1 files changed, 207 insertions, 158 deletions

diff --git a/fs/btrfs/send.c b/fs/btrfs/send.c
index b1015f383f75..41b7cbd07025 100644
--- a/fs/btrfs/send.c
+++ b/fs/btrfs/send.c
@@ -4,6 +4,7 @@
  */
 
 #include <linux/bsearch.h>
+#include <linux/falloc.h>
 #include <linux/fs.h>
 #include <linux/file.h>
 #include <linux/sort.h>
@@ -178,6 +179,7 @@ struct send_ctx {
 	u64 cur_inode_rdev;
 	u64 cur_inode_last_extent;
 	u64 cur_inode_next_write_offset;
+	struct fs_path cur_inode_path;
 	bool cur_inode_new;
 	bool cur_inode_new_gen;
 	bool cur_inode_deleted;
@@ -436,6 +438,14 @@ static void fs_path_reset(struct fs_path *p)
 	}
 }
 
+static void init_path(struct fs_path *p)
+{
+	p->reversed = 0;
+	p->buf = p->inline_buf;
+	p->buf_len = FS_PATH_INLINE_SIZE;
+	fs_path_reset(p);
+}
+
 static struct fs_path *fs_path_alloc(void)
 {
 	struct fs_path *p;
@@ -443,10 +453,7 @@ static struct fs_path *fs_path_alloc(void)
 	p = kmalloc(sizeof(*p), GFP_KERNEL);
 	if (!p)
 		return NULL;
-	p->reversed = 0;
-	p->buf = p->inline_buf;
-	p->buf_len = FS_PATH_INLINE_SIZE;
-	fs_path_reset(p);
+	init_path(p);
 	return p;
 }
 
@@ -471,7 +478,7 @@ static void fs_path_free(struct fs_path *p)
 	kfree(p);
 }
 
-static int fs_path_len(struct fs_path *p)
+static inline int fs_path_len(const struct fs_path *p)
 {
 	return p->end - p->start;
 }
@@ -487,10 +494,8 @@ static int fs_path_ensure_buf(struct fs_path *p, int len)
 	if (p->buf_len >= len)
 		return 0;
 
-	if (len > PATH_MAX) {
-		WARN_ON(1);
-		return -ENOMEM;
-	}
+	if (WARN_ON(len > PATH_MAX))
+		return -ENAMETOOLONG;
 
 	path_len = p->end - p->start;
 	old_buf_len = p->buf_len;
@@ -626,6 +631,14 @@ static void fs_path_unreverse(struct fs_path *p)
 	p->reversed = 0;
 }
 
+static inline bool is_current_inode_path(const struct send_ctx *sctx,
+					 const struct fs_path *path)
+{
+	const struct fs_path *cur = &sctx->cur_inode_path;
+
+	return (strncmp(path->start, cur->start, fs_path_len(cur)) == 0);
+}
+
 static struct btrfs_path *alloc_path_for_send(void)
 {
 	struct btrfs_path *path;
@@ -2452,6 +2465,14 @@ static int get_cur_path(struct send_ctx *sctx, u64 ino, u64 gen,
 	u64 parent_inode = 0;
 	u64 parent_gen = 0;
 	int stop = 0;
+	const bool is_cur_inode = (ino == sctx->cur_ino && gen == sctx->cur_inode_gen);
+
+	if (is_cur_inode && fs_path_len(&sctx->cur_inode_path) > 0) {
+		if (dest != &sctx->cur_inode_path)
+			return fs_path_copy(dest, &sctx->cur_inode_path);
+
+		return 0;
+	}
 
 	name = fs_path_alloc();
 	if (!name) {
@@ -2503,8 +2524,12 @@ static int get_cur_path(struct send_ctx *sctx, u64 ino, u64 gen,
 
 out:
 	fs_path_free(name);
-	if (!ret)
+	if (!ret) {
 		fs_path_unreverse(dest);
+		if (is_cur_inode && dest != &sctx->cur_inode_path)
+			ret = fs_path_copy(&sctx->cur_inode_path, dest);
+	}
+
 	return ret;
 }
 
