[PATCH 20/39] afs: simplify procfs code

Christoph Hellwig
2018-04-19T12:41:21Z

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/afs/proc.c | 134 ++++++--------------------------------------------
1 file changed, 15 insertions(+), 119 deletions(-)

diff --git a/fs/afs/proc.c b/fs/afs/proc.c
index 839a22280606..3aad32762989 100644
--- a/fs/afs/proc.c
+++ b/fs/afs/proc.c
@@ -62,7 +62,6 @@ static const struct file_operations afs_proc_rootcell_fops = {
.llseek = no_llseek,
};

-static int afs_proc_cell_volumes_open(struct inode *inode, struct file *file);
static void *afs_proc_cell_volumes_start(struct seq_file *p, loff_t *pos);
static void *afs_proc_cell_volumes_next(struct seq_file *p, void *v,
loff_t *pos);
@@ -76,15 +75,6 @@ static const struct seq_operations afs_proc_cell_volumes_ops = {
.show = afs_proc_cell_volumes_show,
};

-static const struct file_operations afs_proc_cell_volumes_fops = {
- .open = afs_proc_cell_volumes_open,
- .read = seq_read,
- .llseek = seq_lseek,
- .release = seq_release,
-};
-
-static int afs_proc_cell_vlservers_open(struct inode *inode,
- struct file *file);
static void *afs_proc_cell_vlservers_start(struct seq_file *p, loff_t *pos);
static void *afs_proc_cell_vlservers_next(struct seq_file *p, void *v,
loff_t *pos);
@@ -98,14 +88,6 @@ static const struct seq_operations afs_proc_cell_vlservers_ops = {
.show = afs_proc_cell_vlservers_show,
};

-static const struct file_operations afs_proc_cell_vlservers_fops = {
- .open = afs_proc_cell_vlservers_open,
- .read = seq_read,
- .llseek = seq_lseek,
- .release = seq_release,
-};
-
-static int afs_proc_servers_open(struct inode *inode, struct file *file);
static void *afs_proc_servers_start(struct seq_file *p, loff_t *pos);
static void *afs_proc_servers_next(struct seq_file *p, void *v,
loff_t *pos);
@@ -119,13 +101,6 @@ static const struct seq_operations afs_proc_servers_ops = {
.show = afs_proc_servers_show,
};

-static const struct file_operations afs_proc_servers_fops = {
- .open = afs_proc_servers_open,
- .read = seq_read,
- .llseek = seq_lseek,
- .release = seq_release,
-};
-
static int afs_proc_sysname_open(struct inode *inode, struct file *file);
static int afs_proc_sysname_release(struct inode *inode, struct file *file);
static void *afs_proc_sysname_start(struct seq_file *p, loff_t *pos);
@@ -152,7 +127,7 @@ static const struct file_operations afs_proc_sysname_fops = {
.write = afs_proc_sysname_write,
};

-static const struct file_operations afs_proc_stats_fops;
+static int afs_proc_stats_show(struct seq_file *m, void *v);

/*
* initialise the /proc/fs/afs/ directory
@@ -167,8 +142,8 @@ int afs_proc_init(struct afs_net *net)

if (!proc_create("cells", 0644, net->proc_afs, &afs_proc_cells_fops) ||
!proc_create("rootcell", 0644, net->proc_afs, &afs_proc_rootcell_fops) ||
- !proc_create("servers", 0644, net->proc_afs, &afs_proc_servers_fops) ||
- !proc_create("stats", 0644, net->proc_afs, &afs_proc_stats_fops) ||
+ !proc_create_seq("servers", 0644, net->proc_afs, &afs_proc_servers_ops) ||
+ !proc_create_single("stats", 0644, net->proc_afs, afs_proc_stats_show) ||
!proc_create("sysname", 0644, net->proc_afs, &afs_proc_sysname_fops))
goto error_tree;

@@ -196,16 +171,7 @@ void afs_proc_cleanup(struct afs_net *net)
*/
static int afs_proc_cells_open(struct inode *inode, struct file *file)
{
- struct seq_file *m;
- int ret;
-
- ret = seq_open(file, &afs_proc_cells_ops);
- if (ret < 0)
- return ret;
-
- m = file->private_data;
- m->private = PDE_DATA(inode);
- return 0;
+ return seq_open(file, &afs_proc_cells_ops);
}

/*
@@ -430,10 +396,11 @@ int afs_proc_cell_setup(struct afs_net *net, struct afs_cell *cell)
if (!dir)
goto error_dir;

- if (!proc_create_data("vlservers", 0, dir,
- &afs_proc_cell_vlservers_fops, cell) ||
- !proc_create_data("volumes", 0, dir,
- &afs_proc_cell_volumes_fops, cell))
+ if (!proc_create_seq_data("vlservers", 0, dir,
+ &afs_proc_cell_vlservers_ops, cell))
+ goto error_tree;
+ if (!proc_create_seq_data("volumes", 0, dir, &afs_proc_cell_volumes_ops,
+ cell))
goto error_tree;

_leave(" = 0");
@@ -458,29 +425,6 @@ void afs_proc_cell_remove(struct afs_net *net, struct afs_cell *cell)
_leave("");
}

