From: Chen Yang <[email protected]> Date: Fri, 18 Jan 2013 14:54:31 +0800 Subject: [PATCH] Btrfs-progs/receive: sparse and pre-allocated file support for btrfs-send mechanism
When sending a file with sparse or pre-allocated part, these parts will be sent as ZERO streams, and it's unnecessary. To improve this, we add a punch command on the sending side, so the receiving side changed with it. The main change is adding the punch processing to receive command. Signed-off-by: Cheng Yang <[email protected]> --- cmds-receive.c | 27 +++++++++++++++++++++++++++ send-stream.c | 6 ++++++ send-stream.h | 1 + send.h | 3 ++- 4 files changed, 36 insertions(+), 1 deletions(-) diff --git a/cmds-receive.c b/cmds-receive.c index a8be6fa..74cbfc4 100644 --- a/cmds-receive.c +++ b/cmds-receive.c @@ -37,6 +37,7 @@ #include <sys/types.h> #include <sys/xattr.h> #include <uuid/uuid.h> +#include <linux/falloc.h> #include "ctree.h" #include "ioctl.h" @@ -508,6 +509,31 @@ out: return ret; } +static int process_punch(const char *path, u64 offset, u64 len, void *user) +{ + int ret = 0; + struct btrfs_receive *r = user; + char *full_path = path_cat(r->full_subvol_path, path); + + ret = open_inode_for_write(r, full_path); + if (ret < 0) + goto out; + + ret = fallocate(r->write_fd, + FALLOC_FL_PUNCH_HOLE | FALLOC_FL_KEEP_SIZE, + offset, len); + if (ret < 0) { + ret = -errno; + fprintf(stderr, "ERROR: punch %s failed. %s\n", + path, strerror(-ret)); + goto out; + } + +out: + free(full_path); + return ret; +} + static int process_write(const char *path, const void *data, u64 offset, u64 len, void *user) { @@ -777,6 +803,7 @@ struct btrfs_send_ops send_ops = { .link = process_link, .unlink = process_unlink, .rmdir = process_rmdir, + .punch = process_punch, .write = process_write, .clone = process_clone, .set_xattr = process_set_xattr, diff --git a/send-stream.c b/send-stream.c index 55fa728..9f3ede7 100644 --- a/send-stream.c +++ b/send-stream.c @@ -362,6 +362,12 @@ static int read_and_process_cmd(struct btrfs_send_stream *s) TLV_GET_STRING(s, BTRFS_SEND_A_PATH, &path); ret = s->ops->rmdir(path, s->user); break; + case BTRFS_SEND_C_PUNCH: + TLV_GET_STRING(s, BTRFS_SEND_A_PATH, &path); + TLV_GET_U64(s, BTRFS_SEND_A_FILE_OFFSET, &offset); + TLV_GET_U64(s, BTRFS_SEND_A_SIZE, &len); + ret = s->ops->punch(path, offset, len, s->user); + break; case BTRFS_SEND_C_WRITE: TLV_GET_STRING(s, BTRFS_SEND_A_PATH, &path); TLV_GET_U64(s, BTRFS_SEND_A_FILE_OFFSET, &offset); diff --git a/send-stream.h b/send-stream.h index b69b7f1..f83f2ac 100644 --- a/send-stream.h +++ b/send-stream.h @@ -34,6 +34,7 @@ struct btrfs_send_ops { int (*link)(const char *path, const char *lnk, void *user); int (*unlink)(const char *path, void *user); int (*rmdir)(const char *path, void *user); + int (*punch)(const char *path, u64 offset, u64 len, void *user); int (*write)(const char *path, const void *data, u64 offset, u64 len, void *user); int (*clone)(const char *path, u64 offset, u64 len, diff --git a/send.h b/send.h index 9934e94..10a88d2 100644 --- a/send.h +++ b/send.h @@ -20,7 +20,7 @@ #include "ctree.h" #define BTRFS_SEND_STREAM_MAGIC "btrfs-stream" -#define BTRFS_SEND_STREAM_VERSION 1 +#define BTRFS_SEND_STREAM_VERSION 2 #define BTRFS_SEND_BUF_SIZE (1024 * 64) #define BTRFS_SEND_READ_SIZE (1024 * 48) @@ -80,6 +80,7 @@ enum btrfs_send_cmd { BTRFS_SEND_C_WRITE, BTRFS_SEND_C_CLONE, + BTRFS_SEND_C_PUNCH, BTRFS_SEND_C_TRUNCATE, BTRFS_SEND_C_CHMOD, BTRFS_SEND_C_CHOWN, -- 1.7.7.6 -- To unsubscribe from this list: send the line "unsubscribe linux-btrfs" in the body of a message to [email protected] More majordomo info at http://vger.kernel.org/majordomo-info.html
