Commit b7072c63 authored by Alexey Dobriyan's avatar Alexey Dobriyan Committed by Russell King
Browse files

ARM: convert /proc/cpu/aligment to seq_file 



Convert code away from ->read_proc/->write_proc interfaces.  Switch to
proc_create()/proc_create_data() which makes addition of proc entries
reliable wrt NULL ->proc_fops, NULL ->data and so on.

Problem with ->read_proc et al is described here commit
786d7e16 "Fix rmmod/read/write races in
/proc entries"

This patch is part of an effort to remove the old simple procfs PAGE_SIZE
buffer interface.

Signed-off-by: default avatarAlexey Dobriyan <adobriyan@gmail.com>
Signed-off-by: default avatarAndrew Morton <akpm@linux-foundation.org>
Signed-off-by: default avatarRussell King <rmk+kernel@arm.linux.org.uk>
parent 4d736b5e

arch/arm/mm/alignment.c

+26 −27
Original line number Diff line number Diff line
@@ -17,6 +17,7 @@ 
#include <linux/errno.h>

#include <linux/string.h>

#include <linux/proc_fs.h>

#include <linux/seq_file.h>

#include <linux/init.h>

#include <linux/sched.h>

#include <linux/uaccess.h>
@@ -94,36 +95,29 @@ static const char *usermode_action[] = { 
	"signal+warn"

};



static int

proc_alignment_read(char *page, char **start, off_t off, int count, int *eof,

		    void *data)

static int alignment_proc_show(struct seq_file *m, void *v)

{

	char *p = page;

	int len;



	p += sprintf(p, "User:\t\t%lu\n", ai_user);

	p += sprintf(p, "System:\t\t%lu\n", ai_sys);

	p += sprintf(p, "Skipped:\t%lu\n", ai_skipped);

	p += sprintf(p, "Half:\t\t%lu\n", ai_half);

	p += sprintf(p, "Word:\t\t%lu\n", ai_word);

	seq_printf(m, "User:\t\t%lu\n", ai_user);

	seq_printf(m, "System:\t\t%lu\n", ai_sys);

	seq_printf(m, "Skipped:\t%lu\n", ai_skipped);

	seq_printf(m, "Half:\t\t%lu\n", ai_half);

	seq_printf(m, "Word:\t\t%lu\n", ai_word);

	if (cpu_architecture() >= CPU_ARCH_ARMv5TE)

		p += sprintf(p, "DWord:\t\t%lu\n", ai_dword);

	p += sprintf(p, "Multi:\t\t%lu\n", ai_multi);

	p += sprintf(p, "User faults:\t%i (%s)\n", ai_usermode,

		seq_printf(m, "DWord:\t\t%lu\n", ai_dword);

	seq_printf(m, "Multi:\t\t%lu\n", ai_multi);

	seq_printf(m, "User faults:\t%i (%s)\n", ai_usermode,

			usermode_action[ai_usermode]);



	len = (p - page) - off;

	if (len < 0)

		len = 0;



	*eof = (len <= count) ? 1 : 0;

	*start = page + off;

	return 0;

}



	return len;

static int alignment_proc_open(struct inode *inode, struct file *file)

{

	return single_open(file, alignment_proc_show, NULL);

}



static int proc_alignment_write(struct file *file, const char __user *buffer,

				unsigned long count, void *data)

static ssize_t alignment_proc_write(struct file *file, const char __user *buffer,

				    size_t count, loff_t *pos)

{

	char mode;
@@ -136,6 +130,13 @@ static int proc_alignment_write(struct file *file, const char __user *buffer, 
	return count;

}



static const struct file_operations alignment_proc_fops = {

	.open		= alignment_proc_open,

	.read		= seq_read,

	.llseek		= seq_lseek,

	.release	= single_release,

	.write		= alignment_proc_write,

};

#endif /* CONFIG_PROC_FS */



union offset_union {
@@ -901,12 +902,10 @@ static int __init alignment_init(void) 
#ifdef CONFIG_PROC_FS

	struct proc_dir_entry *res;



	res = create_proc_entry("cpu/alignment", S_IWUSR | S_IRUGO, NULL);

	res = proc_create("cpu/alignment", S_IWUSR | S_IRUGO, NULL,

			  &alignment_proc_fops);

	if (!res)

		return -ENOMEM;



	res->read_proc = proc_alignment_read;

	res->write_proc = proc_alignment_write;

#endif



	/*

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