hollalinux
/
linux-sg2042
mirror of https://github.com/sophgo/linux-riscv.git
1
0
Fork 0
Code Issues Packages Projects Releases Wiki Activity

/proc/kcore: fix stat.st_size 

Presently the size of /proc/kcore which can be read by 'ls -l' is 0.  But
it's not the correct value.

On x86-64, ls -l shows
 ... root root 140737486266368 2009-09-17 10:29 /proc/kcore
Then, 7FFFFFFE02000. This comes from vmalloc area's size.
(*) This shows "core" size, not  memory size.

This patch shows the size by updating "size" field in struct
proc_dir_entry.  Later, lookup routine will create inode and fill
inode->i_size based on this value.  Then, this has a problem.

 - Once inode is cached, inode->i_size will never be updated.

Then, this patch is not memory-hotplug-aware.

To update inode->i_size, we have to know dentry or inode.
But there is no way to lookup them by inside kernel. Hmmm....
Next patch will try it.

Signed-off-by: KAMEZAWA Hiroyuki <kamezawa.hiroyu@jp.fujitsu.com>
Acked-by: WANG Cong <xiyou.wangcong@gmail.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
This commit is contained in:
KAMEZAWA Hiroyuki 2009-09-22 16:45:51 -07:00 committed by Linus Torvalds
parent 90396f96b7
commit 678ad5d8aa
1 changed files with 5 additions and 1 deletions
Show Stats Download Patch File Download Diff File Expand all files Collapse all files

6
fs/proc/kcore.c
View File

@ -107,6 +107,8 @@ static void free_kclist_ents(struct list_head *head)
*/ */
static void __kcore_update_ram(struct list_head *list) static void __kcore_update_ram(struct list_head *list)
{ {
int nphdr;
size_t size;
struct kcore_list *tmp, *pos; struct kcore_list *tmp, *pos;
LIST_HEAD(garbage); LIST_HEAD(garbage);
@ -121,6 +123,7 @@ static void __kcore_update_ram(struct list_head *list)
} else } else
list_splice(list, &garbage); list_splice(list, &garbage);
kcore_need_update = 0; kcore_need_update = 0;
proc_root_kcore->size = get_kcore_size(&nphdr, &size);
write_unlock(&kclist_lock); write_unlock(&kclist_lock);
free_kclist_ents(&garbage); free_kclist_ents(&garbage);
@ -429,7 +432,8 @@ read_kcore(struct file *file, char __user *buffer, size_t buflen, loff_t *fpos)
unsigned long start; unsigned long start;
read_lock(&kclist_lock); read_lock(&kclist_lock);
proc_root_kcore->size = size = get_kcore_size(&nphdr, &elf_buflen); size = get_kcore_size(&nphdr, &elf_buflen);
if (buflen == 0 || *fpos >= size) { if (buflen == 0 || *fpos >= size) {
read_unlock(&kclist_lock); read_unlock(&kclist_lock);
return 0; return 0;