@@ -2599,6 +2624,47 @@ out:
 	return ret;
 }
 
+static struct fs_path *get_cur_inode_path(struct send_ctx *sctx)
+{
+	if (fs_path_len(&sctx->cur_inode_path) == 0) {
+		int ret;
+
+		ret = get_cur_path(sctx, sctx->cur_ino, sctx->cur_inode_gen,
+				   &sctx->cur_inode_path);
+		if (ret < 0)
+			return ERR_PTR(ret);
+	}
+
+	return &sctx->cur_inode_path;
+}
+
+static struct fs_path *get_path_for_command(struct send_ctx *sctx, u64 ino, u64 gen)
+{
+	struct fs_path *path;
+	int ret;
+
+	if (ino == sctx->cur_ino && gen == sctx->cur_inode_gen)
+		return get_cur_inode_path(sctx);
+
+	path = fs_path_alloc();
+	if (!path)
+		return ERR_PTR(-ENOMEM);
+
+	ret = get_cur_path(sctx, ino, gen, path);
+	if (ret < 0) {
+		fs_path_free(path);
+		return ERR_PTR(ret);
+	}
+
+	return path;
+}
+
+static void free_path_for_command(const struct send_ctx *sctx, struct fs_path *path)
+{
+	if (path != &sctx->cur_inode_path)
+		fs_path_free(path);
+}
+
 static int send_truncate(struct send_ctx *sctx, u64 ino, u64 gen, u64 size)
 {
 	struct btrfs_fs_info *fs_info = sctx->send_root->fs_info;
@@ -2607,17 +2673,14 @@ static int send_truncate(struct send_ctx *sctx, u64 ino, u64 gen, u64 size)
 
 	btrfs_debug(fs_info, "send_truncate %llu size=%llu", ino, size);
 
-	p = fs_path_alloc();
-	if (!p)
-		return -ENOMEM;
+	p = get_path_for_command(sctx, ino, gen);
+	if (IS_ERR(p))
+		return PTR_ERR(p);
 
 	ret = begin_cmd(sctx, BTRFS_SEND_C_TRUNCATE);
 	if (ret < 0)
 		goto out;
 
-	ret = get_cur_path(sctx, ino, gen, p);
-	if (ret < 0)
-		goto out;
 	TLV_PUT_PATH(sctx, BTRFS_SEND_A_PATH, p);
 	TLV_PUT_U64(sctx, BTRFS_SEND_A_SIZE, size);
 
@@ -2625,7 +2688,7 @@ static int send_truncate(struct send_ctx *sctx, u64 ino, u64 gen, u64 size)
 
 tlv_put_failure:
 out:
-	fs_path_free(p);
+	free_path_for_command(sctx, p);
 	return ret;
 }
 
@@ -2637,17 +2700,14 @@ static int send_chmod(struct send_ctx *sctx, u64 ino, u64 gen, u64 mode)
 
 	btrfs_debug(fs_info, "send_chmod %llu mode=%llu", ino, mode);
 
-	p = fs_path_alloc();
-	if (!p)
-		return -ENOMEM;
+	p = get_path_for_command(sctx, ino, gen);
+	if (IS_ERR(p))
+		return PTR_ERR(p);
 
 	ret = begin_cmd(sctx, BTRFS_SEND_C_CHMOD);
 	if (ret < 0)
 		goto out;
 
-	ret = get_cur_path(sctx, ino, gen, p);
-	if (ret < 0)
-		goto out;
 	TLV_PUT_PATH(sctx, BTRFS_SEND_A_PATH, p);
 	TLV_PUT_U64(sctx, BTRFS_SEND_A_MODE, mode & 07777);
 
@@ -2655,7 +2715,7 @@ static int send_chmod(struct send_ctx *sctx, u64 ino, u64 gen, u64 mode)
 
 tlv_put_failure:
 out:
-	fs_path_free(p);
+	free_path_for_command(sctx, p);
 	return ret;
 }
 
@@ -2670,17 +2730,14 @@ static int send_fileattr(struct send_ctx *sctx, u64 ino, u64 gen, u64 fileattr)
 
 	btrfs_debug(fs_info, "send_fileattr %llu fileattr=%llu", ino, fileattr);
 
