diff options
Diffstat (limited to 'drivers/iommu/dma-iommu.c')
| -rw-r--r-- | drivers/iommu/dma-iommu.c | 1258 |
1 files changed, 882 insertions, 376 deletions
diff --git a/drivers/iommu/dma-iommu.c b/drivers/iommu/dma-iommu.c index 7a9f0b0bddbd..c92088855450 100644 --- a/drivers/iommu/dma-iommu.c +++ b/drivers/iommu/dma-iommu.c @@ -17,20 +17,25 @@ #include <linux/gfp.h> #include <linux/huge_mm.h> #include <linux/iommu.h> +#include <linux/iommu-dma.h> #include <linux/iova.h> #include <linux/irq.h> #include <linux/list_sort.h> #include <linux/memremap.h> #include <linux/mm.h> #include <linux/mutex.h> +#include <linux/msi.h> #include <linux/of_iommu.h> #include <linux/pci.h> +#include <linux/pci-p2pdma.h> #include <linux/scatterlist.h> #include <linux/spinlock.h> #include <linux/swiotlb.h> #include <linux/vmalloc.h> +#include <trace/events/swiotlb.h> #include "dma-iommu.h" +#include "iommu-pages.h" struct iommu_dma_msi_page { struct list_head list; @@ -38,36 +43,42 @@ struct iommu_dma_msi_page { phys_addr_t phys; }; -enum iommu_dma_cookie_type { - IOMMU_DMA_IOVA_COOKIE, - IOMMU_DMA_MSI_COOKIE, +enum iommu_dma_queue_type { + IOMMU_DMA_OPTS_PER_CPU_QUEUE, + IOMMU_DMA_OPTS_SINGLE_QUEUE, +}; + +struct iommu_dma_options { + enum iommu_dma_queue_type qt; + size_t fq_size; + unsigned int fq_timeout; }; struct iommu_dma_cookie { - enum iommu_dma_cookie_type type; + struct iova_domain iovad; + struct list_head msi_page_list; + /* Flush queue */ union { - /* Full allocator for IOMMU_DMA_IOVA_COOKIE */ - struct { - struct iova_domain iovad; - - struct iova_fq __percpu *fq; /* Flush queue */ - /* Number of TLB flushes that have been started */ - atomic64_t fq_flush_start_cnt; - /* Number of TLB flushes that have been finished */ - atomic64_t fq_flush_finish_cnt; - /* Timer to regularily empty the flush queues */ - struct timer_list fq_timer; - /* 1 when timer is active, 0 when not */ - atomic_t fq_timer_on; - }; - /* Trivial linear page allocator for IOMMU_DMA_MSI_COOKIE */ - dma_addr_t msi_iova; + struct iova_fq *single_fq; + struct iova_fq __percpu *percpu_fq; }; - struct list_head msi_page_list; - + /* Number of TLB flushes that have been started */ + atomic64_t fq_flush_start_cnt; + /* Number of TLB flushes that have been finished */ + atomic64_t fq_flush_finish_cnt; + /* Timer to regularily empty the flush queues */ + struct timer_list fq_timer; + /* 1 when timer is active, 0 when not */ + atomic_t fq_timer_on; /* Domain for flush queue callback; NULL if flush queue not in use */ - struct iommu_domain *fq_domain; - struct mutex mutex; + struct iommu_domain *fq_domain; + /* Options for dma-iommu use */ + struct iommu_dma_options options; +}; + +struct iommu_dma_msi_cookie { + dma_addr_t msi_iova; + struct list_head msi_page_list; }; static DEFINE_STATIC_KEY_FALSE(iommu_deferred_attach_enabled); @@ -84,33 +95,36 @@ static int __init iommu_dma_forcedac_setup(char *str) early_param("iommu.forcedac", iommu_dma_forcedac_setup); /* Number of entries per flush queue */ -#define IOVA_FQ_SIZE 256 +#define IOVA_DEFAULT_FQ_SIZE 256 +#define IOVA_SINGLE_FQ_SIZE 32768 /* Timeout (in ms) after which entries are flushed from the queue */ -#define IOVA_FQ_TIMEOUT 10 +#define IOVA_DEFAULT_FQ_TIMEOUT 10 +#define IOVA_SINGLE_FQ_TIMEOUT 1000 /* Flush queue entry for deferred flushing */ struct iova_fq_entry { unsigned long iova_pfn; unsigned long pages; - struct list_head freelist; + struct iommu_pages_list freelist; u64 counter; /* Flush counter when this entry was added */ }; /* Per-CPU flush queue structure */ struct iova_fq { - struct iova_fq_entry entries[IOVA_FQ_SIZE]; - unsigned int head, tail; spinlock_t lock; + unsigned int head, tail; + unsigned int mod_mask; + struct iova_fq_entry entries[]; }; #define fq_ring_for_each(i, fq) \ - for ((i) = (fq)->head; (i) != (fq)->tail; (i) = ((i) + 1) % IOVA_FQ_SIZE) + for ((i) = (fq)->head; (i) != (fq)->tail; (i) = ((i) + 1) & (fq)->mod_mask) static inline bool fq_full(struct iova_fq *fq) { assert_spin_locked(&fq->lock); - return (((fq->tail + 1) % IOVA_FQ_SIZE) == fq->head); + return (((fq->tail + 1) & fq->mod_mask) == fq->head); } static inline unsigned int fq_ring_add(struct iova_fq *fq) @@ -119,12 +133,12 @@ static inline unsigned int fq_ring_add(struct iova_fq *fq) assert_spin_locked(&fq->lock); - fq->tail = (idx + 1) % IOVA_FQ_SIZE; + fq->tail = (idx + 1) & fq->mod_mask; return idx; } -static void fq_ring_free(struct iommu_dma_cookie *cookie, struct iova_fq *fq) +static void fq_ring_free_locked(struct iommu_dma_cookie *cookie, struct iova_fq *fq) { u64 counter = atomic64_read(&cookie->fq_flush_finish_cnt); unsigned int idx; @@ -136,15 +150,26 @@ static void fq_ring_free(struct iommu_dma_cookie *cookie, struct iova_fq *fq) if (fq->entries[idx].counter >= counter) break; - put_pages_list(&fq->entries[idx].freelist); + iommu_put_pages_list(&fq->entries[idx].freelist); free_iova_fast(&cookie->iovad, fq->entries[idx].iova_pfn, fq->entries[idx].pages); - fq->head = (fq->head + 1) % IOVA_FQ_SIZE; + fq->entries[idx].freelist = + IOMMU_PAGES_LIST_INIT(fq->entries[idx].freelist); + fq->head = (fq->head + 1) & fq->mod_mask; } } +static void fq_ring_free(struct iommu_dma_cookie *cookie, struct iova_fq *fq) +{ + unsigned long flags; + + spin_lock_irqsave(&fq->lock, flags); + fq_ring_free_locked(cookie, fq); + spin_unlock_irqrestore(&fq->lock, flags); +} + static void fq_flush_iotlb(struct iommu_dma_cookie *cookie) { atomic64_inc(&cookie->fq_flush_start_cnt); @@ -154,26 +179,24 @@ static void fq_flush_iotlb(struct iommu_dma_cookie *cookie) static void fq_flush_timeout(struct timer_list *t) { - struct iommu_dma_cookie *cookie = from_timer(cookie, t, fq_timer); + struct iommu_dma_cookie *cookie = timer_container_of(cookie, t, + fq_timer); int cpu; atomic_set(&cookie->fq_timer_on, 0); fq_flush_iotlb(cookie); - for_each_possible_cpu(cpu) { - unsigned long flags; - struct iova_fq *fq; - - fq = per_cpu_ptr(cookie->fq, cpu); - spin_lock_irqsave(&fq->lock, flags); - fq_ring_free(cookie, fq); - spin_unlock_irqrestore(&fq->lock, flags); + if (cookie->options.qt == IOMMU_DMA_OPTS_SINGLE_QUEUE) { + fq_ring_free(cookie, cookie->single_fq); + } else { + for_each_possible_cpu(cpu) + fq_ring_free(cookie, per_cpu_ptr(cookie->percpu_fq, cpu)); } } static void queue_iova(struct iommu_dma_cookie *cookie, unsigned long pfn, unsigned long pages, - struct list_head *freelist) + struct iommu_pages_list *freelist) { struct iova_fq *fq; unsigned long flags; @@ -188,7 +211,11 @@ static void queue_iova(struct iommu_dma_cookie *cookie, */ smp_mb(); - fq = raw_cpu_ptr(cookie->fq); + if (cookie->options.qt == IOMMU_DMA_OPTS_SINGLE_QUEUE) + fq = cookie->single_fq; + else + fq = raw_cpu_ptr(cookie->percpu_fq); + spin_lock_irqsave(&fq->lock, flags); /* @@ -196,11 +223,11 @@ static void queue_iova(struct iommu_dma_cookie *cookie, * flushed out on another CPU. This makes the fq_full() check below less * likely to be true. */ - fq_ring_free(cookie, fq); + fq_ring_free_locked(cookie, fq); if (fq_full(fq)) { fq_flush_iotlb(cookie); - fq_ring_free(cookie, fq); + fq_ring_free_locked(cookie, fq); } idx = fq_ring_add(fq); @@ -208,7 +235,7 @@ static void queue_iova(struct iommu_dma_cookie *cookie, fq->entries[idx].iova_pfn = pfn; fq->entries[idx].pages = pages; fq->entries[idx].counter = atomic64_read(&cookie->fq_flush_start_cnt); - list_splice(freelist, &fq->entries[idx].freelist); + iommu_pages_list_splice(freelist, &fq->entries[idx].freelist); spin_unlock_irqrestore(&fq->lock, flags); @@ -216,34 +243,96 @@ static void queue_iova(struct iommu_dma_cookie *cookie, if (!atomic_read(&cookie->fq_timer_on) && !atomic_xchg(&cookie->fq_timer_on, 1)) mod_timer(&cookie->fq_timer, - jiffies + msecs_to_jiffies(IOVA_FQ_TIMEOUT)); + jiffies + msecs_to_jiffies(cookie->options.fq_timeout)); } -static void iommu_dma_free_fq(struct iommu_dma_cookie *cookie) +static void iommu_dma_free_fq_single(struct iova_fq *fq) { - int cpu, idx; + int idx; - if (!cookie->fq) - return; + fq_ring_for_each(idx, fq) + iommu_put_pages_list(&fq->entries[idx].freelist); + vfree(fq); +} + +static void iommu_dma_free_fq_percpu(struct iova_fq __percpu *percpu_fq) +{ + int cpu, idx; - del_timer_sync(&cookie->fq_timer); /* The IOVAs will be torn down separately, so just free our queued pages */ for_each_possible_cpu(cpu) { - struct iova_fq *fq = per_cpu_ptr(cookie->fq, cpu); + struct iova_fq *fq = per_cpu_ptr(percpu_fq, cpu); fq_ring_for_each(idx, fq) - put_pages_list(&fq->entries[idx].freelist); + iommu_put_pages_list(&fq->entries[idx].freelist); } - free_percpu(cookie->fq); + free_percpu(percpu_fq); +} + +static void iommu_dma_free_fq(struct iommu_dma_cookie *cookie) +{ + if (!cookie->fq_domain) + return; + + timer_delete_sync(&cookie->fq_timer); + if (cookie->options.qt == IOMMU_DMA_OPTS_SINGLE_QUEUE) + iommu_dma_free_fq_single(cookie->single_fq); + else + iommu_dma_free_fq_percpu(cookie->percpu_fq); +} + +static void iommu_dma_init_one_fq(struct iova_fq *fq, size_t fq_size) +{ + int i; + + fq->head = 0; + fq->tail = 0; + fq->mod_mask = fq_size - 1; + + spin_lock_init(&fq->lock); + + for (i = 0; i < fq_size; i++) + fq->entries[i].freelist = + IOMMU_PAGES_LIST_INIT(fq->entries[i].freelist); +} + +static int iommu_dma_init_fq_single(struct iommu_dma_cookie *cookie) +{ + size_t fq_size = cookie->options.fq_size; + struct iova_fq *queue; + + queue = vmalloc(struct_size(queue, entries, fq_size)); + if (!queue) + return -ENOMEM; + iommu_dma_init_one_fq(queue, fq_size); + cookie->single_fq = queue; + + return 0; +} + +static int iommu_dma_init_fq_percpu(struct iommu_dma_cookie *cookie) +{ + size_t fq_size = cookie->options.fq_size; + struct iova_fq __percpu *queue; + int cpu; + + queue = __alloc_percpu(struct_size(queue, entries, fq_size), + __alignof__(*queue)); + if (!queue) + return -ENOMEM; + + for_each_possible_cpu(cpu) + iommu_dma_init_one_fq(per_cpu_ptr(queue, cpu), fq_size); + cookie->percpu_fq = queue; + return 0; } /* sysfs updates are serialised by the mutex of the group owning @domain */ int iommu_dma_init_fq(struct iommu_domain *domain) { struct iommu_dma_cookie *cookie = domain->iova_cookie; - struct iova_fq __percpu *queue; - int i, cpu; + int rc; if (cookie->fq_domain) return 0; @@ -251,26 +340,16 @@ int iommu_dma_init_fq(struct iommu_domain *domain) atomic64_set(&cookie->fq_flush_start_cnt, 0); atomic64_set(&cookie->fq_flush_finish_cnt, 0); - queue = alloc_percpu(struct iova_fq); - if (!queue) { + if (cookie->options.qt == IOMMU_DMA_OPTS_SINGLE_QUEUE) + rc = iommu_dma_init_fq_single(cookie); + else + rc = iommu_dma_init_fq_percpu(cookie); + + if (rc) { pr_warn("iova flush queue initialization failed\n"); return -ENOMEM; } - for_each_possible_cpu(cpu) { - struct iova_fq *fq = per_cpu_ptr(queue, cpu); - - fq->head = 0; - fq->tail = 0; - - spin_lock_init(&fq->lock); - - for (i = 0; i < IOVA_FQ_SIZE; i++) - INIT_LIST_HEAD(&fq->entries[i].freelist); - } - - cookie->fq = queue; - timer_setup(&cookie->fq_timer, fq_flush_timeout, 0); atomic_set(&cookie->fq_timer_on, 0); /* @@ -282,39 +361,24 @@ int iommu_dma_init_fq(struct iommu_domain *domain) return 0; } -static inline size_t cookie_msi_granule(struct iommu_dma_cookie *cookie) -{ - if (cookie->type == IOMMU_DMA_IOVA_COOKIE) - return cookie->iovad.granule; - return PAGE_SIZE; -} - -static struct iommu_dma_cookie *cookie_alloc(enum iommu_dma_cookie_type type) -{ - struct iommu_dma_cookie *cookie; - - cookie = kzalloc(sizeof(*cookie), GFP_KERNEL); - if (cookie) { - INIT_LIST_HEAD(&cookie->msi_page_list); - cookie->type = type; - } - return cookie; -} - /** * iommu_get_dma_cookie - Acquire DMA-API resources for a domain * @domain: IOMMU domain to prepare for DMA-API usage */ int iommu_get_dma_cookie(struct iommu_domain *domain) { - if (domain->iova_cookie) + struct iommu_dma_cookie *cookie; + + if (domain->cookie_type != IOMMU_COOKIE_NONE) return -EEXIST; - domain->iova_cookie = cookie_alloc(IOMMU_DMA_IOVA_COOKIE); - if (!domain->iova_cookie) + cookie = kzalloc(sizeof(*cookie), GFP_KERNEL); + if (!cookie) return -ENOMEM; - mutex_init(&domain->iova_cookie->mutex); + INIT_LIST_HEAD(&cookie->msi_page_list); + domain->cookie_type = IOMMU_COOKIE_DMA_IOVA; + domain->iova_cookie = cookie; return 0; } @@ -332,48 +396,56 @@ int iommu_get_dma_cookie(struct iommu_domain *domain) */ int iommu_get_msi_cookie(struct iommu_domain *domain, dma_addr_t base) { - struct iommu_dma_cookie *cookie; + struct iommu_dma_msi_cookie *cookie; if (domain->type != IOMMU_DOMAIN_UNMANAGED) return -EINVAL; - if (domain->iova_cookie) + if (domain->cookie_type != IOMMU_COOKIE_NONE) return -EEXIST; - cookie = cookie_alloc(IOMMU_DMA_MSI_COOKIE); + cookie = kzalloc(sizeof(*cookie), GFP_KERNEL); if (!cookie) return -ENOMEM; cookie->msi_iova = base; - domain->iova_cookie = cookie; + INIT_LIST_HEAD(&cookie->msi_page_list); + domain->cookie_type = IOMMU_COOKIE_DMA_MSI; + domain->msi_cookie = cookie; return 0; } EXPORT_SYMBOL(iommu_get_msi_cookie); /** * iommu_put_dma_cookie - Release a domain's DMA mapping resources - * @domain: IOMMU domain previously prepared by iommu_get_dma_cookie() or - * iommu_get_msi_cookie() + * @domain: IOMMU domain previously prepared by iommu_get_dma_cookie() */ void iommu_put_dma_cookie(struct iommu_domain *domain) { struct iommu_dma_cookie *cookie = domain->iova_cookie; struct iommu_dma_msi_page *msi, *tmp; - if (!cookie) - return; - - if (cookie->type == IOMMU_DMA_IOVA_COOKIE && cookie->iovad.granule) { + if (cookie->iovad.granule) { iommu_dma_free_fq(cookie); put_iova_domain(&cookie->iovad); } + list_for_each_entry_safe(msi, tmp, &cookie->msi_page_list, list) + kfree(msi); + kfree(cookie); +} + +/** + * iommu_put_msi_cookie - Release a domain's MSI mapping resources + * @domain: IOMMU domain previously prepared by iommu_get_msi_cookie() + */ +void iommu_put_msi_cookie(struct iommu_domain *domain) +{ + struct iommu_dma_msi_cookie *cookie = domain->msi_cookie; + struct iommu_dma_msi_page *msi, *tmp; - list_for_each_entry_safe(msi, tmp, &cookie->msi_page_list, list) { - list_del(&msi->list); + list_for_each_entry_safe(msi, tmp, &cookie->msi_page_list, list) kfree(msi); - } kfree(cookie); - domain->iova_cookie = NULL; } /** @@ -520,80 +592,124 @@ static bool dev_is_untrusted(struct device *dev) return dev_is_pci(dev) && to_pci_dev(dev)->untrusted; } -static bool dev_use_swiotlb(struct device *dev) +static bool dev_use_swiotlb(struct device *dev, size_t size, + enum dma_data_direction dir) +{ + return IS_ENABLED(CONFIG_SWIOTLB) && + (dev_is_untrusted(dev) || + dma_kmalloc_needs_bounce(dev, size, dir)); +} + +static bool dev_use_sg_swiotlb(struct device *dev, struct scatterlist *sg, + int nents, enum dma_data_direction dir) +{ + struct scatterlist *s; + int i; + + if (!IS_ENABLED(CONFIG_SWIOTLB)) + return false; + + if (dev_is_untrusted(dev)) + return true; + + /* + * If kmalloc() buffers are not DMA-safe for this device and + * direction, check the individual lengths in the sg list. If any + * element is deemed