lk/linux-kernel-test
1
0
Fork 0
Code Issues Pull Requests Releases Wiki Activity

logfs: handle powerfail on NAND flash

Browse Source 
The write buffer may not have been written and may no longer be written
due to an interrupted write in the affected page.

Signed-off-by: Joern Engel <joern@logfs.org>
This commit is contained in:
Joern Engel
2010-05-07 19:38:40 +02:00
parent ccf31c10f1
commit 6f485b4187
4 changed files with 52 additions and 29 deletions
Download Patch File Download Diff File Expand all files Collapse all files

24
fs/logfs/dev_mtd.c
View File

@ -9,6 +9,7 @@
#include <linux/completion.h>
#include <linux/mount.h>
#include <linux/sched.h>
#include <linux/slab.h>
#define PAGE_OFS(ofs) ((ofs) & (PAGE_SIZE-1))
@ -126,7 +127,8 @@ static int mtd_readpage(void *_sb, struct page *page)
err = mtd_read(sb, page->index << PAGE_SHIFT, PAGE_SIZE,
page_address(page));
if (err == -EUCLEAN) {
if (err == -EUCLEAN || err == -EBADMSG) {
/* -EBADMSG happens regularly on power failures */
err = 0;
/* FIXME: force GC this segment */
}
@ -233,12 +235,32 @@ static void mtd_put_device(struct super_block *sb)
put_mtd_device(logfs_super(sb)->s_mtd);
}
static int mtd_can_write_buf(struct super_block *sb, u64 ofs)
{
struct logfs_super *super = logfs_super(sb);
void *buf;
int err;
buf = kmalloc(super->s_writesize, GFP_KERNEL);
if (!buf)
return -ENOMEM;
err = mtd_read(sb, ofs, super->s_writesize, buf);
if (err)
goto out;
if (memchr_inv(buf, 0xff, super->s_writesize))
err = -EIO;
kfree(buf);
out:
return err;
}
static const struct logfs_device_ops mtd_devops = {
.find_first_sb = mtd_find_first_sb,
.find_last_sb = mtd_find_last_sb,
.readpage = mtd_readpage,
.writeseg = mtd_writeseg,
.erase = mtd_erase,
.can_write_buf = mtd_can_write_buf,
.sync = mtd_sync,
.put_device = mtd_put_device,
};