diff --git a/drivers/gpu/drm/exynos/Kconfig b/drivers/gpu/drm/exynos/Kconfig index df0b61a60501..bd1a4156f647 100644 --- a/drivers/gpu/drm/exynos/Kconfig +++ b/drivers/gpu/drm/exynos/Kconfig @@ -77,6 +77,7 @@ config DRM_EXYNOS_VIDI config DRM_EXYNOS_G2D bool "Exynos DRM G2D" depends on DRM_EXYNOS && !VIDEO_SAMSUNG_S5P_G2D + select FRAME_VECTOR help Choose this option if you want to use Exynos G2D for DRM. diff --git a/drivers/gpu/drm/exynos/exynos_drm_g2d.c b/drivers/gpu/drm/exynos/exynos_drm_g2d.c index 535b4ad6c4b1..3734c34aed16 100644 --- a/drivers/gpu/drm/exynos/exynos_drm_g2d.c +++ b/drivers/gpu/drm/exynos/exynos_drm_g2d.c @@ -194,10 +194,8 @@ struct g2d_cmdlist_userptr { dma_addr_t dma_addr; unsigned long userptr; unsigned long size; - struct page **pages; - unsigned int npages; + struct frame_vector *vec; struct sg_table *sgt; - struct vm_area_struct *vma; atomic_t refcount; bool in_pool; bool out_of_list; @@ -367,6 +365,7 @@ static void g2d_userptr_put_dma_addr(struct drm_device *drm_dev, { struct g2d_cmdlist_userptr *g2d_userptr = (struct g2d_cmdlist_userptr *)obj; + struct page **pages; if (!obj) return; @@ -386,19 +385,21 @@ static void g2d_userptr_put_dma_addr(struct drm_device *drm_dev, exynos_gem_unmap_sgt_from_dma(drm_dev, g2d_userptr->sgt, DMA_BIDIRECTIONAL); - exynos_gem_put_pages_to_userptr(g2d_userptr->pages, - g2d_userptr->npages, - g2d_userptr->vma); + pages = frame_vector_pages(g2d_userptr->vec); + if (!IS_ERR(pages)) { + int i; - exynos_gem_put_vma(g2d_userptr->vma); + for (i = 0; i < frame_vector_count(g2d_userptr->vec); i++) + set_page_dirty_lock(pages[i]); + } + put_vaddr_frames(g2d_userptr->vec); + frame_vector_destroy(g2d_userptr->vec); if (!g2d_userptr->out_of_list) list_del_init(&g2d_userptr->list); sg_free_table(g2d_userptr->sgt); kfree(g2d_userptr->sgt); - - drm_free_large(g2d_userptr->pages); kfree(g2d_userptr); } @@ -412,9 +413,7 @@ static dma_addr_t *g2d_userptr_get_dma_addr(struct drm_device *drm_dev, struct exynos_drm_g2d_private *g2d_priv = file_priv->g2d_priv; struct g2d_cmdlist_userptr *g2d_userptr; struct g2d_data *g2d; - struct page **pages; struct sg_table *sgt; - struct vm_area_struct *vma; unsigned long start, end; unsigned int npages, offset; int ret; @@ -460,65 +459,40 @@ static dma_addr_t *g2d_userptr_get_dma_addr(struct drm_device *drm_dev, return ERR_PTR(-ENOMEM); atomic_set(&g2d_userptr->refcount, 1); + g2d_userptr->size = size; start = userptr & PAGE_MASK; offset = userptr & ~PAGE_MASK; end = PAGE_ALIGN(userptr + size); npages = (end - start) >> PAGE_SHIFT; - g2d_userptr->npages = npages; - - pages = drm_calloc_large(npages, sizeof(struct page *)); - if (!pages) { - DRM_ERROR("failed to allocate pages.\n"); + g2d_userptr->vec = frame_vector_create(npages); + if (!g2d_userptr->vec) { ret = -ENOMEM; goto err_free; } - down_read(¤t->mm->mmap_sem); - vma = find_vma(current->mm, userptr); - if (!vma) { - up_read(¤t->mm->mmap_sem); - DRM_ERROR("failed to get vm region.\n"); - ret = -EFAULT; - goto err_free_pages; - } - - if (vma->vm_end < userptr + size) { - up_read(¤t->mm->mmap_sem); - DRM_ERROR("vma is too small.\n"); - ret = -EFAULT; - goto err_free_pages; - } - - g2d_userptr->vma = exynos_gem_get_vma(vma); - if (!g2d_userptr->vma) { - up_read(¤t->mm->mmap_sem); - DRM_ERROR("failed to copy vma.\n"); - ret = -ENOMEM; - goto err_free_pages; - } - - g2d_userptr->size = size; - - ret = exynos_gem_get_pages_from_userptr(start & PAGE_MASK, - npages, pages, vma); - if (ret < 0) { - up_read(¤t->mm->mmap_sem); + ret = get_vaddr_frames(start, npages, true, true, g2d_userptr->vec); + if (ret != npages) { DRM_ERROR("failed to get user pages from userptr.\n"); - goto err_put_vma; + if (ret < 0) + goto err_destroy_framevec; + ret = -EFAULT; + goto err_put_framevec; + } + if (frame_vector_to_pages(g2d_userptr->vec) < 0) { + ret = -EFAULT; + goto err_put_framevec; } - - up_read(¤t->mm->mmap_sem); - g2d_userptr->pages = pages; sgt = kzalloc(sizeof(*sgt), GFP_KERNEL); if (!sgt) { ret = -ENOMEM; - goto err_free_userptr; + goto err_put_framevec; } - ret = sg_alloc_table_from_pages(sgt, pages, npages, offset, - size, GFP_KERNEL); + ret = sg_alloc_table_from_pages(sgt, + frame_vector_pages(g2d_userptr->vec), + npages, offset, size, GFP_KERNEL); if (ret < 0) { DRM_ERROR("failed to get sgt from pages.\n"); goto err_free_sgt; @@ -553,16 +527,11 @@ static dma_addr_t *g2d_userptr_get_dma_addr(struct drm_device *drm_dev, err_free_sgt: kfree(sgt); -err_free_userptr: - exynos_gem_put_pages_to_userptr(g2d_userptr->pages, - g2d_userptr->npages, - g2d_userptr->vma); +err_put_framevec: + put_vaddr_frames(g2d_userptr->vec); -err_put_vma: - exynos_gem_put_vma(g2d_userptr->vma); - -err_free_pages: - drm_free_large(pages); +err_destroy_framevec: + frame_vector_destroy(g2d_userptr->vec); err_free: kfree(g2d_userptr); diff --git a/drivers/gpu/drm/exynos/exynos_drm_gem.c b/drivers/gpu/drm/exynos/exynos_drm_gem.c index 62b9ea1b07fb..f12fbc36b120 100644 --- a/drivers/gpu/drm/exynos/exynos_drm_gem.c +++ b/drivers/gpu/drm/exynos/exynos_drm_gem.c @@ -366,103 +366,6 @@ int exynos_drm_gem_get_ioctl(struct drm_device *dev, void *data, return 0; } -struct vm_area_struct *exynos_gem_get_vma(struct vm_area_struct *vma) -{ - struct