unsafe, use the swiotlb for bouncing. + */ + if (!dma_kmalloc_safe(dev, dir)) { + for_each_sg(sg, s, nents, i) + if (!dma_kmalloc_size_aligned(s->length)) + return true; + } + + return false; +} + +/** + * iommu_dma_init_options - Initialize dma-iommu options + * @options: The options to be initialized + * @dev: Device the options are set for + * + * This allows tuning dma-iommu specific to device properties + */ +static void iommu_dma_init_options(struct iommu_dma_options *options, + struct device *dev) { - return IS_ENABLED(CONFIG_SWIOTLB) && dev_is_untrusted(dev); + /* Shadowing IOTLB flushes do better with a single large queue */ + if (dev->iommu->shadow_on_flush) { + options->qt = IOMMU_DMA_OPTS_SINGLE_QUEUE; + options->fq_timeout = IOVA_SINGLE_FQ_TIMEOUT; + options->fq_size = IOVA_SINGLE_FQ_SIZE; + } else { + options->qt = IOMMU_DMA_OPTS_PER_CPU_QUEUE; + options->fq_size = IOVA_DEFAULT_FQ_SIZE; + options->fq_timeout = IOVA_DEFAULT_FQ_TIMEOUT; + } } /** * iommu_dma_init_domain - Initialise a DMA mapping domain * @domain: IOMMU domain previously prepared by iommu_get_dma_cookie() - * @base: IOVA at which the mappable address space starts - * @limit: Last address of the IOVA space * @dev: Device the domain is being initialised for * - * @base and @limit + 1 should be exact multiples of IOMMU page granularity to - * avoid rounding surprises. If necessary, we reserve the page at address 0 + * If the geometry and dma_range_map include address 0, we reserve that page * to ensure it is an invalid IOVA. It is safe to reinitialise a domain, but * any change which could make prior IOVAs invalid will fail. */ -static int iommu_dma_init_domain(struct iommu_domain *domain, dma_addr_t base, - dma_addr_t limit, struct device *dev) +static int iommu_dma_init_domain(struct iommu_domain *domain, struct device *dev) { struct iommu_dma_cookie *cookie = domain->iova_cookie; + const struct bus_dma_region *map = dev->dma_range_map; unsigned long order, base_pfn; struct iova_domain *iovad; int ret; - if (!cookie || cookie->type != IOMMU_DMA_IOVA_COOKIE) + if (!cookie || domain->cookie_type != IOMMU_COOKIE_DMA_IOVA) return -EINVAL; iovad = &cookie->iovad; /* Use the smallest supported page size for IOVA granularity */ order = __ffs(domain->pgsize_bitmap); - base_pfn = max_t(unsigned long, 1, base >> order); + base_pfn = 1; /* Check the domain allows at least some access to the device... */ - if (domain->geometry.force_aperture) { - if (base > domain->geometry.aperture_end || - limit < domain->geometry.aperture_start) { + if (map) { + if (dma_range_map_min(map) > domain->geometry.aperture_end || + dma_range_map_max(map) < domain->geometry.aperture_start) { pr_warn("specified DMA range outside IOMMU capability\n"); return -EFAULT; } - /* ...then finally give it a kicking to make sure it fits */ - base_pfn = max_t(unsigned long, base_pfn, - domain->geometry.aperture_start >> order); } + /* ...then finally give it a kicking to make sure it fits */ + base_pfn = max_t(unsigned long, base_pfn, + domain->geometry.aperture_start >> order); /* start_pfn is always nonzero for an already-initialised domain */ - mutex_lock(&cookie->mutex); if (iovad->start_pfn) { if (1UL << order != iovad->granule || base_pfn != iovad->start_pfn) { pr_warn("Incompatible range for DMA domain\n"); - ret = -EFAULT; - goto done_unlock; + return -EFAULT; } - ret = 0; - goto done_unlock; + return 0; } init_iova_domain(iovad, 1UL << order, base_pfn); ret = iova_domain_init_rcaches(iovad); if (ret) - goto done_unlock; + return ret; + + iommu_dma_init_options(&cookie->options, dev); /* If the FQ fails we can simply fall back to strict mode */ - if (domain->type == IOMMU_DOMAIN_DMA_FQ && iommu_dma_init_fq(domain)) + if (domain->type == IOMMU_DOMAIN_DMA_FQ && + (!device_iommu_capable(dev, IOMMU_CAP_DEFERRED_FLUSH) || iommu_dma_init_fq(domain))) domain->type = IOMMU_DOMAIN_DMA; - ret = iova_reserve_iommu_regions(dev, domain); - -done_unlock: - mutex_unlock(&cookie->mutex); - return ret; + return iova_reserve_iommu_regions(dev, domain); } /** @@ -608,7 +724,12 @@ done_unlock: static int dma_info_to_prot(enum dma_data_direction dir, bool coherent, unsigned long attrs) { - int prot = coherent ? IOMMU_CACHE : 0; + int prot; + + if (attrs & DMA_ATTR_MMIO) + prot = IOMMU_MMIO; + else + prot = coherent ? IOMMU_CACHE : 0; if (attrs & DMA_ATTR_PRIVILEGED) prot |= IOMMU_PRIV; @@ -630,11 +751,11 @@ static dma_addr_t iommu_dma_alloc_iova(struct iommu_domain *domain, { struct iommu_dma_cookie *cookie = domain->iova_cookie; struct iova_domain *iovad = &cookie->iovad; - unsigned long shift, iova_len, iova = 0; + unsigned long shift, iova_len, iova; - if (cookie->type == IOMMU_DMA_MSI_COOKIE) { - cookie->msi_iova += size; - return cookie->msi_iova - size; + if (domain->cookie_type == IOMMU_COOKIE_DMA_MSI) { + domain->msi_cookie->msi_iova += size; + return domain->msi_cookie->msi_iova - size; } shift = iova_shift(iovad); @@ -645,28 +766,42 @@ static dma_addr_t iommu_dma_alloc_iova(struct iommu_domain *domain, if (domain->geometry.force_aperture) dma_limit = min(dma_limit, (u64)domain->geometry.aperture_end); - /* Try to get PCI devices a SAC address */ - if (dma_limit > DMA_BIT_MASK(32) && !iommu_dma_forcedac && dev_is_pci(dev)) + /* + * Try to use all the 32-bit PCI addresses first. The original SAC vs. + * DAC reasoning loses relevance with PCIe, but enough hardware and + * firmware bugs are still lurking out there that it's safest not to + * venture into the 64-bit space until necessary. + * + * If your device goes wrong after seeing the notice then likely either + * its driver is not setting DMA masks accurately, the hardware has + * some inherent bug in handling >32-bit addresses, or not all the + * expected address bits are wired up between the device and the IOMMU. + */ + if (dma_limit > DMA_BIT_MASK(32) && dev->iommu->pci_32bit_workaround) { iova = alloc_iova_fast(iovad, iova_len, DMA_BIT_MASK(32) >> shift, false); + if (iova) + goto done; - if (!iova) - iova = alloc_iova_fast(iovad, iova_len, dma_limit >> shift, - true); + dev->iommu->pci_32bit_workaround = false; + dev_notice(dev, "Using %d-bit DMA addresses\n", bits_per(dma_limit)); + } + iova = alloc_iova_fast(iovad, iova_len, dma_limit >> shift, true); +done: return (dma_addr_t)iova << shift; } -static void iommu_dma_free_iova(struct iommu_dma_cookie *cookie, - dma_addr_t iova, size_t size, struct iommu_iotlb_gather *gather) +static void iommu_dma_free_iova(struct iommu_domain *domain, dma_addr_t iova, + size_t size, struct iommu_iotlb_gather *gather) { - struct iova_domain *iovad = &cookie->iovad; + struct iova_domain *iovad = &domain->iova_cookie->iovad; /* The MSI case is only ever cleaning up its most recent allocation */ - if (cookie->type == IOMMU_DMA_MSI_COOKIE) - cookie->msi_iova -= size; + if (domain->cookie_type == IOMMU_COOKIE_DMA_MSI) + domain->msi_cookie->msi_iova -= size; else if (gather && gather->queued) - queue_iova(cookie, iova_pfn(iovad, iova), + queue_iova(domain->iova_cookie, iova_pfn(iovad, iova), size >> iova_shift(iovad), &gather->freelist); else @@ -694,7 +829,7 @@ static void __iommu_dma_unmap(struct device *dev, dma_addr_t dma_addr, if (!iotlb_gather.queued) iommu_iotlb_sync(domain, &iotlb_gather); - iommu_dma_free_iova(cookie, dma_addr, size, &iotlb_gather); + iommu_dma_free_iova(domain, dma_addr, size, &iotlb_gather); } static dma_addr_t __iommu_dma_map(struct device *dev, phys_addr_t phys, @@ -710,6 +845,11 @@ static dma_addr_t __iommu_dma_map(struct device *dev, phys_addr_t phys, iommu_deferred_attach(dev, domain)) return DMA_MAPPING_ERROR; + /* If anyone ever wants this we'd need support in the IOVA allocator */ + if (dev_WARN_ONCE(dev, dma_get_min_align_mask(dev) > iova_mask(iovad), + "Unsupported alignment constraint\n")) + return DMA_MAPPING_ERROR; + size = iova_align(iovad, size + iova_off); iova = iommu_dma_alloc_iova(domain, size, dma_mask, dev); @@ -717,7 +857,7 @@ static dma_addr_t __iommu_dma_map(struct device *dev, phys_addr_t phys, return DMA_MAPPING_ERROR; if (iommu_map(domain, iova, phys - iova_off, size, prot, GFP_ATOMIC)) { - iommu_dma_free_iova(cookie, iova, size, NULL); + iommu_dma_free_iova(domain, iova, size, NULL); return DMA_MAPPING_ERROR; } return iova + iova_off; @@ -736,7 +876,7 @@ static struct page **__iommu_dma_alloc_pages(struct device *dev, struct page **pages; unsigned int i = 0, nid = dev_to_node(dev); - order_mask &= GENMASK(MAX_ORDER, 0); + order_mask &= GENMASK(MAX_PAGE_ORDER, 0); if (!order_mask) return NULL; @@ -787,8 +927,7 @@ static struct page **__iommu_dma_alloc_pages(struct device *dev, * but an IOMMU which supports smaller pages might not map the whole thing. */ static struct page **__iommu_dma_alloc_noncontiguous(struct device *dev, - size_t size, struct sg_table *sgt, gfp_t gfp, pgprot_t prot, - unsigned long attrs) + size_t size, struct sg_table *sgt, gfp_t gfp, unsigned long attrs) { struct iommu_domain *domain = iommu_get_dma_domain(dev); struct iommu_dma_cookie *cookie = domain->iova_cookie; @@ -855,22 +994,21 @@ static struct page **__iommu_dma_alloc_noncontiguous(struct device *dev, out_free_sg: sg_free_table(sgt); out_free_iova: - iommu_dma_free_iova(cookie, iova, size, NULL); + iommu_dma_free_iova(domain, iova, size, NULL); out_free_pages: __iommu_dma_free_pages(pages, count); return NULL; } static void *iommu_dma_alloc_remap(struct device *dev, size_t size, - dma_addr_t *dma_handle, gfp_t gfp, pgprot_t prot, - unsigned long attrs) + dma_addr_t *dma_handle, gfp_t gfp, unsigned long attrs) { struct page **pages; struct sg_table sgt; void *vaddr; + pgprot_t prot = dma_pgprot(dev, PAGE_KERNEL, attrs); - pages = __iommu_dma_alloc_noncontiguous(dev, size, &sgt, gfp, prot, - attrs); + pages = __iommu_dma_alloc_noncontiguous(dev, size, &sgt, gfp, attrs); if (!pages) return NULL; *dma_handle = sgt.sgl->dma_address; @@ -887,9 +1025,23 @@ out_unmap: return NULL; } -static struct sg_table *iommu_dma_alloc_noncontiguous(struct device *dev, - size_t size, enum dma_data_direction dir, gfp_t gfp, - unsigned long attrs) +/* + * This is the actual return value from the iommu_dma_alloc_noncontiguous. + * + * The users of the DMA API should only care about the sg_table, but to make + * the DMA-API internal vmaping and freeing easier we stash away the page + * array as well (except for the fallback case). This can go away any time, + * e.g. when a vmap-variant that takes a scatterlist comes along. + */ +struct dma_sgt_handle { + struct sg_table sgt; + struct page **pages; +}; +#define sgt_handle(sgt) \ + container_of((sgt), struct dma_sgt_handle, sgt) + +struct sg_table *iommu_dma_alloc_noncontiguous(struct device *dev, size_t size, + enum dma_data_direction dir, gfp_t gfp, unsigned long attrs) { struct dma_sgt_handle *sh; @@ -897,8 +1049,7 @@ static struct sg_table *iommu_dma_alloc_noncontiguous(struct device *dev, if (!sh) return NULL; - sh->pages = __iommu_dma_alloc_noncontiguous(dev, size, &sh->sgt, gfp, - PAGE_KERNEL, attrs); + sh->pages = __iommu_dma_alloc_noncontiguous(dev, size, &sh->sgt, gfp, attrs); if (!sh->pages) { kfree(sh); return NULL; @@ -906,7 +1057,7 @@ static struct sg_table *iommu_dma_alloc_noncontiguous(struct device *dev, return &sh->sgt; } -static void iommu_dma_free_noncontiguous(struct device *dev, size_t size, +void iommu_dma_free_noncontiguous(struct device *dev, size_t size, struct sg_table *sgt, enum dma_data_direction dir) { struct dma_sgt_handle *sh = sgt_handle(sgt); @@ -917,46 +1068,61 @@ static void iommu_dma_free_noncontiguous(struct device *dev, size_t size, kfree(sh); } -static void iommu_dma_sync_single_for_cpu(struct device *dev, - dma_addr_t dma_handle, size_t size, enum dma_data_direction dir) +void *iommu_dma_vmap_noncontiguous(struct device *dev, size_t size, + struct sg_table *sgt) +{ + unsigned long count = PAGE_ALIGN(size) >> PAGE_SHIFT; + + return vmap(sgt_handle(sgt)->pages, count, VM_MAP, PAGE_KERNEL); +} + +int iommu_dma_mmap_noncontiguous(struct device *dev, struct vm_area_struct *vma, + size_t size, struct sg_table *sgt) +{ + unsigned long count = PAGE_ALIGN(size) >> PAGE_SHIFT; + + if (vma->vm_pgoff >= count || vma_pages(vma) > count - vma->vm_pgoff) + return -ENXIO; + return vm_map_pages(vma, sgt_handle(sgt)->pages, count); +} + +void iommu_dma_sync_single_for_cpu(struct device *dev, dma_addr_t dma_handle, + size_t size, enum dma_data_direction dir) { phys_addr_t phys; - if (dev_is_dma_coherent(dev) && !dev_use_swiotlb(dev)) + if (dev_is_dma_coherent(dev) && !dev_use_swiotlb(dev, size, dir)) return; phys = iommu_iova_to_phys(iommu_get_dma_domain(dev), dma_handle); if (!dev_is_dma_coherent(dev)) arch_sync_dma_for_cpu(phys, size, dir); - if (is_swiotlb_buffer(dev, phys)) - swiotlb_sync_single_for_cpu(dev, phys, size, dir); + swiotlb_sync_single_for_cpu(dev, phys, size, dir); } -static void iommu_dma_sync_single_for_device(struct device *dev, - dma_addr_t dma_handle, size_t size, enum dma_data_direction dir) +void iommu_dma_sync_single_for_device(struct device *dev, dma_addr_t dma_handle, + size_t size, enum dma_data_direction dir) { phys_addr_t phys; - if (dev_is_dma_coherent(dev) && !dev_use_swiotlb(dev)) + if (dev_is_dma_coherent(dev) && !dev_use_swiotlb(dev, size, dir)) return; phys = iommu_iova_to_phys(iommu_get_dma_domain(dev), dma_handle); - if (is_swiotlb_buffer(dev, phys)) - swiotlb_sync_single_for_device(dev, phys, size, dir); + swiotlb_sync_single_for_device(dev, phys, size, dir); if (!dev_is_dma_coherent(dev)) arch_sync_dma_for_device(phys, size, dir); } -static void iommu_dma_sync_sg_for_cpu(struct device *dev, - struct scatterlist *sgl, int nelems, - enum dma_data_direction dir) +void iommu_dma_sync_sg_for_cpu(struct device *dev, struct scatterlist *sgl, + int nelems, enum dma_data_direction dir) { struct scatterlist *sg; int i; - if (dev_use_swiotlb(dev)) + if (sg_dma_is_swiotlb(sgl)) for_each_sg(sgl, sg, nelems, i) iommu_dma_sync_single_for_cpu(dev, sg_dma_address(sg), sg->length, dir); @@ -965,14 +1131,13 @@ static void iommu_dma_sync_sg_for_cpu(struct device *dev, arch_sync_dma_for_cpu(sg_phys(sg), sg->length, dir); } -static void iommu_dma_sync_sg_for_device(struct device *dev, - struct scatterlist *sgl, int nelems, - enum dma_data_direction dir) +void iommu_dma_sync_sg_for_device(struct device *dev, struct scatterlist *sgl, + int nelems, enum dma_data_direction dir) { struct scatterlist *sg; int i; - if (dev_use_swiotlb(dev)) + if (sg_dma_is_swiotlb(sgl)) for_each_sg(sgl, sg, nelems, i) iommu_dma_sync_single_for_device(dev, sg_dma_address(sg), @@ -982,11 +1147,57 @@ static void iommu_dma_sync_sg_for_device(struct device *dev, arch_sync_dma_for_device(sg_phys(sg), sg->length, dir); } -static dma_addr_t iommu_dma_map_page(struct device *dev, struct page *page, - unsigned long offset, size_t size, enum dma_data_direction dir, - unsigned long attrs) +static phys_addr_t iommu_dma_map_swiotlb(struct device *dev, phys_addr_t phys, + size_t size, enum dma_data_direction dir, unsigned long attrs) +{ + struct iommu_domain *domain = iommu_get_dma_domain(dev); + struct iova_domain *iovad = &domain->iova_cookie->iovad; + + if (!is_swiotlb_active(dev)) { + dev_warn_once(dev, "DMA bounce buffers are inactive, unable to map unaligned transaction.