-/*
- * open "/proc/fs/afs/<cell>/volumes" which provides a summary of extant cells
- */
-static int afs_proc_cell_volumes_open(struct inode *inode, struct file *file)
-{
- struct afs_cell *cell;
- struct seq_file *m;
- int ret;
-
- cell = PDE_DATA(inode);
- if (!cell)
- return -ENOENT;
-
- ret = seq_open(file, &afs_proc_cell_volumes_ops);
- if (ret < 0)
- return ret;
-
- m = file->private_data;
- m->private = cell;
-
- return 0;
-}
-
/*
* set up the iterator to start reading from the cells list and return the
* first item
@@ -488,7 +432,7 @@ static int afs_proc_cell_volumes_open(struct inode *inode, struct file *file)
static void *afs_proc_cell_volumes_start(struct seq_file *m, loff_t *_pos)
__acquires(cell->proc_lock)
{
- struct afs_cell *cell = m->private;
+ struct afs_cell *cell = PDE_DATA(file_inode(m->file));

_enter("cell=%p pos=%Ld", cell, *_pos);

@@ -502,7 +446,7 @@ static void *afs_proc_cell_volumes_start(struct seq_file *m, loff_t *_pos)
static void *afs_proc_cell_volumes_next(struct seq_file *p, void *v,
loff_t *_pos)
{
- struct afs_cell *cell = p->private;
+ struct afs_cell *cell = PDE_DATA(file_inode(p->file));

_enter("cell=%p pos=%Ld", cell, *_pos);
return seq_list_next(v, &cell->proc_volumes, _pos);
@@ -514,7 +458,7 @@ static void *afs_proc_cell_volumes_next(struct seq_file *p, void *v,
static void afs_proc_cell_volumes_stop(struct seq_file *p, void *v)
__releases(cell->proc_lock)
{
- struct afs_cell *cell = p->private;
+ struct afs_cell *cell = PDE_DATA(file_inode(p->file));

read_unlock(&cell->proc_lock);
}
@@ -530,7 +474,7 @@ static const char afs_vol_types[3][3] = {
*/
static int afs_proc_cell_volumes_show(struct seq_file *m, void *v)
{
- struct afs_cell *cell = m->private;
+ struct afs_cell *cell = PDE_DATA(file_inode(m->file));
struct afs_volume *vol = list_entry(v, struct afs_volume, proc_link);

/* Display header on line 1 */
@@ -546,30 +490,6 @@ static int afs_proc_cell_volumes_show(struct seq_file *m, void *v)
return 0;
}

-/*
- * open "/proc/fs/afs/<cell>/vlservers" which provides a list of volume
- * location server
- */
-static int afs_proc_cell_vlservers_open(struct inode *inode, struct file *file)
-{
- struct afs_cell *cell;
- struct seq_file *m;
- int ret;
-
- cell = PDE_DATA(inode);
- if (!cell)
- return -ENOENT;
-
- ret = seq_open(file, &afs_proc_cell_vlservers_ops);
- if (ret<0)
- return ret;
-
- m = file->private_data;
- m->private = cell;
-
- return 0;
-}
-
/*
* set up the iterator to start reading from the cells list and return the
* first item
@@ -578,7 +498,7 @@ static void *afs_proc_cell_vlservers_start(struct seq_file *m, loff_t *_pos)
__acquires(rcu)
{
struct afs_addr_list *alist;
- struct afs_cell *cell = m->private;
+ struct afs_cell *cell = PDE_DATA(file_inode(m->file));
loff_t pos = *_pos;

rcu_read_lock();
@@ -603,7 +523,7 @@ static void *afs_proc_cell_vlservers_next(struct seq_file *p, void *v,
loff_t *_pos)
{
struct afs_addr_list *alist;
- struct afs_cell *cell = p->private;
+ struct afs_cell *cell = PDE_DATA(file_inode(p->file));
loff_t pos;

alist = rcu_dereference(cell->vl_addrs);
@@ -643,15 +563,6 @@ static int afs_proc_cell_vlservers_show(struct seq_file *m, void *v)
return 0;
}

-/*
- * open "/proc/fs/afs/servers" which provides a summary of active
- * servers
- */
-static int afs_proc_servers_open(struct inode *inode, struct file *file)
-{
- return seq_open(file, &afs_proc_servers_ops);
-}
-
/*
* Set up the iterator to start reading from the server list and return the
* first item.
@@ -931,18 +842,3 @@ static int afs_proc_stats_show(struct seq_file *m, void *v)
atomic_long_read(&net->n_store_bytes));
return 0;
}
-
-/*
- * Open "/proc/fs/afs/stats" to allow reading of the stat counters.
- */
-static int afs_proc_stats_open(struct inode *inode, struct file *file)
-{
- return single_open(file, afs_proc_stats_show, NULL);
-}
-
-static const struct file_operations afs_proc_stats_fops = {
- .open = afs_proc_stats_open,
- .read = seq_read,
- .llseek = seq_lseek,
- .release = single_release,
-};
--
2.17.0

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