On Mon, Dec 19, 2011 at 09:47:06AM -0500, Chris Mason wrote:
> On Mon, Dec 19, 2011 at 03:25:39PM +0100, David Sterba wrote:
> > This is a standalone tool I've used to exercise the ioctl, simply pass
> Could you please add this to btrfs filesystem stat <filename>
Here it is, but I haven't really thought about the userspace interface and
calling it 'stat' just for reading compressed size does not seem right (and I
have renamed to 'csize' for now).
I will extend the ioctl to return the uncompressed size as well, it is provided
by the extent anyway. The original implementation returned just one u64 for the
whole file, I did the range-aware version because the lock_extent blocked for a
long time when the file was being modified and it could be avoided. However I
missed the options to utilize the information provided by the extents,
so this is not a final version.
From: David Sterba <dste...@suse.cz>
Signed-off-by: David Sterba <dste...@suse.cz>
---
btrfs.c | 9 ++++++++-
btrfs_cmds.c | 53 +++++++++++++++++++++++++++++++++++++++++++++++++++++
btrfs_cmds.h | 1 +
ioctl.h | 11 +++++++++++
4 files changed, 73 insertions(+), 1 deletions(-)
diff --git a/btrfs.c b/btrfs.c
index 1def354..5ce207a 100644
--- a/btrfs.c
+++ b/btrfs.c
@@ -128,7 +128,14 @@ static struct Command commands[] = {
"filesystem label", "<device> [<newlabel>]\n"
"With one argument, get the label of filesystem on <device>.\n"
"If <newlabel> is passed, set the filesystem label to <newlabel>.\n"
- "The filesystem must be unmounted.\n"
+ "The filesystem must be unmounted."
+ },
+ { do_compr_size, -1,
+ "filesystem csize", "[-s start] [-e end] file\n"
+ "Read compressed size of extents in the range [start,end)\n"
+ "-s start range start inclusive\n"
+ "-e end range end exclusive\n",
+ NULL
},
{ do_scrub_start, -1,
"scrub start", "[-Bdqr] <path>|<device>\n"
diff --git a/btrfs_cmds.c b/btrfs_cmds.c
index b59e9cb..4c8bf5c 100644
--- a/btrfs_cmds.c
+++ b/btrfs_cmds.c
@@ -1305,3 +1305,56 @@ out:
free(inodes);
return ret;
}
+
+int do_compr_size(int argc, char **argv)
+{
+ int ret;
+ int fd;
+ struct btrfs_ioctl_compr_size_args args;
+
+ args.start = 0;
+ args.end = (u64)-1;
+ optind = 1;
+ while (1) {
+ int c = getopt(argc, argv, "s:e:");
+ if (c < 0)
+ break;
+ switch (c) {
+ case 's':
+ args.start = parse_size(optarg);
+ break;
+ case 'e':
+ args.end = parse_size(optarg);
+ break;
+ default:
+ fprintf(stderr, "ERROR: Invalid arguments for csize\n");
+ return 1;
+ }
+ }
+
+ if (args.start > args.end) {
+ fprintf(stderr, "ERROR: Invalid range for csize\n");
+ return 1;
+ }
+
+ if (argc - optind == 0) {
+ fprintf(stderr, "ERROR: Invalid arguments for csize\n");
+ return 1;
+ }
+ argc -= optind;
+
+ fd = open_file_or_dir(argv[optind]);
+ if (fd < 0) {
+ fprintf(stderr, "ERROR: can't access '%s'\n", argv[optind]);
+ return 1;
+ }
+
+ ret = ioctl(fd, BTRFS_IOC_COMPR_SIZE, &args);
+ if (ret < 0) {
+ fprintf(stderr, "ERROR: ioctl returned %d, errno %d %s\n", ret,
errno, strerror(errno));
+ return errno;
+ }
+
+ printf("Compressed size: %llu\n", args.size << 9);
+ return 0;
+}
diff --git a/btrfs_cmds.h b/btrfs_cmds.h
index 81182b1..d171214 100644
--- a/btrfs_cmds.h
+++ b/btrfs_cmds.h
@@ -42,3 +42,4 @@ int open_file_or_dir(const char *fname);
int do_ino_to_path(int nargs, char **argv);
int do_logical_to_ino(int nargs, char **argv);
char *path_for_root(int fd, u64 root);
+int do_compr_size(int argc, char **argv);
diff --git a/ioctl.h b/ioctl.h
index 1ae7537..792ffc0 100644
--- a/ioctl.h
+++ b/ioctl.h
@@ -224,6 +224,15 @@ struct btrfs_ioctl_logical_ino_args {
__u64 inodes;
};
+struct btrfs_ioctl_compr_size_args {
+ /* Range start, inclusive */
+ __u64 start; /* in */
+ /* Range end, exclusive */
+ __u64 end; /* in */
+ __u64 size; /* out */
+ __u64 reserved[2];
+};
+
/* BTRFS_IOC_SNAP_CREATE is no longer used by the btrfs command */
#define BTRFS_IOC_SNAP_CREATE _IOW(BTRFS_IOCTL_MAGIC, 1, \
struct btrfs_ioctl_vol_args)
@@ -277,5 +286,7 @@ struct btrfs_ioctl_logical_ino_args {
struct btrfs_ioctl_ino_path_args)
#define BTRFS_IOC_LOGICAL_INO _IOWR(BTRFS_IOCTL_MAGIC, 36, \
struct btrfs_ioctl_ino_path_args)
+#define BTRFS_IOC_COMPR_SIZE _IOR(BTRFS_IOCTL_MAGIC, 51, \
+ struct btrfs_ioctl_compr_size_args)
#endif
--
1.7.7.3
--
To unsubscribe from this list: send the line "unsubscribe linux-btrfs" in
the body of a message to majord...@vger.kernel.org
More majordomo info at http://vger.kernel.org/majordomo-info.html