vm_area_struct *vma_copy; - - vma_copy = kmalloc(sizeof(*vma_copy), GFP_KERNEL); - if (!vma_copy) - return NULL; - - if (vma->vm_ops && vma->vm_ops->open) - vma->vm_ops->open(vma); - - if (vma->vm_file) - get_file(vma->vm_file); - - memcpy(vma_copy, vma, sizeof(*vma)); - - vma_copy->vm_mm = NULL; - vma_copy->vm_next = NULL; - vma_copy->vm_prev = NULL; - - return vma_copy; -} - -void exynos_gem_put_vma(struct vm_area_struct *vma) -{ - if (!vma) - return; - - if (vma->vm_ops && vma->vm_ops->close) - vma->vm_ops->close(vma); - - if (vma->vm_file) - fput(vma->vm_file); - - kfree(vma); -} - -int exynos_gem_get_pages_from_userptr(unsigned long start, - unsigned int npages, - struct page **pages, - struct vm_area_struct *vma) -{ - int get_npages; - - /* the memory region mmaped with VM_PFNMAP. */ - if (vma_is_io(vma)) { - unsigned int i; - - for (i = 0; i < npages; ++i, start += PAGE_SIZE) { - unsigned long pfn; - int ret = follow_pfn(vma, start, &pfn); - if (ret) - return ret; - - pages[i] = pfn_to_page(pfn); - } - - if (i != npages) { - DRM_ERROR("failed to get user_pages.\n"); - return -EINVAL; - } - - return 0; - } - - get_npages = get_user_pages(current, current->mm, start, - npages, 1, 1, pages, NULL); - get_npages = max(get_npages, 0); - if (get_npages != npages) { - DRM_ERROR("failed to get user_pages.\n"); - while (get_npages) - put_page(pages[--get_npages]); - return -EFAULT; - } - - return 0; -} - -void exynos_gem_put_pages_to_userptr(struct page **pages, - unsigned int npages, - struct vm_area_struct *vma) -{ - if (!vma_is_io(vma)) { - unsigned int i; - - for (i = 0; i < npages; i++) { - set_page_dirty_lock(pages[i]); - - /* - * undo the reference we took when populating - * the table. - */ - put_page(pages[i]); - } - } -} - int exynos_gem_map_sgt_with_dma(struct drm_device *drm_dev, struct sg_table *sgt, enum dma_data_direction dir) diff --git a/drivers/media/platform/omap/Kconfig b/drivers/media/platform/omap/Kconfig index dc2aaab54aef..217d613b0fe7 100644 --- a/drivers/media/platform/omap/Kconfig +++ b/drivers/media/platform/omap/Kconfig @@ -10,6 +10,7 @@ config VIDEO_OMAP2_VOUT select OMAP2_DSS if HAS_IOMEM && ARCH_OMAP2PLUS select OMAP2_VRFB if ARCH_OMAP2 || ARCH_OMAP3 select VIDEO_OMAP2_VOUT_VRFB if VIDEO_OMAP2_VOUT && OMAP2_VRFB + select FRAME_VECTOR default n ---help--- V4L2 Display driver support for OMAP2/3 based boards. diff --git a/drivers/media/platform/omap/omap_vout.c b/drivers/media/platform/omap/omap_vout.c index de2474e1132d..70c28d19ea04 100644 --- a/drivers/media/platform/omap/omap_vout.c +++ b/drivers/media/platform/omap/omap_vout.c @@ -195,46 +195,34 @@ static int omap_vout_try_format(struct v4l2_pix_format *pix) } /* - * omap_vout_uservirt_to_phys: This inline function is used to convert user - * space virtual address to physical address. + * omap_vout_get_userptr: Convert user space virtual address to physical + * address. */ -static unsigned long omap_vout_uservirt_to_phys(unsigned long virtp) +static int omap_vout_get_userptr(struct videobuf_buffer *vb, u32 virtp, + u32 *physp) { - unsigned long physp = 0; - struct vm_area_struct *vma; - struct mm_struct *mm = current->mm; + struct frame_vector *vec; + int ret; /* For kernel direct-mapped memory, take the easy way */ - if (virtp >= PAGE_OFFSET) - return virt_to_phys((void *) virtp); - - down_read(¤t->mm->mmap_sem); - vma = find_vma(mm, virtp); - if (vma && (vma->vm_flags & VM_IO) && vma->vm_pgoff) { - /* this will catch, kernel-allocated, mmaped-to-usermode - addresses */ - physp = (vma->vm_pgoff << PAGE_SHIFT) + (virtp - vma->vm_start); - up_read(¤t->mm->mmap_sem); - } else { - /* otherwise, use get_user_pages() for general userland pages */ - int res, nr_pages = 1; - struct page *pages; - - res = get_user_pages(current, current->mm, virtp, nr_pages, 1, - 0, &pages, NULL); - up_read(¤t->mm->mmap_sem); - - if (res == nr_pages) { - physp = __pa(page_address(&pages[0]) + - (virtp & ~PAGE_MASK)); - } else { - printk(KERN_WARNING VOUT_NAME - "get_user_pages failed\n"); - return 0; - } + if (virtp >= PAGE_OFFSET) { + *physp = virt_to_phys((void *)virtp); + return 0; } - return physp; + vec = frame_vector_create(1); + if (!vec) + return -ENOMEM; + + ret = get_vaddr_frames(virtp, 1, true, false, vec); + if (ret != 1) { + frame_vector_destroy(vec); + return -EINVAL; + } + *physp = __pfn_to_phys(frame_vector_pfns(vec)[0]); + vb->priv = vec; + + return 0; } /* @@ -784,11 +772,15 @@ static int omap_vout_buffer_prepare(struct videobuf_queue *q, * address of the buffer */ if (V4L2_MEMORY_USERPTR == vb->memory) { + int ret; + if (0 == vb->baddr) return -EINVAL; /* Physical address */ - vout->queued_buf_addr[vb->i] = (u8 *) - omap_vout_uservirt_to_phys(vb->baddr); + ret = omap_vout_get_userptr(vb, vb->baddr, + (u32 *)&vout->queued_buf_addr[vb->i]); + if (ret < 0) + return ret; } else { unsigned long addr, dma_addr; unsigned long size; @@ -834,12 +826,13 @@ static void omap_vout_buffer_queue(struct videobuf_queue *q, static void omap_vout_buffer_release(struct videobuf_queue *q, struct videobuf_buffer *vb) { - struct omap_vout_device *vout = q->priv_data; - vb->state = VIDEOBUF_NEEDS_INIT; + if (vb->memory == V4L2_MEMORY_USERPTR && vb->priv) { + struct frame_vector *vec = vb->priv; - if (V4L2_MEMORY_MMAP != vout->memory) - return; + put_vaddr_frames(vec); + frame_vector_destroy(vec); + } } /* diff --git a/drivers/media/v4l2-core/Kconfig b/drivers/media/v4l2-core/Kconfig index b4b022933e29..82876a67f144 100644 --- a/drivers/media/v4l2-core/Kconfig +++ b/drivers/media/v4l2-core/Kconfig @@ -84,6 +84,7 @@ config VIDEOBUF2_CORE config VIDEOBUF2_MEMOPS tristate + select FRAME_VECTOR config VIDEOBUF2_DMA_CONTIG tristate diff --git a/drivers/media/v4l2-core/videobuf2-core.c b/drivers/media/v4l2-core/videobuf2-core.c index f1022d810d22..4f59b7ec05d0 100644 --- a/drivers/media/v4l2-core/videobuf2-core.c +++ b/drivers/media/v4l2-core/videobuf2-core.c @@ -1691,9 +1691,7 @@ static int __buf_prepare(struct vb2_buffer *vb, const struct v4l2_buffer *b) ret = __qbuf_mmap(vb, b); break; case V4L2_MEMORY_USERPTR: - down_read(¤t->mm->mmap_sem); ret = __qbuf_userptr(vb, b); - up_read(¤t->mm->mmap_sem); break; case V4L2_MEMORY_DMABUF: ret = __qbuf_dmabuf(vb, b); diff --git a/drivers/media/v4l2-core/videobuf2-dma-contig.c b/drivers/media/v4l2-core/videobuf2-dma-contig.c index 94c1e6455d36..2397ceb1dc6b 100644 --- a/drivers/media/v4l2-core/videobuf2-dma-contig.c +++ b/drivers/media/v4l2-core/videobuf2-dma-contig.c @@ -32,15 +32,13 @@ struct vb2_dc_buf { dma_addr_t dma_addr; enum dma_data_direction dma_dir; struct sg_table *dma_sgt; + struct frame_vector *vec; /* MMAP related */ struct vb2_vmarea_handler handler; atomic_t refcount; struct sg_table *sgt_base; - /* USERPTR related */ - struct vm_area_struct *vma; - /* DMABUF related */ struct dma_buf_attachment *db_attach; }; @@ -49,24 +47,6 @@ struct vb2_dc_buf { /* scatterlist table functions */ /*********************************************/ - -static void vb2_dc_sgt_foreach_page(struct sg_table *sgt, - void (*cb)(struct page *pg)) -{ - struct scatterlist *s; - unsigned int i; - - for_each_sg(sgt->sgl, s, sgt->orig_nents, i) { - struct page *page = sg_page(s); - unsigned int n_pages = PAGE_ALIGN(s->offset + s->length) - >> PAGE_SHIFT; - unsigned int j; - - for (j = 0; j < n_pages; ++j, ++page) - cb(page); - } -} - static unsigned long vb2_dc_get_contiguous_size(struct sg_table *sgt) { struct scatterlist *s; @@ -429,92 +409,12 @@ static struct dma_buf *vb2_dc_get_dmabuf(void *buf_priv, unsigned long flags) /* callbacks for USERPTR buffers */ /*********************************************/ -static inline int vma_is_io(struct vm_area_struct *vma) -{ - return !!(vma->vm_flags & (VM_IO | VM_PFNMAP)); -} - -static int vb2_dc_get_user_pfn(unsigned long start, int n_pages, - struct vm_area_struct *vma, unsigned long *res) -{ - unsigned long pfn, start_pfn, prev_pfn; - unsigned int i; - int ret; - - if (!vma_is_io(vma)) - return -EFAULT; - - ret = follow_pfn(vma, start, &pfn); - if (ret) - return ret; - - start_pfn = pfn; - start += PAGE_SIZE; - - for (i = 1; i < n_pages; ++i, start += PAGE_SIZE) { - prev_pfn = pfn; - ret = follow_pfn(vma, start, &pfn); - - if (ret) { - pr_err("no page for address %lu\n", start); - return ret; - } - if (pfn != prev_pfn + 1) - return -EINVAL; - } - - *res = start_pfn; - return 0; -} - -static int vb2_dc_get_user_pages(unsigned long start, struct page **pages, - int n_pages, struct vm_area_struct *vma, - enum dma_data_direction dma_dir) -{ - if (vma_is_io(vma)) { - unsigned int i; - - for (i = 0; i < n_pages; ++i, start += PAGE_SIZE) { - unsigned long pfn; - int ret = follow_pfn(vma, start, &pfn); - - if (!pfn_valid(pfn)) - return -EINVAL; - - if (ret) { - pr_err("no page for address %lu\n", start); - return ret; - } - pages[i] = pfn_to_page(pfn); - } - } else { - int n; - - n = get_user_pages(current, current->mm, start & PAGE_MASK, - n_pages, dma_dir == DMA_FROM_DEVICE, 1, pages, NULL); - /* negative error means that no page was pinned */ - n = max(n, 0); - if (n != n_pages) { - pr_err("got only %d of %d user pages\n", n, n_pages); - while (n) - put_page(pages[--n]); - return -EFAULT; - } - } - - return 0; -} - -static void vb2_dc_put_dirty_page(struct page *page) -{ - set_page_dirty_lock(page); - put_page(page); -} - static void vb2_dc_put_userptr(void *buf_priv) { struct vb2_dc_buf *buf = buf_priv; struct sg_table *sgt = buf->dma_sgt; + int i; + struct page **pages; if (sgt) { DEFINE_DMA_ATTRS(attrs); @@ -526,13 +426,15 @@ static void vb2_dc_put_userptr(void *buf_priv) */ dma_unmap_sg_attrs(buf->dev, sgt->sgl, sgt->orig_nents, buf->dma_dir, &attrs); - if (!vma_is_io(buf->vma)) - vb2_dc_sgt_foreach_page(sgt, vb2_dc_put_dirty_page); - + pages = frame_vector_pages(buf->vec); + /* sgt should exist only if vector contains pages... */ + BUG_ON(IS_ERR(pages)); + for (i = 0; i < frame_vector_count(buf->vec); i++) + set_page_dirty_lock(pages[i]); sg_free_table(sgt); kfree(sgt); } - vb2_put_vma(buf->vma); + vb2_destroy_framevec(buf->vec); kfree(buf); } @@ -572,13 +474,10 @@ static void *vb2_dc_get_userptr(void *alloc_ctx, unsigned long vaddr, { struct vb2_dc_conf *conf = alloc_ctx; struct vb2_dc_buf *buf; - unsigned long start; - unsigned long end; + struct frame_vector *vec; unsigned long offset; - struct page **pages; - int n_pages; + int n_pages, i; int ret = 0; - struct vm_area_struct *vma; struct sg_table *sgt; unsigned long contig_size; unsigned long