5.15-stable review patch. If anyone has any objections, please let me know.
------------------
From: Anand Jain <anand.jain@xxxxxxxxxx>
[ Upstream commit 020e5277583dc26d7a5322ff2d334c764ac1faa8 ]
Commit 2efc459d06f1 ("sysfs: Add sysfs_emit and sysfs_emit_at to format
sysfs out") merged in 5.10 introduced two new functions sysfs_emit() and
sysfs_emit_at() which are aware of the PAGE_SIZE limit of the output
buffer.
Use the above two new functions instead of scnprintf() and snprintf()
in various sysfs show().
Reviewed-by: Josef Bacik <josef@xxxxxxxxxxxxxx>
Signed-off-by: Anand Jain <anand.jain@xxxxxxxxxx>
Reviewed-by: David Sterba <dsterba@xxxxxxxx>
Signed-off-by: David Sterba <dsterba@xxxxxxxx>
Stable-dep-of: fca432e73db2 ("btrfs: sysfs: fix direct super block member reads")
Signed-off-by: Sasha Levin <sashal@xxxxxxxxxx>
---
fs/btrfs/sysfs.c | 93 +++++++++++++++++++++++-------------------------
1 file changed, 44 insertions(+), 49 deletions(-)
diff --git a/fs/btrfs/sysfs.c b/fs/btrfs/sysfs.c
index 93a9dfbc8d13..bc8d5b4c279e 100644
--- a/fs/btrfs/sysfs.c
+++ b/fs/btrfs/sysfs.c
@@ -177,7 +177,7 @@ static ssize_t btrfs_feature_attr_show(struct kobject *kobj,
} else
val = can_modify_feature(fa);
- return scnprintf(buf, PAGE_SIZE, "%d\n", val);
+ return sysfs_emit(buf, "%d\n", val);
}
static ssize_t btrfs_feature_attr_store(struct kobject *kobj,
@@ -333,7 +333,7 @@ static const struct attribute_group btrfs_feature_attr_group = {
static ssize_t rmdir_subvol_show(struct kobject *kobj,
struct kobj_attribute *ka, char *buf)
{
- return scnprintf(buf, PAGE_SIZE, "0\n");
+ return sysfs_emit(buf, "0\n");
}
BTRFS_ATTR(static_feature, rmdir_subvol, rmdir_subvol_show);
@@ -348,12 +348,12 @@ static ssize_t supported_checksums_show(struct kobject *kobj,
* This "trick" only works as long as 'enum btrfs_csum_type' has
* no holes in it
*/
- ret += scnprintf(buf + ret, PAGE_SIZE - ret, "%s%s",
- (i == 0 ? "" : " "), btrfs_super_csum_name(i));
+ ret += sysfs_emit_at(buf, ret, "%s%s", (i == 0 ? "" : " "),
+ btrfs_super_csum_name(i));
}
- ret += scnprintf(buf + ret, PAGE_SIZE - ret, "\n");
+ ret += sysfs_emit_at(buf, ret, "\n");
return ret;
}
BTRFS_ATTR(static_feature, supported_checksums, supported_checksums_show);
@@ -361,7 +361,7 @@ BTRFS_ATTR(static_feature, supported_checksums, supported_checksums_show);
static ssize_t send_stream_version_show(struct kobject *kobj,
struct kobj_attribute *ka, char *buf)
{
- return snprintf(buf, PAGE_SIZE, "%d\n", BTRFS_SEND_STREAM_VERSION);
+ return sysfs_emit(buf, "%d\n", BTRFS_SEND_STREAM_VERSION);
}
BTRFS_ATTR(static_feature, send_stream_version, send_stream_version_show);
@@ -381,9 +381,8 @@ static ssize_t supported_rescue_options_show(struct kobject *kobj,
int i;
for (i = 0; i < ARRAY_SIZE(rescue_opts); i++)
- ret += scnprintf(buf + ret, PAGE_SIZE - ret, "%s%s",
- (i ? " " : ""), rescue_opts[i]);
- ret += scnprintf(buf + ret, PAGE_SIZE - ret, "\n");
+ ret += sysfs_emit_at(buf, ret, "%s%s", (i ? " " : ""), rescue_opts[i]);
+ ret += sysfs_emit_at(buf, ret, "\n");
return ret;
}
BTRFS_ATTR(static_feature, supported_rescue_options,
@@ -397,10 +396,10 @@ static ssize_t supported_sectorsizes_show(struct kobject *kobj,
