Fix loop terminating conditions in fill_sg().

Signed-off-by: David S. Miller <davem@davemloft.net>
Signed-off-by: Jens Axboe <jens.axboe@oracle.com>
This commit is contained in:
David S. Miller 2007-10-17 04:08:48 -07:00 committed by Jens Axboe
parent 60573b874b
commit 5804509e65
2 changed files with 15 additions and 12 deletions

View file

@ -475,12 +475,11 @@ static void dma_4u_unmap_single(struct device *dev, dma_addr_t bus_addr,
#define SG_ENT_PHYS_ADDRESS(SG) \
(__pa(page_address((SG)->page)) + (SG)->offset)
static inline void fill_sg(iopte_t *iopte, struct scatterlist *sg,
int nused, int nelems,
unsigned long iopte_protection)
static void fill_sg(iopte_t *iopte, struct scatterlist *sg,
int nused, int nelems,
unsigned long iopte_protection)
{
struct scatterlist *dma_sg = sg;
struct scatterlist *sg_end = sg_last(sg, nelems);
int i;
for (i = 0; i < nused; i++) {
@ -516,6 +515,7 @@ static inline void fill_sg(iopte_t *iopte, struct scatterlist *sg,
break;
}
sg = sg_next(sg);
nelems--;
}
pteval = iopte_protection | (pteval & IOPTE_PAGE);
@ -529,18 +529,20 @@ static inline void fill_sg(iopte_t *iopte, struct scatterlist *sg,
pteval = (pteval & IOPTE_PAGE) + len;
sg = sg_next(sg);
nelems--;
/* Skip over any tail mappings we've fully mapped,
* adjusting pteval along the way. Stop when we
* detect a page crossing event.
*/
while (sg != sg_end &&
while (nelems &&
(pteval << (64 - IO_PAGE_SHIFT)) != 0UL &&
(pteval == SG_ENT_PHYS_ADDRESS(sg)) &&
((pteval ^
(SG_ENT_PHYS_ADDRESS(sg) + sg->length - 1UL)) >> IO_PAGE_SHIFT) == 0UL) {
pteval += sg->length;
sg = sg_next(sg);
nelems--;
}
if ((pteval << (64 - IO_PAGE_SHIFT)) == 0UL)
pteval = ~0UL;

View file

@ -368,12 +368,11 @@ static void dma_4v_unmap_single(struct device *dev, dma_addr_t bus_addr,
#define SG_ENT_PHYS_ADDRESS(SG) \
(__pa(page_address((SG)->page)) + (SG)->offset)
static inline long fill_sg(long entry, struct device *dev,
struct scatterlist *sg,
int nused, int nelems, unsigned long prot)
static long fill_sg(long entry, struct device *dev,
struct scatterlist *sg,
int nused, int nelems, unsigned long prot)
{
struct scatterlist *dma_sg = sg;
struct scatterlist *sg_end = sg_last(sg, nelems);
unsigned long flags;
int i;
@ -414,6 +413,7 @@ static inline long fill_sg(long entry, struct device *dev,
break;
}
sg = sg_next(sg);
nelems--;
}
pteval = (pteval & IOPTE_PAGE);
@ -432,19 +432,20 @@ static inline long fill_sg(long entry, struct device *dev,
pteval = (pteval & IOPTE_PAGE) + len;
sg = sg_next(sg);
nelems--;
/* Skip over any tail mappings we've fully mapped,
* adjusting pteval along the way. Stop when we
* detect a page crossing event.
*/
while ((pteval << (64 - IO_PAGE_SHIFT)) != 0UL &&
while (nelems &&
(pteval << (64 - IO_PAGE_SHIFT)) != 0UL &&
(pteval == SG_ENT_PHYS_ADDRESS(sg)) &&
((pteval ^
(SG_ENT_PHYS_ADDRESS(sg) + sg->length - 1UL)) >> IO_PAGE_SHIFT) == 0UL) {
pteval += sg->length;
if (sg == sg_end)
break;
sg = sg_next(sg);
nelems--;
}
if ((pteval << (64 - IO_PAGE_SHIFT)) == 0UL)
pteval = ~0UL;