dma_align = dma_get_cache_alignment(); @@ -604,72 +503,43 @@ static void *vb2_dc_get_userptr(void *alloc_ctx, unsigned long vaddr, buf->dev = conf->dev; buf->dma_dir = dma_dir; - start = vaddr & PAGE_MASK; offset = vaddr & ~PAGE_MASK; - end = PAGE_ALIGN(vaddr + size); - n_pages = (end - start) >> PAGE_SHIFT; - - pages = kmalloc(n_pages * sizeof(pages[0]), GFP_KERNEL); - if (!pages) { - ret = -ENOMEM; - pr_err("failed to allocate pages table\n"); + vec = vb2_create_framevec(vaddr, size, dma_dir == DMA_FROM_DEVICE); + if (IS_ERR(vec)) { + ret = PTR_ERR(vec); goto fail_buf; } + buf->vec = vec; + n_pages = frame_vector_count(vec); + ret = frame_vector_to_pages(vec); + if (ret < 0) { + unsigned long *nums = frame_vector_pfns(vec); - /* current->mm->mmap_sem is taken by videobuf2 core */ - vma = find_vma(current->mm, vaddr); - if (!vma) { - pr_err("no vma for address %lu\n", vaddr); - ret = -EFAULT; - goto fail_pages; - } - - if (vma->vm_end < vaddr + size) { - pr_err("vma at %lu is too small for %lu bytes\n", vaddr, size); - ret = -EFAULT; - goto fail_pages; - } - - buf->vma = vb2_get_vma(vma); - if (!buf->vma) { - pr_err("failed to copy vma\n"); - ret = -ENOMEM; - goto fail_pages; - } - - /* extract page list from userspace mapping */ - ret = vb2_dc_get_user_pages(start, pages, n_pages, vma, dma_dir); - if (ret) { - unsigned long pfn; - if (vb2_dc_get_user_pfn(start, n_pages, vma, &pfn) == 0) { - buf->dma_addr = vb2_dc_pfn_to_dma(buf->dev, pfn); - buf->size = size; - kfree(pages); - return buf; - } - - pr_err("failed to get user pages\n"); - goto fail_vma; + /* + * Failed to convert to pages... Check the memory is physically + * contiguous and use direct mapping + */ + for (i = 1; i < n_pages; i++) + if (nums[i-1] + 1 != nums[i]) + goto fail_pfnvec; + buf->dma_addr = vb2_dc_pfn_to_dma(buf->dev, nums[0]); + goto out; } sgt = kzalloc(sizeof(*sgt), GFP_KERNEL); if (!sgt) { pr_err("failed to allocate sg table\n"); ret = -ENOMEM; - goto fail_get_user_pages; + goto fail_pfnvec; } - ret = sg_alloc_table_from_pages(sgt, pages, n_pages, + ret = sg_alloc_table_from_pages(sgt, frame_vector_pages(vec), n_pages, offset, size, GFP_KERNEL); if (ret) { pr_err("failed to initialize sg table\n"); goto fail_sgt; } - /* pages are no longer needed */ - kfree(pages); - pages = NULL; - /* * No need to sync to the device, this will happen later when the * prepare() memop is called. @@ -691,8 +561,9 @@ static void *vb2_dc_get_userptr(void *alloc_ctx, unsigned long vaddr, } buf->dma_addr = sg_dma_address(sgt->sgl); - buf->size = size; buf->dma_sgt = sgt; +out: + buf->size = size; return buf; @@ -701,23 +572,13 @@ static void *vb2_dc_get_userptr(void *alloc_ctx, unsigned long vaddr, buf->dma_dir, &attrs); fail_sgt_init: - if (!vma_is_io(buf->vma)) - vb2_dc_sgt_foreach_page(sgt, put_page); sg_free_table(sgt); fail_sgt: kfree(sgt); -fail_get_user_pages: - if (pages && !vma_is_io(buf->vma)) - while (n_pages) - put_page(pages[--n_pages]); - -fail_vma: - vb2_put_vma(buf->vma); - -fail_pages: - kfree(pages); /* kfree is NULL-proof */ +fail_pfnvec: + vb2_destroy_framevec(vec); fail_buf: kfree(buf); diff --git a/drivers/media/v4l2-core/videobuf2-dma-sg.c b/drivers/media/v4l2-core/videobuf2-dma-sg.c index 7289b81bd7b7..be7bd6535c9d 100644 --- a/drivers/media/v4l2-core/videobuf2-dma-sg.c +++ b/drivers/media/v4l2-core/videobuf2-dma-sg.c @@ -38,6 +38,7 @@ struct vb2_dma_sg_buf { struct device *dev; void *vaddr; struct page **pages; + struct frame_vector *vec; int offset; enum dma_data_direction dma_dir; struct sg_table sg_table; @@ -51,7 +52,6 @@ struct vb2_dma_sg_buf { unsigned int num_pages; atomic_t refcount; struct vb2_vmarea_handler handler; - struct vm_area_struct *vma; struct dma_buf_attachment *db_attach; }; @@ -225,25 +225,17 @@ static void vb2_dma_sg_finish(void *buf_priv) dma_sync_sg_for_cpu(buf->dev, sgt->sgl, sgt->nents, buf->dma_dir); } -static inline int vma_is_io(struct vm_area_struct *vma) -{ - return !!(vma->vm_flags & (VM_IO | VM_PFNMAP)); -} - static void *vb2_dma_sg_get_userptr(void *alloc_ctx, unsigned long vaddr, unsigned long size, enum dma_data_direction dma_dir) { struct vb2_dma_sg_conf *conf = alloc_ctx; struct vb2_dma_sg_buf *buf; - unsigned long first, last; - int num_pages_from_user; - struct vm_area_struct *vma; struct sg_table *sgt; DEFINE_DMA_ATTRS(attrs); + struct frame_vector *vec; dma_set_attr(DMA_ATTR_SKIP_CPU_SYNC, &attrs); - buf = kzalloc(sizeof *buf, GFP_KERNEL); if (!buf) return NULL; @@ -254,61 +246,19 @@ static void *vb2_dma_sg_get_userptr(void *alloc_ctx, unsigned long vaddr, buf->offset = vaddr & ~PAGE_MASK; buf->size = size; buf->dma_sgt = &buf->sg_table; + vec = vb2_create_framevec(vaddr, size, buf->dma_dir == DMA_FROM_DEVICE); + if (IS_ERR(vec)) + goto userptr_fail_pfnvec; + buf->vec = vec; - first = (vaddr & PAGE_MASK) >> PAGE_SHIFT; - last = ((vaddr + size - 1) & PAGE_MASK) >> PAGE_SHIFT; - buf->num_pages = last - first + 1; - - buf->pages = kzalloc(buf->num_pages * sizeof(struct page *), - GFP_KERNEL); - if (!buf->pages) - goto userptr_fail_alloc_pages; - - vma = find_vma(current->mm, vaddr); - if (!vma) { - dprintk(1, "no vma for address %lu\n", vaddr); - goto userptr_fail_find_vma; - } - - if (vma->vm_end < vaddr + size) { - dprintk(1, "vma