xfs_scrub: fstrim the free areas if there are no errors on the filesystem

If the filesystem scan comes out clean or fixes all the problems, call
fstrim to clean out the free areas (if it's an ssd/thinp/whatever).

Signed-off-by: Darrick J. Wong <darrick.wong@oracle.com>
Reviewed-by: Eric Sandeen <sandeen@redhat.com>
Signed-off-by: Eric Sandeen <sandeen@sandeen.net>

7 files changed, 131 insertions, 2 deletions

diff --git a/man/man8/xfs_scrub.8 b/man/man8/xfs_scrub.8
index c9df7d6bb3..b6e156057c 100644
--- a/man/man8/xfs_scrub.8
+++ b/man/man8/xfs_scrub.8
@@ -63,6 +63,9 @@ If
 is given, no action is taken if errors are found; this is the default
 behavior.
 .TP
+.B \-k
+Do not call FITRIM on the free space.
+.TP
 .BI \-m " file"
 Search this file for mounted filesystems instead of /etc/mtab.
 .TP
diff --git a/scrub/Makefile b/scrub/Makefile
index fd266244b0..91f99fff11 100644
--- a/scrub/Makefile
+++ b/scrub/Makefile
@@ -41,6 +41,7 @@ inodes.c \
 phase1.c \
 phase2.c \
 phase3.c \
+phase4.c \
 phase5.c \
 phase6.c \
 phase7.c \
diff --git a/scrub/phase4.c b/scrub/phase4.c
new file mode 100644
index 0000000000..31211f6945
--- /dev/null
+++ b/scrub/phase4.c
@@ -0,0 +1,79 @@
+/*
+ * Copyright (C) 2018 Oracle.  All Rights Reserved.
+ *
+ * Author: Darrick J. Wong <darrick.wong@oracle.com>
+ *
+ * This program is free software; you can redistribute it and/or
+ * modify it under the terms of the GNU General Public License
+ * as published by the Free Software Foundation; either version 2
+ * of the License, or (at your option) any later version.
+ *
+ * This program is distributed in the hope that it would 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 the Free Software Foundation,
+ * Inc.,  51 Franklin St, Fifth Floor, Boston, MA  02110-1301, USA.
+ */
+#include <stdio.h>
+#include <stdint.h>
+#include <stdbool.h>
+#include <dirent.h>
+#include <sys/types.h>
+#include <sys/stat.h>
+#include <sys/statvfs.h>
+#include "xfs.h"
+#include "xfs_fs.h"
+#include "list.h"
+#include "path.h"
+#include "workqueue.h"
+#include "xfs_scrub.h"
+#include "common.h"
+#include "scrub.h"
+#include "vfs.h"
+
+/* Phase 4: Repair filesystem. */
+
+/* Process all the action items. */
+static bool
+xfs_process_action_items(
+	struct scrub_ctx		*ctx)
+{
+	bool				moveon = true;
+
+	pthread_mutex_lock(&ctx->lock);
+	if (moveon && ctx->errors_found == 0 && want_fstrim)
+		fstrim(ctx);
+	pthread_mutex_unlock(&ctx->lock);
+
+	return moveon;
+}
+
+/* Fix everything that needs fixing. */
+bool
+xfs_repair_fs(
+	struct scrub_ctx		*ctx)
+{
+	return xfs_process_action_items(ctx);
+}
+
+/* Run the optimize-only phase if there are no errors. */
+bool
+xfs_optimize_fs(
+	struct scrub_ctx	*ctx)
+{
+	/*
+	 * In preen mode, corruptions are immediately recorded as errors,
+	 * so if there are any corruptions on the filesystem errors_found
+	 * will be non-zero and we won't do anything.
+	 */
+	if (ctx->errors_found) {
+		str_info(ctx, ctx->mntpoint,
+_("Errors found, please re-run with -y."));
+		return true;
+	}
+
+	return xfs_process_action_items(ctx);
+}
diff --git a/scrub/vfs.c b/scrub/vfs.c
index 3c0c2f3e25..e3c8e62c64 100644
--- a/scrub/vfs.c
+++ b/scrub/vfs.c
@@ -223,3 +223,26 @@ out_free:
 	free(sftd);
 	return false;
 }
+
+#ifndef FITRIM
+struct fstrim_range {
+	__u64 start;
+	__u64 len;
+	__u64 minlen;
+};
+#define FITRIM		_IOWR('X', 121, struct fstrim_range)	/* Trim */
+#endif
+
+/* Call FITRIM to trim all the unused space in a filesystem. */
+void
+fstrim(
+	struct scrub_ctx	*ctx)
+{
+	struct fstrim_range	range = {0};
+	int			error;
+
+	range.len = ULLONG_MAX;
+	error = ioctl(ctx->mnt_fd, FITRIM, &range);
+	if (error && errno != EOPNOTSUPP && errno != ENOTTY)
+		perror(_("fstrim"));
+}
diff --git a/scrub/vfs.h b/scrub/vfs.h
index 100eb18486..3305159e4d 100644
--- a/scrub/vfs.h
+++ b/scrub/vfs.h
@@ -28,4 +28,6 @@ typedef bool (*scan_fs_tree_dirent_fn)(struct scrub_ctx *, const char *,
 bool scan_fs_tree(struct scrub_ctx *ctx, scan_fs_tree_dir_fn dir_fn,
 		scan_fs_tree_dirent_fn dirent_fn, void *arg);
 