\n"); + return (phys_addr_t)DMA_MAPPING_ERROR; + } + + trace_swiotlb_bounced(dev, phys, size); + + phys = swiotlb_tbl_map_single(dev, phys, size, iova_mask(iovad), dir, + attrs); + + /* + * Untrusted devices should not see padding areas with random leftover + * kernel data, so zero the pre- and post-padding. + * swiotlb_tbl_map_single() has initialized the bounce buffer proper to + * the contents of the original memory buffer. + */ + if (phys != (phys_addr_t)DMA_MAPPING_ERROR && dev_is_untrusted(dev)) { + size_t start, virt = (size_t)phys_to_virt(phys); + + /* Pre-padding */ + start = iova_align_down(iovad, virt); + memset((void *)start, 0, virt - start); + + /* Post-padding */ + start = virt + size; + memset((void *)start, 0, iova_align(iovad, start) - start); + } + + return phys; +} + +/* + * Checks if a physical buffer has unaligned boundaries with respect to + * the IOMMU granule. Returns non-zero if either the start or end + * address is not aligned to the granule boundary. + */ +static inline size_t iova_unaligned(struct iova_domain *iovad, phys_addr_t phys, + size_t size) +{ + return iova_offset(iovad, phys | size); +} + +dma_addr_t iommu_dma_map_phys(struct device *dev, phys_addr_t phys, size_t size, + enum dma_data_direction dir, unsigned long attrs) { - phys_addr_t phys = page_to_phys(page) + offset; bool coherent = dev_is_dma_coherent(dev); int prot = dma_info_to_prot(dir, coherent, attrs); struct iommu_domain *domain = iommu_get_dma_domain(dev); @@ -995,54 +1206,39 @@ static dma_addr_t iommu_dma_map_page(struct device *dev, struct page *page, dma_addr_t iova, dma_mask = dma_get_mask(dev); /* - * If both the physical buffer start address and size are - * page aligned, we don't need to use a bounce page. + * If both the physical buffer start address and size are page aligned, + * we don't need to use a bounce page. */ - if (dev_use_swiotlb(dev) && iova_offset(iovad, phys | size)) { - void *padding_start; - size_t padding_size, aligned_size; - - if (!is_swiotlb_active(dev)) { - dev_warn_once(dev, "DMA bounce buffers are inactive, unable to map unaligned transaction.\n"); + if (dev_use_swiotlb(dev, size, dir) && + iova_unaligned(iovad, phys, size)) { + if (attrs & DMA_ATTR_MMIO) return DMA_MAPPING_ERROR; - } - - aligned_size = iova_align(iovad, size); - phys = swiotlb_tbl_map_single(dev, phys, size, aligned_size, - iova_mask(iovad), dir, attrs); - if (phys == DMA_MAPPING_ERROR) + phys = iommu_dma_map_swiotlb(dev, phys, size, dir, attrs); + if (phys == (phys_addr_t)DMA_MAPPING_ERROR) return DMA_MAPPING_ERROR; - - /* Cleanup the padding area. */ - padding_start = phys_to_virt(phys); - padding_size = aligned_size; - - if (!(attrs & DMA_ATTR_SKIP_CPU_SYNC) && - (dir == DMA_TO_DEVICE || dir == DMA_BIDIRECTIONAL)) { - padding_start += size; - padding_size -= size; - } - - memset(padding_start, 0, padding_size); } - if (!coherent && !(attrs & DMA_ATTR_SKIP_CPU_SYNC)) + if (!coherent && !(attrs & (DMA_ATTR_SKIP_CPU_SYNC | DMA_ATTR_MMIO))) arch_sync_dma_for_device(phys, size, dir); iova = __iommu_dma_map(dev, phys, size, prot, dma_mask); - if (iova == DMA_MAPPING_ERROR && is_swiotlb_buffer(dev, phys)) + if (iova == DMA_MAPPING_ERROR && !(attrs & DMA_ATTR_MMIO)) swiotlb_tbl_unmap_single(dev, phys, size, dir, attrs); return iova; } -static void iommu_dma_unmap_page(struct device *dev, dma_addr_t dma_handle, +void iommu_dma_unmap_phys(struct device *dev, dma_addr_t dma_handle, size_t size, enum dma_data_direction dir, unsigned long attrs) { - struct iommu_domain *domain = iommu_get_dma_domain(dev); phys_addr_t phys; - phys = iommu_iova_to_phys(domain, dma_handle); + if (attrs & DMA_ATTR_MMIO) { + __iommu_dma_unmap(dev, dma_handle, size); + return; + } + + phys = iommu_iova_to_phys(iommu_get_dma_domain(dev), dma_handle); if (WARN_ON(!phys)) return; @@ -1051,8 +1247,7 @@ static void iommu_dma_unmap_page(struct device *dev, dma_addr_t dma_handle, __iommu_dma_unmap(dev, dma_handle, size); - if (unlikely(is_swiotlb_buffer(dev, phys))) - swiotlb_tbl_unmap_single(dev, phys, size, dir, attrs); + swiotlb_tbl_unmap_single(dev, phys, size, dir, attrs); } /* @@ -1080,7 +1275,7 @@ static int __finalise_sg(struct device *dev, struct scatterlist *sg, int nents, sg_dma_address(s) = DMA_MAPPING_ERROR; sg_dma_len(s) = 0; - if (sg_is_dma_bus_address(s)) { + if (sg_dma_is_bus_address(s)) { if (i > 0) cur = sg_next(cur); @@ -1136,7 +1331,7 @@ static void __invalidate_sg(struct scatterlist *sg, int nents) int i; for_each_sg(sg, s, nents, i) { - if (sg_is_dma_bus_address(s)) { + if (sg_dma_is_bus_address(s)) { sg_dma_unmark_bus_address(s); } else { if (sg_dma_address(s) != DMA_MAPPING_ERROR) @@ -1156,7 +1351,7 @@ static void iommu_dma_unmap_sg_swiotlb(struct device *dev, struct scatterlist *s int i; for_each_sg(sg, s, nents, i) - iommu_dma_unmap_page(dev, sg_dma_address(s), + iommu_dma_unmap_phys(dev, sg_dma_address(s), sg_dma_len(s), dir, attrs); } @@ -1166,9 +1361,11 @@ static int iommu_dma_map_sg_swiotlb(struct device *dev, struct scatterlist *sg, struct scatterlist *s; int i; + sg_dma_mark_swiotlb(sg); + for_each_sg(sg, s, nents, i) { - sg_dma_address(s) = iommu_dma_map_page(dev, sg_page(s), - s->offset, s->length, dir, attrs); + sg_dma_address(s) = iommu_dma_map_phys(dev, sg_phys(s), + s->length, dir, attrs); if (sg_dma_address(s) == DMA_MAPPING_ERROR) goto out_unmap; sg_dma_len(s) = s->length; @@ -1188,8 +1385,8 @@ out_unmap: * impedance-matching, to be able to hand off a suitably-aligned list, * but still preserve the original offsets and sizes for the caller. */ -static int iommu_dma_map_sg(struct device *dev, struct scatterlist *sg, - int nents, enum dma_data_direction dir, unsigned long attrs) +int iommu_dma_map_sg(struct device *dev, struct scatterlist *sg, int nents, + enum dma_data_direction dir, unsigned long attrs) { struct iommu_domain *domain = iommu_get_dma_domain(dev); struct iommu_dma_cookie *cookie = domain->iova_cookie; @@ -1197,7 +1394,6 @@ static int iommu_dma_map_sg(struct device *dev, struct scatterlist *sg, struct scatterlist *s, *prev = NULL; int prot = dma_info_to_prot(dir, dev_is_dma_coherent(dev), attrs); struct pci_p2pdma_map_state p2pdma_state = {}; - enum pci_p2pdma_map_type map; dma_addr_t iova; size_t iova_len = 0; unsigned long mask = dma_get_seg_boundary(dev); @@ -1210,7 +1406,7 @@ static int iommu_dma_map_sg(struct device *dev, struct scatterlist *sg, goto out; } - if (dev_use_swiotlb(dev)) + if (dev_use_sg_swiotlb(dev, sg, nents, dir)) return iommu_dma_map_sg_swiotlb(dev, sg, nents, dir, attrs); if (!