Merge branch 'iommu/page-sizes' into x86/amd

Conflicts:
	drivers/iommu/amd_iommu.c

6 files changed, 181 insertions, 60 deletions

diff --git a/drivers/iommu/amd_iommu.c b/drivers/iommu/amd_iommu.c
index 2a46b1d7a601..a7cbcd46af9e 100644
--- a/drivers/iommu/amd_iommu.c
+++ b/drivers/iommu/amd_iommu.c
@@ -44,6 +44,24 @@
 
 #define LOOP_TIMEOUT    100000
 
+/*
+ * This bitmap is used to advertise the page sizes our hardware support
+ * to the IOMMU core, which will then use this information to split
+ * physically contiguous memory regions it is mapping into page sizes
+ * that we support.
+ *
+ * Traditionally the IOMMU core just handed us the mappings directly,
+ * after making sure the size is an order of a 4KiB page and that the
+ * mapping has natural alignment.
+ *
+ * To retain this behavior, we currently advertise that we support
+ * all page sizes that are an order of 4KiB.
+ *
+ * If at some point we'd like to utilize the IOMMU core's new behavior,
+ * we could change this to advertise the real page sizes we support.
+ */
+#define AMD_IOMMU_PGSIZES       (~0xFFFUL)
+
 static DEFINE_RWLOCK(amd_iommu_devtable_lock);
 
 /* A list of preallocated protection domains */
@@ -3093,9 +3111,8 @@ static int amd_iommu_attach_device(struct iommu_domain *dom,
 }
 
 static int amd_iommu_map(struct iommu_domain *dom, unsigned long iova,
-                         phys_addr_t paddr, int gfp_order, int iommu_prot)
+                         phys_addr_t paddr, size_t page_size, int iommu_prot)
 {
-        unsigned long page_size = 0x1000UL << gfp_order;
         struct protection_domain *domain = dom->priv;
         int prot = 0;
         int ret;
@@ -3115,24 +3132,22 @@ static int amd_iommu_map(struct iommu_domain *dom, unsigned long iova,
         return ret;
 }
 
-static int amd_iommu_unmap(struct iommu_domain *dom, unsigned long iova,
-                           int gfp_order)
+static size_t amd_iommu_unmap(struct iommu_domain *dom, unsigned long iova,
+                           size_t page_size)
 {
         struct protection_domain *domain = dom->priv;
-        unsigned long page_size, unmap_size;
+        size_t unmap_size;
 
         if (domain->mode == PAGE_MODE_NONE)
                 return -EINVAL;
 
-        page_size  = 0x1000UL << gfp_order;
-
         mutex_lock(&domain->api_lock);
         unmap_size = iommu_unmap_page(domain, iova, page_size);
         mutex_unlock(&domain->api_lock);
 
         domain_flush_tlb_pde(domain);
 
-        return get_order(unmap_size);
+        return unmap_size;
 }
 
 static phys_addr_t amd_iommu_iova_to_phys(struct iommu_domain *dom,
@@ -3182,6 +3197,7 @@ static struct iommu_ops amd_iommu_ops = {
         .unmap = amd_iommu_unmap,
         .iova_to_phys = amd_iommu_iova_to_phys,
         .domain_has_cap = amd_iommu_domain_has_cap,
+        .pgsize_bitmap  = AMD_IOMMU_PGSIZES,
 };
 
 /*****************************************************************************
diff --git a/drivers/iommu/intel-iommu.c b/drivers/iommu/intel-iommu.c
index a004c3945c67..c181883c2f9a 100644
--- a/drivers/iommu/intel-iommu.c
+++ b/drivers/iommu/intel-iommu.c
@@ -78,6 +78,24 @@
 #define LEVEL_STRIDE            (9)
 #define LEVEL_MASK              (((u64)1 << LEVEL_STRIDE) - 1)
 
