diff options
Diffstat (limited to 'drivers/iommu/iommu.c')
-rw-r--r-- | drivers/iommu/iommu.c | 121 |
1 files changed, 108 insertions, 13 deletions
diff --git a/drivers/iommu/iommu.c b/drivers/iommu/iommu.c index 9c35be4..2198b2d 100644 --- a/drivers/iommu/iommu.c +++ b/drivers/iommu/iommu.c @@ -16,6 +16,8 @@ * Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA */ +#define pr_fmt(fmt) "%s: " fmt, __func__ + #include <linux/device.h> #include <linux/kernel.h> #include <linux/bug.h> @@ -141,7 +143,7 @@ struct iommu_domain *iommu_domain_alloc(struct bus_type *bus) if (bus == NULL || bus->iommu_ops == NULL) return NULL; - domain = kmalloc(sizeof(*domain), GFP_KERNEL); + domain = kzalloc(sizeof(*domain), GFP_KERNEL); if (!domain) return NULL; @@ -208,33 +210,126 @@ int iommu_domain_has_cap(struct iommu_domain *domain, EXPORT_SYMBOL_GPL(iommu_domain_has_cap); 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; + unsigned long orig_iova = iova; + unsigned int min_pagesz; + size_t orig_size = size; + int ret = 0; if (unlikely(domain->ops->map == NULL)) return -ENODEV; - size = PAGE_SIZE << gfp_order; + /* find out the minimum page size supported */ + min_pagesz = 1 << __ffs(domain->ops->pgsize_bitmap); + + /* + * 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, 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, min_pagesz); + return -EINVAL; + } + + pr_debug("map: iova 0x%lx pa 0x%lx size 0x%lx\n", iova, + (unsigned long)paddr, (unsigned long)size); + + while (size) { + unsigned long pgsize, addr_merge = iova | paddr; + unsigned int pgsize_idx; + + /* 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 &= domain->ops->pgsize_bitmap; - BUG_ON(!IS_ALIGNED(iova | paddr, size)); + /* make sure we're still sane */ + BUG_ON(!pgsize); - return domain->ops->map(domain, iova, paddr, gfp_order, prot); + /* pick the biggest page */ + pgsize_idx = __fls(pgsize); + pgsize = 1UL << pgsize_idx; + + pr_debug("mapping: iova 0x%lx pa 0x%lx pgsize %lu\n", iova, + (unsigned long)paddr, pgsize); + + ret = domain->ops->map(domain, iova, paddr, pgsize, prot); + if (ret) + break; + + iova += pgsize; + paddr += pgsize; + size -= pgsize; + } + + /* unroll mapping in case something went wrong */ + if (ret) + iommu_unmap(domain, orig_iova, orig_size - size); + + return ret; } EXPORT_SYMBOL_GPL(iommu_map); -int iommu_unmap(struct iommu_domain *domain, unsigned long iova, int gfp_order) +size_t iommu_unmap(struct iommu_domain *domain, unsigned long iova, size_t size) { - size_t size; + size_t unmapped_page, unmapped = 0; + unsigned int min_pagesz; if (unlikely(domain->ops->unmap == NULL)) return -ENODEV; - size = PAGE_SIZE << gfp_order; - - BUG_ON(!IS_ALIGNED(iova, size)); - - return domain->ops->unmap(domain, iova, gfp_order); + /* find out the minimum page size supported */ + min_pagesz = 1 << __ffs(domain->ops->pgsize_bitmap); + + /* + * The virtual address, 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 | size, min_pagesz)) { + pr_err("unaligned: iova 0x%lx size 0x%lx min_pagesz 0x%x\n", + iova, (unsigned long)size, min_pagesz); + return -EINVAL; + } + + pr_debug("unmap this: iova 0x%lx size 0x%lx\n", iova, + (unsigned long)size); + + /* + * Keep iterating until we either unmap 'size' bytes (or more) + * or we hit an area that isn't mapped. + */ + while (unmapped < size) { + size_t left = size - unmapped; + + unmapped_page = domain->ops->unmap(domain, iova, left); + if (!unmapped_page) + break; + + pr_debug("unmapped: iova 0x%lx size %lx\n", iova, + (unsigned long)unmapped_page); + + iova += unmapped_page; + unmapped += unmapped_page; + } + + return unmapped; } EXPORT_SYMBOL_GPL(iommu_unmap); |