linux/fs/ext4/sysfs.c
Linus Torvalds a5adcfcad5 A large number of bug fixes and cleanups. One new feature to allow
users to more easily find the jbd2 journal thread for a particular
 ext4 file system.
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Merge tag 'ext4_for_linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tytso/ext4

Pull ext4 updates from Ted Ts'o:
 "A large number of bug fixes and cleanups.

  One new feature to allow users to more easily find the jbd2 journal
  thread for a particular ext4 file system"

* tag 'ext4_for_linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tytso/ext4: (25 commits)
  jbd2: jbd2_get_transaction does not need to return a value
  jbd2: fix invalid descriptor block checksum
  ext4: fix bigalloc cluster freeing when hole punching under load
  ext4: add sysfs attr /sys/fs/ext4/<disk>/journal_task
  ext4: Change debugging support help prefix from EXT4 to Ext4
  ext4: fix compile error when using BUFFER_TRACE
  jbd2: fix compile warning when using JBUFFER_TRACE
  ext4: fix some error pointer dereferences
  ext4: annotate more implicit fall throughs
  ext4: annotate implicit fall throughs
  ext4: don't update s_rev_level if not required
  jbd2: fold jbd2_superblock_csum_{verify,set} into their callers
  jbd2: fix race when writing superblock
  ext4: fix crash during online resizing
  ext4: disallow files with EXT4_JOURNAL_DATA_FL from EXT4_IOC_SWAP_BOOT
  ext4: add mask of ext4 flags to swap
  ext4: update quota information while swapping boot loader inode
  ext4: cleanup pagecache before swap i_data
  ext4: fix check of inode in swap_inode_boot_loader
  ext4: unlock unused_pages timely when doing writeback
  ...
2019-03-12 15:03:21 -07:00

464 lines
12 KiB
C

// SPDX-License-Identifier: GPL-2.0
/*
* linux/fs/ext4/sysfs.c
*
* Copyright (C) 1992, 1993, 1994, 1995
* Remy Card (card@masi.ibp.fr)
* Theodore Ts'o (tytso@mit.edu)
*
*/
#include <linux/time.h>
#include <linux/fs.h>
#include <linux/seq_file.h>
#include <linux/slab.h>
#include <linux/proc_fs.h>
#include "ext4.h"
#include "ext4_jbd2.h"
typedef enum {
attr_noop,
attr_delayed_allocation_blocks,
attr_session_write_kbytes,
attr_lifetime_write_kbytes,
attr_reserved_clusters,
attr_inode_readahead,
attr_trigger_test_error,
attr_first_error_time,
attr_last_error_time,
attr_feature,
attr_pointer_ui,
attr_pointer_atomic,
attr_journal_task,
} attr_id_t;
typedef enum {
ptr_explicit,
ptr_ext4_sb_info_offset,
ptr_ext4_super_block_offset,
} attr_ptr_t;
static const char proc_dirname[] = "fs/ext4";
static struct proc_dir_entry *ext4_proc_root;
struct ext4_attr {
struct attribute attr;
short attr_id;
short attr_ptr;
union {
int offset;
void *explicit_ptr;
} u;
};
static ssize_t session_write_kbytes_show(struct ext4_sb_info *sbi, char *buf)
{
struct super_block *sb = sbi->s_buddy_cache->i_sb;
if (!sb->s_bdev->bd_part)
return snprintf(buf, PAGE_SIZE, "0\n");
return snprintf(buf, PAGE_SIZE, "%lu\n",
(part_stat_read(sb->s_bdev->bd_part,
sectors[STAT_WRITE]) -
sbi->s_sectors_written_start) >> 1);
}
static ssize_t lifetime_write_kbytes_show(struct ext4_sb_info *sbi, char *buf)
{
struct super_block *sb = sbi->s_buddy_cache->i_sb;
if (!sb->s_bdev->bd_part)
return snprintf(buf, PAGE_SIZE, "0\n");
return snprintf(buf, PAGE_SIZE, "%llu\n",
(unsigned long long)(sbi->s_kbytes_written +
((part_stat_read(sb->s_bdev->bd_part,
