leandrof/linux
1
0
Fork 0
forked from Minki/linux
Code Issues Pull Requests Packages Projects Releases Wiki Activity

[MTD] mtdoops: Perform write operations in a workqueue

Browse Source 
Writing to the flash needs to be done in a workqueue. The console
write functions may be called in any context which can lead to
lockups otherwise.

Signed-off-by: Richard Purdie <rpurdie@rpsys.net>
Signed-off-by: David Woodhouse <dwmw2@infradead.org>
This commit is contained in:
Richard Purdie 2008-01-29 11:27:11 +00:00 committed by David Woodhouse
parent 2986bd2a33
commit 6ce0a856c1
1 changed files with 42 additions and 40 deletions
Show Stats Download Patch File Download Diff File Expand all files Collapse all files

82
drivers/mtd/mtdoops.c
View File

@ -32,9 +32,10 @@
#define OOPS_PAGE_SIZE 4096
static struct mtdoops_context {
struct mtdoops_context {
int mtd_index;
struct work_struct work;
struct work_struct work_erase;
struct work_struct work_write;
struct mtd_info *mtd;
int oops_pages;
int nextpage;
@ -87,7 +88,7 @@ static int mtdoops_erase_block(struct mtd_info *mtd, int offset)
return 0;
}
static int mtdoops_inc_counter(struct mtdoops_context *cxt)
static void mtdoops_inc_counter(struct mtdoops_context *cxt)
{
struct mtd_info *mtd = cxt->mtd;
size_t retlen;
@ -107,21 +108,26 @@ static int mtdoops_inc_counter(struct mtdoops_context *cxt)
printk(KERN_ERR "mtdoops: Read failure at %d (%td of 4 read)"
", err %d.\n", cxt->nextpage * OOPS_PAGE_SIZE,
retlen, ret);
return 1;
schedule_work(&cxt->work_erase);
return;
}
/* See if we need to erase the next block */
if (count != 0xffffffff)
return 1;
if (count != 0xffffffff) {
schedule_work(&cxt->work_erase);
return;
}
printk(KERN_DEBUG "mtdoops: Ready %d, %d (no erase)\n",
cxt->nextpage, cxt->nextcount);
cxt->ready = 1;
return 0;
}
static void mtdoops_prepare(struct mtdoops_context *cxt)
/* Scheduled work - when we can't proceed without erasing a block */
static void mtdoops_workfunc_erase(struct work_struct *work)
{
struct mtdoops_context *cxt =
container_of(work, struct mtdoops_context, work_erase);
struct mtd_info *mtd = cxt->mtd;
int i = 0, j, ret, mod;
@ -176,15 +182,31 @@ badblock:
goto badblock;
}
static void mtdoops_workfunc(struct work_struct *work)
static void mtdoops_workfunc_write(struct work_struct *work)
{
struct mtdoops_context *cxt =
container_of(work, struct mtdoops_context, work);
container_of(work, struct mtdoops_context, work_write);
struct mtd_info *mtd = cxt->mtd;
size_t retlen;
int ret;
mtdoops_prepare(cxt);
}
if (cxt->writecount < OOPS_PAGE_SIZE)
memset(cxt->oops_buf + cxt->writecount, 0xff,
OOPS_PAGE_SIZE - cxt->writecount);
static int find_next_position(struct mtdoops_context *cxt)
ret = mtd->write(mtd, cxt->nextpage * OOPS_PAGE_SIZE,
OOPS_PAGE_SIZE, &retlen, cxt->oops_buf);
cxt->writecount = 0;
if ((retlen != OOPS_PAGE_SIZE) || (ret < 0))
printk(KERN_ERR "mtdoops: Write failure at %d (%td of %d written), err %d.\n",
cxt->nextpage * OOPS_PAGE_SIZE, retlen, OOPS_PAGE_SIZE, ret);
mtdoops_inc_counter(cxt);
}
static void find_next_position(struct mtdoops_context *cxt)
{
struct mtd_info *mtd = cxt->mtd;
int ret, page, maxpos = 0;
@ -222,20 +244,19 @@ static int find_next_position(struct mtdoops_context *cxt)
cxt->ready = 1;
printk(KERN_DEBUG "mtdoops: Ready %d, %d (first init)\n",
cxt->nextpage, cxt->nextcount);
return 0;
return;
}
cxt->nextpage = maxpos;
cxt->nextcount = maxcount;
return mtdoops_inc_counter(cxt);
mtdoops_inc_counter(cxt);
}
static void mtdoops_notify_add(struct mtd_info *mtd)
{
struct mtdoops_context *cxt = &oops_cxt;
int ret;
if ((mtd->index != cxt->mtd_index) || cxt->mtd_index < 0)
return;
@ -249,9 +270,7 @@ static void mtdoops_notify_add(struct mtd_info *mtd)
cxt->mtd = mtd;
cxt->oops_pages = mtd->size / OOPS_PAGE_SIZE;
ret = find_next_position(cxt);
if (ret == 1)
mtdoops_prepare(cxt);
find_next_position(cxt);
printk(KERN_DEBUG "mtdoops: Attached to MTD device %d\n", mtd->index);
}
@ -271,31 +290,13 @@ static void mtdoops_console_sync(void)
{
struct mtdoops_context *cxt = &oops_cxt;
struct mtd_info *mtd = cxt->mtd;
size_t retlen;
int ret;
if (!cxt->ready || !mtd)
if (!cxt->ready || !mtd || cxt->writecount == 0)
return;
if (cxt->writecount == 0)
return;
if (cxt->writecount < OOPS_PAGE_SIZE)
memset(cxt->oops_buf + cxt->writecount, 0xff,
OOPS_PAGE_SIZE - cxt->writecount);
ret = mtd->write(mtd, cxt->nextpage * OOPS_PAGE_SIZE,
OOPS_PAGE_SIZE, &retlen, cxt->oops_buf);
cxt->ready = 0;
cxt->writecount = 0;
if ((retlen != OOPS_PAGE_SIZE) || (ret < 0))
printk(KERN_ERR "mtdoops: Write failure at %d (%td of %d written), err %d.\n",
cxt->nextpage * OOPS_PAGE_SIZE, retlen, OOPS_PAGE_SIZE, ret);
ret = mtdoops_inc_counter(cxt);
if (ret == 1)
schedule_work(&cxt->work);
schedule_work(&cxt->work_write);
}
static void
@ -365,7 +366,8 @@ static int __init mtdoops_console_init(void)
return -ENOMEM;
}
INIT_WORK(&cxt->work, mtdoops_workfunc);
INIT_WORK(&cxt->work_erase, mtdoops_workfunc_erase);
INIT_WORK(&cxt->work_write, mtdoops_workfunc_write);
register_console(&mtdoops_console);
register_mtd_user(&mtdoops_notifier);