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authorLinus Torvalds <torvalds@linux-foundation.org>2015-09-11 16:42:39 -0700
committerLinus Torvalds <torvalds@linux-foundation.org>2015-09-11 16:42:39 -0700
commit06a660ada2064bbdcd09aeb8173f2ad128c71978 (patch)
tree1d0172ca83bd0a8c2186fcb41ae750420d7acb14
parentd9b44fe30fb8637b23f804eab2e7afbce129d714 (diff)
parent63540f01917c0d8b03b9813a0d6539469b163139 (diff)
downloadlinux-06a660ada2064bbdcd09aeb8173f2ad128c71978.tar.gz
Merge tag 'media/v4.3-2' of git://git.kernel.org/pub/scm/linux/kernel/git/mchehab/linux-media
Pull media updates from Mauro Carvalho Chehab: "A series of patches that move part of the code used to allocate memory from the media subsystem to the mm subsystem" [ The mm parts have been acked by VM people, and the series was apparently in -mm for a while - Linus ] * tag 'media/v4.3-2' of git://git.kernel.org/pub/scm/linux/kernel/git/mchehab/linux-media: [media] drm/exynos: Convert g2d_userptr_get_dma_addr() to use get_vaddr_frames() [media] media: vb2: Remove unused functions [media] media: vb2: Convert vb2_dc_get_userptr() to use frame vector [media] media: vb2: Convert vb2_vmalloc_get_userptr() to use frame vector [media] media: vb2: Convert vb2_dma_sg_get_userptr() to use frame vector [media] vb2: Provide helpers for mapping virtual addresses [media] media: omap_vout: Convert omap_vout_uservirt_to_phys() to use get_vaddr_pfns() [media] mm: Provide new get_vaddr_frames() helper [media] vb2: Push mmap_sem down to memops
-rw-r--r--drivers/gpu/drm/exynos/Kconfig1
-rw-r--r--drivers/gpu/drm/exynos/exynos_drm_g2d.c89
-rw-r--r--drivers/gpu/drm/exynos/exynos_drm_gem.c97
-rw-r--r--drivers/media/platform/omap/Kconfig1
-rw-r--r--drivers/media/platform/omap/omap_vout.c69
-rw-r--r--drivers/media/v4l2-core/Kconfig1
-rw-r--r--drivers/media/v4l2-core/videobuf2-core.c2
-rw-r--r--drivers/media/v4l2-core/videobuf2-dma-contig.c207
-rw-r--r--drivers/media/v4l2-core/videobuf2-dma-sg.c91
-rw-r--r--drivers/media/v4l2-core/videobuf2-memops.c148
-rw-r--r--drivers/media/v4l2-core/videobuf2-vmalloc.c90
-rw-r--r--include/linux/mm.h44
-rw-r--r--include/media/videobuf2-memops.h11
-rw-r--r--mm/Kconfig3
-rw-r--r--mm/Makefile1
-rw-r--r--mm/frame_vector.c230
16 files changed, 477 insertions, 608 deletions
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 @@ out:
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(&current->mm->mmap_sem);
- vma = find_vma(current->mm, userptr);
- if (!vma) {
- up_read(&current->mm->mmap_sem);
- DRM_ERROR("failed to get vm region.\n");
+ ret = get_vaddr_frames(start, npages, true, true, g2d_userptr->vec);
+ if (ret != npages) {
+ DRM_ERROR("failed to get user pages from userptr.\n");
+ if (ret < 0)
+ goto err_destroy_framevec;
ret = -EFAULT;
- goto err_free_pages;
+ goto err_put_framevec;
}
-
- if (vma->vm_end < userptr + size) {
- up_read(&current->mm->mmap_sem);
- DRM_ERROR("vma is too small.\n");
+ if (frame_vector_to_pages(g2d_userptr->vec) < 0) {
ret = -EFAULT;
- goto err_free_pages;
- }
-
- g2d_userptr->vma = exynos_gem_get_vma(vma);
- if (!g2d_userptr->vma) {
- up_read(&current->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(&current->mm->mmap_sem);
- DRM_ERROR("failed to get user pages from userptr.\n");
- goto err_put_vma;
+ goto err_put_framevec;
}
- up_read(&current->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 @@ err_sg_free_table:
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_vma:
- exynos_gem_put_vma(g2d_userptr->vma);
+err_put_framevec:
+ put_vaddr_frames(g2d_userptr->vec);
-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(&current->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(&current->mm->mmap_sem);
- } else {
- /* otherwise, use get_user_pages() for general userland pages */
- int res, nr_pages = 1;
- struct page *pages;
+ if (virtp >= PAGE_OFFSET) {
+ *physp = virt_to_phys((void *)virtp);
+ return 0;
+ }
- res = get_user_pages(current, current->mm, virtp, nr_pages, 1,
- 0, &pages, NULL);
- up_read(&current->mm->mmap_sem);
+ vec = frame_vector_create(1);
+ if (!vec)
+ return -ENOMEM;
- 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;
- }
+ 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 physp;
+ 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(&current->mm->mmap_sem);
ret = __qbuf_userptr(vb, b);
- up_read(&current->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 @@ fail_map_sg:
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 <media/videobuf2-memops.h>
/**
- * 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.
- */
-struct vm_area_struct *vb2_get_vma(struct vm_area_struct *vma)
-{
- struct vm_area_struct *vma_copy;
-
- 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.
+ * 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().
*/
-void vb2_put_vma(struct vm_area_struct *vma)
+struct frame_vector *vb2_create_framevec(unsigned long start,
+ unsigned long length,
+ bool write)
{
- 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 ret;
+ unsigned long first, last;
+ unsigned long nr;
+ struct frame_vector *vec;
+
+ 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;
+ }
+ return vec;
+out_release:
+ put_vaddr_frames(vec);
+out_destroy:
+ frame_vector_destroy(vec);
+ return ERR_PTR(ret);
}
-EXPORT_SYMBOL_GPL(vb2_put_vma);
+EXPORT_SYMBOL(vb2_create_framevec);
/**
- * 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.
+ * vb2_destroy_framevec() - release vector of mapped pfns
+ * @vec: vector of pfns / pages to release
*
- * Returns 0 on success.
+ * This releases references to all pages in the vector @vec (if corresponding
+ * pfns are backed by pages) and frees the passed vector.
*/
-int vb2_get_contig_userptr(unsigned long vaddr, unsigned long size,
- struct vm_area_struct **res_vma, dma_addr_t *res_pa)
+void vb2_destroy_framevec(struct frame_vector *vec)
{
- 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;
- }
-
- /*
- * 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;
+ put_vaddr_frames(vec);
+ frame_vector_destroy(vec);
}
-EXPORT_SYMBOL_GPL(vb2_get_contig_userptr);
+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;
-
-
- 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;
+ 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);
+
+ /*
+ * 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 <linux/shrinker.h>
#include <linux/resource.h>
#include <linux/page_ext.h>
+#include <linux/err.h>
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 <media/videobuf2-core.h>
+#include <linux/mm.h>
/**
* 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 <linux/kernel.h>
+#include <linux/errno.h>
+#include <linux/err.h>
+#include <linux/mm.h>
+#include <linux/slab.h>
+#include <linux/vmalloc.h>
+#include <linux/pagemap.h>
+#include <linux/sched.h>
+
+/*
+ * 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);