lkml.org 
[lkml]   [2001]   [Jul]   [8]   [last100]   RSS Feed
Views: [wrap][no wrap]   [headers]  [forward] 
 
Messages in this thread
Patch in this message
/
From
Date
SubjectRe: Memory region check in drivers/pcmcia/rsrc_mgr.c
Linus Torvalds writes:

> HOWEVER, you can change the resource checking to use the proper "parent
> resource" instead of using the root resource. I absolutely agree that
> using the root resource is wrong per se - it depends (incorrectly) on the
> fact that on all laptops the PCMCIA controller tends to be on the root
> bus.

I was able to do this more easily than I had expected, and there is a
(lightly-tested) patch below for comment and testing. The main thing
is that the routines in rsrc_mgr.c now basically need to get a handle
for the parent resource for the pcmcia socket controller that we are
concerned with at the moment. To get this I use the s->cap.cb_dev
field, which AFAICS gets set to the pci_dev for the controller for PCI
controllers and should be NULL for ISA controllers. If there is a
better way to get hold of the pci_dev let me know.

I have added a socket_info_t *s argument to validate_mem,
find_io_region and find_mem_region, so that we can get at
s->cap.cb_dev. The callers of these routines all have the
socket_info_t pointer readily to hand. We could pass in &s->cap or
s->cap.cb_dev instead, but passing s seems to be the easiest and most
generally useful option.

If s or s->cap.cb_dev is NULL the routines fall back to the old
behaviour, i.e. using ioport_resource or iomem_resource. Of course it
is possible that the ISA memory and I/O space could be a sub-node in
the ioport/mem_resource trees, and that we should be using those nodes
for ISA pcmcia controllers rather than ioport/mem_resource. If that
is so then we need to define new isa_ioport_resource and
isa_iomem_resource variables and set them in the architecture-specific
PCI code.

I also fixed the problem that Jeff Garzik pointed out, which is that
the existing code in find_io_region does a check_io_resource followed
by a request_region, without checking the return from request_region,
which is potentially racy (anyone for an SMP laptop? :). (And
find_mem_region does the analogous thing.) I replaced the pair of
calls with a single call to a new function, request_io_resource, which
attempts to allocate the region in the socket controller's parent
resource. Similarly there is a new request_mem_resource function
used in find_mem_region.

> Note that the CardBus side gets this all right - I assume that a 32-bit
> CardBus card with a PCI driver should work on your powerbook even without
> this patch, no?

I assume so, but I don't have any cardbus devices to test it with.

Regards,
Paul.

diff -urN linux/drivers/pcmcia/cistpl.c pmac/drivers/pcmcia/cistpl.c
--- linux/drivers/pcmcia/cistpl.c Thu Feb 22 14:25:19 2001
+++ pmac/drivers/pcmcia/cistpl.c Sun Jul 8 17:57:37 2001
@@ -264,11 +264,11 @@
(s->cis_mem.sys_start == 0)) {
int low = !(s->cap.features & SS_CAP_PAGE_REGS);
vs = s;
- validate_mem(cis_readable, checksum_match, low);
+ validate_mem(cis_readable, checksum_match, low, s);
s->cis_mem.sys_start = 0;
vs = NULL;
if (find_mem_region(&s->cis_mem.sys_start, s->cap.map_size,
- s->cap.map_size, low, "card services")) {
+ s->cap.map_size, low, "card services", s)) {
printk(KERN_NOTICE "cs: unable to map card memory!\n");
return CS_OUT_OF_RESOURCE;
}
diff -urN linux/drivers/pcmcia/cs.c pmac/drivers/pcmcia/cs.c
--- linux/drivers/pcmcia/cs.c Wed Jul 4 14:33:24 2001
+++ pmac/drivers/pcmcia/cs.c Sun Jul 8 17:57:36 2001
@@ -797,7 +797,7 @@
return 1;
for (i = 0; i < MAX_IO_WIN; i++) {
if (s->io[i].NumPorts == 0) {
- if (find_io_region(base, num, align, name) == 0) {
+ if (find_io_region(base, num, align, name, s) == 0) {
s->io[i].Attributes = attr;
s->io[i].BasePort = *base;
s->io[i].NumPorts = s->io[i].InUse = num;
@@ -809,7 +809,7 @@
/* Try to extend top of window */
try = s->io[i].BasePort + s->io[i].NumPorts;
if ((*base == 0) || (*base == try))
- if (find_io_region(&try, num, 0, name) == 0) {
+ if (find_io_region(&try, num, 0, name, s) == 0) {
*base = try;
s->io[i].NumPorts += num;
s->io[i].InUse += num;
@@ -818,7 +818,7 @@
/* Try to extend bottom of window */
try = s->io[i].BasePort - num;
if ((*base == 0) || (*base == try))
- if (find_io_region(&try, num, 0, name) == 0) {
+ if (find_io_region(&try, num, 0, name, s) == 0) {
s->io[i].BasePort = *base = try;
s->io[i].NumPorts += num;
s->io[i].InUse += num;
@@ -1960,7 +1960,7 @@
find_mem_region(&win->base, win->size, align,
(req->Attributes & WIN_MAP_BELOW_1MB) ||
!(s->cap.features & SS_CAP_PAGE_REGS),
- (*handle)->dev_info))
+ (*handle)->dev_info, s))
return CS_IN_USE;
(*handle)->state |= CLIENT_WIN_REQ(w);