-	p = fs_path_alloc();
-	if (!p)
-		return -ENOMEM;
+	p = get_path_for_command(sctx, ino, gen);
+	if (IS_ERR(p))
+		return PTR_ERR(p);
 
 	ret = begin_cmd(sctx, BTRFS_SEND_C_FILEATTR);
 	if (ret < 0)
 		goto out;
 
-	ret = get_cur_path(sctx, ino, gen, p);
-	if (ret < 0)
-		goto out;
 	TLV_PUT_PATH(sctx, BTRFS_SEND_A_PATH, p);
 	TLV_PUT_U64(sctx, BTRFS_SEND_A_FILEATTR, fileattr);
 
@@ -2688,7 +2745,7 @@ static int send_fileattr(struct send_ctx *sctx, u64 ino, u64 gen, u64 fileattr)
 
 tlv_put_failure:
 out:
-	fs_path_free(p);
+	free_path_for_command(sctx, p);
 	return ret;
 }
 
@@ -2701,17 +2758,14 @@ static int send_chown(struct send_ctx *sctx, u64 ino, u64 gen, u64 uid, u64 gid)
 	btrfs_debug(fs_info, "send_chown %llu uid=%llu, gid=%llu",
 		    ino, uid, gid);
 
-	p = fs_path_alloc();
-	if (!p)
-		return -ENOMEM;
+	p = get_path_for_command(sctx, ino, gen);
+	if (IS_ERR(p))
+		return PTR_ERR(p);
 
 	ret = begin_cmd(sctx, BTRFS_SEND_C_CHOWN);
 	if (ret < 0)
 		goto out;
 
-	ret = get_cur_path(sctx, ino, gen, p);
-	if (ret < 0)
-		goto out;
 	TLV_PUT_PATH(sctx, BTRFS_SEND_A_PATH, p);
 	TLV_PUT_U64(sctx, BTRFS_SEND_A_UID, uid);
 	TLV_PUT_U64(sctx, BTRFS_SEND_A_GID, gid);
@@ -2720,7 +2774,7 @@ static int send_chown(struct send_ctx *sctx, u64 ino, u64 gen, u64 uid, u64 gid)
 
 tlv_put_failure:
 out:
-	fs_path_free(p);
+	free_path_for_command(sctx, p);
 	return ret;
 }
 
@@ -2737,9 +2791,9 @@ static int send_utimes(struct send_ctx *sctx, u64 ino, u64 gen)
 
 	btrfs_debug(fs_info, "send_utimes %llu", ino);
 
-	p = fs_path_alloc();
-	if (!p)
-		return -ENOMEM;
+	p = get_path_for_command(sctx, ino, gen);
+	if (IS_ERR(p))
+		return PTR_ERR(p);
 
 	path = alloc_path_for_send();
 	if (!path) {
@@ -2764,9 +2818,6 @@ static int send_utimes(struct send_ctx *sctx, u64 ino, u64 gen)
 	if (ret < 0)
 		goto out;
 
-	ret = get_cur_path(sctx, ino, gen, p);
-	if (ret < 0)
-		goto out;
 	TLV_PUT_PATH(sctx, BTRFS_SEND_A_PATH, p);
 	TLV_PUT_BTRFS_TIMESPEC(sctx, BTRFS_SEND_A_ATIME, eb, &ii->atime);
 	TLV_PUT_BTRFS_TIMESPEC(sctx, BTRFS_SEND_A_MTIME, eb, &ii->mtime);
@@ -2778,7 +2829,7 @@ static int send_utimes(struct send_ctx *sctx, u64 ino, u64 gen)
 
 tlv_put_failure:
 out:
-	fs_path_free(p);
+	free_path_for_command(sctx, p);
 	btrfs_free_path(path);
 	return ret;
 }
@@ -3114,6 +3165,11 @@ static int orphanize_inode(struct send_ctx *sctx, u64 ino, u64 gen,
 		goto out;
 