at %lu is too small for %lu bytes\n", - vaddr, size); - goto userptr_fail_find_vma; - } - - buf->vma = vb2_get_vma(vma); - if (!buf->vma) { - dprintk(1, "failed to copy vma\n"); - goto userptr_fail_find_vma; - } - - if (vma_is_io(buf->vma)) { - for (num_pages_from_user = 0; - num_pages_from_user < buf->num_pages; - ++num_pages_from_user, vaddr += PAGE_SIZE) { - unsigned long pfn; - - if (follow_pfn(vma, vaddr, &pfn)) { - dprintk(1, "no page for address %lu\n", vaddr); - break; - } - buf->pages[num_pages_from_user] = pfn_to_page(pfn); - } - } else - num_pages_from_user = get_user_pages(current, current->mm, - vaddr & PAGE_MASK, - buf->num_pages, - buf->dma_dir == DMA_FROM_DEVICE, - 1, /* force */ - buf->pages, - NULL); - - if (num_pages_from_user != buf->num_pages) - goto userptr_fail_get_user_pages; + buf->pages = frame_vector_pages(vec); + if (IS_ERR(buf->pages)) + goto userptr_fail_sgtable; + buf->num_pages = frame_vector_count(vec); if (sg_alloc_table_from_pages(buf->dma_sgt, buf->pages, buf->num_pages, buf->offset, size, 0)) - goto userptr_fail_alloc_table_from_pages; + goto userptr_fail_sgtable; sgt = &buf->sg_table; /* @@ -324,17 +274,9 @@ static void *vb2_dma_sg_get_userptr(void *alloc_ctx, unsigned long vaddr, userptr_fail_map: sg_free_table(&buf->sg_table); -userptr_fail_alloc_table_from_pages: -userptr_fail_get_user_pages: - dprintk(1, "get_user_pages requested/got: %d/%d]\n", - buf->num_pages, num_pages_from_user); - if (!vma_is_io(buf->vma)) - while (--num_pages_from_user >= 0) - put_page(buf->pages[num_pages_from_user]); - vb2_put_vma(buf->vma); -userptr_fail_find_vma: - kfree(buf->pages); -userptr_fail_alloc_pages: +userptr_fail_sgtable: + vb2_destroy_framevec(vec); +userptr_fail_pfnvec: kfree(buf); return NULL; } @@ -362,11 +304,8 @@ static void vb2_dma_sg_put_userptr(void *buf_priv) while (--i >= 0) { if (buf->dma_dir == DMA_FROM_DEVICE) set_page_dirty_lock(buf->pages[i]); - if (!vma_is_io(buf->vma)) - put_page(buf->pages[i]); } - kfree(buf->pages); - vb2_put_vma(buf->vma); + vb2_destroy_framevec(buf->vec); kfree(buf); } diff --git a/drivers/media/v4l2-core/videobuf2-memops.c b/drivers/media/v4l2-core/videobuf2-memops.c index 0d49b7951f84..48c6a49c4928 100644 --- a/drivers/media/v4l2-core/videobuf2-memops.c +++ b/drivers/media/v4l2-core/videobuf2-memops.c @@ -23,118 +23,62 @@ #include /** - * vb2_get_vma() - acquire and lock the virtual memory area - * @vma: given virtual memory area + * vb2_create_framevec() - map virtual addresses to pfns + * @start: Virtual user address where we start mapping + * @length: Length of a range to map + * @write: Should we map for writing into the area * - * This function attempts to acquire an area mapped in the userspace for - * the duration of a hardware operation. The area is "locked" by performing - * the same set of operation that are done when process calls fork() and - * memory areas are duplicated. - * - * Returns a copy of a virtual memory region on success or NULL. + * This function allocates and fills in a vector with pfns corresponding to + * virtual address range passed in arguments. If pfns have corresponding pages, + * page references are also grabbed to pin pages in memory. The function + * returns pointer to the vector on success and error pointer in case of + * failure. Returned vector needs to be freed via vb2_destroy_pfnvec(). */ -struct vm_area_struct *vb2_get_vma(struct vm_area_struct *vma) +struct frame_vector *vb2_create_framevec(unsigned long start, + unsigned long length, + bool write) { - struct vm_area_struct *vma_copy; + int ret; + unsigned long first, last; + unsigned long nr; + struct frame_vector *vec; - vma_copy = kmalloc(sizeof(*vma_copy), GFP_KERNEL); - if (vma_copy == NULL) - return NULL; - - if (vma->vm_ops && vma->vm_ops->open) - vma->vm_ops->open(vma); - - if (vma->vm_file) - get_file(vma->vm_file); - - memcpy(vma_copy, vma, sizeof(*vma)); - - vma_copy->vm_mm = NULL; - vma_copy->vm_next = NULL; - vma_copy->vm_prev = NULL; - - return vma_copy; -} -EXPORT_SYMBOL_GPL(vb2_get_vma); - -/** - * vb2_put_userptr() - release a userspace virtual memory area - * @vma: virtual memory region associated with the area to be released - * - * This function releases the previously acquired memory area after a hardware - * operation. - */ -void vb2_put_vma(struct vm_area_struct *vma) -{ - if (!vma) - return; - - if (vma->vm_ops && vma->vm_ops->close) - vma->vm_ops->close(vma); - - if (vma->vm_file) - fput(vma->vm_file); - - kfree(vma); -} -EXPORT_SYMBOL_GPL(vb2_put_vma); - -/** - * vb2_get_contig_userptr() - lock physically contiguous userspace mapped memory - * @vaddr: starting virtual address of the area to be verified - * @size: size of the area - * @res_paddr: will return physical address for the given vaddr - * @res_vma: will return locked copy of struct vm_area for the given area - * - * This function will go through memory area of size @size mapped at @vaddr and - * verify that the underlying physical pages are contiguous. If they are - * contiguous the virtual memory area is locked and a @res_vma is filled with - * the copy and @res_pa set to the physical address of the buffer. - * - * Returns 0 on success. - */ -int vb2_get_contig_userptr(unsigned