[PATCH resend 1/2] btrfs-progs: fix kernel version parsing on some versions past 3.0

[PATCH resend 1/2] btrfs-progs: fix kernel version parsing on some versions past 3.0

[Adam Borowski]

The code fails if the third section is missing (like "4.18") or is followed
by anything but "." or "-".  This happens for example if we're not exactly
at a tag and CONFIG_LOCALVERSION_AUTO=n (which results in "4.18.5+").

Signed-off-by: Adam Borowski <kilobyte@angband.pl>
---
 fsfeatures.c | 5 +----
 1 file changed, 1 insertion(+), 4 deletions(-)

diff --git a/fsfeatures.c b/fsfeatures.c
index 13ad0308..68653739 100644
--- a/fsfeatures.c
+++ b/fsfeatures.c
@@ -216,11 +216,8 @@ u32 get_running_kernel_version(void)
 		return (u32)-1;
 	version |= atoi(tmp) << 8;
 	tmp = strtok_r(NULL, ".", &saveptr);
-	if (tmp) {
-		if (!string_is_numerical(tmp))
-			return (u32)-1;
+	if (tmp && string_is_numerical(tmp))
 		version |= atoi(tmp);
-	}
 
 	return version;
 }
-- 
2.20.1

[PATCH resend 2/2] btrfs-progs: defrag: open files RO on new enough kernels

[Adam Borowski]

Defragging an executable conflicts both way with it being run, resulting in
ETXTBSY.  This either makes defrag fail or prevents the program from being
executed.

Kernels 4.19-rc1 and later allow defragging files you could have possibly
opened rw, even if the passed descriptor is ro (commit 616d374efa23).

Signed-off-by: Adam Borowski <kilobyte@angband.pl>
---
 cmds-filesystem.c | 10 ++++++++--
 1 file changed, 8 insertions(+), 2 deletions(-)

diff --git a/cmds-filesystem.c b/cmds-filesystem.c
index b8beec13..0eb052dc 100644
--- a/cmds-filesystem.c
+++ b/cmds-filesystem.c
@@ -26,6 +26,7 @@
 #include <ftw.h>
 #include <mntent.h>
 #include <linux/limits.h>
+#include <linux/version.h>
 #include <getopt.h>
 
 #include <btrfsutil.h>
@@ -39,12 +40,14 @@
 #include "list_sort.h"
 #include "disk-io.h"
 #include "help.h"
+#include "fsfeatures.h"
 
 /*
  * for btrfs fi show, we maintain a hash of fsids we've already printed.
  * This way we don't print dups if a given FS is mounted more than once.
  */
 static struct seen_fsid *seen_fsid_hash[SEEN_FSID_HASH_SIZE] = {NULL,};
+static mode_t defrag_open_mode = O_RDONLY;
 
 static const char * const filesystem_cmd_group_usage[] = {
 	"btrfs filesystem [<group>] <command> [<args>]",
@@ -880,7 +883,7 @@ static int defrag_callback(const char *fpath, const struct stat *sb,
 	if ((typeflag == FTW_F) && S_ISREG(sb->st_mode)) {
 		if (defrag_global_verbose)
 			printf("%s\n", fpath);
-		fd = open(fpath, O_RDWR);
+		fd = open(fpath, defrag_open_mode);
 		if (fd < 0) {
 			goto error;
 		}
@@ -917,6 +920,9 @@ static int cmd_filesystem_defrag(int argc, char **argv)
 	int compress_type = BTRFS_COMPRESS_NONE;
 	DIR *dirstream;
 
+	if (get_running_kernel_version() < KERNEL_VERSION(4,19,0))
+		defrag_open_mode = O_RDWR;
+
 	/*
 	 * Kernel has a different default (256K) that is supposed to be safe,
 	 * but it does not defragment very well. The 32M will likely lead to
@@ -1017,7 +1023,7 @@ static int cmd_filesystem_defrag(int argc, char **argv)
 		int defrag_err = 0;
 
 		dirstream = NULL;
-		fd = open_file_or_dir(argv[i], &dirstream);
+		fd = open_file_or_dir3(argv[i], &dirstream, defrag_open_mode);
 		if (fd < 0) {
 			error("cannot open %s: %m", argv[i]);
 			ret = -errno;
-- 
2.20.1

Re: [PATCH resend 2/2] btrfs-progs: defrag: open files RO on new enough kernels

[David Sterba]

On Mon, Feb 25, 2019 at 07:16:44PM +0100, Adam Borowski wrote:
> Defragging an executable conflicts both way with it being run, resulting in
> ETXTBSY.  This either makes defrag fail or prevents the program from being
> executed.
> 
> Kernels 4.19-rc1 and later allow defragging files you could have possibly
> opened rw, even if the passed descriptor is ro (commit 616d374efa23).
> 
> Signed-off-by: Adam Borowski <kilobyte@angband.pl>

Applied, thanks.

Re: [PATCH resend 1/2] btrfs-progs: fix kernel version parsing on some versions past 3.0

[David Sterba]

On Mon, Feb 25, 2019 at 07:16:43PM +0100, Adam Borowski wrote:
> The code fails if the third section is missing (like "4.18") or is followed
> by anything but "." or "-".  This happens for example if we're not exactly
> at a tag and CONFIG_LOCALVERSION_AUTO=n (which results in "4.18.5+").
> 
> Signed-off-by: Adam Borowski <kilobyte@angband.pl>

Applied, thanks.