/*- * SPDX-License-Identifier: BSD-2-Clause-FreeBSD * * Copyright (c) 2013 The FreeBSD Foundation * * This software was developed by Konstantin Belousov * under sponsorship from the FreeBSD Foundation. * * Redistribution and use in source and binary forms, with or without * modification, are permitted provided that the following conditions * are met: * 1. Redistributions of source code must retain the above copyright * notice, this list of conditions and the following disclaimer. * 2. Redistributions in binary form must reproduce the above copyright * notice, this list of conditions and the following disclaimer in the * documentation and/or other materials provided with the distribution. * * THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS'' AND * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE * ARE DISCLAIMED. IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF * SUCH DAMAGE. */ #include __FBSDID("$FreeBSD$"); #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include /* * busdma_iommu.c, the implementation of the busdma(9) interface using * IOMMU units from Intel VT-d. */ static bool iommu_bus_dma_is_dev_disabled(int domain, int bus, int slot, int func) { char str[128], *env; int default_bounce; bool ret; static const char bounce_str[] = "bounce"; static const char iommu_str[] = "iommu"; static const char dmar_str[] = "dmar"; /* compatibility */ default_bounce = 0; env = kern_getenv("hw.busdma.default"); if (env != NULL) { if (strcmp(env, bounce_str) == 0) default_bounce = 1; else if (strcmp(env, iommu_str) == 0 || strcmp(env, dmar_str) == 0) default_bounce = 0; freeenv(env); } snprintf(str, sizeof(str), "hw.busdma.pci%d.%d.%d.%d", domain, bus, slot, func); env = kern_getenv(str); if (env == NULL) return (default_bounce != 0); if (strcmp(env, bounce_str) == 0) ret = true; else if (strcmp(env, iommu_str) == 0 || strcmp(env, dmar_str) == 0) ret = false; else ret = default_bounce != 0; freeenv(env); return (ret); } /* * Given original device, find the requester ID that will be seen by * the IOMMU unit and used for page table lookup. PCI bridges may take * ownership of transactions from downstream devices, so it may not be * the same as the BSF of the target device. In those cases, all * devices downstream of the bridge must share a single mapping * domain, and must collectively be assigned to use either IOMMU or * bounce mapping. */ device_t iommu_get_requester(device_t dev, uint16_t *rid) { devclass_t pci_class; device_t l, pci, pcib, pcip, pcibp, requester; int cap_offset; uint16_t pcie_flags; bool bridge_is_pcie; pci_class = devclass_find("pci"); l = requester = dev; *rid = pci_get_rid(dev); /* * Walk the bridge hierarchy from the target device to the * host port to find the translating bridge nearest the IOMMU * unit. */ for (;;) { pci = device_get_parent(l); KASSERT(pci != NULL, ("iommu_get_requester(%s): NULL parent " "for %s", device_get_name(dev), device_get_name(l))); KASSERT(device_get_devclass(pci) == pci_class, ("iommu_get_requester(%s): non-pci parent %s for %s", device_get_name(dev), device_get_name(pci), device_get_name(l))); pcib = device_get_parent(pci); KASSERT(pcib != NULL, ("iommu_get_requester(%s): NULL bridge " "for %s", device_get_name(dev), device_get_name(pci))); /* * The parent of our "bridge" isn't another PCI bus, * so pcib isn't a PCI->PCI bridge but rather a host * port, and the requester ID won't be translated * further. */ pcip = device_get_parent(pcib); if (device_get_devclass(pcip) != pci_class) break; pcibp = device_get_parent(pcip); if (pci_find_cap(l, PCIY_EXPRESS, &cap_offset) == 0) { /* * Do not stop the loop even if the target * device is PCIe, because it is possible (but * unlikely) to have a PCI->PCIe bridge * somewhere in the hierarchy. */ l = pcib; } else { /* * Device is not PCIe, it cannot be seen as a * requester by IOMMU unit. Check whether the * bridge is PCIe. */ bridge_is_pcie = pci_find_cap(pcib, PCIY_EXPRESS, &cap_offset) == 0; requester = pcib; /* * Check for a buggy PCIe/PCI bridge that * doesn't report the express capability. If * the bridge above it is express but isn't a * PCI bridge, then we know pcib is actually a * PCIe/PCI bridge. */ if (!bridge_is_pcie && pci_find_cap(pcibp, PCIY_EXPRESS, &cap_offset) == 0) { pcie_flags = pci_read_config(pcibp, cap_offset + PCIER_FLAGS, 2); if ((pcie_flags & PCIEM_FLAGS_TYPE) != PCIEM_TYPE_PCI_BRIDGE) bridge_is_pcie = true; } if (bridge_is_pcie) { /* * The current device is not PCIe, but * the bridge above it is. This is a * PCIe->PCI bridge. Assume that the * requester ID will be the secondary * bus number with slot and function * set to zero. * * XXX: Doesn't handle the case where * the bridge is PCIe->PCI-X, and the * bridge will only take ownership of * requests in some cases. We should * provide context entries with the * same page tables for taken and * non-taken transactions. */ *rid = PCI_RID(pci_get_bus(l), 0, 0); l = pcibp; } else { /* * Neither the device nor the bridge * above it are PCIe. This is a * conventional PCI->PCI bridge, which * will use the bridge's BSF as the * requester ID. */ *rid = pci_get_rid(pcib); l = pcib; } } } return (requester); } struct iommu_ctx * iommu_instantiate_ctx(struct iommu_unit *unit, device_t dev, bool rmrr) { device_t requester; struct iommu_ctx *ctx; bool disabled; uint16_t rid; requester = iommu_get_requester(dev, &rid); /* * If the user requested the IOMMU disabled for the device, we * cannot disable the IOMMU unit, due to possibility of other * devices on the same IOMMU unit still requiring translation. * Instead provide the identity mapping for the device * context. */ disabled = iommu_bus_dma_is_dev_disabled(pci_get_domain(requester), pci_get_bus(requester), pci_get_slot(requester), pci_get_function(requester)); ctx = iommu_get_ctx(unit, requester, rid, disabled, rmrr); if (ctx == NULL) return (NULL); if (disabled) { /* * Keep the first reference on context, release the * later refs. */ IOMMU_LOCK(unit); if ((ctx->flags & IOMMU_CTX_DISABLED) == 0) { ctx->flags |= IOMMU_CTX_DISABLED; IOMMU_UNLOCK(unit); } else { iommu_free_ctx_locked(unit, ctx); } ctx = NULL; } return (ctx); } struct iommu_ctx * iommu_get_dev_ctx(device_t dev) { struct iommu_unit *unit; unit = iommu_find(dev, bootverbose); /* Not in scope of any IOMMU ? */ if (unit == NULL) return (NULL); if (!unit->dma_enabled) return (NULL); #if defined(__amd64__) || defined(__i386__) dmar_quirks_pre_use(unit); dmar_instantiate_rmrr_ctxs(unit); #endif return (iommu_instantiate_ctx(unit, dev, false)); } bus_dma_tag_t iommu_get_dma_tag(device_t dev, device_t child) { struct iommu_ctx *ctx; bus_dma_tag_t res; ctx = iommu_get_dev_ctx(child); if (ctx == NULL) return (NULL); res = (bus_dma_tag_t)ctx->tag; return (res); } bool bus_dma_iommu_set_buswide(device_t dev) { struct iommu_unit *unit; device_t parent; u_int