+/*
+ * This bitmap is used to advertise the page sizes our hardware support
+ * to the IOMMU core, which will then use this information to split
+ * physically contiguous memory regions it is mapping into page sizes
+ * that we support.
+ *
+ * Traditionally the IOMMU core just handed us the mappings directly,
+ * after making sure the size is an order of a 4KiB page and that the
+ * mapping has natural alignment.
+ *
+ * To retain this behavior, we currently advertise that we support
+ * all page sizes that are an order of 4KiB.
+ *
+ * If at some point we'd like to utilize the IOMMU core's new behavior,
+ * we could change this to advertise the real page sizes we support.
+ */
+#define INTEL_IOMMU_PGSIZES     (~0xFFFUL)
+
 static inline int agaw_to_level(int agaw)
 {
         return agaw + 2;
@@ -3979,12 +3997,11 @@ static void intel_iommu_detach_device(struct iommu_domain *domain,
 
 static int intel_iommu_map(struct iommu_domain *domain,
                            unsigned long iova, phys_addr_t hpa,
-                           int gfp_order, int iommu_prot)
+                           size_t size, int iommu_prot)
 {
         struct dmar_domain *dmar_domain = domain->priv;
         u64 max_addr;
         int prot = 0;
-        size_t size;
         int ret;
 
         if (iommu_prot & IOMMU_READ)
@@ -3994,7 +4011,6 @@ static int intel_iommu_map(struct iommu_domain *domain,
         if ((iommu_prot & IOMMU_CACHE) && dmar_domain->iommu_snooping)
                 prot |= DMA_PTE_SNP;
 
-        size     = PAGE_SIZE << gfp_order;
         max_addr = iova + size;
         if (dmar_domain->max_addr < max_addr) {
                 u64 end;
@@ -4017,11 +4033,10 @@ static int intel_iommu_map(struct iommu_domain *domain,
         return ret;
 }
 
-static int intel_iommu_unmap(struct iommu_domain *domain,
-                             unsigned long iova, int gfp_order)
+static size_t intel_iommu_unmap(struct iommu_domain *domain,
+                             unsigned long iova, size_t size)
 {
         struct dmar_domain *dmar_domain = domain->priv;
-        size_t size = PAGE_SIZE << gfp_order;
         int order;
 
         order = dma_pte_clear_range(dmar_domain, iova >> VTD_PAGE_SHIFT,
@@ -4030,7 +4045,7 @@ static int intel_iommu_unmap(struct iommu_domain *domain,
         if (dmar_domain->max_addr == iova + size)
                 dmar_domain->max_addr = iova;
 
-        return order;
+        return PAGE_SIZE << order;
 }
 
 static phys_addr_t intel_iommu_iova_to_phys(struct iommu_domain *domain,
@@ -4069,6 +4084,7 @@ static struct iommu_ops intel_iommu_ops = {
         .unmap          = intel_iommu_unmap,
         .iova_to_phys   = intel_iommu_iova_to_phys,
         .domain_has_cap = intel_iommu_domain_has_cap,
+        .pgsize_bitmap  = INTEL_IOMMU_PGSIZES,
 };
 
 static void __devinit quirk_iommu_rwbf(struct pci_dev *dev)
diff --git a/drivers/iommu/iommu.c b/drivers/iommu/iommu.c
index 2fb2963df553..84cdd8ac81f1 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>
@@ -157,32 +159,125 @@ 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);
diff --git a/drivers/iommu/msm_iommu.c b/drivers/iommu/msm_iommu.c
index 5865dd2e28f9..08a90b88e40d 100644
--- a/drivers/iommu/msm_iommu.c
+++ b/drivers/iommu/msm_iommu.c
@@ -42,6 +42,9 @@ __asm__ __volatile__ (							\
 #define RCP15_PRRR(reg)         MRC(reg, p15, 0, c10, c2, 0)
 #define RCP15_NMRR(reg)         MRC(reg, p15, 0, c10, c2, 1)
 
+/* bitmap of the page sizes currently supported */
+#define MSM_IOMMU_PGSIZES       (SZ_4K | SZ_64K | SZ_1M | SZ_16M)
+
 static int msm_iommu_tex_class[4];
 
