From: Jens Axboe <jens.axboe@oracle.com>
To: Benny Halevy <bhalevy@panasas.com>
Cc: linux-kernel@vger.kernel.org
Subject: Re: [PATCH 8/12] x86-64: update iommu/dma mapping functions to sg helpers
Date: Mon, 21 May 2007 09:13:22 +0200 [thread overview]
Message-ID: <20070521071322.GK14746@kernel.dk> (raw)
In-Reply-To: <465145BB.7050301@panasas.com>
On Mon, May 21 2007, Benny Halevy wrote:
> Jens Axboe wrote:
> > On Thu, May 10 2007, Benny Halevy wrote:
> >> @@ -411,12 +406,13 @@ int gart_map_sg(struct device *dev, struct scatterlist *sg, int nents, int dir)
> >> boundary and the new one doesn't have an offset. */
> >> if (!iommu_merge || !nextneed || !need || s->offset ||
> >> (ps->offset + ps->length) % PAGE_SIZE) {
> >> - if (dma_map_cont(sg, start, i, sg+out, pages,
> >> - need) < 0)
> >> + if (dma_map_cont(start_sg, i - start, sg+out,
> >> + pages, need) < 0)
> >> goto error;
> >> out++;
> >> pages = 0;
> >> - start = i;
> >> + start = i;
> >> + start_sg = s;
> >> }
> >> }
> >>
> >> @@ -424,7 +420,7 @@ int gart_map_sg(struct device *dev, struct scatterlist *sg, int nents, int dir)
> >> pages += to_pages(s->offset, s->length);
> >> ps = s;
> >> }
> >> - if (dma_map_cont(sg, start, i, sg+out, pages, need) < 0)
> >> + if (dma_map_cont(start_sg, i - start, sg+out, pages, need) < 0)
> >> goto error;
> >> out++;
> >> flush_gart();
> >
> > Your patch is (very) buggy, the whole premise of doing chained sg
> > entries makes sg + int illegal!
> >
>
> You're right. I'll send a fix asap.
Did you see this one, I cooked it up after sending that mail out. Please
review :-)
diff --git a/arch/x86_64/kernel/pci-gart.c b/arch/x86_64/kernel/pci-gart.c
index 2e22a3a..b16384f 100644
--- a/arch/x86_64/kernel/pci-gart.c
+++ b/arch/x86_64/kernel/pci-gart.c
@@ -381,7 +381,7 @@ int gart_map_sg(struct device *dev, struct scatterlist *sg, int nents, int dir)
int start;
unsigned long pages = 0;
int need = 0, nextneed;
- struct scatterlist *s, *ps, *start_sg;
+ struct scatterlist *s, *ps, *start_sg, *sgmap;
if (nents == 0)
return 0;
@@ -391,7 +391,7 @@ int gart_map_sg(struct device *dev, struct scatterlist *sg, int nents, int dir)
out = 0;
start = 0;
- start_sg = sg;
+ start_sg = sgmap = sg;
ps = NULL; /* shut up gcc */
for_each_sg(sg, s, nents, i) {
dma_addr_t addr = page_to_phys(s->page) + s->offset;
@@ -405,11 +405,12 @@ int gart_map_sg(struct device *dev, struct scatterlist *sg, int nents, int dir)
/* Can only merge when the last chunk ends on a page
boundary and the new one doesn't have an offset. */
if (!iommu_merge || !nextneed || !need || s->offset ||
- (ps->offset + ps->length) % PAGE_SIZE) {
- if (dma_map_cont(start_sg, i - start, sg+out,
+ (ps->offset + ps->length) % PAGE_SIZE) {
+ if (dma_map_cont(start_sg, i - start, sgmap,
pages, need) < 0)
goto error;
out++;
+ sgmap = sg_next(sgmap);
pages = 0;
start = i;
start_sg = s;
@@ -420,7 +421,7 @@ int gart_map_sg(struct device *dev, struct scatterlist *sg, int nents, int dir)
pages += to_pages(s->offset, s->length);
ps = s;
}
- if (dma_map_cont(start_sg, i - start, sg+out, pages, need) < 0)
+ if (dma_map_cont(start_sg, i - start, sgmap, pages, need) < 0)
goto error;
out++;
flush_gart();
--
Jens Axboe
next prev parent reply other threads:[~2007-05-21 7:14 UTC|newest]
Thread overview: 24+ messages / expand[flat|nested] mbox.gz Atom feed top
2007-05-10 11:40 [PATCH 0/12] Chaining sg lists for bio IO commands v4 Jens Axboe
2007-05-10 11:40 ` [PATCH 1/12] crypto: don't pollute the global namespace with sg_next() Jens Axboe
2007-05-10 13:55 ` Benny Halevy
2007-05-10 21:37 ` Jens Axboe
2007-05-11 5:20 ` Benny Halevy
2007-05-12 2:34 ` Herbert Xu
2007-05-10 11:40 ` [PATCH 2/12] Add sg helpers for iterating over a scatterlist table Jens Axboe
2007-05-10 11:40 ` [PATCH 3/12] libata: convert to using sg helpers Jens Axboe
2007-05-10 11:40 ` [PATCH 4/12] block: " Jens Axboe
2007-05-10 11:40 ` [PATCH 5/12] scsi: " Jens Axboe
2007-05-10 11:40 ` [PATCH 6/12] i386 dma_map_sg: " Jens Axboe
2007-05-10 11:40 ` [PATCH 7/12] i386 sg: add support for chaining scatterlists Jens Axboe
2007-05-10 13:00 ` Satyam Sharma
2007-05-10 13:23 ` Satyam Sharma
2007-05-10 11:40 ` [PATCH 8/12] x86-64: update iommu/dma mapping functions to sg helpers Jens Axboe
2007-05-10 13:48 ` Benny Halevy
2007-05-10 21:38 ` Jens Axboe
2007-05-21 6:32 ` Jens Axboe
2007-05-21 7:09 ` Benny Halevy
2007-05-21 7:13 ` Jens Axboe [this message]
2007-05-10 11:40 ` [PATCH 9/12] x86-64: enable sg chaining Jens Axboe
2007-05-10 11:40 ` [PATCH 10/12] scsi: simplify scsi_free_sgtable() Jens Axboe
2007-05-10 11:40 ` [PATCH 11/12] SCSI: support for allocating large scatterlists Jens Axboe
2007-05-10 11:40 ` [PATCH 12/12] ll_rw_blk: temporarily enable max_segments tweaking Jens Axboe
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