long vaddr, unsigned long size, - struct vm_area_struct **res_vma, dma_addr_t *res_pa) -{ - struct mm_struct *mm = current->mm; - struct vm_area_struct *vma; - unsigned long offset, start, end; - unsigned long this_pfn, prev_pfn; - dma_addr_t pa = 0; - - start = vaddr; - offset = start & ~PAGE_MASK; - end = start + size; - - vma = find_vma(mm, start); - - if (vma == NULL || vma->vm_end < end) - return -EFAULT; - - for (prev_pfn = 0; start < end; start += PAGE_SIZE) { - int ret = follow_pfn(vma, start, &this_pfn); - if (ret) - return ret; - - if (prev_pfn == 0) - pa = this_pfn << PAGE_SHIFT; - else if (this_pfn != prev_pfn + 1) - return -EFAULT; - - prev_pfn = this_pfn; + first = start >> PAGE_SHIFT; + last = (start + length - 1) >> PAGE_SHIFT; + nr = last - first + 1; + vec = frame_vector_create(nr); + if (!vec) + return ERR_PTR(-ENOMEM); + ret = get_vaddr_frames(start, nr, write, 1, vec); + if (ret < 0) + goto out_destroy; + /* We accept only complete set of PFNs */ + if (ret != nr) { + ret = -EFAULT; + goto out_release; } - - /* - * Memory is contiguous, lock vma and return to the caller - */ - *res_vma = vb2_get_vma(vma); - if (*res_vma == NULL) - return -ENOMEM; - - *res_pa = pa + offset; - return 0; + return vec; +out_release: + put_vaddr_frames(vec); +out_destroy: + frame_vector_destroy(vec); + return ERR_PTR(ret); } -EXPORT_SYMBOL_GPL(vb2_get_contig_userptr); +EXPORT_SYMBOL(vb2_create_framevec); + +/** + * vb2_destroy_framevec() - release vector of mapped pfns + * @vec: vector of pfns / pages to release + * + * This releases references to all pages in the vector @vec (if corresponding + * pfns are backed by pages) and frees the passed vector. + */ +void vb2_destroy_framevec(struct frame_vector *vec) +{ + put_vaddr_frames(vec); + frame_vector_destroy(vec); +} +EXPORT_SYMBOL(vb2_destroy_framevec); /** * vb2_common_vm_open() - increase refcount of the vma diff --git a/drivers/media/v4l2-core/videobuf2-vmalloc.c b/drivers/media/v4l2-core/videobuf2-vmalloc.c index 2fe4c27f524a..ecb8f0c7f025 100644 --- a/drivers/media/v4l2-core/videobuf2-vmalloc.c +++ b/drivers/media/v4l2-core/videobuf2-vmalloc.c @@ -23,11 +23,9 @@ struct vb2_vmalloc_buf { void *vaddr; - struct page **pages; - struct vm_area_struct *vma; + struct frame_vector *vec; enum dma_data_direction dma_dir; unsigned long size; - unsigned int n_pages; atomic_t refcount; struct vb2_vmarea_handler handler; struct dma_buf *dbuf; @@ -76,10 +74,8 @@ static void *vb2_vmalloc_get_userptr(void *alloc_ctx, unsigned long vaddr, enum dma_data_direction dma_dir) { struct vb2_vmalloc_buf *buf; - unsigned long first, last; - int n_pages, offset; - struct vm_area_struct *vma; - dma_addr_t physp; + struct frame_vector *vec; + int n_pages, offset, i; buf = kzalloc(sizeof(*buf), GFP_KERNEL); if (!buf) @@ -88,51 +84,36 @@ static void *vb2_vmalloc_get_userptr(void *alloc_ctx, unsigned long vaddr, buf->dma_dir = dma_dir; offset = vaddr & ~PAGE_MASK; buf->size = size; + vec = vb2_create_framevec(vaddr, size, dma_dir == DMA_FROM_DEVICE); + if (IS_ERR(vec)) + goto fail_pfnvec_create; + buf->vec = vec; + n_pages = frame_vector_count(vec); + if (frame_vector_to_pages(vec) < 0) { + unsigned long *nums = frame_vector_pfns(vec); - - vma = find_vma(current->mm, vaddr); - if (vma && (vma->vm_flags & VM_PFNMAP) && (vma->vm_pgoff)) { - if (vb2_get_contig_userptr(vaddr, size, &vma, &physp)) - goto fail_pages_array_alloc; - buf->vma = vma; - buf->vaddr = (__force void *)ioremap_nocache(physp, size); - if (!buf->vaddr) - goto fail_pages_array_alloc; + /* + * We cannot get page pointers for these pfns. Check memory is + * physically contiguous and use direct mapping. + */ + for (i = 1; i < n_pages; i++) + if (nums[i-1] + 1 != nums[i]) + goto fail_map; + buf->vaddr = (__force void *) + ioremap_nocache(nums[0] << PAGE_SHIFT, size); } else { - first = vaddr >> PAGE_SHIFT; - last = (vaddr + size - 1) >> PAGE_SHIFT; - buf->n_pages = last - first + 1; - buf->pages = kzalloc(buf->n_pages * sizeof(struct page *), - GFP_KERNEL); - if (!buf->pages) - goto fail_pages_array_alloc; - - /* current->mm->mmap_sem is taken by videobuf2 core */ - n_pages = get_user_pages(current, current->mm, - vaddr & PAGE_MASK, buf->n_pages, - dma_dir == DMA_FROM_DEVICE, - 1, /* force */ - buf->pages, NULL); - if (n_pages != buf->n_pages) - goto fail_get_user_pages; - - buf->vaddr = vm_map_ram(buf->pages, buf->n_pages, -1, + buf->vaddr = vm_map_ram(frame_vector_pages(vec), n_pages, -1, PAGE_KERNEL); - if (!buf->vaddr) - goto fail_get_user_pages; } + if (!buf->vaddr) + goto fail_map; buf->vaddr += offset; return buf; -fail_get_user_pages: - pr_debug("get_user_pages requested/got: %d/%d]\n", n_pages, - buf->n_pages); - while (--n_pages >= 0) - put_page(buf->pages[n_pages]); - kfree(buf->pages); - -fail_pages_array_alloc: +fail_map: + vb2_destroy_framevec(vec); +fail_pfnvec_create: kfree(buf); return NULL; @@ -143,20 +124,21 @@ static void vb2_vmalloc_put_userptr(void *buf_priv) struct vb2_vmalloc_buf *buf = buf_priv; unsigned long vaddr = (unsigned long)buf->vaddr & PAGE_MASK; unsigned int i; + struct page **pages; + unsigned int n_pages; - if (buf->pages) { + if (!buf->vec->is_pfns) { + n_pages = frame_vector_count(buf->vec); + pages = frame_vector_pages(buf->vec); if (vaddr) - vm_unmap_ram((void *)vaddr, buf->n_pages); - for (i = 0; i < buf->n_pages; ++i) { - if (buf->dma_dir == DMA_FROM_DEVICE) - set_page_dirty_lock(buf->pages[i]); - put_page(buf->pages[i]); - } - kfree(buf->pages); + vm_unmap_ram((void *)vaddr, n_pages); + if (buf->dma_dir == DMA_FROM_DEVICE) + for (i = 0; i < n_pages; i++) + set_page_dirty_lock(pages[i]); } else { - vb2_put_vma(buf->vma); iounmap((__force void __iomem *)buf->vaddr); } + vb2_destroy_framevec(buf->vec); kfree(buf); } diff --git a/include/linux/mm.h b/include/linux/mm.h index fda728e3c27d..91c08f6f0dc9 100644 --- a/include/linux/mm.h +++ b/include/linux/mm.h @@ -20,6 +20,7 @@ #include #include #include +#include struct mempolicy; struct anon_vma; @@ -1214,6 +1215,49 @@ long get_user_pages_unlocked(struct task_struct *tsk, struct mm_struct *mm, int write, int force, struct page **pages); int get_user_pages_fast(unsigned long start, int nr_pages, int write, struct page **pages); + +/* Container for pinned pfns / pages */ +struct frame_vector { + unsigned int nr_allocated; /* Number of frames we have space for */ + unsigned int nr_frames; /* Number of frames stored in ptrs array */ + bool got_ref; /* Did we pin pages by getting page ref? */ + bool is_pfns; /* Does array contain pages or pfns? */ + void *ptrs[0]; /* Array of pinned pfns / pages. Use + * pfns_vector_pages() or pfns_vector_pfns() + * for access */ +}; + +struct frame_vector *frame_vector_create(unsigned int nr_frames); +void frame_vector_destroy(struct frame_vector *vec); +int get_vaddr_frames(unsigned long start, unsigned int nr_pfns, + bool write, bool force, struct frame_vector *vec); +void put_vaddr_frames(struct frame_vector *vec); +int frame_vector_to_pages(struct frame_vector *vec); +void frame_vector_to_pfns(struct frame_vector *vec); + +static inline unsigned int frame_vector_count(struct frame_vector *vec) +{ + return vec->nr_frames; +} + +static inline struct page **frame_vector_pages(struct frame_vector *vec) +{ + if (vec->is_pfns) { + int err = frame_vector_to_pages(vec); + + if (err) + return ERR_PTR(err); + } + return (struct page **)(vec->ptrs); +} + +static inline unsigned long *frame_vector_pfns(struct frame_vector *vec) +{ + if (!vec->is_pfns) + frame_vector_to_pfns(vec); + return (unsigned long *)(vec->ptrs); +} + struct kvec; int get_kernel_pages(const struct kvec *iov, int nr_pages, int write, struct page **pages); diff --git a/include/media/videobuf2-memops.h b/include/media/videobuf2-memops.h index 9f36641a6781..6513c7ec3116 100644 --- a/include/media/videobuf2-memops.h +++ b/include/media/videobuf2-memops.h @@ -15,6 +15,7 @@ #define _MEDIA_VIDEOBUF2_MEMOPS_H #include +#include /** * struct vb2_vmarea_handler - common vma refcount tracking handler @@ -31,11 +32,9 @@ struct vb2_vmarea_handler { extern const struct vm_operations_struct vb2_common_vm_ops; -int vb2_get_contig_userptr(unsigned long vaddr, unsigned long size, - struct vm_area_struct **res_vma, dma_addr_t *res_pa); - -struct vm_area_struct *vb2_get_vma(struct vm_area_struct *vma); -void vb2_put_vma(struct vm_area_struct *vma); - +struct frame_vector *vb2_create_framevec(unsigned long start, + unsigned long length, + bool write); +void vb2_destroy_framevec(struct frame_vector *vec); #endif diff --git a/mm/Kconfig b/mm/Kconfig index 6413d027c0b2..0d9fdcd01e47 100644 --- a/mm/Kconfig +++ b/mm/Kconfig @@ -677,3 +677,6 @@ config ZONE_DEVICE mapping in an O_DIRECT operation, among other things. If FS_DAX is enabled, then say Y. + +config FRAME_VECTOR + bool diff --git a/mm/Makefile b/mm/Makefile index 56f8eed73f1a..2ed43191fc3b 100644 --- a/mm/Makefile +++ b/mm/Makefile @@ -80,3 +80,4 @@ obj-$(CONFIG_PAGE_EXTENSION) += page_ext.o obj-$(CONFIG_CMA_DEBUGFS) += cma_debug.o obj-$(CONFIG_USERFAULTFD) += userfaultfd.o obj-$(CONFIG_IDLE_PAGE_TRACKING) += page_idle.o +obj-$(CONFIG_FRAME_VECTOR) += frame_vector.o diff --git a/mm/frame_vector.c b/mm/frame_vector.c new file mode 100644 index 000000000000..cdabcb93c6a6 --- /dev/null +++ b/mm/frame_vector.c @@ -0,0 +1,230 @@ +#include +#include +#include +#include +#include +#include +#include +#include + +/* + * get_vaddr_frames() - map virtual addresses to pfns + * @start: starting user address + * @nr_frames: number of pages / pfns from start to map + * @write: whether pages will be written to by the caller + * @force: whether to force write access even if user mapping is + * readonly. See description of the same argument of + get_user_pages(). + * @vec: structure which receives pages / pfns of the addresses mapped. + * It should have space for at least nr_frames entries. + * + * This function maps virtual addresses from @start and fills @vec structure + * with page frame numbers or page pointers to corresponding pages (choice + * depends on the type of the vma underlying the virtual address). If @start + * belongs to a normal vma, the function grabs reference to each of the pages + * to pin them in memory. If @start belongs to VM_IO | VM_PFNMAP vma, we don't + * touch page structures and the caller must make sure pfns aren't reused for + * anything else while he is using them. + * + * The function returns number of pages mapped which may be less than + * @nr_frames. In particular we stop mapping if there are more vmas of + * different type underlying the specified range of virtual addresses. + * When the function isn't able to map a single page, it returns error. + * + * This function takes care of grabbing mmap_sem as necessary. + */ +int get_vaddr_frames(unsigned long start, unsigned int nr_frames, + bool write, bool force, struct frame_vector *vec) +{ + struct mm_struct *mm = current->mm; + struct vm_area_struct *vma; + int ret = 0; + int err; + int locked; + + if (nr_frames == 0) + return 0; + + if (WARN_ON_ONCE(nr_frames > vec->nr_allocated)) + nr_frames = vec->nr_allocated; + + down_read(&mm->mmap_sem); + locked = 1; + vma = find_vma_intersection(mm, start, start + 1); + if (!vma) { + ret = -EFAULT; + goto out; + } + if (!