/* * Copyright (C) 2007-2008 Advanced Micro Devices, Inc. * Author: Joerg Roedel * Leo Duran * * This program is free software; you can redistribute it and/or modify it * under the terms of the GNU General Public License version 2 as published * by the Free Software Foundation. * * This program is distributed in the hope that it will be useful, * but WITHOUT ANY WARRANTY; without even the implied warranty of * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the * GNU General Public License for more details. * * You should have received a copy of the GNU General Public License * along with this program; if not, write to the Free Software * Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA */ #include #include #include #include #include #include #include #include #include #define CMD_SET_TYPE(cmd, t) ((cmd)->data[1] |= ((t) << 28)) #define to_pages(addr, size) \ (round_up(((addr) & ~PAGE_MASK) + (size), PAGE_SIZE) >> PAGE_SHIFT) #define EXIT_LOOP_COUNT 10000000 static DEFINE_RWLOCK(amd_iommu_devtable_lock); /* * general struct to manage commands send to an IOMMU */ struct command { u32 data[4]; }; static int dma_ops_unity_map(struct dma_ops_domain *dma_dom, struct unity_map_entry *e); /* returns !0 if the IOMMU is caching non-present entries in its TLB */ static int iommu_has_npcache(struct amd_iommu *iommu) { return iommu->cap & IOMMU_CAP_NPCACHE; } /**************************************************************************** * * IOMMU command queuing functions * ****************************************************************************/ /* * Writes the command to the IOMMUs command buffer and informs the * hardware about the new command. Must be called with iommu->lock held. */ static int __iommu_queue_command(struct amd_iommu *iommu, struct command *cmd) { u32 tail, head; u8 *target; tail = readl(iommu->mmio_base + MMIO_CMD_TAIL_OFFSET); target = (iommu->cmd_buf + tail); memcpy_toio(target, cmd, sizeof(*cmd)); tail = (tail + sizeof(*cmd)) % iommu->cmd_buf_size; head = readl(iommu->mmio_base + MMIO_CMD_HEAD_OFFSET); if (tail == head) return -ENOMEM; writel(tail, iommu->mmio_base + MMIO_CMD_TAIL_OFFSET); return 0; } /* * General queuing function for commands. Takes iommu->lock and calls * __iommu_queue_command(). */ static int iommu_queue_command(struct amd_iommu *iommu, struct command *cmd) { unsigned long flags; int ret; spin_lock_irqsave(&iommu->lock, flags); ret = __iommu_queue_command(iommu, cmd); spin_unlock_irqrestore(&iommu->lock, flags); return ret; } /* * This function is called whenever we need to ensure that the IOMMU has * completed execution of all commands we sent. It sends a * COMPLETION_WAIT command and waits for it to finish. The IOMMU informs * us about that by writing a value to a physical address we pass with * the command. */ static int iommu_completion_wait(struct amd_iommu *iommu) { int ret; struct command cmd; volatile u64 ready = 0; unsigned long ready_phys = virt_to_phys(&ready); unsigned long i = 0; memset(&cmd, 0, sizeof(cmd)); cmd.data[0] = LOW_U32(ready_phys) | CMD_COMPL_WAIT_STORE_MASK; cmd.data[1] = upper_32_bits(ready_phys); cmd.data[2] = 1; /* value written to 'ready' */ CMD_SET_TYPE(&cmd, CMD_COMPL_WAIT); iommu->need_sync = 0; ret = iommu_queue_command(iommu, &cmd); if (ret) return ret; while (!ready && (i < EXIT_LOOP_COUNT)) { ++i; cpu_relax(); } if (unlikely((i == EXIT_LOOP_COUNT) && printk_ratelimit())) printk(KERN_WARNING "AMD IOMMU: Completion wait loop failed\n"); return 0; } /* * Command send function for invalidating a device table entry */ static int iommu_queue_inv_dev_entry(struct amd_iommu *iommu, u16 devid) { struct command cmd; BUG_ON(iommu == NULL); memset(&cmd, 0, sizeof(cmd)); CMD_SET_TYPE(&cmd, CMD_INV_DEV_ENTRY); cmd.data[0] = devid; iommu->need_sync = 1; return iommu_queue_command(iommu, &cmd); } /* * Generic command send function for invalidaing TLB entries */ static int iommu_queue_inv_iommu_pages(struct amd_iommu *iommu, u64 address, u16 domid, int pde, int s) { struct command cmd; memset(&cmd, 0, sizeof(cmd)); address &= PAGE_MASK; CMD_SET_TYPE(&cmd, CMD_INV_IOMMU_PAGES); cmd.data[1] |= domid; cmd.data[2] = LOW_U32(address); cmd.data[3] = upper_32_bits(address); if (s) /* size bit - we flush more than one 4kb page */ cmd.data[2] |= CMD_INV_IOMMU_PAGES_SIZE_MASK; if (pde) /* PDE bit - we wan't flush everything not only the PTEs */ cmd.data[2] |= CMD_INV_IOMMU_PAGES_PDE_MASK; iommu->need_sync = 1; return iommu_queue_command(iommu, &cmd); } /* * TLB invalidation function which is called from the mapping functions. * It invalidates a single PTE if the range to flush is within a single * page. Otherwise it flushes the whole TLB of the IOMMU. */ static int iommu_flush_pages(struct amd_iommu *iommu, u16 domid, u64 address, size_t size) { int s = 0; unsigned pages = to_pages(address, size); address &= PAGE_MASK; if (pages > 1) { /* * If we have to flush more than one page, flush all * TLB entries for this domain */ address = CMD_INV_IOMMU_ALL_PAGES_ADDRESS; s = 1; } iommu_queue_inv_iommu_pages(iommu, address, domid, 0, s); return 0; } /**************************************************************************** * * The functions below are used the create the page table mappings for * unity mapped regions. * ****************************************************************************/ /* * Generic mapping functions. It maps a physical address into a DMA * address space. It allocates the page table pages if necessary. * In the future it can be extended to a generic mapping function * supporting all features of AMD IOMMU page tables like level skipping * and full 64 bit address spaces. */ static int iommu_map(struct protection_domain *dom, unsigned long bus_addr, unsigned long phys_addr, int prot) { u64 __pte, *pte, *page; bus_addr = PAGE_ALIGN(bus_addr); phys_addr = PAGE_ALIGN(bus_addr); /* only support 512GB address spaces for now */ if (bus_addr > IOMMU_MAP_SIZE_L3 || !(prot & IOMMU_PROT_MASK)) return -EINVAL; pte = &dom->pt_root[IOMMU_PTE_L2_INDEX(bus_addr)]; if (!IOMMU_PTE_PRESENT(*pte)) { page = (u64 *)get_zeroed_page(GFP_KERNEL); if (!page) return -ENOMEM; *pte = IOMMU_L2_PDE(virt_to_phys(page)); } pte = IOMMU_PTE_PAGE(*pte); pte = &pte[IOMMU_PTE_L1_INDEX(bus_addr)]; if (!IOMMU_PTE_PRESENT(*pte)) { page = (u64 *)get_zeroed_page(GFP_KERNEL); if (!page) return -ENOMEM; *pte = IOMMU_L1_PDE(virt_to_phys(page)); } pte = IOMMU_PTE_PAGE(*pte); pte = &pte[IOMMU_PTE_L0_INDEX(bus_addr)]; if (IOMMU_PTE_PRESENT(*pte)) return -EBUSY; __pte = phys_addr | IOMMU_PTE_P; if (prot & IOMMU_PROT_IR) __pte |= IOMMU_PTE_IR; if (prot & IOMMU_PROT_IW) __pte |= IOMMU_PTE_IW; *pte = __pte; return 0; } /* * This function checks if a specific unity mapping entry is needed for * this specific IOMMU. */ static int iommu_for_unity_map(struct