Add new defrag range ioctl that can also compress files on demand.

Makefile

@@ -17,7 +17,7 @@ bindir = $(prefix)/bin
 LIBS=-luuid
 
 progs = btrfsctl mkfs.btrfs btrfs-debug-tree btrfs-show btrfs-vol btrfsck \
-	btrfs-map-logical btrfs-list
+	btrfs-map-logical btrfs-list btrfs-defrag
 
 # make C=1 to enable sparse
 ifdef C
@@ -39,6 +39,9 @@ version:
 btrfs-list: $(objects) btrfs-list.o
 	gcc $(CFLAGS) -o btrfs-list btrfs-list.o $(objects) $(LDFLAGS) $(LIBS)
 
+btrfs-defrag: $(objects) btrfs-defrag.o
+	gcc $(CFLAGS) -o btrfs-defrag btrfs-defrag.o $(objects) $(LDFLAGS) $(LIBS)
+
 btrfsctl: $(objects) btrfsctl.o
 	gcc $(CFLAGS) -o btrfsctl btrfsctl.o $(objects) $(LDFLAGS) $(LIBS)
 

btrfs-defrag.c

@@ -0,0 +1,151 @@
+/*
+ * Copyright (C) 2010 Oracle.  All rights reserved.
+ *
+ * This program is free software; you can redistribute it and/or
+ * modify it under the terms of the GNU General Public
+ * License v2 as published by the Free Software Foundation.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
+ * General Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public
+ * License along with this program; if not, write to the
+ * Free Software Foundation, Inc., 59 Temple Place - Suite 330,
+ * Boston, MA 021110-1307, USA.
+ */
+
+#ifndef __CHECKER__
+#include <sys/ioctl.h>
+#include <sys/mount.h>
+#include "ioctl.h"
+#endif
+#include <stdio.h>
+#include <stdlib.h>
+#include <sys/types.h>
+#include <sys/stat.h>
+#include <fcntl.h>
+#include <ctype.h>
+#include <unistd.h>
+#include <dirent.h>
+#include <libgen.h>
+#include <getopt.h>
+#include "kerncompat.h"
+#include "ctree.h"
+#include "transaction.h"
+#include "utils.h"
+#include "version.h"
+
+static u64 parse_size(char *s)
+{
+	int len = strlen(s);
+	char c;
+	u64 mult = 1;
+
+	if (!isdigit(s[len - 1])) {
+		c = tolower(s[len - 1]);
+		switch (c) {
+		case 'g':
+			mult *= 1024;
+		case 'm':
+			mult *= 1024;
+		case 'k':
+			mult *= 1024;
+		case 'b':
+			break;
+		default:
+			fprintf(stderr, "Unknown size descriptor %c\n", c);
+			exit(1);
+		}
+		s[len - 1] = '\0';
+	}
+	return atoll(s) * mult;
+}
+
+static void print_usage(void)
+{
+	printf("usage: btrfs-defrag [-c] [-f] [-s start] [-l len] "
+	       "[-t threshold] file ...\n");
+	exit(1);
+}
+
+int main(int ac, char **av)
+{
+	int fd;
+	int compress = 0;
+	int flush = 0;
+	u64 start = 0;
+	u64 len = (u64)-1;
+	u32 thresh = 0;
+	int i;
+	int errors = 0;
+	int ret = 0;
+	int verbose = 0;
+	struct btrfs_ioctl_defrag_range_args range;
+
+	while(1) {
+		int c = getopt(ac, av, "vcfs:l:t:");
+		if (c < 0)
+			break;
+		switch(c) {
+		case 'c':
+			compress = 1;
+			break;
+		case 'f':
+			flush = 1;
+			break;
+		case 'v':
+			verbose = 1;
+			break;
+		case 's':
+			start = parse_size(optarg);
+			break;
+		case 'l':
+			len = parse_size(optarg);
+			break;
+		case 't':
+			thresh = parse_size(optarg);
+			break;
+		default:
+			print_usage();
+			return 1;
+		}
+	}
+	if (ac - optind == 0)
+		print_usage();
+
+	memset(&range, 0, sizeof(range));
+	range.start = start;
+	range.len = len;
+	range.extent_thresh = thresh;
+	if (compress)
+		range.flags |= BTRFS_DEFRAG_RANGE_COMPRESS;
+	if (flush)
+		range.flags |= BTRFS_DEFRAG_RANGE_START_IO;
+
+	for (i = optind; i < ac; i++) {
+		fd = open(av[i], O_RDWR);
+		if (fd < 0) {
+			fprintf(stderr, "failed to open %s\n", av[i]);
+			perror("open:");
+			errors++;
+			continue;
+		}
+		ret = ioctl(fd, BTRFS_IOC_DEFRAG_RANGE, &range);
+		if (ret) {
+			fprintf(stderr, "ioctl failed on %s ret %d\n",
+				av[i], ret);
+			errors++;
+		}
+		close(fd);
+	}
+	if (verbose)
+		printf("%s\n", BTRFS_BUILD_VERSION);
+	if (errors) {
+		fprintf(stderr, "total %d failures\n", errors);
+		exit(1);
+	}
+	return 0;
+}
+

ioctl.h

@@ -92,6 +92,34 @@ struct btrfs_ioctl_ino_lookup_args {
 	char name[BTRFS_INO_LOOKUP_PATH_MAX];
 };
 
+/* flags for the defrag range ioctl */
+#define BTRFS_DEFRAG_RANGE_COMPRESS 1
+#define BTRFS_DEFRAG_RANGE_START_IO 2
+
+struct btrfs_ioctl_defrag_range_args {
+	/* start of the defrag operation */
+	__u64 start;
+
+	/* number of bytes to defrag, use (u64)-1 to say all */
+	__u64 len;
+
+	/*
+	 * flags for the operation, which can include turning
+	 * on compression for this one defrag
+	 */
+	__u64 flags;
+
+	/*
+	 * any extent bigger than this will be considered
+	 * already defragged.  Use 0 to take the kernel default
+	 * Use 1 to say every single extent must be rewritten
+	 */
+	__u32 extent_thresh;
+
+	/* spare for later */
+	__u32 unused[5];
+};
+
 #define BTRFS_IOC_SNAP_CREATE _IOW(BTRFS_IOCTL_MAGIC, 1, \
 				   struct btrfs_ioctl_vol_args)
 #define BTRFS_IOC_DEFRAG _IOW(BTRFS_IOCTL_MAGIC, 2, \
@@ -118,10 +146,10 @@ struct btrfs_ioctl_ino_lookup_args {
 /* 13 is for CLONE_RANGE */
 #define BTRFS_IOC_SUBVOL_CREATE _IOW(BTRFS_IOCTL_MAGIC, 14, \
 				   struct btrfs_ioctl_vol_args)
-
 #define BTRFS_IOC_SNAP_DESTROY _IOW(BTRFS_IOCTL_MAGIC, 15, \
 				   struct btrfs_ioctl_vol_args)
-
+#define BTRFS_IOC_DEFRAG_RANGE _IOW(BTRFS_IOCTL_MAGIC, 16, \
+				struct btrfs_ioctl_defrag_range_args)
 #define BTRFS_IOC_TREE_SEARCH _IOWR(BTRFS_IOCTL_MAGIC, 17, \
 				   struct btrfs_ioctl_search_args)
 #define BTRFS_IOC_INO_LOOKUP _IOWR(BTRFS_IOCTL_MAGIC, 18, \