sectors[STAT_WRITE]) -
EXT4_SB(sb)->s_sectors_written_start) >> 1)));
}
static ssize_t inode_readahead_blks_store(struct ext4_sb_info *sbi,
const char *buf, size_t count)
{
unsigned long t;
int ret;
ret = kstrtoul(skip_spaces(buf), 0, &t);
if (ret)
return ret;
if (t && (!is_power_of_2(t) || t > 0x40000000))
return -EINVAL;
sbi->s_inode_readahead_blks = t;
return count;
}
static ssize_t reserved_clusters_store(struct ext4_sb_info *sbi,
const char *buf, size_t count)
{
unsigned long long val;
ext4_fsblk_t clusters = (ext4_blocks_count(sbi->s_es) >>
sbi->s_cluster_bits);
int ret;
ret = kstrtoull(skip_spaces(buf), 0, &val);
if (ret || val >= clusters)
return -EINVAL;
atomic64_set(&sbi->s_resv_clusters, val);
return count;
}
static ssize_t trigger_test_error(struct ext4_sb_info *sbi,
const char *buf, size_t count)
{
int len = count;
if (!capable(CAP_SYS_ADMIN))
return -EPERM;
if (len && buf[len-1] == '\n')
len--;
if (len)
ext4_error(sbi->s_sb, "%.*s", len, buf);
return count;
}
static ssize_t journal_task_show(struct ext4_sb_info *sbi, char *buf)
{
if (!sbi->s_journal)
return snprintf(buf, PAGE_SIZE, "<none>\n");
return snprintf(buf, PAGE_SIZE, "%d\n",
task_pid_vnr(sbi->s_journal->j_task));
}
#define EXT4_ATTR(_name,_mode,_id) \
static struct ext4_attr ext4_attr_##_name = { \
.attr = {.name = __stringify(_name), .mode = _mode }, \
.attr_id = attr_##_id, \
}
#define EXT4_ATTR_FUNC(_name,_mode) EXT4_ATTR(_name,_mode,_name)
#define EXT4_ATTR_FEATURE(_name) EXT4_ATTR(_name, 0444, feature)
#define EXT4_ATTR_OFFSET(_name,_mode,_id,_struct,_elname) \
static struct ext4_attr ext4_attr_##_name = { \
.attr = {.name = __stringify(_name), .mode = _mode }, \
.attr_id = attr_##_id, \
.attr_ptr = ptr_##_struct##_offset, \
.u = { \
.offset = offsetof(struct _struct, _elname),\
}, \
}
#define EXT4_RO_ATTR_ES_UI(_name,_elname) \
EXT4_ATTR_OFFSET(_name, 0444, pointer_ui, ext4_super_block, _elname)
#define EXT4_RW_ATTR_SBI_UI(_name,_elname) \
EXT4_ATTR_OFFSET(_name, 0644, pointer_ui, ext4_sb_info, _elname)
#define EXT4_ATTR_PTR(_name,_mode,_id,_ptr) \
static struct ext4_attr ext4_attr_##_name = { \
.attr = {.name = __stringify(_name), .mode = _mode }, \
.attr_id = attr_##_id, \
.attr_ptr = ptr_explicit, \
.u = { \
.explicit_ptr = _ptr, \
}, \
}
#define ATTR_LIST(name) &ext4_attr_##name.attr
EXT4_ATTR_FUNC(delayed_allocation_blocks, 0444);
EXT4_ATTR_FUNC(session_write_kbytes, 0444);
EXT4_ATTR_FUNC(lifetime_write_kbytes, 0444);
EXT4_ATTR_FUNC(reserved_clusters, 0644);
EXT4_ATTR_OFFSET(inode_readahead_blks, 0644, inode_readahead,
ext4_sb_info, s_inode_readahead_blks);
EXT4_RW_ATTR_SBI_UI(inode_goal, s_inode_goal);
EXT4_RW_ATTR_SBI_UI(mb_stats, s_mb_stats);
EXT4_RW_ATTR_SBI_UI(mb_max_to_scan, s_mb_max_to_scan);
EXT4_RW_ATTR_SBI_UI(mb_min_to_scan, s_mb_min_to_scan);
EXT4_RW_ATTR_SBI_UI(mb_order2_req, s_mb_order2_reqs);
EXT4_RW_ATTR_SBI_UI(mb_stream_req, s_mb_stream_request);
EXT4_RW_ATTR_SBI_UI(mb_group_prealloc, s_mb_group_prealloc);
EXT4_RW_ATTR_SBI_UI(extent_max_zeroout_kb, s_extent_max_zeroout_kb);
EXT4_ATTR(trigger_fs_error, 0200, trigger_test_error);
EXT4_RW_ATTR_SBI_UI(err_ratelimit_interval_ms, s_err_ratelimit_state.interval);
EXT4_RW_ATTR_SBI_UI(err_ratelimit_burst, s_err_ratelimit_state.burst);
EXT4_RW_ATTR_SBI_UI(warning_ratelimit_interval_ms, s_warning_ratelimit_state.interval);
EXT4_RW_ATTR_SBI_UI(warning_ratelimit_burst, s_warning_ratelimit_state.burst);
