/* $NetBSD: ttm_bo_vm.c,v 1.28 2024/06/23 00:49:31 riastradh Exp $ */ /*- * Copyright (c) 2014 The NetBSD Foundation, Inc. * All rights reserved. * * This code is derived from software contributed to The NetBSD Foundation * by Taylor R. Campbell. * * 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 NETBSD FOUNDATION, INC. 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 FOUNDATION 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. */ /************************************************************************** * * Copyright (c) 2006-2009 VMware, Inc., Palo Alto, CA., USA * All Rights Reserved. * * Permission is hereby granted, free of charge, to any person obtaining a * copy of this software and associated documentation files (the * "Software"), to deal in the Software without restriction, including * without limitation the rights to use, copy, modify, merge, publish, * distribute, sub license, and/or sell copies of the Software, and to * permit persons to whom the Software is furnished to do so, subject to * the following conditions: * * The above copyright notice and this permission notice (including the * next paragraph) shall be included in all copies or substantial portions * of the Software. * * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY, * FITNESS FOR A PARTICULAR PURPOSE AND NON-INFRINGEMENT. IN NO EVENT SHALL * THE COPYRIGHT HOLDERS, AUTHORS AND/OR ITS SUPPLIERS BE LIABLE FOR ANY CLAIM, * DAMAGES OR OTHER LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR * OTHERWISE, ARISING FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE * USE OR OTHER DEALINGS IN THE SOFTWARE. * **************************************************************************/ /* * Authors: Thomas Hellstrom */ #include __KERNEL_RCSID(0, "$NetBSD: ttm_bo_vm.c,v 1.28 2024/06/23 00:49:31 riastradh Exp $"); #include #include #include #include #include #include #include static int ttm_bo_uvm_lookup(struct ttm_bo_device *, unsigned long, unsigned long, struct ttm_buffer_object **); void ttm_bo_uvm_reference(struct uvm_object *uobj) { struct ttm_buffer_object *const bo = container_of(uobj, struct ttm_buffer_object, uvmobj); (void)ttm_bo_get(bo); } void ttm_bo_uvm_detach(struct uvm_object *uobj) { struct ttm_buffer_object *bo = container_of(uobj, struct ttm_buffer_object, uvmobj); ttm_bo_put(bo); } static int ttm_bo_vm_fault_idle(struct ttm_buffer_object *bo, struct uvm_faultinfo *vmf) { int err, ret = 0; if (__predict_true(!bo->moving)) goto out_unlock; /* * Quick non-stalling check for idle. */ if (dma_fence_is_signaled(bo->moving)) goto out_clear; /* * If possible, avoid waiting for GPU with mmap_sem * held. */ if (1) { /* always retriable in NetBSD */ ret = ERESTART; ttm_bo_get(bo); uvmfault_unlockall(vmf, vmf->entry->aref.ar_amap, NULL); (void) dma_fence_wait(bo->moving, true); dma_resv_unlock(bo->base.resv); ttm_bo_put(bo); goto out_unlock; } /* * Ordinary wait. */ err = dma_fence_wait(bo->moving, true); if (__predict_false(err != 0)) { ret = (err != -ERESTARTSYS) ? EINVAL/*SIGBUS*/ : 0/*retry access in userland*/; goto out_unlock; } out_clear: dma_fence_put(bo->moving); bo->moving = NULL; out_unlock: return ret; } static int ttm_bo_vm_reserve(struct ttm_buffer_object *bo, struct uvm_faultinfo *vmf) { /* * Work around locking order reversal in fault / nopfn * between mmap_sem and bo_reserve: Perform a trylock operation * for reserve, and if it fails, retry the fault after waiting * for the buffer to become unreserved. */ if (__predict_false(!dma_resv_trylock(bo->base.resv))) { ttm_bo_get(bo); uvmfault_unlockall(vmf, vmf->entry->aref.ar_amap, NULL); if (!dma_resv_lock_interruptible(bo->base.resv, NULL)) dma_resv_unlock(bo->base.resv); ttm_bo_put(bo); return ERESTART; } return 0; } static int ttm_bo_uvm_fault_reserved(struct uvm_faultinfo *vmf, vaddr_t vaddr, struct vm_page **pps, int npages, int centeridx, vm_prot_t access_type, int flags) { struct uvm_object *const uobj = vmf->entry->object.uvm_obj; struct ttm_buffer_object *const bo = container_of(uobj, struct ttm_buffer_object, uvmobj); struct ttm_bo_device *const bdev = bo->bdev; struct ttm_mem_type_manager *man = &bdev->man[bo->mem.mem_type]; union { bus_addr_t base; struct ttm_tt *ttm; } u; size_t size __diagused; voff_t uoffset; /* offset in bytes into bo */ unsigned startpage; /* offset in pages into bo */ unsigned i; vm_prot_t vm_prot = vmf->entry->protection; /* VM_PROT_* */ pgprot_t prot = vm_prot; /* VM_PROT_* | PMAP_* cacheability flags */ int err, ret; /* * Refuse to fault imported pages. This should be handled * (if at all) by redirecting mmap to the exporter. */ if (bo->ttm && (bo->ttm->page_flags & TTM_PAGE_FLAG_SG)) return EINVAL; /* SIGBUS */ if (bdev->driver->fault_reserve_notify) { struct dma_fence *moving = dma_fence_get(bo->moving); err = bdev->driver->fault_reserve_notify(bo); switch (err) { case 0: break; case -EBUSY: case -ERESTARTSYS: return 0; /* retry access in userland */ default: return EINVAL; /* SIGBUS */ } if (bo->moving != moving) { spin_lock(&ttm_bo_glob.lru_lock); ttm_bo_move_to_lru_tail(bo, NULL); spin_unlock(&ttm_bo_glob.lru_lock); } dma_fence_put(moving); } /* * Wait for buffer data in transit, due to a pipelined * move. */ ret = ttm_bo_vm_fault_idle(bo, vmf); if (__predict_false(ret != 0)) return ret; err = ttm_mem_io_lock(man, true); if (__predict_false(err != 0)) return 0; /* retry access in userland */ err = ttm_mem_io_reserve_vm(bo); if (__predict_false(err != 0)) { ret = EINVAL; /* SIGBUS */ goto out_io_unlock; } prot = ttm_io_prot(bo->mem.placement, prot); if (!bo->mem.bus.is_iomem) { struct ttm_operation_ctx ctx = { .interruptible = false, .no_wait_gpu = false, .flags = TTM_OPT_FLAG_FORCE_ALLOC }; u.ttm = bo->ttm; size = (size_t)bo->ttm->num_pages << PAGE_SHIFT; if (ttm_tt_populate(bo->ttm, &ctx)) { ret = ENOMEM; goto out_io_unlock; } } else { u.base = (bo->mem.bus.base + bo->mem.bus.offset); size = bo->mem.bus.size; } KASSERT(vmf->entry->start <= vaddr); KASSERT((vmf->entry->offset & (PAGE_SIZE - 1)) == 0); KASSERT(vmf->entry->offset <= size); KASSERT((vaddr - vmf->entry->start) <= (size - vmf->entry->offset)); KASSERTMSG(((size_t)npages << PAGE_SHIFT <= ((size - vmf->entry->offset) - (vaddr - vmf->entry->start))), "vaddr=%jx npages=%d bo=%p is_iomem=%d size=%zu" " start=%jx offset=%jx", (uintmax_t)vaddr, npages, bo, (int)bo->mem.bus.is_iomem, size, (uintmax_t)vmf->entry->start, (uintmax_t)vmf->entry->offset); uoffset = (vmf->entry->offset + (vaddr - vmf->entry->start)); startpage = (uoffset >> PAGE_SHIFT); for (i = 0; i < npages; i++) { paddr_t paddr; if ((flags & PGO_ALLPAGES) == 0 && i != centeridx) continue; if (pps[i] == PGO_DONTCARE) continue; if (!bo->mem.bus.is_iomem) { paddr = page_to_phys(u.ttm->pages[startpage + i]); } else if (bdev->driver->io_mem_pfn) { paddr = (paddr_t)(*bdev->driver->io_mem_pfn)(bo, startpage + i) << PAGE_SHIFT; } else { const paddr_t cookie = bus_space_mmap(bdev->memt, u.base, (off_t)(startpage + i) << PAGE_SHIFT, vm_prot, 0); paddr = pmap_phys_address(cookie); #if 0 /* XXX Why no PMAP_* flags added here? */ mmapflags = pmap_mmap_flags(cookie); #endif } ret = pmap_enter(vmf->orig_map->pmap, vaddr + i*PAGE_SIZE, paddr, vm_prot, PMAP_CANFAIL | prot); if (ret) { /* * XXX Continue with ret=0 if i != centeridx, * so we don't fail if only readahead pages * fail? */ KASSERT(ret != ERESTART); break; } } pmap_update(vmf->orig_map->pmap); ret = 0; /* retry access in userland */ out_io_unlock: ttm_mem_io_unlock(man); KASSERT(ret != ERESTART); return ret; } int ttm_bo_uvm_fault(struct uvm_faultinfo *vmf, vaddr_t vaddr, struct vm_page **pps, int npages, int centeridx, vm_prot_t access_type, int flags) { struct uvm_object *const uobj = vmf->entry->object.uvm_obj; struct ttm_buffer_object *const bo = container_of(uobj, struct ttm_buffer_object, uvmobj); int ret; /* Thanks, uvm, but we don't need this lock. */ rw_exit(uobj->vmobjlock); /* Copy-on-write mappings make no sense for the graphics aperture. */ if (UVM_ET_ISCOPYONWRITE(vmf->entry)) { ret = EINVAL; /* SIGBUS */ goto out; } ret = ttm_bo_vm_reserve(bo, vmf); if (ret) { /* ttm_bo_vm_reserve already unlocked on ERESTART */ KASSERTMSG(ret == ERESTART, "ret=%d", ret); return ret; } ret = ttm_bo_uvm_fault_reserved(vmf, vaddr, pps, npages, centeridx, access_type, flags); if (ret == ERESTART) /* already unlocked on ERESTART */ return ret; dma_resv_unlock(bo->base.resv); out: uvmfault_unlockall(vmf, vmf->entry->aref.ar_amap, NULL); return ret; } int ttm_bo_mmap_object(struct ttm_bo_device *bdev, off_t offset, size_t size, vm_prot_t prot, struct uvm_object **uobjp, voff_t *uoffsetp, struct file *file) { const unsigned long startpage = (offset >> PAGE_SHIFT); const unsigned long npages = (size >> PAGE_SHIFT); struct ttm_buffer_object *bo; int ret; KASSERT(0 == (offset & (PAGE_SIZE - 1))); KASSERT(0 == (size & (PAGE_SIZE - 1))); ret = ttm_bo_uvm_lookup(bdev, startpage, npages, &bo); if (ret) goto fail0; KASSERTMSG((drm_vma_node_start(&bo->base.vma_node) <= startpage), "mapping npages=0x%jx @ pfn=0x%jx" " from vma npages=0x%jx @ pfn=0x%jx", (uintmax_t)npages, (uintmax_t)startpage, (uintmax_t)drm_vma_node_size(&bo->base.vma_node), (uintmax_t)drm_vma_node_start(&bo->base.vma_node)); KASSERTMSG((npages <= drm_vma_node_size(&bo->base.vma_node)), "mapping npages=0x%jx @ pfn=0x%jx" " from vma npages=0x%jx @ pfn=0x%jx", (uintmax_t)npages, (uintmax_t)startpage, (uintmax_t)drm_vma_node_size(&bo->base.vma_node), (uintmax_t)drm_vma_node_start(&bo->base.vma_node)); KASSERTMSG(((startpage - drm_vma_node_start(&bo->base.vma_node)) <= (drm_vma_node_size(&bo->base.vma_node) - npages)), "mapping npages=0x%jx @ pfn=0x%jx" " from vma npages=0x%jx @ pfn=0x%jx", (uintmax_t)npages, (uintmax_t)startpage, (uintmax_t)drm_vma_node_size(&bo->base.vma_node), (uintmax_t)drm_vma_node_start(&bo->base.vma_node)); /* XXX Just assert this? */ if (__predict_false(bdev->driver->verify_access == NULL)) { ret = -EPERM; goto fail1; } ret = (*bdev->driver->verify_access)(bo, file); if (ret) goto fail1; /* Success! */ *uobjp = &bo->uvmobj; *uoffsetp = (offset - ((off_t)drm_vma_node_start(&bo->base.vma_node) << PAGE_SHIFT)); return 0; fail1: ttm_bo_put(bo); fail0: KASSERT(ret); return ret; } static int ttm_bo_uvm_lookup(struct ttm_bo_device *bdev, unsigned long startpage, unsigned long npages, struct ttm_buffer_object **bop) { struct ttm_buffer_object *bo = NULL; struct drm_vma_offset_node *node; drm_vma_offset_lock_lookup(bdev->vma_manager); node = drm_vma_offset_lookup_locked(bdev->vma_manager, startpage, npages); if (node != NULL) { bo = container_of(node, struct ttm_buffer_object, base.vma_node); if (!kref_get_unless_zero(&bo->kref)) bo = NULL; } drm_vma_offset_unlock_lookup(bdev->vma_manager); if (bo == NULL) return -ENOENT; *bop = bo; return 0; }