/* 4K sector size is also supported with 64K page size */
if (PAGE_SIZE == SZ_64K)
- ret += scnprintf(buf + ret, PAGE_SIZE - ret, "%u ", SZ_4K);
+ ret += sysfs_emit_at(buf, ret, "%u ", SZ_4K);
/* Only sectorsize == PAGE_SIZE is now supported */
- ret += scnprintf(buf + ret, PAGE_SIZE - ret, "%lu\n", PAGE_SIZE);
+ ret += sysfs_emit_at(buf, ret, "%lu\n", PAGE_SIZE);
return ret;
}
@@ -440,7 +439,7 @@ static ssize_t btrfs_discardable_bytes_show(struct kobject *kobj,
{
struct btrfs_fs_info *fs_info = discard_to_fs_info(kobj);
- return scnprintf(buf, PAGE_SIZE, "%lld\n",
+ return sysfs_emit(buf, "%lld\n",
atomic64_read(&fs_info->discard_ctl.discardable_bytes));
}
BTRFS_ATTR(discard, discardable_bytes, btrfs_discardable_bytes_show);
@@ -451,7 +450,7 @@ static ssize_t btrfs_discardable_extents_show(struct kobject *kobj,
{
struct btrfs_fs_info *fs_info = discard_to_fs_info(kobj);
- return scnprintf(buf, PAGE_SIZE, "%d\n",
+ return sysfs_emit(buf, "%d\n",
atomic_read(&fs_info->discard_ctl.discardable_extents));
}
BTRFS_ATTR(discard, discardable_extents, btrfs_discardable_extents_show);
@@ -462,8 +461,8 @@ static ssize_t btrfs_discard_bitmap_bytes_show(struct kobject *kobj,
{
struct btrfs_fs_info *fs_info = discard_to_fs_info(kobj);
- return scnprintf(buf, PAGE_SIZE, "%llu\n",
- fs_info->discard_ctl.discard_bitmap_bytes);
+ return sysfs_emit(buf, "%llu\n",
+ fs_info->discard_ctl.discard_bitmap_bytes);
}
BTRFS_ATTR(discard, discard_bitmap_bytes, btrfs_discard_bitmap_bytes_show);
@@ -473,7 +472,7 @@ static ssize_t btrfs_discard_bytes_saved_show(struct kobject *kobj,
{
struct btrfs_fs_info *fs_info = discard_to_fs_info(kobj);
- return scnprintf(buf, PAGE_SIZE, "%lld\n",
+ return sysfs_emit(buf, "%lld\n",
atomic64_read(&fs_info->discard_ctl.discard_bytes_saved));
}
BTRFS_ATTR(discard, discard_bytes_saved, btrfs_discard_bytes_saved_show);
@@ -484,8 +483,8 @@ static ssize_t btrfs_discard_extent_bytes_show(struct kobject *kobj,
{
struct btrfs_fs_info *fs_info = discard_to_fs_info(kobj);
- return scnprintf(buf, PAGE_SIZE, "%llu\n",
- fs_info->discard_ctl.discard_extent_bytes);
+ return sysfs_emit(buf, "%llu\n",
+ fs_info->discard_ctl.discard_extent_bytes);
}
BTRFS_ATTR(discard, discard_extent_bytes, btrfs_discard_extent_bytes_show);
@@ -495,8 +494,8 @@ static ssize_t btrfs_discard_iops_limit_show(struct kobject *kobj,
{
struct btrfs_fs_info *fs_info = discard_to_fs_info(kobj);
- return scnprintf(buf, PAGE_SIZE, "%u\n",
- READ_ONCE(fs_info->discard_ctl.iops_limit));
+ return sysfs_emit(buf, "%u\n",
+ READ_ONCE(fs_info->discard_ctl.iops_limit));
}
static ssize_t btrfs_discard_iops_limit_store(struct kobject *kobj,
@@ -526,8 +525,8 @@ static ssize_t btrfs_discard_kbps_limit_show(struct kobject *kobj,
{
struct btrfs_fs_info *fs_info = discard_to_fs_info(kobj);
- return scnprintf(buf, PAGE_SIZE, "%u\n",
- READ_ONCE(fs_info->discard_ctl.kbps_limit));
+ return sysfs_emit(buf, "%u\n",
+ READ_ONCE(fs_info->discard_ctl.kbps_limit));
}
static ssize_t btrfs_discard_kbps_limit_store(struct kobject *kobj,
@@ -556,8 +555,8 @@ static ssize_t btrfs_discard_max_discard_size_show(struct kobject *kobj,
{
