[PATCH v3] btrfs-progs: Add recursive defrag using -r option

[PATCH v3] btrfs-progs: Add recursive defrag using -r option

[Frank Holton]

Add an option to defrag all files in a directory recursively.

Signed-off-by: Frank Holton <fholton@gmail.com>
---
v3: prefix globals with defrag
v2: switch to ftw amd callback

 cmds-filesystem.c |  156 ++++++++++++++++++++++++++++++++++++++---------------
 1 file changed, 113 insertions(+), 43 deletions(-)

diff --git a/cmds-filesystem.c b/cmds-filesystem.c
index f41a72a..44a224f 100644
--- a/cmds-filesystem.c
+++ b/cmds-filesystem.c
@@ -22,6 +22,8 @@
 #include <errno.h>
 #include <uuid/uuid.h>
 #include <ctype.h>
+#include <fcntl.h>
+#include <ftw.h>
 
 #include "kerncompat.h"
 #include "ctree.h"
@@ -265,7 +267,7 @@ static int cmd_show(int argc, char **argv)
 		fprintf(stderr, "ERROR: error %d while scanning\n", ret);
 		return 18;
 	}
-	
+
 	if(searchstart < argc)
 		search = argv[searchstart];
 
@@ -308,7 +310,7 @@ static int cmd_sync(int argc, char **argv)
 	e = errno;
 	close(fd);
 	if( res < 0 ){
-		fprintf(stderr, "ERROR: unable to fs-syncing '%s' - %s\n", 
+		fprintf(stderr, "ERROR: unable to fs-syncing '%s' - %s\n",
 			path, strerror(e));
 		return 16;
 	}
@@ -333,6 +335,7 @@ static const char * const cmd_defrag_usage[] = {
 	"Defragment a file or a directory",
 	"",
 	"-v             be verbose",
+	"-r             defragment files recursively",
 	"-c[zlib,lzo]   compress the file while defragmenting",
 	"-f             flush data to disk immediately after defragmenting",
 	"-s start       defragment only from byte onward",
@@ -341,6 +344,57 @@ static const char * const cmd_defrag_usage[] = {
 	NULL
 };
 
+static int do_defrag(int fd, int fancy_ioctl,
+			struct btrfs_ioctl_defrag_range_args *range)
+{
+	int ret;
+
+	if (!fancy_ioctl)
+		ret = ioctl(fd, BTRFS_IOC_DEFRAG, NULL);
+	else
+		ret = ioctl(fd, BTRFS_IOC_DEFRAG_RANGE, range);
+
+	return ret;
+}
+
+static int defrag_global_fancy_ioctl;
+static struct btrfs_ioctl_defrag_range_args defrag_global_range;
+static int defrag_global_verbose;
+static int defrag_global_errors;
+static int defrag_callback(const char *fpath, const struct stat *sb, int typeflag)
+{
+	int ret = 0;
+	int e = 0;
+	int fd = 0;
+
+	if (typeflag == FTW_F) {
+		if (defrag_global_verbose)
+				printf("%s\n", fpath);
+		fd = open(fpath, O_RDWR);
+		e = errno;
+		if (fd < 0)
+			goto error;
+		ret = do_defrag(fd, defrag_global_fancy_ioctl, &defrag_global_range);
+		e = errno;
+		close(fd);
+		if (ret && e == ENOTTY) {
+			fprintf(stderr, "ERROR: defrag range ioctl not "
+				"supported in this kernel, please try "
+				"without any options.\n");
+			defrag_global_errors++;
+			return ENOTTY;
+		}
+		if (ret)
+			goto error;
+	}
+	return 0;
+
+error:
+	fprintf(stderr, "ERROR: defrag failed on %s - %s\n", fpath, strerror(e));
+	defrag_global_errors++;
+	return 0;
+}
+
 static int cmd_defrag(int argc, char **argv)
 {
 	int fd;
@@ -349,17 +403,19 @@ static int cmd_defrag(int argc, char **argv)
 	u64 len = (u64)-1;
 	u32 thresh = 0;
 	int i;
-	int errors = 0;
+	int recursive = 0;
 	int ret = 0;
-	int verbose = 0;
-	int fancy_ioctl = 0;
 	struct btrfs_ioctl_defrag_range_args range;
-	int e=0;
+	int e = 0;
 	int compress_type = BTRFS_COMPRESS_NONE;
 
+	defrag_global_errors = 0;
+	defrag_global_verbose = 0;
+	defrag_global_errors = 0;
+	defrag_global_fancy_ioctl = 0;
 	optind = 1;
 	while(1) {
-		int c = getopt(argc, argv, "vc::fs:l:t:");
+		int c = getopt(argc, argv, "vrc::fs:l:t:");
 		if (c < 0)
 			break;
 
