[PATCH 21/39] ext4: simplify procfs code

Christoph Hellwig
2018-04-19T12:41:22Z

Use remove_proc_subtree to remove the whole subtree on cleanup, and
unwind the registration loop into individual calls. Switch to use
proc_create_seq where applicable.

Signed-off-by: Christoph Hellwig <hch@lst.de>
---
fs/ext4/ext4.h | 2 +-
fs/ext4/mballoc.c | 29 ++++------------------------
fs/ext4/sysfs.c | 49 +++++++++--------------------------------------
3 files changed, 14 insertions(+), 66 deletions(-)

diff --git a/fs/ext4/ext4.h b/fs/ext4/ext4.h
index a42e71203e53..229ea4da6785 100644
--- a/fs/ext4/ext4.h
+++ b/fs/ext4/ext4.h
@@ -2390,7 +2390,7 @@ extern int ext4_init_inode_table(struct super_block *sb,
extern void ext4_end_bitmap_read(struct buffer_head *bh, int uptodate);

/* mballoc.c */
-extern const struct file_operations ext4_seq_mb_groups_fops;
+extern const struct seq_operations ext4_mb_seq_groups_ops;
extern long ext4_mb_stats;
extern long ext4_mb_max_to_scan;
extern int ext4_mb_init(struct super_block *);
diff --git a/fs/ext4/mballoc.c b/fs/ext4/mballoc.c
index 769a62708b1c..6884e81c1465 100644
--- a/fs/ext4/mballoc.c
+++ b/fs/ext4/mballoc.c
@@ -2254,7 +2254,7 @@ ext4_mb_regular_allocator(struct ext4_allocation_context *ac)

static void *ext4_mb_seq_groups_start(struct seq_file *seq, loff_t *pos)
{
- struct super_block *sb = seq->private;
+ struct super_block *sb = PDE_DATA(file_inode(seq->file));
ext4_group_t group;

if (*pos < 0 || *pos >= ext4_get_groups_count(sb))
@@ -2265,7 +2265,7 @@ static void *ext4_mb_seq_groups_start(struct seq_file *seq, loff_t *pos)

static void *ext4_mb_seq_groups_next(struct seq_file *seq, void *v, loff_t *pos)
{
- struct super_block *sb = seq->private;
+ struct super_block *sb = PDE_DATA(file_inode(seq->file));
ext4_group_t group;

++*pos;
@@ -2277,7 +2277,7 @@ static void *ext4_mb_seq_groups_next(struct seq_file *seq, void *v, loff_t *pos)

static int ext4_mb_seq_groups_show(struct seq_file *seq, void *v)
{
- struct super_block *sb = seq->private;
+ struct super_block *sb = PDE_DATA(file_inode(seq->file));
ext4_group_t group = (ext4_group_t) ((unsigned long) v);
int i;
int err, buddy_loaded = 0;
@@ -2330,34 +2330,13 @@ static void ext4_mb_seq_groups_stop(struct seq_file *seq, void *v)
{
}

-static const struct seq_operations ext4_mb_seq_groups_ops = {
+const struct seq_operations ext4_mb_seq_groups_ops = {
.start = ext4_mb_seq_groups_start,
.next = ext4_mb_seq_groups_next,
.stop = ext4_mb_seq_groups_stop,
.show = ext4_mb_seq_groups_show,
};

-static int ext4_mb_seq_groups_open(struct inode *inode, struct file *file)
-{
- struct super_block *sb = PDE_DATA(inode);
- int rc;
-
- rc = seq_open(file, &ext4_mb_seq_groups_ops);
- if (rc == 0) {
- struct seq_file *m = file->private_data;
- m->private = sb;
- }
- return rc;
-
-}
-
-const struct file_operations ext4_seq_mb_groups_fops = {
- .open = ext4_mb_seq_groups_open,
- .read = seq_read,
- .llseek = seq_lseek,
- .release = seq_release,
-};
-
static struct kmem_cache *get_groupinfo_cache(int blocksize_bits)
{
int cache_index = blocksize_bits - EXT4_MIN_BLOCK_LOG_SIZE;
diff --git a/fs/ext4/sysfs.c b/fs/ext4/sysfs.c
index 9ebd26c957c2..f34da0bb8f17 100644
--- a/fs/ext4/sysfs.c
+++ b/fs/ext4/sysfs.c
@@ -346,39 +346,9 @@ static struct kobject *ext4_root;

static struct kobject *ext4_feat;

-#define PROC_FILE_SHOW_DEFN(name) \
-static int name##_open(struct inode *inode, struct file *file) \
-{ \
- return single_open(file, ext4_seq_##name##_show, PDE_DATA(inode)); \
-} \
-\
-static const struct file_operations ext4_seq_##name##_fops = { \
- .open = name##_open, \
- .read = seq_read, \
- .llseek = seq_lseek, \
- .release = single_release, \
-}
-
-#define PROC_FILE_LIST(name) \
- { __stringify(name), &ext4_seq_##name##_fops }
-
-PROC_FILE_SHOW_DEFN(es_shrinker_info);
-PROC_FILE_SHOW_DEFN(options);
-
-static const struct ext4_proc_files {
- const char *name;
- const struct file_operations *fops;
-} proc_files[] = {
- PROC_FILE_LIST(options),
- PROC_FILE_LIST(es_shrinker_info),
- PROC_FILE_LIST(mb_groups),
- { NULL, NULL },
-};
-
int ext4_register_sysfs(struct super_block *sb)
{
struct ext4_sb_info *sbi = EXT4_SB(sb);
- const struct ext4_proc_files *p;
int err;

init_completion(&sbi->s_kobj_unregister);
@@ -392,11 +362,14 @@ int ext4_register_sysfs(struct super_block *sb)

if (ext4_proc_root)
sbi->s_proc = proc_mkdir(sb->s_id, ext4_proc_root);
-
if (sbi->s_proc) {
- for (p = proc_files; p->name; p++)
- proc_create_data(p->name, S_IRUGO, sbi->s_proc,
- p->fops, sb);
+ 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;
}
@@ -404,13 +377,9 @@ int ext4_register_sysfs(struct super_block *sb)
void ext4_unregister_sysfs(struct super_block *sb)
{
struct ext4_sb_info *sbi = EXT4_SB(sb);
- const struct ext4_proc_files *p;

- if (sbi->s_proc) {
- for (p = proc_files; p->name; p++)
- remove_proc_entry(p->name, sbi->s_proc);
- remove_proc_entry(sb->s_id, ext4_proc_root);
- }
+ if (sbi->s_proc)
+ remove_proc_subtree(sb->s_id, ext4_proc_root);
kobject_del(&sbi->s_kobj);
}

--
2.17.0

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