 	ret = send_rename(sctx, path, orphan);
+	if (ret < 0)
+		goto out;
+
+	if (ino == sctx->cur_ino && gen == sctx->cur_inode_gen)
+		ret = fs_path_copy(&sctx->cur_inode_path, orphan);
 
 out:
 	fs_path_free(orphan);
@@ -4167,6 +4223,23 @@ out:
 	return ret;
 }
 
+static int rename_current_inode(struct send_ctx *sctx,
+				struct fs_path *current_path,
+				struct fs_path *new_path)
+{
+	int ret;
+
+	ret = send_rename(sctx, current_path, new_path);
+	if (ret < 0)
+		return ret;
+
+	ret = fs_path_copy(&sctx->cur_inode_path, new_path);
+	if (ret < 0)
+		return ret;
+
+	return fs_path_copy(current_path, new_path);
+}
+
 /*
  * This does all the move/link/unlink/rmdir magic.
  */
@@ -4181,9 +4254,9 @@ static int process_recorded_refs(struct send_ctx *sctx, int *pending_move)
 	u64 ow_inode = 0;
 	u64 ow_gen;
 	u64 ow_mode;
-	int did_overwrite = 0;
-	int is_orphan = 0;
 	u64 last_dir_ino_rm = 0;
+	bool did_overwrite = false;
+	bool is_orphan = false;
 	bool can_rename = true;
 	bool orphanized_dir = false;
 	bool orphanized_ancestor = false;
@@ -4225,14 +4298,14 @@ static int process_recorded_refs(struct send_ctx *sctx, int *pending_move)
 		if (ret < 0)
 			goto out;
 		if (ret)
-			did_overwrite = 1;
+			did_overwrite = true;
 	}
 	if (sctx->cur_inode_new || did_overwrite) {
 		ret = gen_unique_name(sctx, sctx->cur_ino,
 				sctx->cur_inode_gen, valid_path);
 		if (ret < 0)
 			goto out;
-		is_orphan = 1;
+		is_orphan = true;
 	} else {
 		ret = get_cur_path(sctx, sctx->cur_ino, sctx->cur_inode_gen,
 				valid_path);
@@ -4357,6 +4430,7 @@ static int process_recorded_refs(struct send_ctx *sctx, int *pending_move)
 				if (ret > 0) {
 					orphanized_ancestor = true;
 					fs_path_reset(valid_path);
+					fs_path_reset(&sctx->cur_inode_path);
 					ret = get_cur_path(sctx, sctx->cur_ino,
 							   sctx->cur_inode_gen,
 							   valid_path);
@@ -4452,13 +4526,10 @@ static int process_recorded_refs(struct send_ctx *sctx, int *pending_move)
 		 * it depending on the inode mode.
 		 */
 		if (is_orphan && can_rename) {
-			ret = send_rename(sctx, valid_path, cur->full_path);
-			if (ret < 0)
-				goto out;
-			is_orphan = 0;
-			ret = fs_path_copy(valid_path, cur->full_path);
+			ret = rename_current_inode(sctx, valid_path, cur->full_path);
 			if (ret < 0)
 				goto out;
+			is_orphan = false;
 		} else if (can_rename) {
 			if (S_ISDIR(sctx->cur_inode_mode)) {
 				/*
@@ -4466,10 +4537,7 @@ static int process_recorded_refs(struct send_ctx *sctx, int *pending_move)
 				 * dirs, we always have one new and one deleted
 				 * ref. The deleted ref is ignored later.
 				 */
-				ret = send_rename(sctx, valid_path,
-						  cur->full_path);
-				if (!ret)
-					ret = fs_path_copy(valid_path,
+				ret = rename_current_inode(sctx, valid_path,
 							   cur->full_path);
 				if (ret < 0)
 					goto out;
@@ -4516,7 +4584,7 @@ static int process_recorded_refs(struct send_ctx *sctx, int *pending_move)
 					sctx->cur_inode_gen, valid_path);
 			if (ret < 0)
 				goto out;
-			is_orphan = 1;
+			is_orphan = true;
 		}
 