EXT4_RW_ATTR_SBI_UI(msg_ratelimit_interval_ms, s_msg_ratelimit_state.interval);
EXT4_RW_ATTR_SBI_UI(msg_ratelimit_burst, s_msg_ratelimit_state.burst);
EXT4_RO_ATTR_ES_UI(errors_count, s_error_count);
EXT4_ATTR(first_error_time, 0444, first_error_time);
EXT4_ATTR(last_error_time, 0444, last_error_time);
EXT4_ATTR(journal_task, 0444, journal_task);
static unsigned int old_bump_val = 128;
EXT4_ATTR_PTR(max_writeback_mb_bump, 0444, pointer_ui, &old_bump_val);
static struct attribute *ext4_attrs[] = {
ATTR_LIST(delayed_allocation_blocks),
ATTR_LIST(session_write_kbytes),
ATTR_LIST(lifetime_write_kbytes),
ATTR_LIST(reserved_clusters),
ATTR_LIST(inode_readahead_blks),
ATTR_LIST(inode_goal),
ATTR_LIST(mb_stats),
ATTR_LIST(mb_max_to_scan),
ATTR_LIST(mb_min_to_scan),
ATTR_LIST(mb_order2_req),
ATTR_LIST(mb_stream_req),
ATTR_LIST(mb_group_prealloc),
ATTR_LIST(max_writeback_mb_bump),
ATTR_LIST(extent_max_zeroout_kb),
ATTR_LIST(trigger_fs_error),
ATTR_LIST(err_ratelimit_interval_ms),
ATTR_LIST(err_ratelimit_burst),
ATTR_LIST(warning_ratelimit_interval_ms),
ATTR_LIST(warning_ratelimit_burst),
ATTR_LIST(msg_ratelimit_interval_ms),
ATTR_LIST(msg_ratelimit_burst),
ATTR_LIST(errors_count),
ATTR_LIST(first_error_time),
ATTR_LIST(last_error_time),
ATTR_LIST(journal_task),
NULL,
};
/* Features this copy of ext4 supports */
EXT4_ATTR_FEATURE(lazy_itable_init);
EXT4_ATTR_FEATURE(batched_discard);
EXT4_ATTR_FEATURE(meta_bg_resize);
#ifdef CONFIG_FS_ENCRYPTION
EXT4_ATTR_FEATURE(encryption);
#endif
EXT4_ATTR_FEATURE(metadata_csum_seed);
static struct attribute *ext4_feat_attrs[] = {
ATTR_LIST(lazy_itable_init),
ATTR_LIST(batched_discard),
ATTR_LIST(meta_bg_resize),
#ifdef CONFIG_FS_ENCRYPTION
ATTR_LIST(encryption),
#endif
ATTR_LIST(metadata_csum_seed),
NULL,
};
static void *calc_ptr(struct ext4_attr *a, struct ext4_sb_info *sbi)
{
switch (a->attr_ptr) {
case ptr_explicit:
return a->u.explicit_ptr;
case ptr_ext4_sb_info_offset:
return (void *) (((char *) sbi) + a->u.offset);
case ptr_ext4_super_block_offset:
return (void *) (((char *) sbi->s_es) + a->u.offset);
}
return NULL;
}
static ssize_t __print_tstamp(char *buf, __le32 lo, __u8 hi)
{
return snprintf(buf, PAGE_SIZE, "%lld",
((time64_t)hi << 32) + le32_to_cpu(lo));
}
#define print_tstamp(buf, es, tstamp) \
__print_tstamp(buf, (es)->tstamp, (es)->tstamp ## _hi)
static ssize_t ext4_attr_show(struct kobject *kobj,
struct attribute *attr, char *buf)
{
struct ext4_sb_info *sbi = container_of(kobj, struct ext4_sb_info,
s_kobj);
struct ext4_attr *a = container_of(attr, struct ext4_attr, attr);
void *ptr = calc_ptr(a, sbi);
switch (a->attr_id) {
case attr_delayed_allocation_blocks:
return snprintf(buf, PAGE_SIZE, "%llu\n",
(s64) EXT4_C2B(sbi,
percpu_counter_sum(&sbi->s_dirtyclusters_counter)));
case attr_session_write_kbytes:
return session_write_kbytes_show(sbi, buf);
case attr_lifetime_write_kbytes:
return lifetime_write_kbytes_show(sbi, buf);
case attr_reserved_clusters:
return snprintf(buf, PAGE_SIZE, "%llu\n",
(unsigned long long)
atomic64_read(&sbi->s_resv_clusters));
case attr_inode_readahead:
case attr_pointer_ui:
if (!ptr)
return 0;
if (a->attr_ptr == ptr_ext4_super_block_offset)
return snprintf(buf, PAGE_SIZE, "%u\n",
le32_to_cpup(ptr));
else
return snprintf(buf, PAGE_SIZE, "%u\n",
*((unsigned int *) ptr));
case attr_pointer_atomic:
if (!ptr)
return 0;