diff -urN linux/drivers/pcmcia/cs_internal.h pmac/drivers/pcmcia/cs_internal.h
--- linux/drivers/pcmcia/cs_internal.h Fri Jan 5 09:51:32 2001
+++ pmac/drivers/pcmcia/cs_internal.h Sun Jul 8 17:55:00 2001
@@ -238,11 +238,11 @@

/* In rsrc_mgr */
void validate_mem(int (*is_valid)(u_long), int (*do_cksum)(u_long),
- int force_low);
+ int force_low, socket_info_t *s);
int find_io_region(ioaddr_t *base, ioaddr_t num, ioaddr_t align,
- char *name);
+ char *name, socket_info_t *s);
int find_mem_region(u_long *base, u_long num, u_long align,
- int force_low, char *name);
+ int force_low, char *name, socket_info_t *s);
int try_irq(u_int Attributes, int irq, int specific);
void undo_irq(u_int Attributes, int irq);
int adjust_resource_info(client_handle_t handle, adjust_t *adj);
diff -urN linux/drivers/pcmcia/rsrc_mgr.c pmac/drivers/pcmcia/rsrc_mgr.c
--- linux/drivers/pcmcia/rsrc_mgr.c Sat Mar 31 03:06:19 2001
+++ pmac/drivers/pcmcia/rsrc_mgr.c Sun Jul 8 17:56:30 2001
@@ -44,6 +44,7 @@
#include <linux/ioport.h>
#include <linux/timer.h>
#include <linux/proc_fs.h>
+#include <linux/pci.h>
#include <asm/irq.h>
#include <asm/io.h>

@@ -104,8 +105,78 @@

======================================================================*/

-#define check_io_resource(b,n) check_resource(&ioport_resource, (b), (n))
-#define check_mem_resource(b,n) check_resource(&iomem_resource, (b), (n))
+static struct resource *resource_parent(unsigned long b, unsigned long n,
+ int flags, socket_info_t *s)
+{
+ struct resource res;
+
+ if (s == NULL || s->cap.cb_dev == NULL) {
+ if (flags & IORESOURCE_MEM)
+ return &iomem_resource;
+ return &ioport_resource;
+ }
+ res.start = b;
+ res.end = b + n - 1;
+ res.flags = flags;
+ return pci_find_parent_resource(s->cap.cb_dev, &res);
+}
+
+static inline int check_io_resource(unsigned long b, unsigned long n,
+ socket_info_t *s)
+{
+ return check_resource(resource_parent(b, n, IORESOURCE_IO, s), b, n);
+}
+
+static inline int check_mem_resource(unsigned long b, unsigned long n,
+ socket_info_t *s)
+{
+ return check_resource(resource_parent(b, n, IORESOURCE_MEM, s), b, n);
+}
+
+static struct resource *make_resource(unsigned long b, unsigned long n,
+ int flags, char *name)
+{
+ struct resource *res = kmalloc(sizeof(*res), GFP_KERNEL);
+
+ if (res) {
+ memset(res, 0, sizeof(*res));
+ res->name = name;
+ res->start = b;
+ res->end = b + n - 1;
+ res->flags = flags | IORESOURCE_BUSY;
+ }
+ return res;
+}
+
+static int request_io_resource(unsigned long b, unsigned long n,
+ char *name, socket_info_t *s)
+{
+ struct resource *res = make_resource(b, n, IORESOURCE_IO, name);
+ struct resource *pr = resource_parent(b, n, IORESOURCE_IO, s);
+ int err = -ENOMEM;
+
+ if (res) {
+ err = request_resource(pr, res);
+ if (err)
+ kfree(res);
+ }
+ return err;
+}
+
+static int request_mem_resource(unsigned long b, unsigned long n,
+ char *name, socket_info_t *s)
+{
+ struct resource *res = make_resource(b, n, IORESOURCE_MEM, name);
+ struct resource *pr = resource_parent(b, n, IORESOURCE_MEM, s);
+ int err = -ENOMEM;
+
+ if (res) {
+ err = request_resource(pr, res);
+ if (err)
+ kfree(res);
+ }
+ return err;
+}

