Commit 5381e169 authored by Oleg Nesterov's avatar Oleg Nesterov Committed by Linus Torvalds
Browse files

proc: introduce proc_mem_open() 



Extract the mm_access() code from __mem_open() into the new helper,
proc_mem_open(), the next patch will add another caller.

Signed-off-by: default avatarOleg Nesterov <oleg@redhat.com>
Acked-by: default avatarKirill A. Shutemov <kirill.shutemov@linux.intel.com>
Acked-by: default avatarCyrill Gorcunov <gorcunov@openvz.org>
Cc: "Eric W. Biederman" <ebiederm@xmission.com>
Signed-off-by: default avatarAndrew Morton <akpm@linux-foundation.org>
Signed-off-by: default avatarLinus Torvalds <torvalds@linux-foundation.org>
parent 4db7d0ee

fs/proc/base.c

+21 −15
Original line number Diff line number Diff line
@@ -632,29 +632,35 @@ static const struct file_operations proc_single_file_operations = { 
	.release	= single_release,

};



static int __mem_open(struct inode *inode, struct file *file, unsigned int mode)

{

	struct task_struct *task = get_proc_task(file_inode(file));

	struct mm_struct *mm;



	if (!task)

		return -ESRCH;

struct mm_struct *proc_mem_open(struct inode *inode, unsigned int mode)

{

	struct task_struct *task = get_proc_task(inode);

	struct mm_struct *mm = ERR_PTR(-ESRCH);



	if (task) {

		mm = mm_access(task, mode);

		put_task_struct(task);



	if (IS_ERR(mm))

		return PTR_ERR(mm);



	if (mm) {

		if (!IS_ERR_OR_NULL(mm)) {

			/* ensure this mm_struct can't be freed */

			atomic_inc(&mm->mm_count);

			/* but do not pin its memory */

			mmput(mm);

		}

	}



	file->private_data = mm;

	return mm;

}



static int __mem_open(struct inode *inode, struct file *file, unsigned int mode)

{

	struct mm_struct *mm = proc_mem_open(inode, mode);



	if (IS_ERR(mm))

		return PTR_ERR(mm);



	file->private_data = mm;

	return 0;

}

fs/proc/internal.h

+2 −0
Original line number Diff line number Diff line
@@ -278,6 +278,8 @@ struct proc_maps_private { 
#endif

};



struct mm_struct *proc_mem_open(struct inode *inode, unsigned int mode);



extern const struct file_operations proc_pid_maps_operations;

extern const struct file_operations proc_tid_maps_operations;

extern const struct file_operations proc_pid_numa_maps_operations;

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