proc: decouple proc from VFS with "struct proc_ops"

Currently core /proc code uses "struct file_operations" for custom hooks,
however, VFS doesn't directly call them.  Every time VFS expands
file_operations hook set, /proc code bloats for no reason.

Introduce "struct proc_ops" which contains only those hooks which /proc
allows to call into (open, release, read, write, ioctl, mmap, poll).  It
doesn't contain module pointer as well.

Save ~184 bytes per usage:

	add/remove: 26/26 grow/shrink: 1/4 up/down: 1922/-6674 (-4752)
	Function                                     old     new   delta
	sysvipc_proc_ops                               -      72     +72
				...
	config_gz_proc_ops                             -      72     +72
	proc_get_inode                               289     339     +50
	proc_reg_get_unmapped_area                   110     107      -3
	close_pdeo                                   227     224      -3
	proc_reg_open                                289     284      -5
	proc_create_data                              60      53      -7
	rt_cpu_seq_fops                              256       -    -256
				...
	default_affinity_proc_fops                   256       -    -256
	Total: Before=5430095, After=5425343, chg -0.09%

Link: http://lkml.kernel.org/r/20191225172228.GA13378@avx2
Signed-off-by: Alexey Dobriyan <adobriyan@gmail.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

1 files changed, 16 insertions, 16 deletions

diff --git a/fs/proc/proc_net.c b/fs/proc/proc_net.c
index 76ae278df1c4..4888c5224442 100644
--- a/fs/proc/proc_net.c
+++ b/fs/proc/proc_net.c
@@ -90,12 +90,12 @@ static int seq_release_net(struct inode *ino, struct file *f)
 	return 0;
 }
 
-static const struct file_operations proc_net_seq_fops = {
-	.open		= seq_open_net,
-	.read		= seq_read,
-	.write		= proc_simple_write,
-	.llseek		= seq_lseek,
-	.release	= seq_release_net,
+static const struct proc_ops proc_net_seq_ops = {
+	.proc_open	= seq_open_net,
+	.proc_read	= seq_read,
+	.proc_write	= proc_simple_write,
+	.proc_lseek	= seq_lseek,
+	.proc_release	= seq_release_net,
 };
 
 struct proc_dir_entry *proc_create_net_data(const char *name, umode_t mode,
@@ -108,7 +108,7 @@ struct proc_dir_entry *proc_create_net_data(const char *name, umode_t mode,
 	if (!p)
 		return NULL;
 	pde_force_lookup(p);
-	p->proc_fops = &proc_net_seq_fops;
+	p->proc_ops = &proc_net_seq_ops;
 	p->seq_ops = ops;
 	p->state_size = state_size;
 	return proc_register(parent, p);
@@ -152,7 +152,7 @@ struct proc_dir_entry *proc_create_net_data_write(const char *name, umode_t mode
 	if (!p)
 		return NULL;
 	pde_force_lookup(p);
-	p->proc_fops = &proc_net_seq_fops;
+	p->proc_ops = &proc_net_seq_ops;
 	p->seq_ops = ops;
 	p->state_size = state_size;
 	p->write = write;
@@ -183,12 +183,12 @@ static int single_release_net(struct inode *ino, struct file *f)
 	return single_release(ino, f);
 }
 
-static const struct file_operations proc_net_single_fops = {
-	.open		= single_open_net,
-	.read		= seq_read,
-	.write		= proc_simple_write,
-	.llseek		= seq_lseek,
-	.release	= single_release_net,
+static const struct proc_ops proc_net_single_ops = {
+	.proc_open	= single_open_net,
+	.proc_read	= seq_read,
+	.proc_write	= proc_simple_write,
+	.proc_lseek	= seq_lseek,
+	.proc_release	= single_release_net,
 };
 
 struct proc_dir_entry *proc_create_net_single(const char *name, umode_t mode,
@@ -201,7 +201,7 @@ struct proc_dir_entry *proc_create_net_single(const char *name, umode_t mode,
 	if (!p)
 		return NULL;
 	pde_force_lookup(p);
-	p->proc_fops = &proc_net_single_fops;
+	p->proc_ops = &proc_net_single_ops;
 	p->single_show = show;
 	return proc_register(parent, p);
 }
@@ -244,7 +244,7 @@ struct proc_dir_entry *proc_create_net_single_write(const char *name, umode_t mo
 	if (!p)
 		return NULL;
 	pde_force_lookup(p);
-	p->proc_fops = &proc_net_single_fops;
+	p->proc_ops = &proc_net_single_ops;
 	p->single_show = show;
 	p->write = write;
 	return proc_register(parent, p);