amd_iommu *iommu, struct unity_map_entry *entry) { u16 bdf, i; for (i = entry->devid_start; i <= entry->devid_end; ++i) { bdf = amd_iommu_alias_table[i]; if (amd_iommu_rlookup_table[bdf] == iommu) return 1; } return 0; } /* * Init the unity mappings for a specific IOMMU in the system * * Basically iterates over all unity mapping entries and applies them to * the default domain DMA of that IOMMU if necessary. */ static int iommu_init_unity_mappings(struct amd_iommu *iommu) { struct unity_map_entry *entry; int ret; list_for_each_entry(entry, &amd_iommu_unity_map, list) { if (!iommu_for_unity_map(iommu, entry)) continue; ret = dma_ops_unity_map(iommu->default_dom, entry); if (ret) return ret; } return 0; } /* * This function actually applies the mapping to the page table of the * dma_ops domain. */ static int dma_ops_unity_map(struct dma_ops_domain *dma_dom, struct unity_map_entry *e) { u64 addr; int ret; for (addr = e->address_start; addr < e->address_end; addr += PAGE_SIZE) { ret = iommu_map(&dma_dom->domain, addr, addr, e->prot); if (ret) return ret; /* * if unity mapping is in aperture range mark the page * as allocated in the aperture */ if (addr < dma_dom->aperture_size) __set_bit(addr >> PAGE_SHIFT, dma_dom->bitmap); } return 0; } /* * Inits the unity mappings required for a specific device */ static int init_unity_mappings_for_device(struct dma_ops_domain *dma_dom, u16 devid) { struct unity_map_entry *e; int ret; list_for_each_entry(e, &amd_iommu_unity_map, list) { if (!(devid >= e->devid_start && devid <= e->devid_end)) continue; ret = dma_ops_unity_map(dma_dom, e); if (ret) return ret; } return 0; } /**************************************************************************** * * The next functions belong to the address allocator for the dma_ops * interface functions. They work like the allocators in the other IOMMU * drivers. Its basically a bitmap which marks the allocated pages in * the aperture. Maybe it could be enhanced in the future to a more * efficient allocator. * ****************************************************************************/ static unsigned long dma_mask_to_pages(unsigned long mask) { return (mask >> PAGE_SHIFT) + (PAGE_ALIGN(mask & ~PAGE_MASK) >> PAGE_SHIFT); } /* * The address allocator core function. * * called with domain->lock held */ static unsigned long dma_ops_alloc_addresses(struct device *dev, struct dma_ops_domain *dom, unsigned int pages) { unsigned long limit = dma_mask_to_pages(*dev->dma_mask); unsigned long address; unsigned long size = dom->aperture_size >> PAGE_SHIFT; unsigned long boundary_size; boundary_size = ALIGN(dma_get_seg_boundary(dev) + 1, PAGE_SIZE) >> PAGE_SHIFT; limit = limit < size ? limit : size; if (dom->next_bit >= limit) dom->next_bit = 0; address = iommu_area_alloc(dom->bitmap, limit, dom->next_bit, pages, 0 , boundary_size, 0); if (address == -1) address = iommu_area_alloc(dom->bitmap, limit, 0, pages, 0, boundary_size, 0); if (likely(address != -1)) { dom->next_bit = address + pages; address <<= PAGE_SHIFT; } else address = bad_dma_address; WARN_ON((address + (PAGE_SIZE*pages)) > dom->aperture_size); return address; } /* * The address free function. * * called with domain->lock held */ static void dma_ops_free_addresses(struct dma_ops_domain *dom, unsigned long address, unsigned int pages) { address >>= PAGE_SHIFT; iommu_area_free(dom->bitmap, address, pages); } /**************************************************************************** * * The next functions belong to the domain allocation. A domain is * allocated for every IOMMU as the default domain. If device isolation * is enabled, every device get its own domain. The most important thing * about domains is the page table mapping the DMA address space they * contain. * ****************************************************************************/ static u16 domain_id_alloc(void) { unsigned long flags; int id; write_lock_irqsave(&amd_iommu_devtable_lock, flags); id = find_first_zero_bit(amd_iommu_pd_alloc_bitmap, MAX_DOMAIN_ID); BUG_ON(id == 0); if (id > 0 && id < MAX_DOMAIN_ID) __set_bit(id, amd_iommu_pd_alloc_bitmap); else id = 0; write_unlock_irqrestore(&amd_iommu_devtable_lock, flags); return id; } /* * Used to reserve address ranges in the aperture (e.g. for exclusion * ranges. */ static void dma_ops_reserve_addresses(struct dma_ops_domain *dom, unsigned long start_page, unsigned int pages) { unsigned int last_page = dom->aperture_size >> PAGE_SHIFT; if (start_page + pages > last_page) pages = last_page - start_page; set_bit_string(dom->bitmap, start_page, pages); } static void dma_ops_free_pagetable(struct dma_ops_domain *dma_dom) { int i, j; u64 *p1, *p2, *p3; p1 = dma_dom->domain.pt_root; if (!p1) return; for (i = 0; i < 512; ++i) { if (!IOMMU_PTE_PRESENT(p1[i])) continue; p2 = IOMMU_PTE_PAGE(p1[i]); for (j = 0; j < 512; ++i) { if (!IOMMU_PTE_PRESENT(p2[j])) continue; p3 = IOMMU_PTE_PAGE(p2[j]); free_page((unsigned long)p3); } free_page((unsigned long)p2); } free_page((unsigned long)p1); } /* * Free a domain, only used if something went wrong in the * allocation path and we need to free an already allocated page table */ static void dma_ops_domain_free(struct dma_ops_domain *dom) { if (!dom) return; dma_ops_free_pagetable(dom); kfree(dom->pte_pages); kfree(dom->bitmap); kfree(dom); } /* * Allocates a new protection domain usable for the dma_ops functions. * It also intializes the page table and the address allocator data * structures required for the dma_ops interface */ static struct dma_ops_domain *dma_ops_domain_alloc(struct amd_iommu *iommu, unsigned order) { struct dma_ops_domain *dma_dom; unsigned i, num_pte_pages; u64 *l2_pde; u64 address; /* * Currently the DMA aperture must be between 32 MB and 1GB in size */ if ((order < 25) || (order > 30)) return NULL; dma_dom = kzalloc(sizeof(struct dma_ops_domain), GFP_KERNEL); if (!dma_dom) return NULL; spin_lock_init(&dma_dom->domain.lock); dma_dom->domain.id = domain_id_alloc(); if (dma_dom->domain.id == 0) goto free_dma_dom; dma_dom->domain.mode = PAGE_MODE_3_LEVEL; dma_dom->domain.pt_root = (void *)get_zeroed_page(GFP_KERNEL); dma_dom->domain.priv = dma_dom; if (!dma_dom->domain.pt_root) goto free_dma_dom; dma_dom->aperture_size = (1ULL << order); dma_dom->bitmap = kzalloc(dma_dom->aperture_size / (PAGE_SIZE * 8), GFP_KERNEL); if (!dma_dom->bitmap) goto free_dma_dom; /* * mark the first page as allocated so we never return 0 as * a valid dma-address. So we can use 0 as error value */ dma_dom->bitmap[0] = 1; dma_dom->next_bit = 0; /* Intialize the exclusion range if necessary */ if (iommu->exclusion_start && iommu->exclusion_start < dma_dom->aperture_size) { unsigned long startpage = iommu->exclusion_start >> PAGE_SHIFT; int pages = to_pages(iommu->exclusion_start, iommu->exclusion_length); dma_ops_reserve_addresses(dma_dom, startpage, pages); } /* * At the last step, build the page tables so we don't need to * allocate page table pages in the dma_ops mapping/unmapping * path. */ num_pte_pages = dma_dom->aperture_size / (PAGE_SIZE * 512); dma_dom->pte_pages = kzalloc(num_pte_pages * sizeof(void *), GFP_KERNEL); if (!dma_dom->pte_pages) goto free_dma_dom; l2_pde = (u64 *)get_zeroed_page(GFP_KERNEL); if (l2_pde == NULL) goto free_dma_dom; dma_dom->domain.pt_root[0] = IOMMU_L2_PDE(virt_to_phys(l2_pde)); for (i = 0; i < num_pte_pages; ++i) { dma_dom->pte_pages[i] = (u64 *)get_zeroed_page(GFP_KERNEL); if (!dma_dom->pte_pages[i]) goto free_dma_dom; address = virt_to_phys(dma_dom->pte_pages[i]); l2_pde[i] = IOMMU_L1_PDE(address); } return dma_dom; free_dma_dom: dma_ops_domain_free(dma_dom); return NULL; } /* * Find out the protection domain structure for a given PCI device. This * will give us the pointer to the page table root for example. */ static struct protection_domain *domain_for_device(u16 devid) { struct protection_domain *dom; unsigned long flags; read_lock_irqsave(&amd_iommu_devtable_lock, flags); dom = amd_iommu_pd_table[devid]; read_unlock_irqrestore(&amd_iommu_devtable_lock, flags); return dom; } /* * If a device is not yet associated with a domain, this function does * assigns it visible for the hardware */ static void set_device_domain(struct amd_iommu *iommu, struct protection_domain *domain, u16 devid) { unsigned long flags; u64 pte_root = virt_to_phys(domain->pt_root); pte_root |= (domain->mode & 0x07) << 9; pte_root |= IOMMU_PTE_IR | IOMMU_PTE_IW | IOMMU_PTE_P | 2; write_lock_irqsave(&amd_iommu_devtable_lock, flags); amd_iommu_dev_table[devid].data[0] = pte_root; amd_iommu_dev_table[devid].data[1] = pte_root >> 32; amd_iommu_dev_table[devid].data[2] = domain->id; amd_iommu_pd_table[devid] = domain; write_unlock_irqrestore(&amd_iommu_devtable_lock, flags); iommu_queue_inv_dev_entry(iommu, devid); iommu->need_sync = 1; } /***************************************************************************** * * The next functions belong to the dma_ops mapping/unmapping code. * *****************************************************************************/ /* * In the dma_ops path we only have the struct device. This function * finds the corresponding IOMMU, the protection domain and the * requestor id for a given device. * If the device is not yet associated with a domain this is also done * in this function. */ static int get_device_resources(struct device *dev, struct amd_iommu **iommu, struct protection_domain **domain, u16 *bdf) { struct dma_ops_domain *dma_dom; struct pci_dev *pcidev; u16 _bdf; BUG_ON(!dev || dev->bus != &pci_bus_type || !dev->dma_mask); pcidev = to_pci_dev(dev); _bdf = (pcidev->bus->number << 8) | pcidev->devfn; /* device not translated by any IOMMU in the system? */ if (_bdf >= amd_iommu_last_bdf) { *iommu = NULL; *domain = NULL; *bdf = 0xffff; return 0; } *bdf = amd_iommu_alias_table[_bdf]; *iommu = amd_iommu_rlookup_table[*bdf]; if (*iommu == NULL) return 0; dma_dom = (*iommu)->default_dom; *domain = domain_for_device(*bdf); if (*domain == NULL) { *domain = &dma_dom->domain; set_device_domain(*iommu, *domain, *bdf); printk(KERN_INFO "AMD IOMMU: Using protection domain %d for " "device ", (*domain)->id); print_devid(_bdf, 1); } return 1; } /* * This is the generic map function. It maps one 4kb