diff options
Diffstat (limited to 'drivers/accel/amdxdna/amdxdna_ubuf.c')
| -rw-r--r-- | drivers/accel/amdxdna/amdxdna_ubuf.c | 232 |
1 files changed, 232 insertions, 0 deletions
diff --git a/drivers/accel/amdxdna/amdxdna_ubuf.c b/drivers/accel/amdxdna/amdxdna_ubuf.c new file mode 100644 index 000000000000..077b2261cf2a --- /dev/null +++ b/drivers/accel/amdxdna/amdxdna_ubuf.c @@ -0,0 +1,232 @@ +// SPDX-License-Identifier: GPL-2.0 +/* + * Copyright (C) 2025, Advanced Micro Devices, Inc. + */ + +#include <drm/amdxdna_accel.h> +#include <drm/drm_device.h> +#include <drm/drm_print.h> +#include <linux/dma-buf.h> +#include <linux/pagemap.h> +#include <linux/vmalloc.h> + +#include "amdxdna_pci_drv.h" +#include "amdxdna_ubuf.h" + +struct amdxdna_ubuf_priv { + struct page **pages; + u64 nr_pages; + enum amdxdna_ubuf_flag flags; + struct mm_struct *mm; +}; + +static struct sg_table *amdxdna_ubuf_map(struct dma_buf_attachment *attach, + enum dma_data_direction direction) +{ + struct amdxdna_ubuf_priv *ubuf = attach->dmabuf->priv; + struct sg_table *sg; + int ret; + + sg = kzalloc(sizeof(*sg), GFP_KERNEL); + if (!sg) + return ERR_PTR(-ENOMEM); + + ret = sg_alloc_table_from_pages(sg, ubuf->pages, ubuf->nr_pages, 0, + ubuf->nr_pages << PAGE_SHIFT, GFP_KERNEL); + if (ret) + return ERR_PTR(ret); + + if (ubuf->flags & AMDXDNA_UBUF_FLAG_MAP_DMA) { + ret = dma_map_sgtable(attach->dev, sg, direction, 0); + if (ret) + return ERR_PTR(ret); + } + + return sg; +} + +static void amdxdna_ubuf_unmap(struct dma_buf_attachment *attach, + struct sg_table *sg, + enum dma_data_direction direction) +{ + struct amdxdna_ubuf_priv *ubuf = attach->dmabuf->priv; + + if (ubuf->flags & AMDXDNA_UBUF_FLAG_MAP_DMA) + dma_unmap_sgtable(attach->dev, sg, direction, 0); + + sg_free_table(sg); + kfree(sg); +} + +static void amdxdna_ubuf_release(struct dma_buf *dbuf) +{ + struct amdxdna_ubuf_priv *ubuf = dbuf->priv; + + unpin_user_pages(ubuf->pages, ubuf->nr_pages); + kvfree(ubuf->pages); + atomic64_sub(ubuf->nr_pages, &ubuf->mm->pinned_vm); + mmdrop(ubuf->mm); + kfree(ubuf); +} + +static vm_fault_t amdxdna_ubuf_vm_fault(struct vm_fault *vmf) +{ + struct vm_area_struct *vma = vmf->vma; + struct amdxdna_ubuf_priv *ubuf; + unsigned long pfn; + pgoff_t pgoff; + + ubuf = vma->vm_private_data; + pgoff = (vmf->address - vma->vm_start) >> PAGE_SHIFT; + + pfn = page_to_pfn(ubuf->pages[pgoff]); + return vmf_insert_pfn(vma, vmf->address, pfn); +} + +static const struct vm_operations_struct amdxdna_ubuf_vm_ops = { + .fault = amdxdna_ubuf_vm_fault, +}; + +static int amdxdna_ubuf_mmap(struct dma_buf *dbuf, struct vm_area_struct *vma) +{ + struct amdxdna_ubuf_priv *ubuf = dbuf->priv; + + vma->vm_ops = &amdxdna_ubuf_vm_ops; + vma->vm_private_data = ubuf; + vm_flags_set(vma, VM_PFNMAP | VM_DONTEXPAND | VM_DONTDUMP); + + return 0; +} + +static int amdxdna_ubuf_vmap(struct dma_buf *dbuf, struct iosys_map *map) +{ + struct amdxdna_ubuf_priv *ubuf = dbuf->priv; + void *kva; + + kva = vmap(ubuf->pages, ubuf->nr_pages, VM_MAP, PAGE_KERNEL); + if (!kva) + return -EINVAL; + + iosys_map_set_vaddr(map, kva); + return 0; +} + +static void amdxdna_ubuf_vunmap(struct dma_buf *dbuf, struct iosys_map *map) +{ + vunmap(map->vaddr); +} + +static const struct dma_buf_ops amdxdna_ubuf_dmabuf_ops = { + .map_dma_buf = amdxdna_ubuf_map, + .unmap_dma_buf = amdxdna_ubuf_unmap, + .release = amdxdna_ubuf_release, + .mmap = amdxdna_ubuf_mmap, + .vmap = amdxdna_ubuf_vmap, + .vunmap = amdxdna_ubuf_vunmap, +}; + +struct dma_buf *amdxdna_get_ubuf(struct drm_device *dev, + enum amdxdna_ubuf_flag flags, + u32 num_entries, void __user *va_entries) +{ + struct amdxdna_dev *xdna = to_xdna_dev(dev); + unsigned long lock_limit, new_pinned; + struct amdxdna_drm_va_entry *va_ent; + struct amdxdna_ubuf_priv *ubuf; + u32 npages, start = 0; + struct dma_buf *dbuf; + int i, ret; + DEFINE_DMA_BUF_EXPORT_INFO(exp_info); + + if (!can_do_mlock()) + return ERR_PTR(-EPERM); + + ubuf = kzalloc(sizeof(*ubuf), GFP_KERNEL); + if (!ubuf) + return ERR_PTR(-ENOMEM); + + ubuf->flags = flags; + ubuf->mm = current->mm; + mmgrab(ubuf->mm); + + va_ent = kvcalloc(num_entries, sizeof(*va_ent), GFP_KERNEL); + if (!va_ent) { + ret = -ENOMEM; + goto free_ubuf; + } + + if (copy_from_user(va_ent, va_entries, sizeof(*va_ent) * num_entries)) { + XDNA_DBG(xdna, "Access va entries failed"); + ret = -EINVAL; + goto free_ent; + } + + for (i = 0, exp_info.size = 0; i < num_entries; i++) { + if (!IS_ALIGNED(va_ent[i].vaddr, PAGE_SIZE) || + !IS_ALIGNED(va_ent[i].len, PAGE_SIZE)) { + XDNA_ERR(xdna, "Invalid address or len %llx, %llx", + va_ent[i].vaddr, va_ent[i].len); + ret = -EINVAL; + goto free_ent; + } + + exp_info.size += va_ent[i].len; + } + + ubuf->nr_pages = exp_info.size >> PAGE_SHIFT; + lock_limit = rlimit(RLIMIT_MEMLOCK) >> PAGE_SHIFT; + new_pinned = atomic64_add_return(ubuf->nr_pages, &ubuf->mm->pinned_vm); + if (new_pinned > lock_limit && !capable(CAP_IPC_LOCK)) { + XDNA_DBG(xdna, "New pin %ld, limit %ld, cap %d", + new_pinned, lock_limit, capable(CAP_IPC_LOCK)); + ret = -ENOMEM; + goto sub_pin_cnt; + } + + ubuf->pages = kvmalloc_array(ubuf->nr_pages, sizeof(*ubuf->pages), GFP_KERNEL); + if (!ubuf->pages) { + ret = -ENOMEM; + goto sub_pin_cnt; + } + + for (i = 0; i < num_entries; i++) { + npages = va_ent[i].len >> PAGE_SHIFT; + + ret = pin_user_pages_fast(va_ent[i].vaddr, npages, + FOLL_WRITE | FOLL_LONGTERM, + &ubuf->pages[start]); + if (ret < 0 || ret != npages) { + ret = -ENOMEM; + XDNA_ERR(xdna, "Failed to pin pages ret %d", ret); + goto destroy_pages; + } + + start += ret; + } + + exp_info.ops = &amdxdna_ubuf_dmabuf_ops; + exp_info.priv = ubuf; + exp_info.flags = O_RDWR | O_CLOEXEC; + + dbuf = dma_buf_export(&exp_info); + if (IS_ERR(dbuf)) { + ret = PTR_ERR(dbuf); + goto destroy_pages; + } + kvfree(va_ent); + + return dbuf; + +destroy_pages: + if (start) + unpin_user_pages(ubuf->pages, start); + kvfree(ubuf->pages); +sub_pin_cnt: + atomic64_sub(ubuf->nr_pages, &ubuf->mm->pinned_vm); +free_ent: + kvfree(va_ent); +free_ubuf: + mmdrop(ubuf->mm); + kfree(ubuf); + return ERR_PTR(ret); +} |