(attrs & DMA_ATTR_SKIP_CPU_SYNC)) @@ -1227,28 +1423,30 @@ static int iommu_dma_map_sg(struct device *dev, struct scatterlist *sg, size_t s_length = s->length; size_t pad_len = (mask - iova_len + 1) & mask; - if (is_pci_p2pdma_page(sg_page(s))) { - map = pci_p2pdma_map_segment(&p2pdma_state, dev, s); - switch (map) { - case PCI_P2PDMA_MAP_BUS_ADDR: - /* - * iommu_map_sg() will skip this segment as - * it is marked as a bus address, - * __finalise_sg() will copy the dma address - * into the output segment. - */ - continue; - case PCI_P2PDMA_MAP_THRU_HOST_BRIDGE: - /* - * Mapping through host bridge should be - * mapped with regular IOVAs, thus we - * do nothing here and continue below. - */ - break; - default: - ret = -EREMOTEIO; - goto out_restore_sg; - } + switch (pci_p2pdma_state(&p2pdma_state, dev, sg_page(s))) { + case PCI_P2PDMA_MAP_THRU_HOST_BRIDGE: + /* + * Mapping through host bridge should be mapped with + * regular IOVAs, thus we do nothing here and continue + * below. + */ + break; + case PCI_P2PDMA_MAP_NONE: + break; + case PCI_P2PDMA_MAP_BUS_ADDR: + /* + * iommu_map_sg() will skip this segment as it is marked + * as a bus address, __finalise_sg() will copy the dma + * address into the output segment. + */ + s->dma_address = pci_p2pdma_bus_addr_map( + p2pdma_state.mem, sg_phys(s)); + sg_dma_len(s) = sg->length; + sg_dma_mark_bus_address(s); + continue; + default: + ret = -EREMOTEIO; + goto out_restore_sg; } sg_dma_address(s) = s_iova_off; @@ -1299,7 +1497,7 @@ static int iommu_dma_map_sg(struct device *dev, struct scatterlist *sg, return __finalise_sg(dev, sg, nents, iova); out_free_iova: - iommu_dma_free_iova(cookie, iova, iova_len, NULL); + iommu_dma_free_iova(domain, iova, iova_len, NULL); out_restore_sg: __invalidate_sg(sg, nents); out: @@ -1308,14 +1506,14 @@ out: return ret; } -static void iommu_dma_unmap_sg(struct device *dev, struct scatterlist *sg, - int nents, enum dma_data_direction dir, unsigned long attrs) +void iommu_dma_unmap_sg(struct device *dev, struct scatterlist *sg, int nents, + enum dma_data_direction dir, unsigned long attrs) { dma_addr_t end = 0, start; struct scatterlist *tmp; int i; - if (dev_use_swiotlb(dev)) { + if (sg_dma_is_swiotlb(sg)) { iommu_dma_unmap_sg_swiotlb(dev, sg, nents, dir, attrs); return; } @@ -1329,7 +1527,7 @@ static void iommu_dma_unmap_sg(struct device *dev, struct scatterlist *sg, * just have to be determined. */ for_each_sg(sg, tmp, nents, i) { - if (sg_is_dma_bus_address(tmp)) { + if (sg_dma_is_bus_address(tmp)) { sg_dma_unmark_bus_address(tmp); continue; } @@ -1343,7 +1541,7 @@ static void iommu_dma_unmap_sg(struct device *dev, struct scatterlist *sg, nents -= i; for_each_sg(tmp, tmp, nents, i) { - if (sg_is_dma_bus_address(tmp)) { + if (sg_dma_is_bus_address(tmp)) { sg_dma_unmark_bus_address(tmp); continue; } @@ -1358,20 +1556,6 @@ static void iommu_dma_unmap_sg(struct device *dev, struct scatterlist *sg, __iommu_dma_unmap(dev, start, end - start); } -static dma_addr_t iommu_dma_map_resource(struct device *dev, phys_addr_t phys, - size_t size, enum dma_data_direction dir, unsigned long attrs) -{ - return __iommu_dma_map(dev, phys, size, - dma_info_to_prot(dir, false, attrs) | IOMMU_MMIO, - dma_get_mask(dev)); -} - -static void iommu_dma_unmap_resource(struct device *dev, dma_addr_t handle, - size_t size, enum dma_data_direction dir, unsigned long attrs) -{ - __iommu_dma_unmap(dev, handle, size); -} - static void __iommu_dma_free(struct device *dev, size_t size, void *cpu_addr) { size_t alloc_size = PAGE_ALIGN(size); @@ -1403,7 +1587,7 @@ static void __iommu_dma_free(struct device *dev, size_t size, void *cpu_addr) dma_free_contiguous(dev, page, alloc_size); } -static void iommu_dma_free(struct device *dev, size_t size, void *cpu_addr, +void iommu_dma_free(struct device *dev, size_t size, void *cpu_addr, dma_addr_t handle, unsigned long attrs) { __iommu_dma_unmap(dev, handle, size); @@ -1447,8 +1631,8 @@ out_free_pages: return NULL; } -static void *iommu_dma_alloc(struct device *dev, size_t size, - dma_addr_t *handle, gfp_t gfp, unsigned long attrs) +void *iommu_dma_alloc(struct device *dev, size_t size, dma_addr_t *handle, + gfp_t gfp, unsigned long attrs) { bool coherent = dev_is_dma_coherent(dev); int ioprot = dma_info_to_prot(DMA_BIDIRECTIONAL, coherent, attrs); @@ -1459,8 +1643,7 @@ static void *iommu_dma_alloc(struct device *dev, size_t size, if (gfpflags_allow_blocking(gfp) && !(attrs & DMA_ATTR_FORCE_CONTIGUOUS)) { - return iommu_dma_alloc_remap(dev, size, handle, gfp, - dma_pgprot(dev, PAGE_KERNEL, attrs), attrs); + return iommu_dma_alloc_remap(dev, size, handle, gfp, attrs); } if (IS_ENABLED(CONFIG_DMA_DIRECT_REMAP) && @@ -1482,7 +1665,7 @@ static void *iommu_dma_alloc(struct device *dev, size_t size, return cpu_addr; } -static int iommu_dma_mmap(struct device *dev, struct vm_area_struct *vma, +int iommu_dma_mmap(struct device *dev, struct vm_area_struct *vma, void *cpu_addr, dma_addr_t dma_addr, size_t size, unsigned long attrs) { @@ -1513,7 +1696,7 @@ static int iommu_dma_mmap(struct device *dev, struct vm_area_struct *vma, vma->vm_page_prot); } -static int iommu_dma_get_sgtable(struct device *dev, struct sg_table *sgt, +int iommu_dma_get_sgtable(struct device *dev, struct sg_table *sgt, void *cpu_addr, dma_addr_t dma_addr, size_t size, unsigned long attrs) { @@ -1540,81 +1723,439 @@ static int iommu_dma_get_sgtable(struct device *dev, struct sg_table *sgt, return ret; } -static unsigned long iommu_dma_get_merge_boundary(struct device *dev) +unsigned long iommu_dma_get_merge_boundary(struct device *dev) { struct iommu_domain *domain = iommu_get_dma_domain(dev); return (1UL << __ffs(domain->pgsize_bitmap)) - 1; } -static size_t iommu_dma_opt_mapping_size(void) +size_t iommu_dma_opt_mapping_size(void) { return iova_rcache_range(); } -static const struct dma_map_ops iommu_dma_ops = { - .flags = DMA_F_PCI_P2PDMA_SUPPORTED, - .alloc = iommu_dma_alloc, - .free = iommu_dma_free, - .alloc_pages = dma_common_alloc_pages, - .free_pages = dma_common_free_pages, - .alloc_noncontiguous = iommu_dma_alloc_noncontiguous, - .free_noncontiguous = iommu_dma_free_noncontiguous, - .mmap = iommu_dma_mmap, - .get_sgtable = iommu_dma_get_sgtable, - .map_page = iommu_dma_map_page, - .unmap_page = iommu_dma_unmap_page, - .map_sg = iommu_dma_map_sg, - .unmap_sg = iommu_dma_unmap_sg, - .sync_single_for_cpu = iommu_dma_sync_single_for_cpu, - .sync_single_for_device = iommu_dma_sync_single_for_device, - .sync_sg_for_cpu = iommu_dma_sync_sg_for_cpu, - .sync_sg_for_device = iommu_dma_sync_sg_for_device, - .map_resource = iommu_dma_map_resource, - .unmap_resource = iommu_dma_unmap_resource, - .get_merge_boundary = iommu_dma_get_merge_boundary, - .opt_mapping_size = iommu_dma_opt_mapping_size, -}; +size_t iommu_dma_max_mapping_size(struct device *dev) +{ + if (dev_is_untrusted(dev)) + return swiotlb_max_mapping_size(dev); -/* - * The IOMMU core code allocates the default DMA domain, which the underlying - * IOMMU driver needs to support via the dma-iommu layer. + return SIZE_MAX; +} + +/** + * dma_iova_try_alloc - Try to allocate an IOVA space + * @dev: Device to allocate the IOVA space for + * @state: IOVA state + * @phys: physical address + * @size: IOVA size + * + * Check if @dev supports the IOVA-based DMA API, and if yes allocate IOVA space + * for the given base address and size. + * + * Note: @phys is only used to calculate the IOVA alignment. Callers that always + * do PAGE_SIZE aligned transfers can safely pass 0 here. + * + * Returns %true if the IOVA-based DMA API can be used and IOVA space has been + * allocated, or %false if the regular DMA API should be used. */ -void iommu_setup_dma_ops(struct device *dev, u64 dma_base, u64 dma_limit) +bool dma_iova_try_alloc(struct device *dev, struct dma_iova_state *state, + phys_addr_t phys, size_t size) { - struct iommu_domain *domain = iommu_get_domain_for_dev(dev); + struct iommu_dma_cookie *cookie; + struct iommu_domain *domain; + struct iova_domain *iovad; + size_t iova_off; + dma_addr_t addr; - if (!domain) - goto out_err; + memset(state, 0, sizeof(*state)); + if (!use_dma_iommu(dev)) + return