send_in_progress++;
spin_unlock(&send_root->root_item_lock);
@@ -6650,7 +7078,7 @@
goto out;
}
- if (!access_ok(VERIFY_READ, arg->clone_sources,
+ if (!access_ok(arg->clone_sources,
sizeof(*arg->clone_sources) *
arg->clone_sources_count)) {
ret = -EFAULT;
@@ -6755,6 +7183,13 @@
ret = -EPERM;
goto out;
}
+ if (clone_root->dedupe_in_progress) {
+ dedupe_in_progress_warn(clone_root);
+ spin_unlock(&clone_root->root_item_lock);
+ srcu_read_unlock(&fs_info->subvol_srcu, index);
+ ret = -EAGAIN;
+ goto out;
+ }
clone_root->send_in_progress++;
spin_unlock(&clone_root->root_item_lock);
srcu_read_unlock(&fs_info->subvol_srcu, index);
@@ -6789,6 +7224,13 @@
ret = -EPERM;
goto out;
}
+ if (sctx->parent_root->dedupe_in_progress) {
+ dedupe_in_progress_warn(sctx->parent_root);
+ spin_unlock(&sctx->parent_root->root_item_lock);
+ srcu_read_unlock(&fs_info->subvol_srcu, index);
+ ret = -EAGAIN;
+ goto out;
+ }
spin_unlock(&sctx->parent_root->root_item_lock);
srcu_read_unlock(&fs_info->subvol_srcu, index);
@@ -6807,13 +7249,31 @@
NULL);
sort_clone_roots = 1;
+ ret = flush_delalloc_roots(sctx);
+ if (ret)
+ goto out;
+
ret = ensure_commit_roots_uptodate(sctx);
if (ret)
goto out;
+ mutex_lock(&fs_info->balance_mutex);
+ if (test_bit(BTRFS_FS_BALANCE_RUNNING, &fs_info->flags)) {
+ mutex_unlock(&fs_info->balance_mutex);
+ btrfs_warn_rl(fs_info,
+ "cannot run send because a balance operation is in progress");
+ ret = -EAGAIN;
+ goto out;
+ }
+ fs_info->send_in_progress++;
+ mutex_unlock(&fs_info->balance_mutex);
+
current->journal_info = BTRFS_SEND_TRANS_STUB;
ret = send_subvol(sctx);
current->journal_info = NULL;
+ mutex_lock(&fs_info->balance_mutex);
+ fs_info->send_in_progress--;
+ mutex_unlock(&fs_info->balance_mutex);
if (ret < 0)
goto out;