 		list_for_each_entry(cur, &sctx->deleted_refs, list) {
@@ -4562,6 +4630,8 @@ static int process_recorded_refs(struct send_ctx *sctx, int *pending_move)
 				ret = send_unlink(sctx, cur->full_path);
 				if (ret < 0)
 					goto out;
+				if (is_current_inode_path(sctx, cur->full_path))
+					fs_path_reset(&sctx->cur_inode_path);
 			}
 			ret = dup_ref(cur, &check_dirs);
 			if (ret < 0)
@@ -4880,11 +4950,15 @@ out:
 }
 
 static int send_set_xattr(struct send_ctx *sctx,
-			  struct fs_path *path,
 			  const char *name, int name_len,
 			  const char *data, int data_len)
 {
-	int ret = 0;
+	struct fs_path *path;
+	int ret;
+
+	path = get_cur_inode_path(sctx);
+	if (IS_ERR(path))
+		return PTR_ERR(path);
 
 	ret = begin_cmd(sctx, BTRFS_SEND_C_SET_XATTR);
 	if (ret < 0)
@@ -4925,19 +4999,13 @@ static int __process_new_xattr(int num, struct btrfs_key *di_key,
 			       const char *name, int name_len, const char *data,
 			       int data_len, void *ctx)
 {
-	int ret;
 	struct send_ctx *sctx = ctx;
-	struct fs_path *p;
 	struct posix_acl_xattr_header dummy_acl;
 
 	/* Capabilities are emitted by finish_inode_if_needed */
 	if (!strncmp(name, XATTR_NAME_CAPS, name_len))
 		return 0;
 
-	p = fs_path_alloc();
-	if (!p)
-		return -ENOMEM;
-
 	/*
 	 * This hack is needed because empty acls are stored as zero byte
 	 * data in xattrs. Problem with that is, that receiving these zero byte
@@ -4954,38 +5022,21 @@ static int __process_new_xattr(int num, struct btrfs_key *di_key,
 		}
 	}
 
-	ret = get_cur_path(sctx, sctx->cur_ino, sctx->cur_inode_gen, p);
-	if (ret < 0)
-		goto out;
-
-	ret = send_set_xattr(sctx, p, name, name_len, data, data_len);
-
-out:
-	fs_path_free(p);
-	return ret;
+	return send_set_xattr(sctx, name, name_len, data, data_len);
 }
 
 static int __process_deleted_xattr(int num, struct btrfs_key *di_key,
 				   const char *name, int name_len,
 				   const char *data, int data_len, void *ctx)
 {
-	int ret;
 	struct send_ctx *sctx = ctx;
 	struct fs_path *p;
 
-	p = fs_path_alloc();
-	if (!p)
-		return -ENOMEM;
-
-	ret = get_cur_path(sctx, sctx->cur_ino, sctx->cur_inode_gen, p);
-	if (ret < 0)
-		goto out;
-
-	ret = send_remove_xattr(sctx, p, name, name_len);
+	p = get_cur_inode_path(sctx);
+	if (IS_ERR(p))
+		return PTR_ERR(p);
 
-out:
-	fs_path_free(p);
-	return ret;
+	return send_remove_xattr(sctx, p, name, name_len);
 }
 
 static int process_new_xattr(struct send_ctx *sctx)
@@ -5218,21 +5269,13 @@ static int process_verity(struct send_ctx *sctx)
 	if (ret < 0)
 		goto iput;
 
-	p = fs_path_alloc();
-	if (!p) {
-		ret = -ENOMEM;
+	p = get_cur_inode_path(sctx);
+	if (IS_ERR(p)) {
+		ret = PTR_ERR(p);
 		goto iput;
 	}
-	ret = get_cur_path(sctx, sctx->cur_ino, sctx->cur_inode_gen, p);
-	if (ret < 0)
-		goto free_path;
 
 	ret = send_verity(sctx, p, sctx->verity_descriptor);
-	if (ret < 0)
-		goto free_path;
-
-free_path:
-	fs_path_free(p);
 iput:
 	iput(inode);
 	return ret;
@@ -5354,31 +5397,25 @@ static int send_write(struct send_ctx *sctx, u64 offset, u32 len)
 	int ret = 0;
 	struct fs_path *p;
 
