diff options
Diffstat (limited to '')
| -rw-r--r-- | drivers/vdpa/vdpa_user/iova_domain.c | 624 |
1 files changed, 624 insertions, 0 deletions
diff --git a/drivers/vdpa/vdpa_user/iova_domain.c b/drivers/vdpa/vdpa_user/iova_domain.c new file mode 100644 index 000000000..e682bc7ee --- /dev/null +++ b/drivers/vdpa/vdpa_user/iova_domain.c @@ -0,0 +1,624 @@ +// SPDX-License-Identifier: GPL-2.0-only +/* + * MMU-based software IOTLB. + * + * Copyright (C) 2020-2021 Bytedance Inc. and/or its affiliates. All rights reserved. + * + * Author: Xie Yongji <xieyongji@bytedance.com> + * + */ + +#include <linux/slab.h> +#include <linux/file.h> +#include <linux/anon_inodes.h> +#include <linux/highmem.h> +#include <linux/vmalloc.h> +#include <linux/vdpa.h> + +#include "iova_domain.h" + +static int vduse_iotlb_add_range(struct vduse_iova_domain *domain, + u64 start, u64 last, + u64 addr, unsigned int perm, + struct file *file, u64 offset) +{ + struct vdpa_map_file *map_file; + int ret; + + map_file = kmalloc(sizeof(*map_file), GFP_ATOMIC); + if (!map_file) + return -ENOMEM; + + map_file->file = get_file(file); + map_file->offset = offset; + + ret = vhost_iotlb_add_range_ctx(domain->iotlb, start, last, + addr, perm, map_file); + if (ret) { + fput(map_file->file); + kfree(map_file); + return ret; + } + return 0; +} + +static void vduse_iotlb_del_range(struct vduse_iova_domain *domain, + u64 start, u64 last) +{ + struct vdpa_map_file *map_file; + struct vhost_iotlb_map *map; + + while ((map = vhost_iotlb_itree_first(domain->iotlb, start, last))) { + map_file = (struct vdpa_map_file *)map->opaque; + fput(map_file->file); + kfree(map_file); + vhost_iotlb_map_free(domain->iotlb, map); + } +} + +int vduse_domain_set_map(struct vduse_iova_domain *domain, + struct vhost_iotlb *iotlb) +{ + struct vdpa_map_file *map_file; + struct vhost_iotlb_map *map; + u64 start = 0ULL, last = ULLONG_MAX; + int ret; + + spin_lock(&domain->iotlb_lock); + vduse_iotlb_del_range(domain, start, last); + + for (map = vhost_iotlb_itree_first(iotlb, start, last); map; + map = vhost_iotlb_itree_next(map, start, last)) { + map_file = (struct vdpa_map_file *)map->opaque; + ret = vduse_iotlb_add_range(domain, map->start, map->last, + map->addr, map->perm, + map_file->file, + map_file->offset); + if (ret) + goto err; + } + spin_unlock(&domain->iotlb_lock); + + return 0; +err: + vduse_iotlb_del_range(domain, start, last); + spin_unlock(&domain->iotlb_lock); + return ret; +} + +void vduse_domain_clear_map(struct vduse_iova_domain *domain, + struct vhost_iotlb *iotlb) +{ + struct vhost_iotlb_map *map; + u64 start = 0ULL, last = ULLONG_MAX; + + spin_lock(&domain->iotlb_lock); + for (map = vhost_iotlb_itree_first(iotlb, start, last); map; + map = vhost_iotlb_itree_next(map, start, last)) { + vduse_iotlb_del_range(domain, map->start, map->last); + } + spin_unlock(&domain->iotlb_lock); +} + +static int vduse_domain_map_bounce_page(struct vduse_iova_domain *domain, + u64 iova, u64 size, u64 paddr) +{ + struct vduse_bounce_map *map; + u64 last = iova + size - 1; + + while (iova <= last) { + map = &domain->bounce_maps[iova >> PAGE_SHIFT]; + if (!map->bounce_page) { + map->bounce_page = alloc_page(GFP_ATOMIC); + if (!map->bounce_page) + return -ENOMEM; + } + map->orig_phys = paddr; + paddr += PAGE_SIZE; + iova += PAGE_SIZE; + } + return 0; +} + +static void vduse_domain_unmap_bounce_page(struct vduse_iova_domain *domain, + u64 iova, u64 size) +{ + struct vduse_bounce_map *map; + u64 last = iova + size - 1; + + while (iova <= last) { + map = &domain->bounce_maps[iova >> PAGE_SHIFT]; + map->orig_phys = INVALID_PHYS_ADDR; + iova += PAGE_SIZE; + } +} + +static void do_bounce(phys_addr_t orig, void *addr, size_t size, + enum dma_data_direction dir) +{ + unsigned long pfn = PFN_DOWN(orig); + unsigned int offset = offset_in_page(orig); + struct page *page; + unsigned int sz = 0; + + while (size) { + sz = min_t(size_t, PAGE_SIZE - offset, size); + + page = pfn_to_page(pfn); + if (dir == DMA_TO_DEVICE) + memcpy_from_page(addr, page, offset, sz); + else + memcpy_to_page(page, offset, addr, sz); + + size -= sz; + pfn++; + addr += sz; + offset = 0; + } +} + +static void vduse_domain_bounce(struct vduse_iova_domain *domain, + dma_addr_t iova, size_t size, + enum dma_data_direction dir) +{ + struct vduse_bounce_map *map; + unsigned int offset; + void *addr; + size_t sz; + + if (iova >= domain->bounce_size) + return; + + while (size) { + map = &domain->bounce_maps[iova >> PAGE_SHIFT]; + offset = offset_in_page(iova); + sz = min_t(size_t, PAGE_SIZE - offset, size); + + if (WARN_ON(!map->bounce_page || + map->orig_phys == INVALID_PHYS_ADDR)) + return; + + addr = kmap_local_page(map->bounce_page); + do_bounce(map->orig_phys + offset, addr + offset, sz, dir); + kunmap_local(addr); + size -= sz; + iova += sz; + } +} + +static struct page * +vduse_domain_get_coherent_page(struct vduse_iova_domain *domain, u64 iova) +{ + u64 start = iova & PAGE_MASK; + u64 last = start + PAGE_SIZE - 1; + struct vhost_iotlb_map *map; + struct page *page = NULL; + + spin_lock(&domain->iotlb_lock); + map = vhost_iotlb_itree_first(domain->iotlb, start, last); + if (!map) + goto out; + + page = pfn_to_page((map->addr + iova - map->start) >> PAGE_SHIFT); + get_page(page); +out: + spin_unlock(&domain->iotlb_lock); + + return page; +} + +static struct page * +vduse_domain_get_bounce_page(struct vduse_iova_domain *domain, u64 iova) +{ + struct vduse_bounce_map *map; + struct page *page = NULL; + + read_lock(&domain->bounce_lock); + map = &domain->bounce_maps[iova >> PAGE_SHIFT]; + if (domain->user_bounce_pages || !map->bounce_page) + goto out; + + page = map->bounce_page; + get_page(page); +out: + read_unlock(&domain->bounce_lock); + + return page; +} + +static void +vduse_domain_free_kernel_bounce_pages(struct vduse_iova_domain *domain) +{ + struct vduse_bounce_map *map; + unsigned long pfn, bounce_pfns; + + bounce_pfns = domain->bounce_size >> PAGE_SHIFT; + + for (pfn = 0; pfn < bounce_pfns; pfn++) { + map = &domain->bounce_maps[pfn]; + if (WARN_ON(map->orig_phys != INVALID_PHYS_ADDR)) + continue; + + if (!map->bounce_page) + continue; + + __free_page(map->bounce_page); + map->bounce_page = NULL; + } +} + +int vduse_domain_add_user_bounce_pages(struct vduse_iova_domain *domain, + struct