busno, slot, func; parent = device_get_parent(dev); if (device_get_devclass(parent) != devclass_find("pci")) return (false); unit = iommu_find(dev, bootverbose); if (unit == NULL) return (false); busno = pci_get_bus(dev); slot = pci_get_slot(dev); func = pci_get_function(dev); if (slot != 0 || func != 0) { if (bootverbose) { device_printf(dev, "iommu%d pci%d:%d:%d requested buswide busdma\n", unit->unit, busno, slot, func); } return (false); } iommu_set_buswide_ctx(unit, busno); return (true); } void iommu_set_buswide_ctx(struct iommu_unit *unit, u_int busno) { MPASS(busno <= PCI_BUSMAX); IOMMU_LOCK(unit); unit->buswide_ctxs[busno / NBBY / sizeof(uint32_t)] |= 1 << (busno % (NBBY * sizeof(uint32_t))); IOMMU_UNLOCK(unit); } bool iommu_is_buswide_ctx(struct iommu_unit *unit, u_int busno) { MPASS(busno <= PCI_BUSMAX); return ((unit->buswide_ctxs[busno / NBBY / sizeof(uint32_t)] & (1U << (busno % (NBBY * sizeof(uint32_t))))) != 0); } static MALLOC_DEFINE(M_IOMMU_DMAMAP, "iommu_dmamap", "IOMMU DMA Map"); static void iommu_bus_schedule_dmamap(struct iommu_unit *unit, struct bus_dmamap_iommu *map); static int iommu_bus_dma_tag_create(bus_dma_tag_t parent, bus_size_t alignment, bus_addr_t boundary, bus_addr_t lowaddr, bus_addr_t highaddr, bus_dma_filter_t *filter, void *filterarg, bus_size_t maxsize, int nsegments, bus_size_t maxsegsz, int flags, bus_dma_lock_t *lockfunc, void *lockfuncarg, bus_dma_tag_t *dmat) { struct bus_dma_tag_iommu *newtag, *oldtag; int error; *dmat = NULL; error = common_bus_dma_tag_create(parent != NULL ? &((struct bus_dma_tag_iommu *)parent)->common : NULL, alignment, boundary, lowaddr, highaddr, filter, filterarg, maxsize, nsegments, maxsegsz, flags, lockfunc, lockfuncarg, sizeof(struct bus_dma_tag_iommu), (void **)&newtag); if (error != 0) goto out; oldtag = (struct bus_dma_tag_iommu *)parent; newtag->common.impl = &bus_dma_iommu_impl; newtag->ctx = oldtag->ctx; newtag->owner = oldtag->owner; *dmat = (bus_dma_tag_t)newtag; out: CTR4(KTR_BUSDMA, "%s returned tag %p tag flags 0x%x error %d", __func__, newtag, (newtag != NULL ? newtag->common.flags : 0), error); return (error); } static int iommu_bus_dma_tag_set_domain(bus_dma_tag_t dmat) { return (0); } static int iommu_bus_dma_tag_destroy(bus_dma_tag_t dmat1) { struct bus_dma_tag_iommu *dmat, *parent; struct bus_dma_tag_iommu *dmat_copy __unused; int error; error = 0; dmat_copy = dmat = (struct bus_dma_tag_iommu *)dmat1; if (dmat != NULL) { if (dmat->map_count != 0) { error = EBUSY; goto out; } while (dmat != NULL) { parent = (struct bus_dma_tag_iommu *)dmat->common.parent; if (atomic_fetchadd_int(&dmat->common.ref_count, -1) == 1) { if (dmat == dmat->ctx->tag) iommu_free_ctx(dmat->ctx); free(dmat->segments, M_IOMMU_DMAMAP); free(dmat, M_DEVBUF); dmat = parent; } else dmat = NULL; } } out: CTR3(KTR_BUSDMA, "%s tag %p error %d", __func__, dmat_copy, error); return (error); } static bool iommu_bus_dma_id_mapped(bus_dma_tag_t dmat, vm_paddr_t buf, bus_size_t buflen) { return (false); } static int iommu_bus_dmamap_create(bus_dma_tag_t dmat, int flags, bus_dmamap_t *mapp) { struct bus_dma_tag_iommu *tag; struct bus_dmamap_iommu *map; tag = (struct bus_dma_tag_iommu *)dmat; map = malloc_domainset(sizeof(*map), M_IOMMU_DMAMAP, DOMAINSET_PREF(tag->common.domain), M_NOWAIT | M_ZERO); if (map == NULL) { *mapp = NULL; return (ENOMEM); } if (tag->segments == NULL) { tag->segments = malloc_domainset(sizeof(bus_dma_segment_t) * tag->common.nsegments, M_IOMMU_DMAMAP, DOMAINSET_PREF(tag->common.domain), M_NOWAIT); if (tag->segments == NULL) { free(map, M_IOMMU_DMAMAP); *mapp = NULL; return (ENOMEM); } } IOMMU_DMAMAP_INIT(map); TAILQ_INIT(&map->map_entries); map->tag = tag; map->locked = true; map->cansleep = false; tag->map_count++; *mapp = (bus_dmamap_t)map; return (0); } static int iommu_bus_dmamap_destroy(bus_dma_tag_t dmat, bus_dmamap_t map1) { struct bus_dma_tag_iommu *tag; struct bus_dmamap_iommu *map; tag = (struct bus_dma_tag_iommu *)dmat; map = (struct bus_dmamap_iommu *)map1; if (map != NULL) { IOMMU_DMAMAP_LOCK(map); if (!TAILQ_EMPTY(&map->map_entries)) { IOMMU_DMAMAP_UNLOCK(map); return (EBUSY); } IOMMU_DMAMAP_DESTROY(map); free(map, M_IOMMU_DMAMAP); } tag->map_count--; return (0); } static int iommu_bus_dmamem_alloc(bus_dma_tag_t dmat, void** vaddr, int flags, bus_dmamap_t *mapp) { struct bus_dma_tag_iommu *tag; struct bus_dmamap_iommu *map; int error, mflags; vm_memattr_t attr; error = iommu_bus_dmamap_create(dmat, flags, mapp); if (error != 0) return (error); mflags = (flags & BUS_DMA_NOWAIT) != 0 ? M_NOWAIT : M_WAITOK; mflags |= (flags & BUS_DMA_ZERO) != 0 ? M_ZERO : 0; attr = (flags & BUS_DMA_NOCACHE) != 0 ? VM_MEMATTR_UNCACHEABLE : VM_MEMATTR_DEFAULT; tag = (struct bus_dma_tag_iommu *)dmat; map = (struct bus_dmamap_iommu *)*mapp; if (tag->common.maxsize < PAGE_SIZE && tag->common.alignment <= tag->common.maxsize && attr == VM_MEMATTR_DEFAULT) { *vaddr = malloc_domainset(tag->common.maxsize, M_DEVBUF, DOMAINSET_PREF(tag->common.domain), mflags); map->flags |= BUS_DMAMAP_IOMMU_MALLOC; } else { *vaddr = kmem_alloc_attr_domainset( DOMAINSET_PREF(tag->common.domain), tag->common.maxsize, mflags, 0ul, BUS_SPACE_MAXADDR, attr); map->flags |= BUS_DMAMAP_IOMMU_KMEM_ALLOC; } if (*vaddr == NULL) { iommu_bus_dmamap_destroy(dmat, *mapp); *mapp = NULL; return (ENOMEM); } return (0); } static void iommu_bus_dmamem_free(bus_dma_tag_t dmat, void *vaddr, bus_dmamap_t map1) { struct bus_dma_tag_iommu *tag; struct bus_dmamap_iommu *map; tag = (struct bus_dma_tag_iommu *)dmat; map = (struct bus_dmamap_iommu *)map1; if ((map->flags & BUS_DMAMAP_IOMMU_MALLOC) != 0) { free(vaddr, M_DEVBUF); map->flags &= ~BUS_DMAMAP_IOMMU_MALLOC; } else { KASSERT((map->flags & BUS_DMAMAP_IOMMU_KMEM_ALLOC) != 0, ("iommu_bus_dmamem_free for non alloced map %p", map)); kmem_free(vaddr, tag->common.maxsize); map->flags &= ~BUS_DMAMAP_IOMMU_KMEM_ALLOC; } iommu_bus_dmamap_destroy(dmat, map1); } static int iommu_bus_dmamap_load_something1(struct bus_dma_tag_iommu *tag, struct bus_dmamap_iommu *map, vm_page_t *ma, int offset, bus_size_t buflen, int flags, bus_dma_segment_t *segs, int *segp, struct iommu_map_entries_tailq *entries) { struct iommu_ctx *ctx; struct iommu_domain *domain; struct iommu_map_entry *entry; bus_size_t buflen1; int error, e_flags, idx, gas_flags, seg; KASSERT(offset < IOMMU_PAGE_SIZE, ("offset %d", offset)); if (segs == NULL) segs = tag->segments; ctx = tag->ctx; domain = ctx->domain; e_flags = IOMMU_MAP_ENTRY_READ | ((flags & BUS_DMA_NOWRITE) == 0 ? IOMMU_MAP_ENTRY_WRITE : 0); seg = *segp; error = 0; idx = 0; while (buflen > 0) { seg++; if (seg >= tag->common.nsegments) { error = EFBIG; break; } buflen1 = buflen > tag->common.maxsegsz ? tag->common.maxsegsz : buflen; /* * (Too) optimistically allow split if there are more * then one segments left. */ gas_flags = map->cansleep ? IOMMU_MF_CANWAIT : 0; if (seg + 1 < tag->common.nsegments) gas_flags |= IOMMU_MF_CANSPLIT; error = iommu_gas_map(domain, &tag->common, buflen1, offset, e_flags, gas_flags, ma + idx, &entry); if (error != 0) break; /* Update buflen1 in case buffer split. */ if (buflen1 > entry->end - entry->start - offset) buflen1 = entry->end - entry->start - offset; KASSERT(vm_addr_align_ok(entry->start + offset, tag->common.alignment), ("alignment failed: ctx %p start 0x%jx offset %x " "align 0x%jx", ctx, (uintmax_t)entry->start, offset, (uintmax_t)tag->common.alignment)); KASSERT(entry->end <= tag->common.lowaddr || entry->start >= tag->common.highaddr, ("entry placement failed: ctx %p start 0x%jx end 0x%jx " "lowaddr 0x%jx highaddr 0x%jx", ctx, (uintmax_t)entry->start, (uintmax_t)entry->end, (uintmax_t)tag->common.lowaddr, (uintmax_t)tag->common.highaddr)); KASSERT(vm_addr_bound_ok(entry->start + offset, buflen1, tag->common.boundary), ("boundary failed: ctx %p start 0x%jx end 0x%jx " "boundary 0x%jx", ctx, (uintmax_t)entry->start, (uintmax_t)entry->end, (uintmax_t)tag->common.boundary)); KASSERT(buflen1 <= tag->common.maxsegsz, ("segment too large: ctx %p start 0x%jx end 0x%jx " "buflen1 0x%jx maxsegsz 0x%jx", ctx, (uintmax_t)entry->start, (uintmax_t)entry->end, (uintmax_t)buflen1, (uintmax_t)tag->common.maxsegsz)); KASSERT((entry->flags & IOMMU_MAP_ENTRY_MAP) != 0, ("entry %p missing IOMMU_MAP_ENTRY_MAP", entry)); TAILQ_INSERT_TAIL(entries, entry, dmamap_link); segs[seg].ds_addr = entry->start + offset; segs[seg].ds_len = buflen1; idx += OFF_TO_IDX(offset + buflen1); offset += buflen1; offset &= IOMMU_PAGE_MASK; buflen -= buflen1; } if (error == 0) *segp = seg; return (error); } static int iommu_bus_dmamap_load_something(struct bus_dma_tag_iommu *tag, struct bus_dmamap_iommu *map, vm_page_t *ma, int offset, bus_size_t buflen, int flags, bus_dma_segment_t *segs, int *segp) { struct iommu_ctx *ctx; struct iommu_domain *domain; struct iommu_map_entries_tailq entries; int error; ctx = tag->ctx; domain = ctx->domain; atomic_add_long(&ctx->loads, 1); TAILQ_INIT(&entries); error = iommu_bus_dmamap_load_something1(tag, map, ma, offset, buflen, flags, segs, segp, &entries); if (error == 0) { IOMMU_DMAMAP_LOCK(map); TAILQ_CONCAT(&map->map_entries, &entries, dmamap_link); IOMMU_DMAMAP_UNLOCK(map); } else if (!TAILQ_EMPTY(&entries)) { /* * The busdma interface does not allow us to report * partial buffer load, so unfortunately we have to * revert all work done. */ IOMMU_DOMAIN_LOCK(domain); TAILQ_CONCAT(&domain->unload_entries, &entries, dmamap_link); IOMMU_DOMAIN_UNLOCK(domain); taskqueue_enqueue(domain->iommu->delayed_taskqueue, &domain->unload_task); } if (error == ENOMEM && (flags & BUS_DMA_NOWAIT) == 0 && !map->cansleep) error = EINPROGRESS; if (error == EINPROGRESS) iommu_bus_schedule_dmamap(domain->iommu, map); return (error); } static int iommu_bus_dmamap_load_ma(bus_dma_tag_t dmat, bus_dmamap_t map1, struct vm_page **ma, bus_size_t tlen, int ma_offs, int flags, bus_dma_segment_t *segs, int *segp) { struct bus_dma_tag_iommu *tag; struct bus_dmamap_iommu *map; tag = (struct bus_dma_tag_iommu *)dmat; map = (struct bus_dmamap_iommu *)map1; return (iommu_bus_dmamap_load_something(tag, map, ma, ma_offs, tlen, flags, segs, segp)); } static int iommu_bus_dmamap_load_phys(bus_dma_tag_t dmat, bus_dmamap_t map1, vm_paddr_t buf, bus_size_t buflen, int flags, bus_dma_segment_t *segs, int *segp) { struct