-	p = fs_path_alloc();
-	if (!p)
-		return -ENOMEM;
-
 	btrfs_debug(fs_info, "send_write offset=%llu, len=%d", offset, len);
 
-	ret = begin_cmd(sctx, BTRFS_SEND_C_WRITE);
-	if (ret < 0)
-		goto out;
+	p = get_cur_inode_path(sctx);
+	if (IS_ERR(p))
+		return PTR_ERR(p);
 
-	ret = get_cur_path(sctx, sctx->cur_ino, sctx->cur_inode_gen, p);
+	ret = begin_cmd(sctx, BTRFS_SEND_C_WRITE);
 	if (ret < 0)
-		goto out;
+		return ret;
 
 	TLV_PUT_PATH(sctx, BTRFS_SEND_A_PATH, p);
 	TLV_PUT_U64(sctx, BTRFS_SEND_A_FILE_OFFSET, offset);
 	ret = put_file_data(sctx, offset, len);
 	if (ret < 0)
-		goto out;
+		return ret;
 
 	ret = send_cmd(sctx);
 
 tlv_put_failure:
-out:
-	fs_path_free(p);
 	return ret;
 }
 
@@ -5391,6 +5428,7 @@ static int send_clone(struct send_ctx *sctx,
 {
 	int ret = 0;
 	struct fs_path *p;
+	struct fs_path *cur_inode_path;
 	u64 gen;
 
 	btrfs_debug(sctx->send_root->fs_info,
@@ -5398,6 +5436,10 @@ static int send_clone(struct send_ctx *sctx,
 		    offset, len, btrfs_root_id(clone_root->root),
 		    clone_root->ino, clone_root->offset);
 
+	cur_inode_path = get_cur_inode_path(sctx);
+	if (IS_ERR(cur_inode_path))
+		return PTR_ERR(cur_inode_path);
+
 	p = fs_path_alloc();
 	if (!p)
 		return -ENOMEM;
@@ -5406,13 +5448,9 @@ static int send_clone(struct send_ctx *sctx,
 	if (ret < 0)
 		goto out;
 
-	ret = get_cur_path(sctx, sctx->cur_ino, sctx->cur_inode_gen, p);
-	if (ret < 0)
-		goto out;
-
 	TLV_PUT_U64(sctx, BTRFS_SEND_A_FILE_OFFSET, offset);
 	TLV_PUT_U64(sctx, BTRFS_SEND_A_CLONE_LEN, len);
-	TLV_PUT_PATH(sctx, BTRFS_SEND_A_PATH, p);
+	TLV_PUT_PATH(sctx, BTRFS_SEND_A_PATH, cur_inode_path);
 
 	if (clone_root->root == sctx->send_root) {
 		ret = get_inode_gen(sctx->send_root, clone_root->ino, &gen);
@@ -5463,27 +5501,45 @@ static int send_update_extent(struct send_ctx *sctx,
 	int ret = 0;
 	struct fs_path *p;
 
-	p = fs_path_alloc();
-	if (!p)
-		return -ENOMEM;
+	p = get_cur_inode_path(sctx);
+	if (IS_ERR(p))
+		return PTR_ERR(p);
 
 	ret = begin_cmd(sctx, BTRFS_SEND_C_UPDATE_EXTENT);
 	if (ret < 0)
-		goto out;
+		return ret;
+
+	TLV_PUT_PATH(sctx, BTRFS_SEND_A_PATH, p);
+	TLV_PUT_U64(sctx, BTRFS_SEND_A_FILE_OFFSET, offset);
+	TLV_PUT_U64(sctx, BTRFS_SEND_A_SIZE, len);
+
+	ret = send_cmd(sctx);
 