/*======================================================================

@@ -191,7 +262,7 @@
b = kmalloc(256, GFP_KERNEL);
memset(b, 0, 256);
for (i = base, most = 0; i < base+num; i += 8) {
- if (check_io_resource(i, 8))
+ if (check_io_resource(i, 8, NULL))
continue;
hole = inb(i);
for (j = 1; j < 8; j++)
@@ -204,7 +275,7 @@

bad = any = 0;
for (i = base; i < base+num; i += 8) {
- if (check_io_resource(i, 8))
+ if (check_io_resource(i, 8, NULL))
continue;
for (j = 0; j < 8; j++)
if (inb(i+j) != most) break;
@@ -244,7 +315,8 @@
======================================================================*/

static int do_mem_probe(u_long base, u_long num,
- int (*is_valid)(u_long), int (*do_cksum)(u_long))
+ int (*is_valid)(u_long), int (*do_cksum)(u_long),
+ socket_info_t *s)
{
u_long i, j, bad, fail, step;

@@ -255,13 +327,13 @@
for (i = j = base; i < base+num; i = j + step) {
if (!fail) {
for (j = i; j < base+num; j += step)
- if ((check_mem_resource(j, step) == 0) && is_valid(j))
+ if ((check_mem_resource(j, step, s) == 0) && is_valid(j))
break;
fail = ((i == base) && (j == base+num));
}
if (fail) {
for (j = i; j < base+num; j += 2*step)
- if ((check_mem_resource(j, 2*step) == 0) &&
+ if ((check_mem_resource(j, 2*step, s) == 0) &&
do_cksum(j) && do_cksum(j+step))
break;
}
@@ -280,7 +352,7 @@

static u_long inv_probe(int (*is_valid)(u_long),
int (*do_cksum)(u_long),
- resource_map_t *m)
+ resource_map_t *m, socket_info_t *s)
{
u_long ok;
if (m == &mem_db)
@@ -293,11 +365,11 @@
}
if (m->base < 0x100000)
return 0;
- return do_mem_probe(m->base, m->num, is_valid, do_cksum);
+ return do_mem_probe(m->base, m->num, is_valid, do_cksum, s);
}

void validate_mem(int (*is_valid)(u_long), int (*do_cksum)(u_long),
- int force_low)
+ int force_low, socket_info_t *s)
{
resource_map_t *m, *n;
static u_char order[] = { 0xd0, 0xe0, 0xc0, 0xf0 };
@@ -318,7 +390,7 @@
/* Only probe < 1 MB */
if (m->base >= 0x100000) continue;
if ((m->base | m->num) & 0xffff) {
- ok += do_mem_probe(m->base, m->num, is_valid, do_cksum);
+ ok += do_mem_probe(m->base, m->num, is_valid, do_cksum, s);
continue;
}
/* Special probe for 64K-aligned block */
@@ -328,7 +400,7 @@
if (ok >= mem_limit)
sub_interval(&mem_db, b, 0x10000);
else
- ok += do_mem_probe(b, 0x10000, is_valid, do_cksum);
+ ok += do_mem_probe(b, 0x10000, is_valid, do_cksum, s);
}
}
}
@@ -337,7 +409,7 @@
#else /* CONFIG_ISA */

void validate_mem(int (*is_valid)(u_long), int (*do_cksum)(u_long),
- int force_low)
+ int force_low, socket_info_t *s)
{
resource_map_t *m;
static int done = 0;
@@ -345,7 +417,7 @@
if (!probe_mem || done++)
return;
for (m = mem_db.next; m != &mem_db; m = m->next)
- if (do_mem_probe(m->base, m->num, is_valid, do_cksum))
+ if (do_mem_probe(m->base, m->num, is_valid, do_cksum, s))
return;
}

@@ -365,7 +437,7 @@
======================================================================*/

int find_io_region(ioaddr_t *base, ioaddr_t num, ioaddr_t align,
- char *name)
+ char *name, socket_info_t *s)
{
ioaddr_t try;
resource_map_t *m;
@@ -375,9 +447,8 @@
for (try = (try >= m->base) ? try : try+align;
(try >= m->base) && (try+num <= m->base+m->num);
try += align) {
- if (check_io_resource(try, num) == 0) {
+ if (request_io_resource(try, num, name, s) == 0) {
*base = try;
- request_region(try, num, name);
return 0;
}
if (!align) break;
@@ -387,7 +458,7 @@
}

int find_mem_region(u_long *base, u_long num, u_long align,
- int force_low, char *name)
+ int force_low, char *name, socket_info_t *s)
{
u_long try;
resource_map_t *m;
@@ -400,8 +471,7 @@
for (try = (try >= m->base) ? try : try+align;
(try >= m->base) && (try+num <= m->base+m->num);
try += align) {
- if (check_mem_resource(try, num) == 0) {
- request_mem_region(try, num, name);
+ if (request_mem_resource(try, num, name, s) == 0) {
*base = try;
return 0;
}
-
To unsubscribe from this list: send the line "unsubscribe linux-kernel" in
the body of a message to majordomo@vger.kernel.org
More majordomo info at http://vger.kernel.org/majordomo-info.html
Please read the FAQ at http://www.tux.org/lkml/
\
 
 \ /
  Last update: 2005-03-22 12:56    [W:0.061 / U:0.172 seconds]
©2003-2020 Jasper Spaans|hosted at Digital Ocean and TransIP|Read the blog|Advertise on this site