page at paddr to * the given address in the DMA address space for the domain. */ static dma_addr_t dma_ops_domain_map(struct amd_iommu *iommu, struct dma_ops_domain *dom, unsigned long address, phys_addr_t paddr, int direction) { u64 *pte, __pte; WARN_ON(address > dom->aperture_size); paddr &= PAGE_MASK; pte = dom->pte_pages[IOMMU_PTE_L1_INDEX(address)]; pte += IOMMU_PTE_L0_INDEX(address); __pte = paddr | IOMMU_PTE_P | IOMMU_PTE_FC; if (direction == DMA_TO_DEVICE) __pte |= IOMMU_PTE_IR; else if (direction == DMA_FROM_DEVICE) __pte |= IOMMU_PTE_IW; else if (direction == DMA_BIDIRECTIONAL) __pte |= IOMMU_PTE_IR | IOMMU_PTE_IW; WARN_ON(*pte); *pte = __pte; return (dma_addr_t)address; } /* * The generic unmapping function for on page in the DMA address space. */ static void dma_ops_domain_unmap(struct amd_iommu *iommu, struct dma_ops_domain *dom, unsigned long address) { u64 *pte; if (address >= dom->aperture_size) return; WARN_ON(address & 0xfffULL || address > dom->aperture_size); pte = dom->pte_pages[IOMMU_PTE_L1_INDEX(address)]; pte += IOMMU_PTE_L0_INDEX(address); WARN_ON(!*pte); *pte = 0ULL; } /* * This function contains common code for mapping of a physically * contiguous memory region into DMA address space. It is uses by all * mapping functions provided by this IOMMU driver. * Must be called with the domain lock held. */ static dma_addr_t __map_single(struct device *dev, struct amd_iommu *iommu, struct dma_ops_domain *dma_dom, phys_addr_t paddr, size_t size, int dir) { dma_addr_t offset = paddr & ~PAGE_MASK; dma_addr_t address, start; unsigned int pages; int i; pages = to_pages(paddr, size); paddr &= PAGE_MASK; address = dma_ops_alloc_addresses(dev, dma_dom, pages); if (unlikely(address == bad_dma_address)) goto out; start = address; for (i = 0; i < pages; ++i) { dma_ops_domain_map(iommu, dma_dom, start, paddr, dir); paddr += PAGE_SIZE; start += PAGE_SIZE; } address += offset; out: return address; } /* * Does the reverse of the __map_single function. Must be called with * the domain lock held too */ static void __unmap_single(struct amd_iommu *iommu, struct dma_ops_domain *dma_dom, dma_addr_t dma_addr, size_t size, int dir) { dma_addr_t i, start; unsigned int pages; if ((dma_addr == 0) || (dma_addr + size > dma_dom->aperture_size)) return; pages = to_pages(dma_addr, size); dma_addr &= PAGE_MASK; start = dma_addr; for (i = 0; i < pages; ++i) { dma_ops_domain_unmap(iommu, dma_dom, start); start += PAGE_SIZE; } dma_ops_free_addresses(dma_dom, dma_addr, pages); } /* * The exported map_single function for dma_ops. */ static dma_addr_t map_single(struct device *dev, phys_addr_t paddr, size_t size, int dir) { unsigned long flags; struct amd_iommu *iommu; struct protection_domain *domain; u16 devid; dma_addr_t addr; get_device_resources(dev, &iommu, &domain, &devid); if (iommu == NULL || domain == NULL) /* device not handled by any AMD IOMMU */ return (dma_addr_t)paddr; spin_lock_irqsave(&domain->lock, flags); addr = __map_single(dev, iommu, domain->priv, paddr, size, dir); if (addr == bad_dma_address) goto out; if (iommu_has_npcache(iommu)) iommu_flush_pages(iommu, domain->id, addr, size); if (iommu->need_sync) iommu_completion_wait(iommu); out: spin_unlock_irqrestore(&domain->lock, flags); return addr; } /* * The exported unmap_single function for dma_ops. */ static void unmap_single(struct device *dev, dma_addr_t dma_addr, size_t size, int