-	ret = get_cur_path(sctx, sctx->cur_ino, sctx->cur_inode_gen, p);
+tlv_put_failure:
+	return ret;
+}
+
+static int send_fallocate(struct send_ctx *sctx, u32 mode, u64 offset, u64 len)
+{
+	struct fs_path *path;
+	int ret;
+
+	path = get_cur_inode_path(sctx);
+	if (IS_ERR(path))
+		return PTR_ERR(path);
+
+	ret = begin_cmd(sctx, BTRFS_SEND_C_FALLOCATE);
 	if (ret < 0)
-		goto out;
+		return ret;
 
-	TLV_PUT_PATH(sctx, BTRFS_SEND_A_PATH, p);
+	TLV_PUT_PATH(sctx, BTRFS_SEND_A_PATH, path);
+	TLV_PUT_U32(sctx, BTRFS_SEND_A_FALLOCATE_MODE, mode);
 	TLV_PUT_U64(sctx, BTRFS_SEND_A_FILE_OFFSET, offset);
 	TLV_PUT_U64(sctx, BTRFS_SEND_A_SIZE, len);
 
 	ret = send_cmd(sctx);
 
 tlv_put_failure:
-out:
-	fs_path_free(p);
 	return ret;
 }
 
@@ -5495,6 +5551,14 @@ static int send_hole(struct send_ctx *sctx, u64 end)
 	int ret = 0;
 
 	/*
+	 * Starting with send stream v2 we have fallocate and can use it to
+	 * punch holes instead of sending writes full of zeroes.
+	 */
+	if (proto_cmd_ok(sctx, BTRFS_SEND_C_FALLOCATE))
+		return send_fallocate(sctx, FALLOC_FL_PUNCH_HOLE | FALLOC_FL_KEEP_SIZE,
+				      offset, end - offset);
+
+	/*
 	 * A hole that starts at EOF or beyond it. Since we do not yet support
 	 * fallocate (for extent preallocation and hole punching), sending a
 	 * write of zeroes starting at EOF or beyond would later require issuing
@@ -5512,12 +5576,10 @@ static int send_hole(struct send_ctx *sctx, u64 end)
 	if (sctx->flags & BTRFS_SEND_FLAG_NO_FILE_DATA)
 		return send_update_extent(sctx, offset, end - offset);
 
-	p = fs_path_alloc();
-	if (!p)
-		return -ENOMEM;
-	ret = get_cur_path(sctx, sctx->cur_ino, sctx->cur_inode_gen, p);
-	if (ret < 0)
-		goto tlv_put_failure;
+	p = get_cur_inode_path(sctx);
+	if (IS_ERR(p))
+		return PTR_ERR(p);
+
 	while (offset < end) {
 		u64 len = min(end - offset, read_size);
 
@@ -5538,7 +5600,6 @@ static int send_hole(struct send_ctx *sctx, u64 end)
 	}
 	sctx->cur_inode_next_write_offset = offset;
 tlv_put_failure:
-	fs_path_free(p);
 	return ret;
 }
 
@@ -5561,9 +5622,9 @@ static int send_encoded_inline_extent(struct send_ctx *sctx,
 	if (IS_ERR(inode))
 		return PTR_ERR(inode);
 
-	fspath = fs_path_alloc();
-	if (!fspath) {
-		ret = -ENOMEM;
+	fspath = get_cur_inode_path(sctx);
+	if (IS_ERR(fspath)) {
+		ret = PTR_ERR(fspath);
 		goto out;
 	}
 
@@ -5571,10 +5632,6 @@ static int send_encoded_inline_extent(struct send_ctx *sctx,
 	if (ret < 0)
 		goto out;
 
-	ret = get_cur_path(sctx, sctx->cur_ino, sctx->cur_inode_gen, fspath);
-	if (ret < 0)
-		goto out;
-
 	btrfs_item_key_to_cpu(leaf, &key, path->slots[0]);
 	ei = btrfs_item_ptr(leaf, path->slots[0], struct btrfs_file_extent_item);
 	ram_bytes = btrfs_file_extent_ram_bytes(leaf, ei);
@@ -5603,7 +5660,6 @@ static int send_encoded_inline_extent(struct send_ctx *sctx,
 
 tlv_put_failure:
 out:
-	fs_path_free(fspath);
 	iput(inode);
 	return ret;
 }
@@ -5628,9 +5684,9 @@ static int send_encoded_extent(struct send_ctx *sctx, struct btrfs_path *path,
 	if (IS_ERR(inode))
 		return PTR_ERR(inode);
 
