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media updates for v4.3-rc1

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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
This commit is contained in:
Linus Torvalds 2015-09-11 16:42:39 -07:00
commit 06a660ada2
16 changed files with 484 additions and 615 deletions
Show Stats Download Patch File Download Diff File Expand all files Collapse all files

1
drivers/gpu/drm/exynos/Kconfig
View File

@ -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.

93
drivers/gpu/drm/exynos/exynos_drm_g2d.c
View File

@ -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 = -EFAULT;
goto err_free_pages;
}
if (vma->vm_end < userptr + size) {
up_read(&current->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(&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);
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(&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_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);

97
drivers/gpu/drm/exynos/exynos_drm_gem.c
View File

@ -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)

1
drivers/media/platform/omap/Kconfig
View File

@ -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.

73
drivers/media/platform/omap/omap_vout.c
View File

@ -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;
res = get_user_pages(current, current->mm, virtp, nr_pages, 1,
0, &pages, NULL);
up_read(&current->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);
}
}
/*

1
drivers/media/v4l2-core/Kconfig
View File

@ -84,6 +84,7 @@ config VIDEOBUF2_CORE
config VIDEOBUF2_MEMOPS
tristate
select FRAME_VECTOR
config VIDEOBUF2_DMA_CONTIG
tristate

2
drivers/media/v4l2-core/videobuf2-core.c
View File

@ -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);

207
drivers/media/v4l2-core/videobuf2-dma-contig.c
View File

@ -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);

91
drivers/media/v4l2-core/videobuf2-dma-sg.c
View File

@ -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);
}

156
drivers/media/v4l2-core/videobuf2-memops.c
View File

@ -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.
* 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

88
drivers/media/v4l2-core/videobuf2-vmalloc.c
View File

@ -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);
}

44
include/linux/mm.h
View File

@ -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);

11
include/media/videobuf2-memops.h
View File

@ -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

3
mm/Kconfig
View File

@ -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

1
mm/Makefile
View File

@ -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

230
mm/frame_vector.c Normal file
View File

@ -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);