+void fstrim(struct scrub_ctx *ctx);
+
 #endif /* XFS_SCRUB_VFS_H_ */
diff --git a/scrub/xfs_scrub.c b/scrub/xfs_scrub.c
index f6f5f0d5f6..85fd893382 100644
--- a/scrub/xfs_scrub.c
+++ b/scrub/xfs_scrub.c
@@ -146,6 +146,9 @@ static bool			scrub_data;
 /* Size of a memory page. */
 long				page_size;
 
+/* Should we FSTRIM after a successful run? */
+bool				want_fstrim = true;
+
 #define SCRUB_RET_SUCCESS	(0)	/* no problems left behind */
 #define SCRUB_RET_CORRUPT	(1)	/* corruption remains on fs */
 #define SCRUB_RET_UNOPTIMIZED	(2)	/* fs could be optimized */
@@ -161,6 +164,7 @@ usage(void)
 	fprintf(stderr, _("  -a count     Stop after this many errors are found.\n"));
 	fprintf(stderr, _("  -b           Background mode.\n"));
 	fprintf(stderr, _("  -e behavior  What to do if errors are found.\n"));
+	fprintf(stderr, _("  -k           Do not FITRIM the free space.\n"));
 	fprintf(stderr, _("  -m path      Path to /etc/mtab.\n"));
 	fprintf(stderr, _("  -n           Dry run.  Do not modify anything.\n"));
 	fprintf(stderr, _("  -T           Display timing/usage information.\n"));
@@ -408,8 +412,19 @@ run_scrub_phases(
 	/* Run all phases of the scrub tool. */
 	for (phase = 1, sp = phases; sp->fn; sp++, phase++) {
 		/* Turn on certain phases if user said to. */
-		if (sp->fn == DATASCAN_DUMMY_FN && scrub_data)
+		if (sp->fn == DATASCAN_DUMMY_FN && scrub_data) {
 			sp->fn = xfs_scan_blocks;
+		} else if (sp->fn == REPAIR_DUMMY_FN) {
+			if (ctx->mode == SCRUB_MODE_PREEN) {
+				sp->descr = _("Optimize filesystem.");
+				sp->fn = xfs_optimize_fs;
+				sp->must_run = true;
+			} else if (ctx->mode == SCRUB_MODE_REPAIR) {
+				sp->descr = _("Repair filesystem.");
+				sp->fn = xfs_repair_fs;
+				sp->must_run = true;
+			}
+		}
 
 		/* Skip certain phases unless they're turned on. */
 		if (sp->fn == REPAIR_DUMMY_FN ||
@@ -469,7 +484,7 @@ main(
 	pthread_mutex_init(&ctx.lock, NULL);
 	ctx.mode = SCRUB_MODE_DEFAULT;
 	ctx.error_action = ERRORS_CONTINUE;
-	while ((c = getopt(argc, argv, "a:bde:m:nTvxVy")) != EOF) {
+	while ((c = getopt(argc, argv, "a:bde:km:nTvxVy")) != EOF) {
 		switch (c) {
 		case 'a':
 			ctx.max_errors = cvt_u64(optarg, 10);
@@ -497,6 +512,9 @@ main(
 				usage();
 			}
 			break;
+		case 'k':
+			want_fstrim = false;
+			break;
 		case 'm':
 			mtab = optarg;
 			break;
diff --git a/scrub/xfs_scrub.h b/scrub/xfs_scrub.h
index 91f457740a..47d63de57d 100644
--- a/scrub/xfs_scrub.h
+++ b/scrub/xfs_scrub.h
@@ -28,6 +28,7 @@ extern unsigned int		debug;
 extern int			nproc;
 extern bool			verbose;
 extern long			page_size;
+extern bool			want_fstrim;
 
 enum scrub_mode {
 	SCRUB_MODE_DRY_RUN,
@@ -105,5 +106,7 @@ bool xfs_scan_inodes(struct scrub_ctx *ctx);
 bool xfs_scan_connections(struct scrub_ctx *ctx);
 bool xfs_scan_blocks(struct scrub_ctx *ctx);
 bool xfs_scan_summary(struct scrub_ctx *ctx);
+bool xfs_repair_fs(struct scrub_ctx *ctx);
+bool xfs_optimize_fs(struct scrub_ctx *ctx);
 
 #endif /* XFS_SCRUB_XFS_SCRUB_H_ */