return snprintf(buf, PAGE_SIZE, "%d\n",
atomic_read((atomic_t *) ptr));
case attr_feature:
return snprintf(buf, PAGE_SIZE, "supported\n");
case attr_first_error_time:
return print_tstamp(buf, sbi->s_es, s_first_error_time);
case attr_last_error_time:
return print_tstamp(buf, sbi->s_es, s_last_error_time);
case attr_journal_task:
return journal_task_show(sbi, buf);
}
return 0;
}
static ssize_t ext4_attr_store(struct kobject *kobj,
struct attribute *attr,
const char *buf, size_t len)
{
struct ext4_sb_info *sbi = container_of(kobj, struct ext4_sb_info,
s_kobj);
struct ext4_attr *a = container_of(attr, struct ext4_attr, attr);
void *ptr = calc_ptr(a, sbi);
unsigned long t;
int ret;
switch (a->attr_id) {
case attr_reserved_clusters:
return reserved_clusters_store(sbi, buf, len);
case attr_pointer_ui:
if (!ptr)
return 0;
ret = kstrtoul(skip_spaces(buf), 0, &t);
if (ret)
return ret;
if (a->attr_ptr == ptr_ext4_super_block_offset)
*((__le32 *) ptr) = cpu_to_le32(t);
else
*((unsigned int *) ptr) = t;
return len;
case attr_inode_readahead:
return inode_readahead_blks_store(sbi, buf, len);
case attr_trigger_test_error:
return trigger_test_error(sbi, buf, len);
}
return 0;
}
static void ext4_sb_release(struct kobject *kobj)
{
struct ext4_sb_info *sbi = container_of(kobj, struct ext4_sb_info,
s_kobj);
complete(&sbi->s_kobj_unregister);
}
static const struct sysfs_ops ext4_attr_ops = {
.show = ext4_attr_show,
.store = ext4_attr_store,
};
static struct kobj_type ext4_sb_ktype = {
.default_attrs = ext4_attrs,
.sysfs_ops = &ext4_attr_ops,
.release = ext4_sb_release,
};
static struct kobj_type ext4_feat_ktype = {
.default_attrs = ext4_feat_attrs,
.sysfs_ops = &ext4_attr_ops,
.release = (void (*)(struct kobject *))kfree,
};
static struct kobject *ext4_root;
static struct kobject *ext4_feat;
int ext4_register_sysfs(struct super_block *sb)
{
struct ext4_sb_info *sbi = EXT4_SB(sb);
int err;
init_completion(&sbi->s_kobj_unregister);
err = kobject_init_and_add(&sbi->s_kobj, &ext4_sb_ktype, ext4_root,
"%s", sb->s_id);
if (err) {
kobject_put(&sbi->s_kobj);
wait_for_completion(&sbi->s_kobj_unregister);
return err;
}
if (ext4_proc_root)
sbi->s_proc = proc_mkdir(sb->s_id, ext4_proc_root);
if (sbi->s_proc) {
proc_create_single_data("options", S_IRUGO, sbi->s_proc,
ext4_seq_options_show, sb);
proc_create_single_data("es_shrinker_info", S_IRUGO,
sbi->s_proc, ext4_seq_es_shrinker_info_show,
sb);
proc_create_seq_data("mb_groups", S_IRUGO, sbi->s_proc,
&ext4_mb_seq_groups_ops, sb);
}
return 0;
}
void ext4_unregister_sysfs(struct super_block *sb)
{
struct ext4_sb_info *sbi = EXT4_SB(sb);
if (sbi->s_proc)
remove_proc_subtree(sb->s_id, ext4_proc_root);
kobject_del(&sbi->s_kobj);
}
int __init ext4_init_sysfs(void)
{
int ret;
ext4_root = kobject_create_and_add("ext4", fs_kobj);
if (!ext4_root)
return -ENOMEM;
ext4_feat = kzalloc(sizeof(*ext4_feat), GFP_KERNEL);
if (!ext4_feat) {
ret = -ENOMEM;
goto root_err;
}
ret = kobject_init_and_add(ext4_feat, &ext4_feat_ktype,
ext4_root, "features");
if (ret)
goto feat_err;
ext4_proc_root = proc_mkdir(proc_dirname, NULL);
return ret;
feat_err:
kobject_put(ext4_feat);
ext4_feat = NULL;
root_err:
kobject_put(ext4_root);
ext4_root = NULL;
return ret;
}
void ext4_exit_sysfs(void)
{
kobject_put(ext4_feat);
ext4_feat = NULL;
kobject_put(ext4_root);
ext4_root = NULL;
remove_proc_entry(proc_dirname, NULL);
ext4_proc_root = NULL;
}