false; + + domain = iommu_get_dma_domain(dev); + cookie = domain->iova_cookie; + iovad = &cookie->iovad; + iova_off = iova_offset(iovad, phys); + + if (static_branch_unlikely(&iommu_deferred_attach_enabled) && + iommu_deferred_attach(dev, iommu_get_domain_for_dev(dev))) + return false; + + if (WARN_ON_ONCE(!size)) + return false; /* - * The IOMMU core code allocates the default DMA domain, which the - * underlying IOMMU driver needs to support via the dma-iommu layer. + * DMA_IOVA_USE_SWIOTLB is flag which is set by dma-iommu + * internals, make sure that caller didn't set it and/or + * didn't use this interface to map SIZE_MAX. */ - if (iommu_is_dma_domain(domain)) { - if (iommu_dma_init_domain(domain, dma_base, dma_limit, dev)) - goto out_err; - dev->dma_ops = &iommu_dma_ops; + if (WARN_ON_ONCE((u64)size & DMA_IOVA_USE_SWIOTLB)) + return false; + + addr = iommu_dma_alloc_iova(domain, + iova_align(iovad, size + iova_off), + dma_get_mask(dev), dev); + if (!addr) + return false; + + state->addr = addr + iova_off; + state->__size = size; + return true; +} +EXPORT_SYMBOL_GPL(dma_iova_try_alloc); + +/** + * dma_iova_free - Free an IOVA space + * @dev: Device to free the IOVA space for + * @state: IOVA state + * + * Undoes a successful dma_try_iova_alloc(). + * + * Note that all dma_iova_link() calls need to be undone first. For callers + * that never call dma_iova_unlink(), dma_iova_destroy() can be used instead + * which unlinks all ranges and frees the IOVA space in a single efficient + * operation. + */ +void dma_iova_free(struct device *dev, struct dma_iova_state *state) +{ + struct iommu_domain *domain = iommu_get_dma_domain(dev); + struct iommu_dma_cookie *cookie = domain->iova_cookie; + struct iova_domain *iovad = &cookie->iovad; + size_t iova_start_pad = iova_offset(iovad, state->addr); + size_t size = dma_iova_size(state); + + iommu_dma_free_iova(domain, state->addr - iova_start_pad, + iova_align(iovad, size + iova_start_pad), NULL); +} +EXPORT_SYMBOL_GPL(dma_iova_free); + +static int __dma_iova_link(struct device *dev, dma_addr_t addr, + phys_addr_t phys, size_t size, enum dma_data_direction dir, + unsigned long attrs) +{ + bool coherent = dev_is_dma_coherent(dev); + int prot = dma_info_to_prot(dir, coherent, attrs); + + if (!coherent && !(attrs & (DMA_ATTR_SKIP_CPU_SYNC | DMA_ATTR_MMIO))) + arch_sync_dma_for_device(phys, size, dir); + + return iommu_map_nosync(iommu_get_dma_domain(dev), addr, phys, size, + prot, GFP_ATOMIC); +} + +static int iommu_dma_iova_bounce_and_link(struct device *dev, dma_addr_t addr, + phys_addr_t phys, size_t bounce_len, + enum dma_data_direction dir, unsigned long attrs, + size_t iova_start_pad) +{ + struct iommu_domain *domain = iommu_get_dma_domain(dev); + struct iova_domain *iovad = &domain->iova_cookie->iovad; + phys_addr_t bounce_phys; + int error; + + bounce_phys = iommu_dma_map_swiotlb(dev, phys, bounce_len, dir, attrs); + if (bounce_phys == DMA_MAPPING_ERROR) + return -ENOMEM; + + error = __dma_iova_link(dev, addr - iova_start_pad, + bounce_phys - iova_start_pad, + iova_align(iovad, bounce_len), dir, attrs); + if (error) + swiotlb_tbl_unmap_single(dev, bounce_phys, bounce_len, dir, + attrs); + return error; +} + +static int iommu_dma_iova_link_swiotlb(struct device *dev, + struct dma_iova_state *state, phys_addr_t phys, size_t offset, + size_t size, enum dma_data_direction dir, unsigned long attrs) +{ + struct iommu_domain *domain = iommu_get_dma_domain(dev); + struct iommu_dma_cookie *cookie = domain->iova_cookie; + struct iova_domain *iovad = &cookie->iovad; + size_t iova_start_pad = iova_offset(iovad, phys); + size_t iova_end_pad = iova_offset(iovad, phys + size); + dma_addr_t addr = state->addr + offset; + size_t mapped = 0; + int error; + + if (iova_start_pad) { + size_t bounce_len = min(size, iovad->granule - iova_start_pad); + + error = iommu_dma_iova_bounce_and_link(dev, addr, phys, + bounce_len, dir, attrs, iova_start_pad); + if (error) + return error; + state->__size |= DMA_IOVA_USE_SWIOTLB; + + mapped += bounce_len; + size -= bounce_len; + if (!size) + return 0; } + size -= iova_end_pad; + error = __dma_iova_link(dev, addr + mapped, phys + mapped, size, dir, + attrs); + if (error) + goto out_unmap; + mapped += size; + + if (iova_end_pad) { + error = iommu_dma_iova_bounce_and_link(dev, addr + mapped, + phys + mapped, iova_end_pad, dir, attrs, 0); + if (error) + goto out_unmap; + state->__size |= DMA_IOVA_USE_SWIOTLB; + } + + return 0; + +out_unmap: + dma_iova_unlink(dev, state, 0, mapped, dir, attrs); + return error; +} + +/** + * dma_iova_link - Link a range of IOVA space + * @dev: DMA device + * @state: IOVA state + * @phys: physical address to link + * @offset: offset into the IOVA state to map into + * @size: size of the buffer + * @dir: DMA direction + * @attrs: attributes of mapping properties + * + * Link a range of IOVA space for the given IOVA state without IOTLB sync. + * This function is used to link multiple physical addresses in contiguous + * IOVA space without performing costly IOTLB sync. + * + * The caller is responsible to call to dma_iova_sync() to sync IOTLB at + * the end of linkage. + */ +int dma_iova_link(struct device *dev, struct dma_iova_state *state, + phys_addr_t phys, size_t offset, size_t size, + enum dma_data_direction dir, unsigned long attrs) +{ + struct iommu_domain *domain = iommu_get_dma_domain(dev); + struct iommu_dma_cookie *cookie = domain->iova_cookie; + struct iova_domain *iovad = &cookie->iovad; + size_t iova_start_pad = iova_offset(iovad, phys); + + if (WARN_ON_ONCE(iova_start_pad && offset > 0)) + return -EIO; + + if (dev_use_swiotlb(dev, size, dir) && + iova_unaligned(iovad, phys, size)) { + if (attrs & DMA_ATTR_MMIO) + return -EPERM; + + return iommu_dma_iova_link_swiotlb(dev, state, phys, offset, + size, dir, attrs); + } + + return __dma_iova_link(dev, state->addr + offset - iova_start_pad, + phys - iova_start_pad, + iova_align(iovad, size + iova_start_pad), dir, attrs); +} +EXPORT_SYMBOL_GPL(dma_iova_link); + +/** + * dma_iova_sync - Sync IOTLB + * @dev: DMA device + * @state: IOVA state + * @offset: offset into the IOVA state to sync + * @size: size of the buffer + * + * Sync IOTLB for the given IOVA state. This function should be called on + * the IOVA-contiguous range created by one ore more dma_iova_link() calls + * to sync the IOTLB. + */ +int dma_iova_sync(struct device *dev, struct dma_iova_state *state, + size_t offset, size_t size) +{ + struct iommu_domain *domain = iommu_get_dma_domain(dev); + struct iommu_dma_cookie *cookie = domain->iova_cookie; + struct iova_domain *iovad = &cookie->iovad; + dma_addr_t addr = state->addr + offset; + size_t iova_start_pad = iova_offset(iovad, addr); + + return iommu_sync_map(domain, addr - iova_start_pad, + iova_align(iovad, size + iova_start_pad)); +} +EXPORT_SYMBOL_GPL(dma_iova_sync); + +static void iommu_dma_iova_unlink_range_slow(struct device *dev, + dma_addr_t addr, size_t size, enum dma_data_direction dir, + unsigned long attrs) +{ + struct iommu_domain *domain = iommu_get_dma_domain(dev); + struct iommu_dma_cookie *cookie = domain->iova_cookie; + struct iova_domain *iovad = &cookie->iovad; + size_t iova_start_pad = iova_offset(iovad, addr); + dma_addr_t end = addr + size; + + do { + phys_addr_t phys; + size_t len; + + phys = iommu_iova_to_phys(domain, addr); + if (WARN_ON(!phys)) + /* Something very horrible happen here */ + return; + + len = min_t(size_t, + end - addr, iovad->granule - iova_start_pad); + + if (!dev_is_dma_coherent(dev) && + !