Re: [PATCH] yenta resource allocation fix

Linus Torvalds
2001-08-29T13:51:26Z

On Wed, 29 Aug 2001, Andreas Bombe wrote:
>
> I have no idea why the 0xfff was in place. Or, on second thought, this
> might be to allocate memory space behind official end as slack? This
> would defy the end > start check then, anyway. Linus?

I've looked more at the issue.

0xfff is definitely right for memory windows and is generally right for
PCI-PCI bridges too - they cannot have IO or memory windows that are
anything but 4kB aligned.

But it turns out that the Yenta specification actually expanded on the
PCI-PCI bridge window specs for IO space - a Yenta bridge is supposed to
be able to handle IO windows at 4-byte granularity, not the 4kB a regular
PCI bridge does.

Does this alternate patch work for you?

Linus

------
diff -u --recursive --new-file pre2/linux/drivers/pcmcia/yenta.c linux/drivers/pcmcia/yenta.c
--- pre2/linux/drivers/pcmcia/yenta.c Wed Aug 29 06:20:01 2001
+++ linux/drivers/pcmcia/yenta.c Wed Aug 29 06:13:40 2001
@@ -702,6 +702,12 @@
u32 start, end;
u32 align, size, min, max;
unsigned offset;
+ unsigned mask;
+
+ /* The granularity of the memory limit is 4kB, on IO it's 4 bytes */
+ mask = ~0xfff;
+ if (type & IORESOURCE_IO)
+ mask = ~3;

offset = 0x1c + 8*nr;
bus = socket->dev->subordinate;
@@ -715,8 +721,8 @@
if (!root)
return;

- start = config_readl(socket, offset);
- end = config_readl(socket, offset+4) | 0xfff;
+ start = config_readl(socket, offset) & mask;
+ end = config_readl(socket, offset+4) | ~mask;
if (start && end > start) {
res->start = start;
res->end = end;
diff -u --recursive --new-file pre2/linux/mm/vmscan.c linux/mm/vmscan.c
--- pre2/linux/mm/vmscan.c Wed Aug 15 02:37:07 2001
+++ linux/mm/vmscan.c Wed Aug 29 06:02:46 2001
@@ -818,10 +818,12 @@
#define GENERAL_SHORTAGE 4
static int do_try_to_free_pages(unsigned int gfp_mask, int user)
{
- /* Always walk at least the active queue when called */
- int shortage = INACTIVE_SHORTAGE;
+ int shortage = 0;
int maxtry;

+ /* Always walk at least the active queue when called */
+ refill_inactive_scan(DEF_PRIORITY);
+
maxtry = 1 << DEF_PRIORITY;
do {
/*
@@ -872,7 +874,8 @@
break;
} while (shortage);

- return !shortage;
+ /* Return success if we're not "totally short" */
+ return shortage != FREE_SHORTAGE | INACTIVE_SHORTAGE | GENERAL_SHORTAGE;
}

DECLARE_WAIT_QUEUE_HEAD(kswapd_wait);