page **pages, int count) +{ + struct vduse_bounce_map *map; + int i, ret; + + /* Now we don't support partial mapping */ + if (count != (domain->bounce_size >> PAGE_SHIFT)) + return -EINVAL; + + write_lock(&domain->bounce_lock); + ret = -EEXIST; + if (domain->user_bounce_pages) + goto out; + + for (i = 0; i < count; i++) { + map = &domain->bounce_maps[i]; + if (map->bounce_page) { + /* Copy kernel page to user page if it's in use */ + if (map->orig_phys != INVALID_PHYS_ADDR) + memcpy_to_page(pages[i], 0, + page_address(map->bounce_page), + PAGE_SIZE); + __free_page(map->bounce_page); + } + map->bounce_page = pages[i]; + get_page(pages[i]); + } + domain->user_bounce_pages = true; + ret = 0; +out: + write_unlock(&domain->bounce_lock); + + return ret; +} + +void vduse_domain_remove_user_bounce_pages(struct vduse_iova_domain *domain) +{ + struct vduse_bounce_map *map; + unsigned long i, count; + + write_lock(&domain->bounce_lock); + if (!domain->user_bounce_pages) + goto out; + + count = domain->bounce_size >> PAGE_SHIFT; + for (i = 0; i < count; i++) { + struct page *page = NULL; + + map = &domain->bounce_maps[i]; + if (WARN_ON(!map->bounce_page)) + continue; + + /* Copy user page to kernel page if it's in use */ + if (map->orig_phys != INVALID_PHYS_ADDR) { + page = alloc_page(GFP_ATOMIC | __GFP_NOFAIL); + memcpy_from_page(page_address(page), + map->bounce_page, 0, PAGE_SIZE); + } + put_page(map->bounce_page); + map->bounce_page = page; + } + domain->user_bounce_pages = false; +out: + write_unlock(&domain->bounce_lock); +} + +void vduse_domain_reset_bounce_map(struct vduse_iova_domain *domain) +{ + if (!domain->bounce_map) + return; + + spin_lock(&domain->iotlb_lock); + if (!domain->bounce_map) + goto unlock; + + vduse_iotlb_del_range(domain, 0, domain->bounce_size - 1); + domain->bounce_map = 0; +unlock: + spin_unlock(&domain->iotlb_lock); +} + +static int vduse_domain_init_bounce_map(struct vduse_iova_domain *domain) +{ + int ret = 0; + + if (domain->bounce_map) + return 0; + + spin_lock(&domain->iotlb_lock); + if (domain->bounce_map) + goto unlock; + + ret = vduse_iotlb_add_range(domain, 0, domain->bounce_size - 1, + 0, VHOST_MAP_RW, domain->file, 0); + if (ret) + goto unlock; + + domain->bounce_map = 1; +unlock: + spin_unlock(&domain->iotlb_lock); + return ret; +} + +static dma_addr_t +vduse_domain_alloc_iova(struct iova_domain *iovad, + unsigned long size, unsigned long limit) +{ + unsigned long shift = iova_shift(iovad); + unsigned long iova_len = iova_align(iovad, size) >> shift; + unsigned long iova_pfn; + + iova_pfn = alloc_iova_fast(iovad, iova_len, limit >> shift, true); + + return (dma_addr_t)iova_pfn << shift; +} + +static void vduse_domain_free_iova(struct iova_domain *iovad, + dma_addr_t iova, size_t size) +{ + unsigned long shift = iova_shift(iovad); + unsigned long iova_len = iova_align(iovad, size) >> shift; + + free_iova_fast(iovad, iova >> shift, iova_len); +} + +dma_addr_t vduse_domain_map_page(struct vduse_iova_domain *domain, + struct page *page, unsigned long offset, + size_t size, enum dma_data_direction dir, + unsigned long attrs) +{ + struct iova_domain *iovad = &domain->stream_iovad; + unsigned long limit = domain->bounce_size - 1; + phys_addr_t pa = page_to_phys(page) + offset; + dma_addr_t iova = vduse_domain_alloc_iova(iovad, size, limit); + + if (!iova) + return DMA_MAPPING_ERROR; + + if (vduse_domain_init_bounce_map(domain)) + goto err; + + read_lock(&domain->bounce_lock); + if (vduse_domain_map_bounce_page(domain, (u64)iova, (u64)size, pa)) + goto err_unlock; + + if (dir == DMA_TO_DEVICE || dir == DMA_BIDIRECTIONAL) + vduse_domain_bounce(domain, iova, size, DMA_TO_DEVICE); + + read_unlock(&domain->bounce_lock); + + return iova; +err_unlock: + read_unlock(&domain->bounce_lock); +err: + vduse_domain_free_iova(iovad, iova, size); + return DMA_MAPPING_ERROR; +} + +void vduse_domain_unmap_page(struct vduse_iova_domain *domain, + dma_addr_t dma_addr, size_t size, + enum dma_data_direction dir, unsigned long attrs) +{ + struct iova_domain *iovad = &domain->stream_iovad; + + read_lock(&domain->bounce_lock); + if (dir == DMA_FROM_DEVICE || dir == DMA_BIDIRECTIONAL) + vduse_domain_bounce(domain, dma_addr, size, DMA_FROM_DEVICE); + + vduse_domain_unmap_bounce_page(domain, (u64)dma_addr, (u64)size); + read_unlock(&domain->bounce_lock); + vduse_domain_free_iova(iovad, dma_addr, size); +} + +void *vduse_domain_alloc_coherent(struct vduse_iova_domain *domain, + size_t size, dma_addr_t *dma_addr, + gfp_t flag, unsigned long attrs) +{ + struct iova_domain *iovad = &domain->consistent_iovad; + unsigned long limit = domain->iova_limit; + dma_addr_t iova = vduse_domain_alloc_iova(iovad, size, limit); + void *orig = alloc_pages_exact(size, flag); + + if (!iova || !orig) + goto err; + + spin_lock(&domain->iotlb_lock); + if (vduse_iotlb_add_range(domain, (u64)iova, (u64)iova + size - 1, + virt_to_phys(orig), VHOST_MAP_RW, + domain->file, (u64)iova)) { + spin_unlock(&domain->iotlb_lock); + goto err; + } + spin_unlock(&domain->iotlb_lock); + + *dma_addr = iova; + + return orig; +err: + *dma_addr = DMA_MAPPING_ERROR; + if (orig) + free_pages_exact(orig, size); + if (iova) + vduse_domain_free_iova(iovad, iova, size); + + return NULL; +} + +void vduse_domain_free_coherent(struct vduse_iova_domain *domain, size_t size, + void *vaddr, dma_addr_t dma_addr, + unsigned long attrs) +{ + struct iova_domain *iovad = &domain->consistent_iovad; + struct vhost_iotlb_map *map; + struct vdpa_map_file *map_file; + phys_addr_t pa; + + spin_lock(&domain->iotlb_lock); + map = vhost_iotlb_itree_first(domain->iotlb, (u64)dma_addr, + (u64)dma_addr + size - 1); + if (WARN_ON(!map)) { + spin_unlock(&domain->iotlb_lock); + return; + } + map_file = (struct vdpa_map_file *)map->opaque; + fput(map_file->file); + kfree(map_file); + pa = map->addr; + vhost_iotlb_map_free(domain->iotlb, map); + spin_unlock(&domain->iotlb_lock); + + vduse_domain_free_iova(iovad, dma_addr, size); + free_pages_exact(phys_to_virt(pa), size); +} + +static vm_fault_t vduse_domain_mmap_fault(struct vm_fault *vmf) +{ + struct vduse_iova_domain *domain = vmf->vma->vm_private_data; + unsigned long iova = vmf->pgoff << PAGE_SHIFT; + struct page *page; + + if (!domain) + return VM_FAULT_SIGBUS; + + if (iova < domain->bounce_size) + page = vduse_domain_get_bounce_page(domain, iova); + else + page = vduse_domain_get_coherent_page(domain, iova); + + if (!page) + return VM_FAULT_SIGBUS; + + vmf->page = page; + + return 0; +} + +static const struct vm_operations_struct vduse_domain_mmap_ops = { + .fault = vduse_domain_mmap_fault, +}; + +static int vduse_domain_mmap(struct file *file, struct vm_area_struct *vma) +{ + struct vduse_iova_domain *domain = file->private_data; + + vma->vm_flags |= VM_DONTDUMP | VM_DONTEXPAND; + vma->vm_private_data = domain; + vma->vm_ops = &vduse_domain_mmap_ops; + + return 0; +} + +static int vduse_domain_release(struct inode *inode, struct file *file) +{ + struct vduse_iova_domain *domain = file->private_data; + + spin_lock(&domain->iotlb_lock); + vduse_iotlb_del_range(domain, 0, ULLONG_MAX); + vduse_domain_remove_user_bounce_pages(domain); + vduse_domain_free_kernel_bounce_pages(domain); + spin_unlock(&domain->iotlb_lock); + put_iova_domain(&domain->stream_iovad); + put_iova_domain(&domain->consistent_iovad); + vhost_iotlb_free(domain->iotlb); + vfree(domain->bounce_maps); + kfree(domain); + + return 0; +} + +static const struct file_operations vduse_domain_fops = { + .owner = THIS_MODULE, + .mmap = vduse_domain_mmap, + .release = vduse_domain_release, +}; + +void vduse_domain_destroy(struct vduse_iova_domain *domain) +{ + fput(domain->file); +} + +struct vduse_iova_domain * +vduse_domain_create(unsigned long iova_limit, size_t bounce_size) +{ + struct vduse_iova_domain *domain; + struct file *file; + struct vduse_bounce_map *map; + unsigned long pfn, bounce_pfns; + int ret; + + bounce_pfns = PAGE_ALIGN(bounce_size) >> PAGE_SHIFT; + if (iova_limit <= bounce_size) + return NULL; + + domain = kzalloc(sizeof(*domain), GFP_KERNEL); + if (!domain) + return NULL; + + domain->iotlb = vhost_iotlb_alloc(0, 0); + if (!domain->iotlb) + goto err_iotlb; + + domain->iova_limit = iova_limit; + domain->bounce_size = PAGE_ALIGN(bounce_size); + domain->bounce_maps = vzalloc(bounce_pfns * + sizeof(struct vduse_bounce_map)); + if (!domain->bounce_maps) + goto err_map; + + for (pfn = 0; pfn < bounce_pfns; pfn++) { + map = &domain->bounce_maps[pfn]; + map->orig_phys = INVALID_PHYS_ADDR; + } + file = anon_inode_getfile("[vduse-domain]", &vduse_domain_fops, + domain, O_RDWR); + if (IS_ERR(file)) + goto err_file; + + domain->file = file; + rwlock_init(&domain->bounce_lock); + spin_lock_init(&domain->iotlb_lock); + init_iova_domain(&domain->stream_iovad, + PAGE_SIZE, IOVA_START_PFN); + ret = iova_domain_init_rcaches(&domain->stream_iovad); + if (ret) + goto err_iovad_stream; + init_iova_domain(&domain->consistent_iovad, + PAGE_SIZE, bounce_pfns); + ret = iova_domain_init_rcaches(&domain->consistent_iovad); + if (ret) + goto err_iovad_consistent; + + return domain; +err_iovad_consistent: + put_iova_domain(&domain->stream_iovad); +err_iovad_stream: + fput(file); +err_file: + vfree(domain->bounce_maps); +err_map: + vhost_iotlb_free(domain->iotlb); +err_iotlb: + kfree(domain); + return NULL; +} + +int vduse_domain_init(void) +{ + return iova_cache_get(); +} + +void vduse_domain_exit(void) +{ + iova_cache_put(); +} |