bus_dma_tag_iommu *tag; struct bus_dmamap_iommu *map; vm_page_t *ma, fma; vm_paddr_t pstart, pend, paddr; int error, i, ma_cnt, mflags, offset; tag = (struct bus_dma_tag_iommu *)dmat; map = (struct bus_dmamap_iommu *)map1; pstart = trunc_page(buf); pend = round_page(buf + buflen); offset = buf & PAGE_MASK; ma_cnt = OFF_TO_IDX(pend - pstart); mflags = map->cansleep ? M_WAITOK : M_NOWAIT; ma = malloc(sizeof(vm_page_t) * ma_cnt, M_DEVBUF, mflags); if (ma == NULL) return (ENOMEM); fma = NULL; for (i = 0; i < ma_cnt; i++) { paddr = pstart + ptoa(i); ma[i] = PHYS_TO_VM_PAGE(paddr); if (ma[i] == NULL || VM_PAGE_TO_PHYS(ma[i]) != paddr) { /* * If PHYS_TO_VM_PAGE() returned NULL or the * vm_page was not initialized we'll use a * fake page. */ if (fma == NULL) { fma = malloc(sizeof(struct vm_page) * ma_cnt, M_DEVBUF, M_ZERO | mflags); if (fma == NULL) { free(ma, M_DEVBUF); return (ENOMEM); } } vm_page_initfake(&fma[i], pstart + ptoa(i), VM_MEMATTR_DEFAULT); ma[i] = &fma[i]; } } error = iommu_bus_dmamap_load_something(tag, map, ma, offset, buflen, flags, segs, segp); free(fma, M_DEVBUF); free(ma, M_DEVBUF); return (error); } static int iommu_bus_dmamap_load_buffer(bus_dma_tag_t dmat, bus_dmamap_t map1, void *buf, bus_size_t buflen, pmap_t pmap, int flags, bus_dma_segment_t *segs, int *segp) { struct bus_dma_tag_iommu *tag; struct bus_dmamap_iommu *map; vm_page_t *ma, fma; vm_paddr_t pstart, pend, paddr; int error, i, ma_cnt, mflags, offset; tag = (struct bus_dma_tag_iommu *)dmat; map = (struct bus_dmamap_iommu *)map1; pstart = trunc_page((vm_offset_t)buf); pend = round_page((vm_offset_t)buf + buflen); offset = (vm_offset_t)buf & PAGE_MASK; ma_cnt = OFF_TO_IDX(pend - pstart); mflags = map->cansleep ? M_WAITOK : M_NOWAIT; ma = malloc(sizeof(vm_page_t) * ma_cnt, M_DEVBUF, mflags); if (ma == NULL) return (ENOMEM); fma = NULL; for (i = 0; i < ma_cnt; i++, pstart += PAGE_SIZE) { if (pmap == kernel_pmap) paddr = pmap_kextract(pstart); else paddr = pmap_extract(pmap, pstart); ma[i] = PHYS_TO_VM_PAGE(paddr); if (ma[i] == NULL || VM_PAGE_TO_PHYS(ma[i]) != paddr) { /* * If PHYS_TO_VM_PAGE() returned NULL or the * vm_page was not initialized we'll use a * fake page. */ if (fma == NULL) { fma = malloc(sizeof(struct vm_page) * ma_cnt, M_DEVBUF, M_ZERO | mflags); if (fma == NULL) { free(ma, M_DEVBUF); return (ENOMEM); } } vm_page_initfake(&fma[i], paddr, VM_MEMATTR_DEFAULT); ma[i] = &fma[i]; } } error = iommu_bus_dmamap_load_something(tag, map, ma, offset, buflen, flags, segs, segp); free(ma, M_DEVBUF); free(fma, M_DEVBUF); return (error); } static void iommu_bus_dmamap_waitok(bus_dma_tag_t dmat, bus_dmamap_t map1, struct memdesc *mem, bus_dmamap_callback_t *callback, void *callback_arg) { struct bus_dmamap_iommu *map; if (map1 == NULL) return; map = (struct bus_dmamap_iommu *)map1; map->mem = *mem; map->tag = (struct bus_dma_tag_iommu *)dmat; map->callback = callback; map->callback_arg = callback_arg; } static bus_dma_segment_t * iommu_bus_dmamap_complete(bus_dma_tag_t dmat, bus_dmamap_t map1, bus_dma_segment_t *segs, int nsegs, int error) { struct bus_dma_tag_iommu *tag; struct bus_dmamap_iommu *map; tag = (struct bus_dma_tag_iommu *)dmat; map = (struct bus_dmamap_iommu *)map1; if (!map->locked) { KASSERT(map->cansleep, ("map not locked and not sleepable context %p", map)); /* * We are called from the delayed context. Relock the * driver. */ (tag->common.lockfunc)(tag->common.lockfuncarg, BUS_DMA_LOCK); map->locked = true; } if (segs == NULL) segs = tag->segments; return (segs); } /* * The limitations of busdma KPI forces the iommu to perform the actual * unload, consisting of the unmapping of the map entries page tables, * from the delayed context on i386, since page table page mapping * might require a sleep to be successfull. The unfortunate * consequence is that the DMA requests can be served some time after * the bus_dmamap_unload() call returned. * * On amd64, we assume that sf allocation cannot fail. */ static void iommu_bus_dmamap_unload(bus_dma_tag_t dmat, bus_dmamap_t map1) { struct bus_dma_tag_iommu *tag; struct bus_dmamap_iommu *map; struct iommu_ctx *ctx; struct iommu_domain *domain; struct iommu_map_entries_tailq entries; tag = (struct bus_dma_tag_iommu *)dmat; map = (struct bus_dmamap_iommu *)map1; ctx = tag->ctx; domain = ctx->domain; atomic_add_long(&ctx->unloads, 1); TAILQ_INIT(&entries); IOMMU_DMAMAP_LOCK(map); TAILQ_CONCAT(&entries, &map->map_entries, dmamap_link); IOMMU_DMAMAP_UNLOCK(map); #if defined(IOMMU_DOMAIN_UNLOAD_SLEEP) IOMMU_DOMAIN_LOCK(domain); TAILQ_CONCAT(&domain->unload_entries, &entries, dmamap_link); IOMMU_DOMAIN_UNLOCK(domain); taskqueue_enqueue(domain->iommu->delayed_taskqueue, &domain->unload_task); #else THREAD_NO_SLEEPING(); iommu_domain_unload(domain, &entries, false); THREAD_SLEEPING_OK(); KASSERT(TAILQ_EMPTY(&entries), ("lazy iommu_ctx_unload %p", ctx)); #endif } static void iommu_bus_dmamap_sync(bus_dma_tag_t dmat, bus_dmamap_t map1, bus_dmasync_op_t op) { struct bus_dmamap_iommu *map __unused; map = (struct bus_dmamap_iommu *)map1; kmsan_bus_dmamap_sync(&map->kmsan_mem, op); } #ifdef KMSAN static void iommu_bus_dmamap_load_kmsan(bus_dmamap_t map1, struct memdesc *mem) { struct bus_dmamap_iommu *map; map = (struct bus_dmamap_iommu *)map1; if (map == NULL) return; memcpy(&map->kmsan_mem, mem, sizeof(struct memdesc)); } #endif struct bus_dma_impl bus_dma_iommu_impl = { .tag_create = iommu_bus_dma_tag_create, .tag_destroy = iommu_bus_dma_tag_destroy, .tag_set_domain = iommu_bus_dma_tag_set_domain, .id_mapped = iommu_bus_dma_id_mapped, .map_create = iommu_bus_dmamap_create, .map_destroy = iommu_bus_dmamap_destroy, .mem_alloc = iommu_bus_dmamem_alloc, .mem_free = iommu_bus_dmamem_free, .load_phys = iommu_bus_dmamap_load_phys, .load_buffer = iommu_bus_dmamap_load_buffer, .load_ma = iommu_bus_dmamap_load_ma, .map_waitok = iommu_bus_dmamap_waitok, .map_complete = iommu_bus_dmamap_complete, .map_unload = iommu_bus_dmamap_unload, .map_sync = iommu_bus_dmamap_sync, #ifdef KMSAN .load_kmsan = iommu_bus_dmamap_load_kmsan, #endif }; static void iommu_bus_task_dmamap(void *arg, int pending) { struct bus_dma_tag_iommu *tag; struct bus_dmamap_iommu *map; struct iommu_unit *unit; unit = arg; IOMMU_LOCK(unit); while ((map = TAILQ_FIRST(&unit->delayed_maps)) != NULL) { TAILQ_REMOVE(&unit->delayed_maps, map, delay_link); IOMMU_UNLOCK(unit); tag = map->tag; map->cansleep = true; map->locked = false; bus_dmamap_load_mem((bus_dma_tag_t)tag, (bus_dmamap_t)map, &map->mem, map->callback, map->callback_arg, BUS_DMA_WAITOK); map->cansleep = false; if (map->locked) { (tag->common.lockfunc)(tag->common.lockfuncarg, BUS_DMA_UNLOCK); } else map->locked = true; map->cansleep = false; IOMMU_LOCK(unit); } IOMMU_UNLOCK(unit); } static void iommu_bus_schedule_dmamap(struct iommu_unit *unit, struct bus_dmamap_iommu *map) { map->locked = false; IOMMU_LOCK(unit); TAILQ_INSERT_TAIL(&unit->delayed_maps, map, delay_link); IOMMU_UNLOCK(unit); taskqueue_enqueue(unit->delayed_taskqueue, &unit->dmamap_load_task); } int iommu_init_busdma(struct iommu_unit *unit) { int error; unit->dma_enabled = 1; error = TUNABLE_INT_FETCH("hw.iommu.dma", &unit->dma_enabled); if (error == 0) /* compatibility */ TUNABLE_INT_FETCH("hw.dmar.dma", &unit->dma_enabled); TAILQ_INIT(&unit->delayed_maps); TASK_INIT(&unit->dmamap_load_task, 0, iommu_bus_task_dmamap, unit); unit->delayed_taskqueue = taskqueue_create("iommu", M_WAITOK, taskqueue_thread_enqueue, &unit->delayed_taskqueue); taskqueue_start_threads(&unit->delayed_taskqueue, 1, PI_DISK, "iommu%d busdma taskq", unit->unit); return (0); } void iommu_fini_busdma(struct iommu_unit *unit) { if (unit->delayed_taskqueue == NULL) return; taskqueue_drain(unit->delayed_taskqueue, &unit->dmamap_load_task); taskqueue_free(unit->delayed_taskqueue); unit->delayed_taskqueue = NULL; } int bus_dma_iommu_load_ident(bus_dma_tag_t dmat, bus_dmamap_t map1, vm_paddr_t start, vm_size_t length, int flags) { struct bus_dma_tag_common *tc; struct bus_dma_tag_iommu *tag; struct bus_dmamap_iommu *map; struct iommu_ctx *ctx; struct iommu_domain *domain; struct iommu_map_entry *entry; vm_page_t *ma; vm_size_t i; int error; bool waitok; MPASS((start & PAGE_MASK) == 0); MPASS((length & PAGE_MASK) == 0); MPASS(length > 0); MPASS(start + length >= start); MPASS((flags & ~(BUS_DMA_NOWAIT | BUS_DMA_NOWRITE)) == 0); tc = (struct bus_dma_tag_common *)dmat; if (tc->impl != &bus_dma_iommu_impl) return (0); tag = (struct bus_dma_tag_iommu *)dmat; ctx = tag->ctx; domain = ctx->domain; map = (struct bus_dmamap_iommu *)map1; waitok = (flags & BUS_DMA_NOWAIT) != 0; entry = iommu_gas_alloc_entry(domain, waitok ? 0 : IOMMU_PGF_WAITOK); if (entry == NULL) return (ENOMEM); entry->start = start; entry->end = start + length; ma = malloc(sizeof(vm_page_t) * atop(length), M_TEMP, waitok ? M_WAITOK : M_NOWAIT); if (ma == NULL) { iommu_gas_free_entry(entry); return (ENOMEM); } for (i = 0; i < atop(length); i++) { ma[i] = vm_page_getfake(entry->start + PAGE_SIZE * i, VM_MEMATTR_DEFAULT); } error = iommu_gas_map_region(domain, entry, IOMMU_MAP_ENTRY_READ | ((flags & BUS_DMA_NOWRITE) ? 0 : IOMMU_MAP_ENTRY_WRITE) | IOMMU_MAP_ENTRY_MAP, waitok ? IOMMU_MF_CANWAIT : 0, ma); if (error == 0) { IOMMU_DMAMAP_LOCK(map); TAILQ_INSERT_TAIL(&map->map_entries, entry, dmamap_link); IOMMU_DMAMAP_UNLOCK(map); } else { iommu_gas_free_entry(entry); } for (i = 0; i < atop(length); i++) vm_page_putfake(ma[i]); free(ma, M_TEMP); return (error); } static void iommu_domain_unload_task(void *arg, int pending) { struct iommu_domain *domain; struct iommu_map_entries_tailq entries; domain = arg; TAILQ_INIT(&entries); for (;;) { IOMMU_DOMAIN_LOCK(domain); TAILQ_SWAP(&domain->unload_entries, &entries, iommu_map_entry, dmamap_link); IOMMU_DOMAIN_UNLOCK(domain); if (TAILQ_EMPTY(&entries)) break; iommu_domain_unload(domain, &entries, true); } } void iommu_domain_init(struct iommu_unit *unit, struct iommu_domain *domain, const struct iommu_domain_map_ops *ops) { domain->ops = ops; domain->iommu = unit; TASK_INIT(&domain->unload_task, 0, iommu_domain_unload_task, domain); RB_INIT(&domain->rb_root); TAILQ_INIT(&domain->unload_entries); mtx_init(&domain->lock, "iodom", NULL, MTX_DEF); } void iommu_domain_fini(struct iommu_domain *domain) { mtx_destroy(&domain->lock); }