dir) { unsigned long flags; struct amd_iommu *iommu; struct protection_domain *domain; u16 devid; if (!get_device_resources(dev, &iommu, &domain, &devid)) /* device not handled by any AMD IOMMU */ return; spin_lock_irqsave(&domain->lock, flags); __unmap_single(iommu, domain->priv, dma_addr, size, dir); iommu_flush_pages(iommu, domain->id, dma_addr, size); if (iommu->need_sync) iommu_completion_wait(iommu); spin_unlock_irqrestore(&domain->lock, flags); } /* * This is a special map_sg function which is used if we should map a * device which is not handled by an AMD IOMMU in the system. */ static int map_sg_no_iommu(struct device *dev, struct scatterlist *sglist, int nelems, int dir) { struct scatterlist *s; int i; for_each_sg(sglist, s, nelems, i) { s->dma_address = (dma_addr_t)sg_phys(s); s->dma_length = s->length; } return nelems; } /* * The exported map_sg function for dma_ops (handles scatter-gather * lists). */ static int map_sg(struct device *dev, struct scatterlist *sglist, int nelems, int dir) { unsigned long flags; struct amd_iommu *iommu; struct protection_domain *domain; u16 devid; int i; struct scatterlist *s; phys_addr_t paddr; int mapped_elems = 0; get_device_resources(dev, &iommu, &domain, &devid); if (!iommu || !domain) return map_sg_no_iommu(dev, sglist, nelems, dir); spin_lock_irqsave(&domain->lock, flags); for_each_sg(sglist, s, nelems, i) { paddr = sg_phys(s); s->dma_address = __map_single(dev, iommu, domain->priv, paddr, s->length, dir); if (s->dma_address) { s->dma_length = s->length; mapped_elems++; } else goto unmap; if (iommu_has_npcache(iommu)) iommu_flush_pages(iommu, domain->id, s->dma_address, s->dma_length); } if (iommu->need_sync) iommu_completion_wait(iommu); out: spin_unlock_irqrestore(&domain->lock, flags); return mapped_elems; unmap: for_each_sg(sglist, s, mapped_elems, i) { if (s->dma_address) __unmap_single(iommu, domain->priv, s->dma_address, s->dma_length, dir); s->dma_address = s->dma_length = 0; } mapped_elems = 0; goto out; } /* * The exported map_sg function for dma_ops (handles scatter-gather * lists). */ static void unmap_sg(struct device *dev, struct scatterlist *sglist, int nelems, int dir) { unsigned long flags; struct amd_iommu *iommu; struct protection_domain *domain; struct scatterlist *s; u16 devid; int i; if (!get_device_resources(dev, &iommu, &domain, &devid)) return; spin_lock_irqsave(&domain->lock, flags); for_each_sg(sglist, s, nelems, i) { __unmap_single(iommu, domain->priv, s->dma_address, s->dma_length, dir); iommu_flush_pages(iommu, domain->id, s->dma_address, s->dma_length); s->dma_address = s->dma_length = 0; } if (iommu->need_sync) iommu_completion_wait(iommu); spin_unlock_irqrestore(&domain->lock, flags); } /* * The exported alloc_coherent function for dma_ops. */ static void *alloc_coherent(struct device *dev, size_t size, dma_addr_t *dma_addr, gfp_t flag) { unsigned long flags; void *virt_addr; struct amd_iommu *iommu; struct protection_domain *domain; u16 devid; phys_addr_t paddr; virt_addr = (void *)__get_free_pages(flag, get_order(size)); if (!virt_addr) return 0; memset(virt_addr, 0, size); paddr = virt_to_phys(virt_addr); get_device_resources(dev, &iommu, &domain, &devid); if (!iommu || !domain) { *dma_addr = (dma_addr_t)paddr; return virt_addr; } spin_lock_irqsave(&domain->lock, flags); *dma_addr = __map_single(dev, iommu, domain->priv, paddr, size, DMA_BIDIRECTIONAL); if (*dma_addr == bad_dma_address) { free_pages((unsigned long)virt_addr, get_order(size)); virt_addr = NULL; goto out; } if (iommu_has_npcache(iommu)) iommu_flush_pages(iommu, domain->id, *dma_addr, size); if (iommu->need_sync) iommu_completion_wait(iommu); out: spin_unlock_irqrestore(&domain->lock, flags); return virt_addr; } /* * The exported free_coherent function for dma_ops. * FIXME: fix the generic x86 DMA layer so that it actually calls that * function. */ static void free_coherent(struct device *dev, size_t size, void *virt_addr, dma_addr_t dma_addr) { unsigned long flags; struct amd_iommu *iommu; struct protection_domain *domain; u16 devid; get_device_resources(dev, &iommu, &domain, &devid); if (!iommu || !domain) goto free_mem; spin_lock_irqsave(&domain->lock, flags); __unmap_single(iommu, domain->priv, dma_addr, size, DMA_BIDIRECTIONAL); iommu_flush_pages(iommu, domain->id, dma_addr, size); if (iommu->need_sync) iommu_completion_wait(iommu); spin_unlock_irqrestore(&domain->lock, flags); free_mem: free_pages((unsigned long)virt_addr, get_order(size)); } /* * The function for pre-allocating protection domains. * * If the driver core informs the DMA layer if a driver grabs a device * we don't need to preallocate the protection domains anymore. * For now we have to. */ void prealloc_protection_domains(void) { struct pci_dev *dev = NULL; struct dma_ops_domain *dma_dom; struct amd_iommu *iommu; int order = amd_iommu_aperture_order; u16 devid; while ((dev = pci_get_device(PCI_ANY_ID, PCI_ANY_ID, dev)) != NULL) { devid = (dev->bus->number << 8) | dev->devfn; if (devid >= amd_iommu_last_bdf) continue; devid = amd_iommu_alias_table[devid]; if (domain_for_device(devid)) continue; iommu = amd_iommu_rlookup_table[devid]; if (!iommu) continue; dma_dom = dma_ops_domain_alloc(iommu, order); if (!dma_dom) continue; init_unity_mappings_for_device(dma_dom, devid); set_device_domain(iommu, &dma_dom->domain, devid); printk(KERN_INFO "AMD IOMMU: Allocated domain %d for device ", dma_dom->domain.id); print_devid(devid, 1); } } static struct dma_mapping_ops amd_iommu_dma_ops = { .alloc_coherent = alloc_coherent, .free_coherent = free_coherent, .map_single = map_single, .unmap_single = unmap_single, .map_sg = map_sg, .unmap_sg = unmap_sg, }; /* * The function which clues the AMD IOMMU driver into dma_ops. */ int __init amd_iommu_init_dma_ops(void) { struct amd_iommu *iommu; int order = amd_iommu_aperture_order; int ret; /* * first allocate a default protection domain for every IOMMU we * found in the system. Devices not assigned to any other * protection domain will be assigned to the default one. */ list_for_each_entry(iommu, &amd_iommu_list, list) { iommu->default_dom = dma_ops_domain_alloc(iommu, order); if (iommu->default_dom == NULL) return -ENOMEM; ret = iommu_init_unity_mappings(iommu); if (ret) goto free_domains; } /* * If device isolation is enabled, pre-allocate the protection * domains for each device. */ if (amd_iommu_isolate) prealloc_protection_domains(); iommu_detected = 1; force_iommu = 1; bad_dma_address = 0; #ifdef CONFIG_GART_IOMMU gart_iommu_aperture_disabled = 1; gart_iommu_aperture = 0; #endif /* Make the driver finally visible to the drivers */ dma_ops = &amd_iommu_dma_ops; return 0; free_domains: list_for_each_entry(iommu, &amd_iommu_list, list) { if (iommu->default_dom) dma_ops_domain_free(iommu->default_dom); } return ret; }