ext4: move sysfs code from super.c to fs/ext4/sysfs.c
Also statically allocate the ext4_kset and ext4_feat objects, since we
only need exactly one of each, and it's simpler and less code if we
drop the dynamic allocation and deallocation when it's not needed.
Signed-off-by: Theodore Ts'o <tytso@mit.edu>
diff --git a/fs/ext4/sysfs.c b/fs/ext4/sysfs.c
new file mode 100644
index 0000000..9fdc21b
--- /dev/null
+++ b/fs/ext4/sysfs.c
@@ -0,0 +1,387 @@
+/*
+ * 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/proc_fs.h>
+
+#include "ext4.h"
+#include "ext4_jbd2.h"
+
+struct ext4_attr {
+ struct attribute attr;
+ ssize_t (*show)(struct ext4_attr *, struct ext4_sb_info *, char *);
+ ssize_t (*store)(struct ext4_attr *, struct ext4_sb_info *,
+ const char *, size_t);
+ union {
+ int offset;
+ int deprecated_val;
+ } u;
+};
+
+static int parse_strtoull(const char *buf,
+ unsigned long long max, unsigned long long *value)
+{
+ int ret;
+
+ ret = kstrtoull(skip_spaces(buf), 0, value);
+ if (!ret && *value > max)
+ ret = -EINVAL;
+ return ret;
+}
+
+static ssize_t delayed_allocation_blocks_show(struct ext4_attr *a,
+ struct ext4_sb_info *sbi,
+ char *buf)
+{
+ return snprintf(buf, PAGE_SIZE, "%llu\n",
+ (s64) EXT4_C2B(sbi,
+ percpu_counter_sum(&sbi->s_dirtyclusters_counter)));
+}
+
+static ssize_t session_write_kbytes_show(struct ext4_attr *a,
+ 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[1]) -
+ sbi->s_sectors_written_start) >> 1);
+}
+
+static ssize_t lifetime_write_kbytes_show(struct ext4_attr *a,
+ 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[1]) -
+ EXT4_SB(sb)->s_sectors_written_start) >> 1)));
+}
+
+static ssize_t inode_readahead_blks_store(struct ext4_attr *a,
+ 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 sbi_ui_show(struct ext4_attr *a,
+ struct ext4_sb_info *sbi, char *buf)
+{
+ unsigned int *ui = (unsigned int *) (((char *) sbi) + a->u.offset);
+
+ return snprintf(buf, PAGE_SIZE, "%u\n", *ui);
+}
+
+static ssize_t sbi_ui_store(struct ext4_attr *a,
+ struct ext4_sb_info *sbi,
+ const char *buf, size_t count)
+{
+ unsigned int *ui = (unsigned int *) (((char *) sbi) + a->u.offset);
+ unsigned long t;
+ int ret;
+
+ ret = kstrtoul(skip_spaces(buf), 0, &t);
+ if (ret)
+ return ret;
+ *ui = t;
+ return count;
+}
+
+static ssize_t es_ui_show(struct ext4_attr *a,
+ struct ext4_sb_info *sbi, char *buf)
+{
+
+ unsigned int *ui = (unsigned int *) (((char *) sbi->s_es) +
+ a->u.offset);
+
+ return snprintf(buf, PAGE_SIZE, "%u\n", *ui);
+}
+
+static ssize_t reserved_clusters_show(struct ext4_attr *a,
+ struct ext4_sb_info *sbi, char *buf)
+{
+ return snprintf(buf, PAGE_SIZE, "%llu\n",
+ (unsigned long long) atomic64_read(&sbi->s_resv_clusters));
+}
+
+static ssize_t reserved_clusters_store(struct ext4_attr *a,
+ 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);
+
+ if (parse_strtoull(buf, -1ULL, &val))
+ return -EINVAL;
+
+ if (val >= clusters)
+ return -EINVAL;
+
+ atomic64_set(&sbi->s_resv_clusters, val);
+ return count;
+}
+
+static ssize_t trigger_test_error(struct ext4_attr *a,
+ 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 sbi_deprecated_show(struct ext4_attr *a,
+ struct ext4_sb_info *sbi, char *buf)
+{
+ return snprintf(buf, PAGE_SIZE, "%d\n", a->u.deprecated_val);
+}
+
+#define EXT4_ATTR_OFFSET(_name,_mode,_show,_store,_elname) \
+static struct ext4_attr ext4_attr_##_name = { \
+ .attr = {.name = __stringify(_name), .mode = _mode }, \
+ .show = _show, \
+ .store = _store, \
+ .u = { \
+ .offset = offsetof(struct ext4_sb_info, _elname),\
+ }, \
+}
+
+#define EXT4_ATTR_OFFSET_ES(_name,_mode,_show,_store,_elname) \
+static struct ext4_attr ext4_attr_##_name = { \
+ .attr = {.name = __stringify(_name), .mode = _mode }, \