 DEFINE_SPINLOCK(msm_iommu_lock);
@@ -352,7 +355,7 @@ fail:
 }
 
 static int msm_iommu_map(struct iommu_domain *domain, unsigned long va,
-                         phys_addr_t pa, int order, int prot)
+                         phys_addr_t pa, size_t len, int prot)
 {
         struct msm_priv *priv;
         unsigned long flags;
@@ -363,7 +366,6 @@ static int msm_iommu_map(struct iommu_domain *domain, unsigned long va,
         unsigned long *sl_pte;
         unsigned long sl_offset;
         unsigned int pgprot;
-        size_t len = 0x1000UL << order;
         int ret = 0, tex, sh;
 
         spin_lock_irqsave(&msm_iommu_lock, flags);
@@ -463,8 +465,8 @@ fail:
         return ret;
 }
 
-static int msm_iommu_unmap(struct iommu_domain *domain, unsigned long va,
-                            int order)
+static size_t msm_iommu_unmap(struct iommu_domain *domain, unsigned long va,
+                            size_t len)
 {
         struct msm_priv *priv;
         unsigned long flags;
@@ -474,7 +476,6 @@ static int msm_iommu_unmap(struct iommu_domain *domain, unsigned long va,
         unsigned long *sl_table;
         unsigned long *sl_pte;
         unsigned long sl_offset;
-        size_t len = 0x1000UL << order;
         int i, ret = 0;
 
         spin_lock_irqsave(&msm_iommu_lock, flags);
@@ -544,15 +545,12 @@ static int msm_iommu_unmap(struct iommu_domain *domain, unsigned long va,
 
         ret = __flush_iotlb(domain);
 
-        /*
-         * the IOMMU API requires us to return the order of the unmapped
-         * page (on success).
-         */
-        if (!ret)
-                ret = order;
 fail:
         spin_unlock_irqrestore(&msm_iommu_lock, flags);
-        return ret;
+
+        /* the IOMMU API requires us to return how many bytes were unmapped */
+        len = ret ? 0 : len;
+        return len;
 }
 
 static phys_addr_t msm_iommu_iova_to_phys(struct iommu_domain *domain,
@@ -684,7 +682,8 @@ static struct iommu_ops msm_iommu_ops = {
         .map = msm_iommu_map,
         .unmap = msm_iommu_unmap,
         .iova_to_phys = msm_iommu_iova_to_phys,
-        .domain_has_cap = msm_iommu_domain_has_cap
+        .domain_has_cap = msm_iommu_domain_has_cap,
+        .pgsize_bitmap = MSM_IOMMU_PGSIZES,
 };
 
 static int __init get_tex_class(int icp, int ocp, int mt, int nos)
diff --git a/drivers/iommu/omap-iommu.c b/drivers/iommu/omap-iommu.c
index 8f32b2bf7587..08cf7ec5b4a5 100644
--- a/drivers/iommu/omap-iommu.c
+++ b/drivers/iommu/omap-iommu.c
@@ -33,6 +33,9 @@
              (__i < (n)) && (cr = __iotlb_read_cr((obj), __i), true);   \
              __i++)
 
+/* bitmap of the page sizes currently supported */
+#define OMAP_IOMMU_PGSIZES      (SZ_4K | SZ_64K | SZ_1M | SZ_16M)
+
 /**
  * struct omap_iommu_domain - omap iommu domain
  * @pgtable:    the page table
@@ -1019,12 +1022,11 @@ static void iopte_cachep_ctor(void *iopte)
 }
 
 static int omap_iommu_map(struct iommu_domain *domain, unsigned long da,
-                         phys_addr_t pa, int order, int prot)
+                         phys_addr_t pa, size_t bytes, int prot)
 {
         struct omap_iommu_domain *omap_domain = domain->priv;
         struct omap_iommu *oiommu = omap_domain->iommu_dev;
         struct device *dev = oiommu->dev;
-        size_t bytes = PAGE_SIZE << order;
         struct iotlb_entry e;
         int omap_pgsz;
         u32 ret, flags;
@@ -1049,19 +1051,16 @@ static int omap_iommu_map(struct iommu_domain *domain, unsigned long da,
         return ret;
 }
 