(attrs & (DMA_ATTR_SKIP_CPU_SYNC | DMA_ATTR_MMIO))) + arch_sync_dma_for_cpu(phys, len, dir); + + swiotlb_tbl_unmap_single(dev, phys, len, dir, attrs); + + addr += len; + iova_start_pad = 0; + } while (addr < end); +} + +static void __iommu_dma_iova_unlink(struct device *dev, + struct dma_iova_state *state, size_t offset, size_t size, + enum dma_data_direction dir, unsigned long attrs, + bool free_iova) +{ + struct iommu_domain *domain = iommu_get_dma_domain(dev); + struct iommu_dma_cookie *cookie = domain->iova_cookie; + struct iova_domain *iovad = &cookie->iovad; + dma_addr_t addr = state->addr + offset; + size_t iova_start_pad = iova_offset(iovad, addr); + struct iommu_iotlb_gather iotlb_gather; + size_t unmapped; + + if ((state->__size & DMA_IOVA_USE_SWIOTLB) || + (!dev_is_dma_coherent(dev) && + !(attrs & (DMA_ATTR_SKIP_CPU_SYNC | DMA_ATTR_MMIO)))) + iommu_dma_iova_unlink_range_slow(dev, addr, size, dir, attrs); + + iommu_iotlb_gather_init(&iotlb_gather); + iotlb_gather.queued = free_iova && READ_ONCE(cookie->fq_domain); + + size = iova_align(iovad, size + iova_start_pad); + addr -= iova_start_pad; + unmapped = iommu_unmap_fast(domain, addr, size, &iotlb_gather); + WARN_ON(unmapped != size); + + if (!iotlb_gather.queued) + iommu_iotlb_sync(domain, &iotlb_gather); + if (free_iova) + iommu_dma_free_iova(domain, addr, size, &iotlb_gather); +} + +/** + * dma_iova_unlink - Unlink a range of IOVA space + * @dev: DMA device + * @state: IOVA state + * @offset: offset into the IOVA state to unlink + * @size: size of the buffer + * @dir: DMA direction + * @attrs: attributes of mapping properties + * + * Unlink a range of IOVA space for the given IOVA state. + */ +void dma_iova_unlink(struct device *dev, struct dma_iova_state *state, + size_t offset, size_t size, enum dma_data_direction dir, + unsigned long attrs) +{ + __iommu_dma_iova_unlink(dev, state, offset, size, dir, attrs, false); +} +EXPORT_SYMBOL_GPL(dma_iova_unlink); + +/** + * dma_iova_destroy - Finish a DMA mapping transaction + * @dev: DMA device + * @state: IOVA state + * @mapped_len: number of bytes to unmap + * @dir: DMA direction + * @attrs: attributes of mapping properties + * + * Unlink the IOVA range up to @mapped_len and free the entire IOVA space. The + * range of IOVA from dma_addr to @mapped_len must all be linked, and be the + * only linked IOVA in state. + */ +void dma_iova_destroy(struct device *dev, struct dma_iova_state *state, + size_t mapped_len, enum dma_data_direction dir, + unsigned long attrs) +{ + if (mapped_len) + __iommu_dma_iova_unlink(dev, state, 0, mapped_len, dir, attrs, + true); + else + /* + * We can be here if first call to dma_iova_link() failed and + * there is nothing to unlink, so let's be more clear. + */ + dma_iova_free(dev, state); +} +EXPORT_SYMBOL_GPL(dma_iova_destroy); + +void iommu_setup_dma_ops(struct device *dev) +{ + struct iommu_domain *domain = iommu_get_domain_for_dev(dev); + + if (dev_is_pci(dev)) + dev->iommu->pci_32bit_workaround = !iommu_dma_forcedac; + + dev->dma_iommu = iommu_is_dma_domain(domain); + if (dev->dma_iommu && iommu_dma_init_domain(domain, dev)) + goto out_err; + return; out_err: - pr_warn("Failed to set up IOMMU for device %s; retaining platform DMA ops\n", - dev_name(dev)); + pr_warn("Failed to set up IOMMU for device %s; retaining platform DMA ops\n", + dev_name(dev)); + dev->dma_iommu = false; +} + +static bool has_msi_cookie(const struct iommu_domain *domain) +{ + return domain && (domain->cookie_type == IOMMU_COOKIE_DMA_IOVA || + domain->cookie_type == IOMMU_COOKIE_DMA_MSI); +} + +static size_t cookie_msi_granule(const struct iommu_domain *domain) +{ + switch (domain->cookie_type) { + case IOMMU_COOKIE_DMA_IOVA: + return domain->iova_cookie->iovad.granule; + case IOMMU_COOKIE_DMA_MSI: + return PAGE_SIZE; + default: + BUG(); + } +} + +static struct list_head *cookie_msi_pages(const struct iommu_domain *domain) +{ + switch (domain->cookie_type) { + case IOMMU_COOKIE_DMA_IOVA: + return &domain->iova_cookie->msi_page_list; + case IOMMU_COOKIE_DMA_MSI: + return &domain->msi_cookie->msi_page_list; + default: + BUG(); + } } -EXPORT_SYMBOL_GPL(iommu_setup_dma_ops); static struct iommu_dma_msi_page *iommu_dma_get_msi_page(struct device *dev, phys_addr_t msi_addr, struct iommu_domain *domain) { - struct iommu_dma_cookie *cookie = domain->iova_cookie; + struct list_head *msi_page_list = cookie_msi_pages(domain); struct iommu_dma_msi_page *msi_page; dma_addr_t iova; int prot = IOMMU_WRITE | IOMMU_NOEXEC | IOMMU_MMIO; - size_t size = cookie_msi_granule(cookie); + size_t size = cookie_msi_granule(domain); msi_addr &= ~(phys_addr_t)(size - 1); - list_for_each_entry(msi_page, &cookie->msi_page_list, list) + list_for_each_entry(msi_page, msi_page_list, list) if (msi_page->phys == msi_addr) return msi_page; @@ -1632,70 +2173,35 @@ static struct iommu_dma_msi_page *iommu_dma_get_msi_page(struct device *dev, INIT_LIST_HEAD(&msi_page->list); msi_page->phys = msi_addr; msi_page->iova = iova; - list_add(&msi_page->list, &cookie->msi_page_list); + list_add(&msi_page->list, msi_page_list); return msi_page; out_free_iova: - iommu_dma_free_iova(cookie, iova, size, NULL); + iommu_dma_free_iova(domain, iova, size, NULL); out_free_page: kfree(msi_page); return NULL; } -/** - * iommu_dma_prepare_msi() - Map the MSI page in the IOMMU domain - * @desc: MSI descriptor, will store the MSI page - * @msi_addr: MSI target address to be mapped - * - * Return: 0 on success or negative error code if the mapping failed. - */ -int iommu_dma_prepare_msi(struct msi_desc *desc, phys_addr_t msi_addr) +int iommu_dma_sw_msi(struct iommu_domain *domain, struct msi_desc *desc, + phys_addr_t msi_addr) { struct device *dev = msi_desc_to_dev(desc); - struct iommu_domain *domain = iommu_get_domain_for_dev(dev); - struct iommu_dma_msi_page *msi_page; - static DEFINE_MUTEX(msi_prepare_lock); /* see below */ + const struct iommu_dma_msi_page *msi_page; - if (!domain || !domain->iova_cookie) { - desc->iommu_cookie = NULL; + if (!has_msi_cookie(domain)) { + msi_desc_set_iommu_msi_iova(desc, 0, 0); return 0; } - /* - * In fact the whole prepare operation should already be serialised by - * irq_domain_mutex further up the callchain, but that's pretty subtle - * on its own, so consider this locking as failsafe documentation... - */ - mutex_lock(&msi_prepare_lock); + iommu_group_mutex_assert(dev); msi_page = iommu_dma_get_msi_page(dev, msi_addr, domain); - mutex_unlock(&msi_prepare_lock); - - msi_desc_set_iommu_cookie(desc, msi_page); - if (!msi_page) return -ENOMEM; - return 0; -} -/** - * iommu_dma_compose_msi_msg() - Apply translation to an MSI message - * @desc: MSI descriptor prepared by iommu_dma_prepare_msi() - * @msg: MSI message containing target physical address - */ -void iommu_dma_compose_msi_msg(struct msi_desc *desc, struct msi_msg *msg) -{ - struct device *dev = msi_desc_to_dev(desc); - const struct iommu_domain *domain = iommu_get_domain_for_dev(dev); - const struct iommu_dma_msi_page *msi_page; - - msi_page = msi_desc_get_iommu_cookie(desc); - - if (!domain || !domain->iova_cookie || WARN_ON(!msi_page)) - return; - - msg->address_hi = upper_32_bits(msi_page->iova); - msg->address_lo &= cookie_msi_granule(domain->iova_cookie) - 1; - msg->address_lo += lower_32_bits(msi_page->iova); + msi_desc_set_iommu_msi_iova(desc, msi_page->iova, + ilog2(cookie_msi_granule(domain))); + return 0; } static int iommu_dma_init(void) |