+ .show = _show, \
+ .store = _store, \
+ .u = { \
+ .offset = offsetof(struct ext4_super_block, _elname), \
+ }, \
+}
+
+#define EXT4_ATTR(name, mode, show, store) \
+static struct ext4_attr ext4_attr_##name = __ATTR(name, mode, show, store)
+
+#define EXT4_INFO_ATTR(name) EXT4_ATTR(name, 0444, NULL, NULL)
+#define EXT4_RO_ATTR(name) EXT4_ATTR(name, 0444, name##_show, NULL)
+#define EXT4_RW_ATTR(name) EXT4_ATTR(name, 0644, name##_show, name##_store)
+
+#define EXT4_RO_ATTR_ES_UI(name, elname) \
+ EXT4_ATTR_OFFSET_ES(name, 0444, es_ui_show, NULL, elname)
+#define EXT4_RW_ATTR_SBI_UI(name, elname) \
+ EXT4_ATTR_OFFSET(name, 0644, sbi_ui_show, sbi_ui_store, elname)
+
+#define ATTR_LIST(name) &ext4_attr_##name.attr
+#define EXT4_DEPRECATED_ATTR(_name, _val) \
+static struct ext4_attr ext4_attr_##_name = { \
+ .attr = {.name = __stringify(_name), .mode = 0444 }, \
+ .show = sbi_deprecated_show, \
+ .u = { \
+ .deprecated_val = _val, \
+ }, \
+}
+
+EXT4_RO_ATTR(delayed_allocation_blocks);
+EXT4_RO_ATTR(session_write_kbytes);
+EXT4_RO_ATTR(lifetime_write_kbytes);
+EXT4_RW_ATTR(reserved_clusters);
+EXT4_ATTR_OFFSET(inode_readahead_blks, 0644, sbi_ui_show,
+ inode_readahead_blks_store, 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_DEPRECATED_ATTR(max_writeback_mb_bump, 128);
+EXT4_RW_ATTR_SBI_UI(extent_max_zeroout_kb, s_extent_max_zeroout_kb);
+EXT4_ATTR(trigger_fs_error, 0200, NULL, 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_RO_ATTR_ES_UI(first_error_time, s_first_error_time);
+EXT4_RO_ATTR_ES_UI(last_error_time, s_last_error_time);
+
+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),
+ NULL,
+};
+
+/* Features this copy of ext4 supports */
+EXT4_INFO_ATTR(lazy_itable_init);
+EXT4_INFO_ATTR(batched_discard);
+EXT4_INFO_ATTR(meta_bg_resize);
+EXT4_INFO_ATTR(encryption);
+
+static struct attribute *ext4_feat_attrs[] = {
+ ATTR_LIST(lazy_itable_init),
+ ATTR_LIST(batched_discard),
+ ATTR_LIST(meta_bg_resize),
+ ATTR_LIST(encryption),
+ NULL,
+};
+
+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);
+
+ return a->show ? a->show(a, sbi, buf) : 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);
+
+ return a->store ? a->store(a, sbi, buf, len) : 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_ktype = {
+ .sysfs_ops = &ext4_attr_ops,
+};
+
+static struct kset ext4_kset = {
+ .kobj = {.ktype = &ext4_ktype},
+};
+
+static ssize_t ext4_feat_show(struct kobject *kobj,
+ struct attribute *attr, char *buf)
+{
+ return snprintf(buf, PAGE_SIZE, "supported\n");
+}
+
+/*
+ * We can not use ext4_attr_show/store because it relies on the kobject
+ * being embedded in the ext4_sb_info structure which is definitely not
+ * true in this case.
+ */
+static const struct sysfs_ops ext4_feat_ops = {
+ .show = ext4_feat_show,
+ .store = NULL,
+};
+
+static struct kobj_type ext4_feat_ktype = {
+ .default_attrs = ext4_feat_attrs,
+ .sysfs_ops = &ext4_feat_ops,
+};
+
+static struct kobject ext4_feat = {
+ .kset = &ext4_kset,
+};
+
+int ext4_register_sysfs(struct super_block *sb)
+{
+ struct ext4_sb_info *sbi = EXT4_SB(sb);
+
+ sbi->s_kobj.kset = &ext4_kset;
+ init_completion(&sbi->s_kobj_unregister);
+ return kobject_init_and_add(&sbi->s_kobj, &ext4_sb_ktype, NULL,
+ "%s", sb->s_id);
+}
+
+int __init ext4_init_sysfs(void)
+{
+ int ret;
+
+ kobject_set_name(&ext4_kset.kobj, "ext4");
+ ext4_kset.kobj.parent = fs_kobj;
+ ret = kset_register(&ext4_kset);
+ if (ret)
+ return ret;
+
+ ret = kobject_init_and_add(&ext4_feat, &ext4_feat_ktype,
+ NULL, "features");
+ if (ret)
+ kset_unregister(&ext4_kset);
+ return ret;
+}
+
+void ext4_exit_sysfs(void)
+{
+ kobject_put(&ext4_feat);
+ kset_unregister(&ext4_kset);
+}
+