struct btrfs_fs_info *fs_info = discard_to_fs_info(kobj);
- return scnprintf(buf, PAGE_SIZE, "%llu\n",
- READ_ONCE(fs_info->discard_ctl.max_discard_size));
+ return sysfs_emit(buf, "%llu\n",
+ READ_ONCE(fs_info->discard_ctl.max_discard_size));
}
static ssize_t btrfs_discard_max_discard_size_store(struct kobject *kobj,
@@ -630,7 +629,7 @@ static ssize_t btrfs_show_u64(u64 *value_ptr, spinlock_t *lock, char *buf)
val = *value_ptr;
if (lock)
spin_unlock(lock);
- return scnprintf(buf, PAGE_SIZE, "%llu\n", val);
+ return sysfs_emit(buf, "%llu\n", val);
}
static ssize_t global_rsv_size_show(struct kobject *kobj,
@@ -676,7 +675,7 @@ static ssize_t raid_bytes_show(struct kobject *kobj,
val += block_group->used;
}
up_read(&sinfo->groups_sem);
- return scnprintf(buf, PAGE_SIZE, "%llu\n", val);
+ return sysfs_emit(buf, "%llu\n", val);
}
/*
@@ -774,7 +773,7 @@ static ssize_t btrfs_label_show(struct kobject *kobj,
ssize_t ret;
spin_lock(&fs_info->super_lock);
- ret = scnprintf(buf, PAGE_SIZE, label[0] ? "%s\n" : "%s", label);
+ ret = sysfs_emit(buf, label[0] ? "%s\n" : "%s", label);
spin_unlock(&fs_info->super_lock);
return ret;
@@ -822,7 +821,7 @@ static ssize_t btrfs_nodesize_show(struct kobject *kobj,
{
struct btrfs_fs_info *fs_info = to_fs_info(kobj);
- return scnprintf(buf, PAGE_SIZE, "%u\n", fs_info->super_copy->nodesize);
+ return sysfs_emit(buf, "%u\n", fs_info->super_copy->nodesize);
}
BTRFS_ATTR(, nodesize, btrfs_nodesize_show);
@@ -832,8 +831,7 @@ static ssize_t btrfs_sectorsize_show(struct kobject *kobj,
{
struct btrfs_fs_info *fs_info = to_fs_info(kobj);
- return scnprintf(buf, PAGE_SIZE, "%u\n",
- fs_info->super_copy->sectorsize);
+ return sysfs_emit(buf, "%u\n", fs_info->super_copy->sectorsize);
}
BTRFS_ATTR(, sectorsize, btrfs_sectorsize_show);
@@ -843,7 +841,7 @@ static ssize_t btrfs_clone_alignment_show(struct kobject *kobj,
{
struct btrfs_fs_info *fs_info = to_fs_info(kobj);
- return scnprintf(buf, PAGE_SIZE, "%u\n", fs_info->super_copy->sectorsize);
+ return sysfs_emit(buf, "%u\n", fs_info->super_copy->sectorsize);
}
BTRFS_ATTR(, clone_alignment, btrfs_clone_alignment_show);
@@ -855,7 +853,7 @@ static ssize_t quota_override_show(struct kobject *kobj,
int quota_override;
quota_override = test_bit(BTRFS_FS_QUOTA_OVERRIDE, &fs_info->flags);
- return scnprintf(buf, PAGE_SIZE, "%d\n", quota_override);
+ return sysfs_emit(buf, "%d\n", quota_override);
}
static ssize_t quota_override_store(struct kobject *kobj,
@@ -893,8 +891,7 @@ static ssize_t btrfs_metadata_uuid_show(struct kobject *kobj,
{
struct btrfs_fs_info *fs_info = to_fs_info(kobj);
- return scnprintf(buf, PAGE_SIZE, "%pU\n",
- fs_info->fs_devices->metadata_uuid);
+ return sysfs_emit(buf, "%pU\n", fs_info->fs_devices->metadata_uuid);
}
BTRFS_ATTR(, metadata_uuid, btrfs_metadata_uuid_show);
@@ -905,9 +902,9 @@ static ssize_t btrfs_checksum_show(struct kobject *kobj,
struct btrfs_fs_info *fs_info = to_fs_info(kobj);
u16 csum_type = btrfs_super_csum_type(fs_info->super_copy);
- return scnprintf(buf, PAGE_SIZE, "%s (%s)\n",
- btrfs_super_csum_name(csum_type),
- crypto_shash_driver_name(fs_info->csum_shash));
+ return sysfs_emit(buf, "%s (%s)\n",
+ btrfs_super_csum_name(csum_type),
