| Message ID | 1306931102-10943-2-git-send-email-laurent.pinchart@ideasonboard.com (mailing list archive) |
|---|---|
| State | Superseded, archived |
| Delegated to: | Tony Lindgren |
| Headers | show |
* Laurent Pinchart <laurent.pinchart@ideasonboard.com> [110601 05:21]: > The IOMMU virtual memory mapping API requires page-aligned buffers. > There's no hardware reason behind such a restriction. Remove it by > rounding the address of the first page entry down, and adding the offset > back to the IOMMU virtual address. Does this one also fix some bug? Tony -- To unsubscribe from this list: send the line "unsubscribe linux-omap" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html
On Wednesday 01 June 2011 14:50:24 Tony Lindgren wrote: > * Laurent Pinchart <laurent.pinchart@ideasonboard.com> [110601 05:21]: > > The IOMMU virtual memory mapping API requires page-aligned buffers. > > There's no hardware reason behind such a restriction. Remove it by > > rounding the address of the first page entry down, and adding the offset > > back to the IOMMU virtual address. > > Does this one also fix some bug? Yes, but no oops. It fixes an OMAP3 ISP failure when the buffer passed from userspace is not page-aligned.
* Laurent Pinchart <laurent.pinchart@ideasonboard.com> [110601 06:04]: > On Wednesday 01 June 2011 14:50:24 Tony Lindgren wrote: > > * Laurent Pinchart <laurent.pinchart@ideasonboard.com> [110601 05:21]: > > > The IOMMU virtual memory mapping API requires page-aligned buffers. > > > There's no hardware reason behind such a restriction. Remove it by > > > rounding the address of the first page entry down, and adding the offset > > > back to the IOMMU virtual address. > > > > Does this one also fix some bug? > > Yes, but no oops. It fixes an OMAP3 ISP failure when the buffer passed from > userspace is not page-aligned. OK, thanks. I'll update the description with that and apply both to devel-fixes. Tony -- To unsubscribe from this list: send the line "unsubscribe linux-omap" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html
* Tony Lindgren <tony@atomide.com> [110601 06:07]: > * Laurent Pinchart <laurent.pinchart@ideasonboard.com> [110601 06:04]: > > On Wednesday 01 June 2011 14:50:24 Tony Lindgren wrote: > > > * Laurent Pinchart <laurent.pinchart@ideasonboard.com> [110601 05:21]: > > > > The IOMMU virtual memory mapping API requires page-aligned buffers. > > > > There's no hardware reason behind such a restriction. Remove it by > > > > rounding the address of the first page entry down, and adding the offset > > > > back to the IOMMU virtual address. > > > > > > Does this one also fix some bug? > > > > Yes, but no oops. It fixes an OMAP3 ISP failure when the buffer passed from > > userspace is not page-aligned. > > OK, thanks. I'll update the description with that and apply both to devel-fixes. Oops not quite. Please repost one more time with linux-arm-kernel also Cc'd for review. Otherwise I have to repost them before merging.. Thanks, Tony -- To unsubscribe from this list: send the line "unsubscribe linux-omap" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html
diff --git a/arch/arm/plat-omap/iovmm.c b/arch/arm/plat-omap/iovmm.c index b82cef4..fa5ae98 100644 --- a/arch/arm/plat-omap/iovmm.c +++ b/arch/arm/plat-omap/iovmm.c @@ -60,6 +60,15 @@ static struct kmem_cache *iovm_area_cachep; +/* return the offset of the first scatterlist entry in a sg table */ +static unsigned int sgtable_offset(const struct sg_table *sgt) +{ + if (!sgt || !sgt->nents) + return 0; + + return sgt->sgl->offset; +} + /* return total bytes of sg buffers */ static size_t sgtable_len(const struct sg_table *sgt) { @@ -72,11 +81,17 @@ static size_t sgtable_len(const struct sg_table *sgt) for_each_sg(sgt->sgl, sg, sgt->nents, i) { size_t bytes; - bytes = sg_dma_len(sg); + bytes = sg_dma_len(sg) + sg->offset; if (!iopgsz_ok(bytes)) { - pr_err("%s: sg[%d] not iommu pagesize(%x)\n", - __func__, i, bytes); + pr_err("%s: sg[%d] not iommu pagesize(%u %u)\n", + __func__, i, bytes, sg->offset); + return 0; + } + + if (i && sg->offset) { + pr_err("%s: sg[%d] offset not allowed in internal " + "entries\n", __func__, i); return 0; } @@ -207,8 +222,8 @@ static void *vmap_sg(const struct sg_table *sgt) u32 pa; int err; - pa = sg_phys(sg); - bytes = sg_dma_len(sg); + pa = sg_phys(sg) - sg->offset; + bytes = sg_dma_len(sg) + sg->offset; BUG_ON(bytes != PAGE_SIZE); @@ -485,8 +500,8 @@ static int map_iovm_area(struct iommu *obj, struct iovm_struct *new, size_t bytes; struct iotlb_entry e; - pa = sg_phys(sg); - bytes = sg_dma_len(sg); + pa = sg_phys(sg) - sg->offset; + bytes = sg_dma_len(sg) + sg->offset; flags &= ~IOVMF_PGSZ_MASK; pgsz = bytes_to_iopgsz(bytes); @@ -666,7 +681,7 @@ u32 iommu_vmap(struct iommu *obj, u32 da, const struct sg_table *sgt, if (IS_ERR_VALUE(da)) vunmap_sg(va); - return da; + return da + sgtable_offset(sgt); } EXPORT_SYMBOL_GPL(iommu_vmap); @@ -685,6 +700,7 @@ struct sg_table *iommu_vunmap(struct iommu *obj, u32 da) * 'sgt' is allocated before 'iommu_vmalloc()' is called. * Just returns 'sgt' to the caller to free */ + da &= PAGE_MASK; sgt = unmap_vm_area(obj, da, vunmap_sg, IOVMF_DISCONT | IOVMF_MMIO); if (!sgt) dev_dbg(obj->dev, "%s: No sgt\n", __func__);