From 9272023b42febae7db1ec828016a980146095a83 Mon Sep 17 00:00:00 2001

From: Karel Zak <kzak@redhat.com>

Date: Thu, 2 Feb 2023 13:21:33 +0100

Subject: fstrim: backport entries de-duplication

Upstream: http://github.com/util-linux/util-linux/commit/9dbc073e4c58a56f68da8209df19789131446f5e

Upstream: http://github.com/util-linux/util-linux/commit/67f974d41d62c8b521fe81e1aac92562366f6a0a

Upstream: http://github.com/util-linux/util-linux/commit/20af6cee463cd6329b4f06db3282a09be942bd7a

Addresses: https://bugzilla.redhat.com/show_bug.cgi?id=2121699

Signed-off-by: Karel Zak <kzak@redhat.com>

---

 sys-utils/fstrim.c | 88 ++++++++++++++++++++++++++++++++++++++--------

 1 file changed, 74 insertions(+), 14 deletions(-)

diff --git a/sys-utils/fstrim.c b/sys-utils/fstrim.c

index 70870ef69..6aa523d72 100644

--- a/sys-utils/fstrim.c

+++ b/sys-utils/fstrim.c

@@ -35,6 +35,7 @@

 #include <sys/ioctl.h>

 #include <sys/stat.h>

+#include <sys/vfs.h>

 #include <linux/fs.h>

 #include "nls.h"

@@ -43,6 +44,7 @@

 #include "closestream.h"

 #include "pathnames.h"

 #include "sysfs.h"

+#include "statfs_magic.h"

 #include <libmount.h>

@@ -84,6 +86,7 @@ static int fstrim_filesystem(const char *path, struct fstrim_range *rangetpl,

 		goto done;

 	}

 	errno = 0;

+

 	if (ioctl(fd, FITRIM, &range)) {

 		rc = errno == EOPNOTSUPP || errno == ENOTTY ? 1 : -errno;

@@ -114,7 +117,7 @@ static int has_discard(const char *devname, struct sysfs_cxt *wholedisk)

 	struct sysfs_cxt cxt, *parent = NULL;

 	uint64_t dg = 0;

 	dev_t disk = 0, dev;

-	int rc;

+	int rc, rdonly = 0;

 	dev = sysfs_devname_to_devno(devname, NULL);

 	if (!dev)

@@ -139,11 +142,46 @@ static int has_discard(const char *devname, struct sysfs_cxt *wholedisk)

 	rc = sysfs_init(&cxt, dev, parent);

 	if (!rc)

 		rc = sysfs_read_u64(&cxt, "queue/discard_granularity", &dg;;

+	if (!rc)

+		sysfs_scanf(&cxt, "ro", "%d", &rdonly);

 	sysfs_deinit(&cxt);

-	return rc == 0 && dg > 0;

+	return rc == 0 && dg > 0 && rdonly == 0;

 }

+static int is_unwanted_fs(struct libmnt_fs *fs, const char *tgt)

+{

+	struct statfs vfs;

+	int fd, rc;

+

+	if (mnt_fs_is_pseudofs(fs))

+		return 1;

+	if (mnt_fs_is_netfs(fs))

+		return 1;

+	if (mnt_fs_is_swaparea(fs))

+		return 1;

+	if (mnt_fs_match_fstype(fs, "autofs"))

+		return 1;

+	if (mnt_fs_match_options(fs, "ro"))

+		return 1;

+

+	fd = open(tgt, O_PATH);

+	if (fd < 0)

+		return 1;

+	rc = fstatfs(fd, &vfs) != 0 || vfs.f_type == STATFS_AUTOFS_MAGIC;

+	close(fd);

+	if (rc)

+		return 1;

+

+	/* FITRIM on read-only filesystem can fail, and it can fail */

+	if (access(tgt, W_OK) != 0) {

+		if (errno == EROFS)

+			return 1;

+		if (errno == EACCES)

+			return 1;

+	}

+	return 0;

+}

 static int uniq_fs_target_cmp(

 		struct libmnt_table *tb __attribute__((__unused__)),

@@ -182,30 +220,38 @@ static int fstrim_all(struct fstrim_range *rangetpl, int verbose)

 	mnt_init_debug(0);

-	itr = mnt_new_iter(MNT_ITER_BACKWARD);

-	if (!itr)

-		err(MNT_EX_FAIL, _("failed to initialize libmount iterator"));

-

 	tab = mnt_new_table_from_file(_PATH_PROC_MOUNTINFO);

 	if (!tab)

 		err(MNT_EX_FAIL, _("failed to parse %s"), _PATH_PROC_MOUNTINFO);

+	if (mnt_table_is_empty(tab)) {

+		mnt_unref_table(tab);

+		return MNT_EX_SUCCESS;

+	}

+

 	/* de-duplicate by mountpoints */

 	mnt_table_uniq_fs(tab, 0, uniq_fs_target_cmp);

-	/* de-duplicate by source */

-	mnt_table_uniq_fs(tab, MNT_UNIQ_FORWARD, uniq_fs_source_cmp);

+	itr = mnt_new_iter(MNT_ITER_BACKWARD);

+	if (!itr)

+		err(MNT_EX_FAIL, _("failed to initialize libmount iterator"));

+	/* Remove useless entries and canonicalize the table */

 	while (mnt_table_next_fs(tab, itr, &fs) == 0) {

 		const char *src = mnt_fs_get_srcpath(fs),

 			   *tgt = mnt_fs_get_target(fs);

 		char *path;

 		int rc = 1;

-		if (!src || !tgt || *src != '/' ||

-		    mnt_fs_is_pseudofs(fs) ||

-		    mnt_fs_is_netfs(fs))

+		if (!tgt || is_unwanted_fs(fs, tgt)) {

+			mnt_table_remove_fs(tab, fs);

 			continue;

+		}

+

+		if (!src || *src != '/') {

+			mnt_table_remove_fs(tab, fs);

+			continue;

+		}

 		/* Is it really accessible mountpoint? Not all mountpoints are

 		 * accessible (maybe over mounted by another filesystem) */

@@ -213,11 +259,25 @@ static int fstrim_all(struct fstrim_range *rangetpl, int verbose)

 		if (path && strcmp(path, tgt) == 0)

 			rc = 0;

 		free(path);

-		if (rc)

+		if (rc) {

+			mnt_table_remove_fs(tab, fs);

 			continue;	/* overlaying mount */

+		}

-		if (!has_discard(src, &wholedisk))

+		if (!has_discard(src, &wholedisk)) {

+			mnt_table_remove_fs(tab, fs);

 			continue;

+		}

+	}

+

+	/* de-duplicate by source */

+	mnt_table_uniq_fs(tab, MNT_UNIQ_FORWARD, uniq_fs_source_cmp);

+

+	mnt_reset_iter(itr, MNT_ITER_BACKWARD);

+

+	/* Do FITRIM */

+	while (mnt_table_next_fs(tab, itr, &fs) == 0) {

+		const char *tgt = mnt_fs_get_target(fs);

 		cnt++;

 		/*

@@ -231,10 +291,10 @@ static int fstrim_all(struct fstrim_range *rangetpl, int verbose)

 		if (fstrim_filesystem(tgt, rangetpl, verbose) < 0)

 		       cnt_err++;

 	}

+	mnt_free_iter(itr);

 	sysfs_deinit(&wholedisk);

 	mnt_unref_table(tab);

-	mnt_free_iter(itr);

 	if (cnt && cnt == cnt_err)

 		return MNT_EX_FAIL;		/* all failed */

-- 

2.39.1