@@ -368,26 +424,29 @@ static int cmd_defrag(int argc, char **argv)
 			compress_type = BTRFS_COMPRESS_ZLIB;
 			if (optarg)
 				compress_type = parse_compress_type(optarg);
-			fancy_ioctl = 1;
+			defrag_global_fancy_ioctl = 1;
 			break;
 		case 'f':
 			flush = 1;
-			fancy_ioctl = 1;
+			defrag_global_fancy_ioctl = 1;
 			break;
 		case 'v':
-			verbose = 1;
+			defrag_global_verbose = 1;
 			break;
 		case 's':
 			start = parse_size(optarg);
-			fancy_ioctl = 1;
+			defrag_global_fancy_ioctl = 1;
 			break;
 		case 'l':
 			len = parse_size(optarg);
-			fancy_ioctl = 1;
+			defrag_global_fancy_ioctl = 1;
 			break;
 		case 't':
 			thresh = parse_size(optarg);
-			fancy_ioctl = 1;
+			defrag_global_fancy_ioctl = 1;
+			break;
+		case 'r':
+			recursive = 1;
 			break;
 		default:
 			usage(cmd_defrag_usage);
@@ -397,57 +456,68 @@ static int cmd_defrag(int argc, char **argv)
 	if (check_argc_min(argc - optind, 1))
 		usage(cmd_defrag_usage);
 
-	memset(&range, 0, sizeof(range));
-	range.start = start;
-	range.len = len;
-	range.extent_thresh = thresh;
+	memset(&defrag_global_range, 0, sizeof(range));
+	defrag_global_range.start = start;
+	defrag_global_range.len = len;
+	defrag_global_range.extent_thresh = thresh;
 	if (compress_type) {
-		range.flags |= BTRFS_DEFRAG_RANGE_COMPRESS;
-		range.compress_type = compress_type;
+		defrag_global_range.flags |= BTRFS_DEFRAG_RANGE_COMPRESS;
+		defrag_global_range.compress_type = compress_type;
 	}
 	if (flush)
-		range.flags |= BTRFS_DEFRAG_RANGE_START_IO;
+		defrag_global_range.flags |= BTRFS_DEFRAG_RANGE_START_IO;
 
 	for (i = optind; i < argc; i++) {
-		if (verbose)
-			printf("%s\n", argv[i]);
 		fd = open_file_or_dir(argv[i]);
 		if (fd < 0) {
-			fprintf(stderr, "failed to open %s\n", argv[i]);
+			fprintf(stderr, "ERROR: failed to open %s\n", argv[i]);
 			perror("open:");
-			errors++;
+			defrag_global_errors++;
 			continue;
 		}
-		if (!fancy_ioctl) {
-			ret = ioctl(fd, BTRFS_IOC_DEFRAG, NULL);
-			e=errno;
-		} else {
-			ret = ioctl(fd, BTRFS_IOC_DEFRAG_RANGE, &range);
-			if (ret && errno == ENOTTY) {
-				fprintf(stderr, "ERROR: defrag range ioctl not "
-					"supported in this kernel, please try "
-					"without any options.\n");
-				errors++;
-				close(fd);
-				break;
+		if (recursive) {
+			struct stat st;
+			fstat(fd, &st);
+			if (S_ISDIR(st.st_mode)) {
+				ret = ftw(argv[i], defrag_callback, 10);
+				if (ret == ENOTTY)
+					exit(1);
+				/* errors are handled in the callback */
+				ret = 0;
+			} else {
+				if (defrag_global_verbose)
+					printf("%s\n", argv[i]);
+				ret = do_defrag(fd, defrag_global_fancy_ioctl, &defrag_global_range);
+				e = errno;
 			}
+		} else {
+			if (defrag_global_verbose)
+				printf("%s\n", argv[i]);
+			ret = do_defrag(fd, defrag_global_fancy_ioctl, &defrag_global_range);
 			e = errno;
 		}
+		close(fd);
+		if (ret && e == ENOTTY) {
+			fprintf(stderr, "ERROR: defrag range ioctl not "
+				"supported in this kernel, please try "
+				"without any options.\n");
+			defrag_global_errors++;
+			break;
+		}
 		if (ret) {
 			fprintf(stderr, "ERROR: defrag failed on %s - %s\n",
 				argv[i], strerror(e));
-			errors++;
+			defrag_global_errors++;
 		}
-		close(fd);
 	}
-	if (verbose)
+	if (defrag_global_verbose)
 		printf("%s\n", BTRFS_BUILD_VERSION);
-	if (errors) {
-		fprintf(stderr, "total %d failures\n", errors);
+	if (defrag_global_errors) {
+		fprintf(stderr, "total %d failures\n", defrag_global_errors);
 		exit(1);
 	}
 
-	return errors;
+	return 0;
 }
 
 static const char * const cmd_resize_usage[] = {
@@ -489,7 +559,7 @@ static int cmd_resize(int argc, char **argv)
 	e = errno;
 	close(fd);
 	if( res < 0 ){
-		fprintf(stderr, "ERROR: unable to resize '%s' - %s\n", 
+		fprintf(stderr, "ERROR: unable to resize '%s' - %s\n",
 			path, strerror(e));
 		return 30;
 	}
-- 
1.7.9.5

Re: [PATCH v3] btrfs-progs: Add recursive defrag using -r option

[David Sterba]

On Mon, Sep 23, 2013 at 03:18:17PM -0400, Frank Holton wrote:
> Add an option to defrag all files in a directory recursively.

I had this patch merged but still saw some problems. If there's eg. a
symlink to file on another filesystem, defrag fails with

"ERROR: defrag range ioctl not supported in this kernel, please try
without any options."

which does not match the error that occured.

In short, we have to use nftw and specify FTW_MOUNT (do not dive into
mountpoints) and FTW_PHYS (do not follow symlinks). Fixed and added to
integration. Please write the corresponding bits of manpage and send a
patch.

thanks,
david