-static int omap_iommu_unmap(struct iommu_domain *domain, unsigned long da,
-                            int order)
+static size_t omap_iommu_unmap(struct iommu_domain *domain, unsigned long da,
+                            size_t size)
 {
         struct omap_iommu_domain *omap_domain = domain->priv;
         struct omap_iommu *oiommu = omap_domain->iommu_dev;
         struct device *dev = oiommu->dev;
-        size_t unmap_size;
-
-        dev_dbg(dev, "unmapping da 0x%lx order %d\n", da, order);
 
-        unmap_size = iopgtable_clear_entry(oiommu, da);
+        dev_dbg(dev, "unmapping da 0x%lx size %u\n", da, size);
 
-        return unmap_size ? get_order(unmap_size) : -EINVAL;
+        return iopgtable_clear_entry(oiommu, da);
 }
 
 static int
@@ -1211,6 +1210,7 @@ static struct iommu_ops omap_iommu_ops = {
         .unmap          = omap_iommu_unmap,
         .iova_to_phys   = omap_iommu_iova_to_phys,
         .domain_has_cap = omap_iommu_domain_has_cap,
+        .pgsize_bitmap  = OMAP_IOMMU_PGSIZES,
 };
 
 static int __init omap_iommu_init(void)
diff --git a/drivers/iommu/omap-iovmm.c b/drivers/iommu/omap-iovmm.c
index 46be456fcc00..6edc4ceba197 100644
--- a/drivers/iommu/omap-iovmm.c
+++ b/drivers/iommu/omap-iovmm.c
@@ -410,7 +410,6 @@ static int map_iovm_area(struct iommu_domain *domain, struct iovm_struct *new,
         unsigned int i, j;
         struct scatterlist *sg;
         u32 da = new->da_start;
-        int order;
 
         if (!domain || !sgt)
                 return -EINVAL;
@@ -429,12 +428,10 @@ static int map_iovm_area(struct iommu_domain *domain, struct iovm_struct *new,
                 if (bytes_to_iopgsz(bytes) < 0)
                         goto err_out;
 
-                order = get_order(bytes);
-
                 pr_debug("%s: [%d] %08x %08x(%x)\n", __func__,
                          i, da, pa, bytes);
 
-                err = iommu_map(domain, da, pa, order, flags);
+                err = iommu_map(domain, da, pa, bytes, flags);
                 if (err)
                         goto err_out;
 
@@ -449,10 +446,9 @@ err_out:
                 size_t bytes;
 
                 bytes = sg->length + sg->offset;
-                order = get_order(bytes);
 
                 /* ignore failures.. we're already handling one */
-                iommu_unmap(domain, da, order);
+                iommu_unmap(domain, da, bytes);
 
                 da += bytes;
         }
@@ -467,7 +463,8 @@ static void unmap_iovm_area(struct iommu_domain *domain, struct omap_iommu *obj,
         size_t total = area->da_end - area->da_start;
         const struct sg_table *sgt = area->sgt;
         struct scatterlist *sg;
-        int i, err;
+        int i;
+        size_t unmapped;
 
         BUG_ON(!sgtable_ok(sgt));
         BUG_ON((!total) || !IS_ALIGNED(total, PAGE_SIZE));
@@ -475,13 +472,11 @@ static void unmap_iovm_area(struct iommu_domain *domain, struct omap_iommu *obj,
         start = area->da_start;
         for_each_sg(sgt->sgl, sg, sgt->nents, i) {
                 size_t bytes;
-                int order;
 
                 bytes = sg->length + sg->offset;
-                order = get_order(bytes);
 
-                err = iommu_unmap(domain, start, order);
-                if (err < 0)
+                unmapped = iommu_unmap(domain, start, bytes);
+                if (unmapped < bytes)
                         break;
 
                 dev_dbg(obj->dev, "%s: unmap %08x(%x) %08x\n",