=====================
#!/bin/bash
BTRFS_ROOT=/
states=(
compress=zlib,datacow,datasum
compress=lzo,datacow,datasum
compress-force=zlib,datacow,datasum
compress-force=lzo,datacow,datasum
compress=no,nodatacow,nodatasum
compress=no,datacow,nodatasum
compress=no,datacow,datasum
)
options=(
compress
compress=zlib
compress=lzo
compress=no
compress=badopt
compress-force
compress-force=zlib
compress-force=lzo
compress-force=no
compress-force=badopt
nodatacow
datacow
nodatasum
datasum
)
for s in ${states[@]}; do
for o in ${options[@]}; do
# set initial state
echo initial: mount -o remount,$s
mount -o remount,$s ${BTRFS_ROOT}
# mount with each option
echo mount -o remount,$o
dmesg -C
mount -o remount,$o ${BTRFS_ROOT}
echo dmesg:
dmesg -t | perl -ne 'if(/^BTRFS info \(device .+?\): (.+)$/){print "\t$1\n"}'
echo -n 'mount options: '
grep -v rootfs /proc/mounts | \
awk "{if(\$2==\"${BTRFS_ROOT}\"){print \$4}}" | \
perl -ne '@a=split(/,/); for(@a){print "$_ " if(/^compress(-force)?=|nodata(cow|sum)$/)}'
echo
echo
done
done
=====================
Signed-off-by: Naohiro Aota <naota@elisp.net>
Signed-off-by: Satoru Takeuchi <takeuchi_satoru@jp.fujitsu.com>
---
fs/btrfs/super.c | 57 +++++++++++++++++++++++++++++++++++++++-----------------
1 file changed, 40 insertions(+), 17 deletions(-)
@@ -401,6 +401,7 @@ int btrfs_parse_options(struct btrfs_root *root, char *options)
char *compress_type;
bool compress_force = false;
bool compress = false;
+ unsigned long old_compress_type;
cache_gen = btrfs_super_cache_generation(root->fs_info->super_copy);
if (cache_gen)
@@ -486,40 +487,62 @@ int btrfs_parse_options(struct btrfs_root *root, char *options)
case Opt_compress:
case Opt_compress_type:
compress = true;
+ old_compress_type = info->compress_type;
if (token == Opt_compress ||
token == Opt_compress_force ||
strcmp(args[0].from, "zlib") == 0) {
compress_type = "zlib";
info->compress_type = BTRFS_COMPRESS_ZLIB;
- btrfs_set_opt(info->mount_opt, COMPRESS);
- btrfs_clear_opt(info->mount_opt, NODATACOW);
- btrfs_clear_opt(info->mount_opt, NODATASUM);
} else if (strcmp(args[0].from, "lzo") == 0) {
compress_type = "lzo";
info->compress_type = BTRFS_COMPRESS_LZO;
- btrfs_set_opt(info->mount_opt, COMPRESS);
- btrfs_clear_opt(info->mount_opt, NODATACOW);
- btrfs_clear_opt(info->mount_opt, NODATASUM);
btrfs_set_fs_incompat(info, COMPRESS_LZO);
} else if (strncmp(args[0].from, "no", 2) == 0) {
compress_type = "no";
- btrfs_clear_opt(info->mount_opt, COMPRESS);
- btrfs_clear_opt(info->mount_opt, FORCE_COMPRESS);
- compress_force = false;
+ compress = compress_force = false;
} else {
ret = -EINVAL;
goto out;
}
- if (compress_force) {
- btrfs_set_and_info(root, FORCE_COMPRESS,
- "force %s compression",
- compress_type);
- } else if (compress) {
- if (!btrfs_test_opt(root, COMPRESS))
+ if (compress_force || compress) {
+ const char *method = "", *setting = "";
+
+ if ((info->compress_type != old_compress_type) ||
+ (compress_force &&
+ !btrfs_test_opt(root, FORCE_COMPRESS)) ||
+ (!compress_force &&
+ btrfs_test_opt(root, FORCE_COMPRESS)) ||
+ (compress && !btrfs_test_opt(root, COMPRESS))) {
+ method = compress_force?"force":"use";
+ }
+
+ if (btrfs_test_opt(root, NODATACOW))
+ setting = ", setting datacow and datasum";
+ else if (btrfs_test_opt(root, NODATASUM))
+ setting = ", setting datasum";
+
+ if (strcmp(method, "") != 0) {
btrfs_info(root->fs_info,
- "btrfs: use %s compression",
- compress_type);
+ "%s %s compression%s",
+ method, compress_type,
+ setting);
+ }
+ if (compress_force) {
+ btrfs_set_opt(info->mount_opt,
+ FORCE_COMPRESS);
+ } else {
+ btrfs_clear_opt(info->mount_opt,
+ FORCE_COMPRESS);
+ }
+ btrfs_set_opt(info->mount_opt, COMPRESS);
+ btrfs_clear_opt(info->mount_opt, NODATACOW);
+ btrfs_clear_opt(info->mount_opt, NODATASUM);
+ } else {
+ btrfs_clear_and_info(root, COMPRESS,
+ "use no compression");
+ btrfs_clear_opt(info->mount_opt,
+ FORCE_COMPRESS);
}
break;
case Opt_ssd:
From: Naohiro Aota <naota@elisp.net> There are mutual exclusive mount options corresponding to compression options. If we set these options at once, we get improper messages and states, and a verbose message. * Improper states - We can't disable "compress forcing" with compress={zlib,lzo} mount option. ==== # mount -o remount,compress-force=zlib,compress=lzo [58852.210209] BTRFS info (device vda2): force zlib compression (We should see "use lzo compression" here) # mount | grep btrfs /dev/vda2 on / type btrfs (rw,relatime,seclabel,compress-force=lzo,space_cache) (We should also change "compress-force=lzo" to "compress=lzo") ==== * Improper messages - We don't see compression enabled message when we enables it after disabling it. ==== # mount -o remount,compress=no,compress=zlib; dmesg -c [ 4077.130625] BTRFS info (device vda2): btrfs: use no compression (We should see "use zlib compression" here) ==== - We don't see any message when we change compression type. ==== # mount -o remount,compress=zlib,compress=lzo (Since "BTRFS info" is at the beginning of this message, "btrfs: " is verbose and we don't need it.) ==== - We don't see datacow and/or datasum enabling message when we enable compression. ==== # mount -o remount,nodatacow,nodatasum,compress [58913.704536] BTRFS info (device vda2): setting nodatacow (We should see "use zlib compression, setting datacow and datasum" here) ==== ==== # mount -o remount,nodatasum,compress [58950.529392] BTRFS info (device vda2): setting nodatasum (We should see "use zlib compression, setting datasum" here) ==== * A verbose message - We see verbose "btrfs: " prefix on disabling compression. ==== # mount -o remount,compress=zlib,compress=no [58790.727788] BTRFS info (device vda2): btrfs: use no compression ("btrfs: " is verbose here. We don't need it, since we already state this is btrfs with "BTRFS info") ==== This commit solves all these problems. I separated the code in the following two parts: a) Parse the options. b) Set and clear flags of mount_opt and show proper messages. I've confirmed that this patch doesn't cause any regression by running the following script, which tests all combinations of corresponding mount options (compress, compress-force, datacow, and datasum). -- 1.8.3.1 -- To unsubscribe from this list: send the line "unsubscribe linux-btrfs" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html