-	fspath = fs_path_alloc();
-	if (!fspath) {
-		ret = -ENOMEM;
+	fspath = get_cur_inode_path(sctx);
+	if (IS_ERR(fspath)) {
+		ret = PTR_ERR(fspath);
 		goto out;
 	}
 
@@ -5638,10 +5694,6 @@ static int send_encoded_extent(struct send_ctx *sctx, struct btrfs_path *path,
 	if (ret < 0)
 		goto out;
 
-	ret = get_cur_path(sctx, sctx->cur_ino, sctx->cur_inode_gen, fspath);
-	if (ret < 0)
-		goto out;
-
 	btrfs_item_key_to_cpu(leaf, &key, path->slots[0]);
 	ei = btrfs_item_ptr(leaf, path->slots[0], struct btrfs_file_extent_item);
 	disk_bytenr = btrfs_file_extent_disk_bytenr(leaf, ei);
@@ -5708,7 +5760,6 @@ static int send_encoded_extent(struct send_ctx *sctx, struct btrfs_path *path,
 
 tlv_put_failure:
 out:
-	fs_path_free(fspath);
 	iput(inode);
 	return ret;
 }
@@ -5838,7 +5889,6 @@ static int send_extent_data(struct send_ctx *sctx, struct btrfs_path *path,
  */
 static int send_capabilities(struct send_ctx *sctx)
 {
-	struct fs_path *fspath = NULL;
 	struct btrfs_path *path;
 	struct btrfs_dir_item *di;
 	struct extent_buffer *leaf;
@@ -5864,25 +5914,19 @@ static int send_capabilities(struct send_ctx *sctx)
 	leaf = path->nodes[0];
 	buf_len = btrfs_dir_data_len(leaf, di);
 
-	fspath = fs_path_alloc();
 	buf = kmalloc(buf_len, GFP_KERNEL);
-	if (!fspath || !buf) {
+	if (!buf) {
 		ret = -ENOMEM;
 		goto out;
 	}
 
-	ret = get_cur_path(sctx, sctx->cur_ino, sctx->cur_inode_gen, fspath);
-	if (ret < 0)
-		goto out;
-
 	data_ptr = (unsigned long)(di + 1) + btrfs_dir_name_len(leaf, di);
 	read_extent_buffer(leaf, buf, data_ptr, buf_len);
 
-	ret = send_set_xattr(sctx, fspath, XATTR_NAME_CAPS,
+	ret = send_set_xattr(sctx, XATTR_NAME_CAPS,
 			strlen(XATTR_NAME_CAPS), buf, buf_len);
 out:
 	kfree(buf);
-	fs_path_free(fspath);
 	btrfs_free_path(path);
 	return ret;
 }
@@ -6908,6 +6952,7 @@ static int changed_inode(struct send_ctx *sctx,
 	sctx->cur_inode_last_extent = (u64)-1;
 	sctx->cur_inode_next_write_offset = 0;
 	sctx->ignore_cur_inode = false;
+	fs_path_reset(&sctx->cur_inode_path);
 
 	/*
 	 * Set send_progress to current inode. This will tell all get_cur_xxx
@@ -8180,6 +8225,7 @@ long btrfs_ioctl_send(struct btrfs_inode *inode, const struct btrfs_ioctl_send_a
 		goto out;
 	}
 
+	init_path(&sctx->cur_inode_path);
 	INIT_LIST_HEAD(&sctx->new_refs);
 	INIT_LIST_HEAD(&sctx->deleted_refs);
 
@@ -8465,6 +8511,9 @@ out:
 		btrfs_lru_cache_clear(&sctx->dir_created_cache);
 		btrfs_lru_cache_clear(&sctx->dir_utimes_cache);
 
+		if (sctx->cur_inode_path.buf != sctx->cur_inode_path.inline_buf)
+			kfree(sctx->cur_inode_path.buf);
+
 		kfree(sctx);
 	}