(vma->vm_flags & (VM_IO | VM_PFNMAP))) { + vec->got_ref = true; + vec->is_pfns = false; + ret = get_user_pages_locked(current, mm, start, nr_frames, + write, force, (struct page **)(vec->ptrs), &locked); + goto out; + } + + vec->got_ref = false; + vec->is_pfns = true; + do { + unsigned long *nums = frame_vector_pfns(vec); + + while (ret < nr_frames && start + PAGE_SIZE <= vma->vm_end) { + err = follow_pfn(vma, start, &nums[ret]); + if (err) { + if (ret == 0) + ret = err; + goto out; + } + start += PAGE_SIZE; + ret++; + } + /* + * We stop if we have enough pages or if VMA doesn't completely + * cover the tail page. + */ + if (ret >= nr_frames || start < vma->vm_end) + break; + vma = find_vma_intersection(mm, start, start + 1); + } while (vma && vma->vm_flags & (VM_IO | VM_PFNMAP)); +out: + if (locked) + up_read(&mm->mmap_sem); + if (!ret) + ret = -EFAULT; + if (ret > 0) + vec->nr_frames = ret; + return ret; +} +EXPORT_SYMBOL(get_vaddr_frames); + +/** + * put_vaddr_frames() - drop references to pages if get_vaddr_frames() acquired + * them + * @vec: frame vector to put + * + * Drop references to pages if get_vaddr_frames() acquired them. We also + * invalidate the frame vector so that it is prepared for the next call into + * get_vaddr_frames(). + */ +void put_vaddr_frames(struct frame_vector *vec) +{ + int i; + struct page **pages; + + if (!vec->got_ref) + goto out; + pages = frame_vector_pages(vec); + /* + * frame_vector_pages() might needed to do a conversion when + * get_vaddr_frames() got pages but vec was later converted to pfns. + * But it shouldn't really fail to convert pfns back... + */ + if (WARN_ON(IS_ERR(pages))) + goto out; + for (i = 0; i < vec->nr_frames; i++) + put_page(pages[i]); + vec->got_ref = false; +out: + vec->nr_frames = 0; +} +EXPORT_SYMBOL(put_vaddr_frames); + +/** + * frame_vector_to_pages - convert frame vector to contain page pointers + * @vec: frame vector to convert + * + * Convert @vec to contain array of page pointers. If the conversion is + * successful, return 0. Otherwise return an error. Note that we do not grab + * page references for the page structures. + */ +int frame_vector_to_pages(struct frame_vector *vec) +{ + int i; + unsigned long *nums; + struct page **pages; + + if (!vec->is_pfns) + return 0; + nums = frame_vector_pfns(vec); + for (i = 0; i < vec->nr_frames; i++) + if (!pfn_valid(nums[i])) + return -EINVAL; + pages = (struct page **)nums; + for (i = 0; i < vec->nr_frames; i++) + pages[i] = pfn_to_page(nums[i]); + vec->is_pfns = false; + return 0; +} +EXPORT_SYMBOL(frame_vector_to_pages); + +/** + * frame_vector_to_pfns - convert frame vector to contain pfns + * @vec: frame vector to convert + * + * Convert @vec to contain array of pfns. + */ +void frame_vector_to_pfns(struct frame_vector *vec) +{ + int i; + unsigned long *nums; + struct page **pages; + + if (vec->is_pfns) + return; + pages = (struct page **)(vec->ptrs); + nums = (unsigned long *)pages; + for (i = 0; i < vec->nr_frames; i++) + nums[i] = page_to_pfn(pages[i]); + vec->is_pfns = true; +} +EXPORT_SYMBOL(frame_vector_to_pfns); + +/** + * frame_vector_create() - allocate & initialize structure for pinned pfns + * @nr_frames: number of pfns slots we should reserve + * + * Allocate and initialize struct pinned_pfns to be able to hold @nr_pfns + * pfns. + */ +struct frame_vector *frame_vector_create(unsigned int nr_frames) +{ + struct frame_vector *vec; + int size = sizeof(struct frame_vector) + sizeof(void *) * nr_frames; + + if (WARN_ON_ONCE(nr_frames == 0)) + return NULL; + /* + * This is absurdly high. It's here just to avoid strange effects when + * arithmetics overflows. + */ + if (WARN_ON_ONCE(nr_frames > INT_MAX / sizeof(void *) / 2)) + return NULL; + /* + * Avoid higher order allocations, use vmalloc instead. It should + * be rare anyway. + */ + if (size <= PAGE_SIZE) + vec = kmalloc(size, GFP_KERNEL); + else + vec = vmalloc(size); + if (!vec) + return NULL; + vec->nr_allocated = nr_frames; + vec->nr_frames = 0; + return vec; +} +EXPORT_SYMBOL(frame_vector_create); + +/** + * frame_vector_destroy() - free memory allocated to carry frame vector + * @vec: Frame vector to free + * + * Free structure allocated by frame_vector_create() to carry frames. + */ +void frame_vector_destroy(struct frame_vector *vec) +{ + /* Make sure put_vaddr_frames() got called properly... */ + VM_BUG_ON(vec->nr_frames > 0); + kvfree(vec); +} +EXPORT_SYMBOL(frame_vector_destroy);