+ crypto_shash_driver_name(fs_info->csum_shash));
}
BTRFS_ATTR(, checksum, btrfs_checksum_show);
@@ -944,7 +941,7 @@ static ssize_t btrfs_exclusive_operation_show(struct kobject *kobj,
str = "UNKNOWN\n";
break;
}
- return scnprintf(buf, PAGE_SIZE, "%s", str);
+ return sysfs_emit(buf, "%s", str);
}
BTRFS_ATTR(, exclusive_operation, btrfs_exclusive_operation_show);
@@ -953,7 +950,7 @@ static ssize_t btrfs_generation_show(struct kobject *kobj,
{
struct btrfs_fs_info *fs_info = to_fs_info(kobj);
- return scnprintf(buf, PAGE_SIZE, "%llu\n", fs_info->generation);
+ return sysfs_emit(buf, "%llu\n", fs_info->generation);
}
BTRFS_ATTR(, generation, btrfs_generation_show);
@@ -1031,8 +1028,7 @@ static ssize_t btrfs_bg_reclaim_threshold_show(struct kobject *kobj,
struct btrfs_fs_info *fs_info = to_fs_info(kobj);
ssize_t ret;
- ret = scnprintf(buf, PAGE_SIZE, "%d\n",
- READ_ONCE(fs_info->bg_reclaim_threshold));
+ ret = sysfs_emit(buf, "%d\n", READ_ONCE(fs_info->bg_reclaim_threshold));
return ret;
}
@@ -1474,7 +1470,7 @@ static ssize_t btrfs_devinfo_in_fs_metadata_show(struct kobject *kobj,
val = !!test_bit(BTRFS_DEV_STATE_IN_FS_METADATA, &device->dev_state);
- return scnprintf(buf, PAGE_SIZE, "%d\n", val);
+ return sysfs_emit(buf, "%d\n", val);
}
BTRFS_ATTR(devid, in_fs_metadata, btrfs_devinfo_in_fs_metadata_show);
@@ -1487,7 +1483,7 @@ static ssize_t btrfs_devinfo_missing_show(struct kobject *kobj,
val = !!test_bit(BTRFS_DEV_STATE_MISSING, &device->dev_state);
- return scnprintf(buf, PAGE_SIZE, "%d\n", val);
+ return sysfs_emit(buf, "%d\n", val);
}
BTRFS_ATTR(devid, missing, btrfs_devinfo_missing_show);
@@ -1501,7 +1497,7 @@ static ssize_t btrfs_devinfo_replace_target_show(struct kobject *kobj,
val = !!test_bit(BTRFS_DEV_STATE_REPLACE_TGT, &device->dev_state);
- return scnprintf(buf, PAGE_SIZE, "%d\n", val);
+ return sysfs_emit(buf, "%d\n", val);
}
BTRFS_ATTR(devid, replace_target, btrfs_devinfo_replace_target_show);
@@ -1512,8 +1508,7 @@ static ssize_t btrfs_devinfo_scrub_speed_max_show(struct kobject *kobj,
struct btrfs_device *device = container_of(kobj, struct btrfs_device,
devid_kobj);
- return scnprintf(buf, PAGE_SIZE, "%llu\n",
- READ_ONCE(device->scrub_speed_max));
+ return sysfs_emit(buf, "%llu\n", READ_ONCE(device->scrub_speed_max));
}
static ssize_t btrfs_devinfo_scrub_speed_max_store(struct kobject *kobj,
@@ -1545,7 +1540,7 @@ static ssize_t btrfs_devinfo_writeable_show(struct kobject *kobj,
val = !!test_bit(BTRFS_DEV_STATE_WRITEABLE, &device->dev_state);
- return scnprintf(buf, PAGE_SIZE, "%d\n", val);
+ return sysfs_emit(buf, "%d\n", val);
}
BTRFS_ATTR(devid, writeable, btrfs_devinfo_writeable_show);
@@ -1556,14 +1551,14 @@ static ssize_t btrfs_devinfo_error_stats_show(struct kobject *kobj,
devid_kobj);
if (!device->dev_stats_valid)
- return scnprintf(buf, PAGE_SIZE, "invalid\n");
+ return sysfs_emit(buf, "invalid\n");
/*
* Print all at once so we get a snapshot of all values from the same
* time. Keep them in sync and in order of definition of
* btrfs_dev_stat_values.
*/
- return scnprintf(buf, PAGE_SIZE,
+ return sysfs_emit(buf,
"write_errs %d\n"
"read_errs %d\n"
"flush_errs %d\n"
--
2.39.5
