[<prev] [next>] [<thread-prev] [thread-next>] [day] [month] [year] [list]
Date: Mon, 10 Oct 2011 21:52:05 +0900
From: KyongHo Cho <pullip.cho@...sung.com>
To: Ohad Ben-Cohen <ohad@...ery.com>
Cc: "Roedel, Joerg" <Joerg.Roedel@....com>,
"iommu@...ts.linux-foundation.org" <iommu@...ts.linux-foundation.org>,
"linux-omap@...r.kernel.org" <linux-omap@...r.kernel.org>,
Hiroshi DOYU <Hiroshi.DOYU@...ia.com>,
Laurent Pinchart <laurent.pinchart@...asonboard.com>,
David Woodhouse <dwmw2@...radead.org>,
"linux-arm-kernel@...ts.infradead.org"
<linux-arm-kernel@...ts.infradead.org>,
David Brown <davidb@...eaurora.org>,
Arnd Bergmann <arnd@...db.de>,
"linux-kernel@...r.kernel.org" <linux-kernel@...r.kernel.org>,
Stepan Moskovchenko <stepanm@...eaurora.org>,
"kvm@...r.kernel.org" <kvm@...r.kernel.org>
Subject: Re: [PATCH v3 1/6] iommu/core: split mapping to page sizes as
supported by the hardware
On Mon, Oct 3, 2011 at 12:58 AM, Ohad Ben-Cohen <ohad@...ery.com> wrote:
> int iommu_map(struct iommu_domain *domain, unsigned long iova,
> - phys_addr_t paddr, int gfp_order, int prot)
> + phys_addr_t paddr, size_t size, int prot)
> {
> - size_t size;
> + int ret = 0;
> +
> + /*
> + * both the virtual address and the physical one, as well as
> + * the size of the mapping, must be aligned (at least) to the
> + * size of the smallest page supported by the hardware
> + */
> + if (!IS_ALIGNED(iova | paddr | size, iommu_min_pagesz)) {
> + pr_err("unaligned: iova 0x%lx pa 0x%lx size 0x%lx min_pagesz "
> + "0x%x\n", iova, (unsigned long)paddr,
> + (unsigned long)size, iommu_min_pagesz);
> + return -EINVAL;
> + }
>
> - size = 0x1000UL << gfp_order;
> + pr_debug("map: iova 0x%lx pa 0x%lx size 0x%lx\n", iova,
> + (unsigned long)paddr, (unsigned long)size);
>
> - BUG_ON(!IS_ALIGNED(iova | paddr, size));
> + while (size) {
> + unsigned long pgsize, addr_merge = iova | paddr;
> + unsigned int pgsize_idx;
>
> - return iommu_ops->map(domain, iova, paddr, gfp_order, prot);
> + /* Max page size that still fits into 'size' */
> + pgsize_idx = __fls(size);
> +
> + /* need to consider alignment requirements ? */
> + if (likely(addr_merge)) {
> + /* Max page size allowed by both iova and paddr */
> + unsigned int align_pgsize_idx = __ffs(addr_merge);
> +
> + pgsize_idx = min(pgsize_idx, align_pgsize_idx);
> + }
> +
> + /* build a mask of acceptable page sizes */
> + pgsize = (1UL << (pgsize_idx + 1)) - 1;
> +
> + /* throw away page sizes not supported by the hardware */
> + pgsize &= iommu_pgsize_bitmap;
> +
> + /* pick the biggest page */
> + pgsize_idx = __fls(pgsize);
> + pgsize = 1UL << pgsize_idx;
> +
> + /* convert index to page order */
> + pgsize_idx -= PAGE_SHIFT;
> +
> + pr_debug("mapping: iova 0x%lx pa 0x%lx order %u\n", iova,
> + (unsigned long)paddr, pgsize_idx);
> +
> + ret = iommu_ops->map(domain, iova, paddr, pgsize_idx, prot);
> + if (ret)
> + break;
> +
> + iova += pgsize;
> + paddr += pgsize;
> + size -= pgsize;
> + }
> +
> + return ret;
> }
> EXPORT_SYMBOL_GPL(iommu_map);
Do not we need to unmap all intermediate mappings if iommu_map() is failed?
I think iommu_map() must map the entire given area if it successes.
Otherwise, it should map nothing.
I think it can be simply done with calling iommu_unmap()
with Joerg's previous suggestion about iommu_unmap().
Regards,
KyongHo.
--
To unsubscribe from this list: send the line "unsubscribe linux-kernel" in
the body of a message to majordomo@...r.kernel.org
More majordomo info at http://vger.kernel.org/majordomo-info.html
Please read the FAQ at http://www.tux.org/lkml/
Powered by blists - more mailing lists