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linux/drivers/media/v4l2-core/videobuf-dma-sg.c
Kees Cook fad953ce0b treewide: Use array_size() in vzalloc() 
The vzalloc() function has no 2-factor argument form, so multiplication
factors need to be wrapped in array_size(). This patch replaces cases of:

        vzalloc(a * b)

with:
        vzalloc(array_size(a, b))

as well as handling cases of:

        vzalloc(a * b * c)

with:

        vzalloc(array3_size(a, b, c))

This does, however, attempt to ignore constant size factors like:

        vzalloc(4 * 1024)

though any constants defined via macros get caught up in the conversion.

Any factors with a sizeof() of "unsigned char", "char", and "u8" were
dropped, since they're redundant.

The Coccinelle script used for this was:

// Fix redundant parens around sizeof().
@@
type TYPE;
expression THING, E;
@@

(
  vzalloc(
-	(sizeof(TYPE)) * E
+	sizeof(TYPE) * E
  , ...)
|
  vzalloc(
-	(sizeof(THING)) * E
+	sizeof(THING) * E
  , ...)
)

// Drop single-byte sizes and redundant parens.
@@
expression COUNT;
typedef u8;
typedef __u8;
@@

(
  vzalloc(
-	sizeof(u8) * (COUNT)
+	COUNT
  , ...)
|
  vzalloc(
-	sizeof(__u8) * (COUNT)
+	COUNT
  , ...)
|
  vzalloc(
-	sizeof(char) * (COUNT)
+	COUNT
  , ...)
|
  vzalloc(
-	sizeof(unsigned char) * (COUNT)
+	COUNT
  , ...)
|
  vzalloc(
-	sizeof(u8) * COUNT
+	COUNT
  , ...)
|
  vzalloc(
-	sizeof(__u8) * COUNT
+	COUNT
  , ...)
|
  vzalloc(
-	sizeof(char) * COUNT
+	COUNT
  , ...)
|
  vzalloc(
-	sizeof(unsigned char) * COUNT
+	COUNT
  , ...)
)

// 2-factor product with sizeof(type/expression) and identifier or constant.
@@
type TYPE;
expression THING;
identifier COUNT_ID;
constant COUNT_CONST;
@@

(
  vzalloc(
-	sizeof(TYPE) * (COUNT_ID)
+	array_size(COUNT_ID, sizeof(TYPE))
  , ...)
|
  vzalloc(
-	sizeof(TYPE) * COUNT_ID
+	array_size(COUNT_ID, sizeof(TYPE))
  , ...)
|
  vzalloc(
-	sizeof(TYPE) * (COUNT_CONST)
+	array_size(COUNT_CONST, sizeof(TYPE))
  , ...)
|
  vzalloc(
-	sizeof(TYPE) * COUNT_CONST
+	array_size(COUNT_CONST, sizeof(TYPE))
  , ...)
|
  vzalloc(
-	sizeof(THING) * (COUNT_ID)
+	array_size(COUNT_ID, sizeof(THING))
  , ...)
|
  vzalloc(
-	sizeof(THING) * COUNT_ID
+	array_size(COUNT_ID, sizeof(THING))
  , ...)
|
  vzalloc(
-	sizeof(THING) * (COUNT_CONST)
+	array_size(COUNT_CONST, sizeof(THING))
  , ...)
|
  vzalloc(
-	sizeof(THING) * COUNT_CONST
+	array_size(COUNT_CONST, sizeof(THING))
  , ...)
)

// 2-factor product, only identifiers.
@@
identifier SIZE, COUNT;
@@

  vzalloc(
-	SIZE * COUNT
+	array_size(COUNT, SIZE)
  , ...)

// 3-factor product with 1 sizeof(type) or sizeof(expression), with
// redundant parens removed.
@@
expression THING;
identifier STRIDE, COUNT;
type TYPE;
@@

(
  vzalloc(
-	sizeof(TYPE) * (COUNT) * (STRIDE)
+	array3_size(COUNT, STRIDE, sizeof(TYPE))
  , ...)
|
  vzalloc(
-	sizeof(TYPE) * (COUNT) * STRIDE
+	array3_size(COUNT, STRIDE, sizeof(TYPE))
  , ...)
|
  vzalloc(
-	sizeof(TYPE) * COUNT * (STRIDE)
+	array3_size(COUNT, STRIDE, sizeof(TYPE))
  , ...)
|
  vzalloc(
-	sizeof(TYPE) * COUNT * STRIDE
+	array3_size(COUNT, STRIDE, sizeof(TYPE))
  , ...)
|
  vzalloc(
-	sizeof(THING) * (COUNT) * (STRIDE)
+	array3_size(COUNT, STRIDE, sizeof(THING))
  , ...)
|
  vzalloc(
-	sizeof(THING) * (COUNT) * STRIDE
+	array3_size(COUNT, STRIDE, sizeof(THING))
  , ...)
|
  vzalloc(
-	sizeof(THING) * COUNT * (STRIDE)
+	array3_size(COUNT, STRIDE, sizeof(THING))
  , ...)
|
  vzalloc(
-	sizeof(THING) * COUNT * STRIDE
+	array3_size(COUNT, STRIDE, sizeof(THING))
  , ...)
)

// 3-factor product with 2 sizeof(variable), with redundant parens removed.
@@
expression THING1, THING2;
identifier COUNT;
type TYPE1, TYPE2;
@@

(
  vzalloc(
-	sizeof(TYPE1) * sizeof(TYPE2) * COUNT
+	array3_size(COUNT, sizeof(TYPE1), sizeof(TYPE2))
  , ...)
|
  vzalloc(
-	sizeof(TYPE1) * sizeof(THING2) * (COUNT)
+	array3_size(COUNT, sizeof(TYPE1), sizeof(TYPE2))
  , ...)
|
  vzalloc(
-	sizeof(THING1) * sizeof(THING2) * COUNT
+	array3_size(COUNT, sizeof(THING1), sizeof(THING2))
  , ...)
|
  vzalloc(
-	sizeof(THING1) * sizeof(THING2) * (COUNT)
+	array3_size(COUNT, sizeof(THING1), sizeof(THING2))
  , ...)
|
  vzalloc(
-	sizeof(TYPE1) * sizeof(THING2) * COUNT
+	array3_size(COUNT, sizeof(TYPE1), sizeof(THING2))
  , ...)
|
  vzalloc(
-	sizeof(TYPE1) * sizeof(THING2) * (COUNT)
+	array3_size(COUNT, sizeof(TYPE1), sizeof(THING2))
  , ...)
)

// 3-factor product, only identifiers, with redundant parens removed.
@@
identifier STRIDE, SIZE, COUNT;
@@

(
  vzalloc(
-	(COUNT) * STRIDE * SIZE
+	array3_size(COUNT, STRIDE, SIZE)
  , ...)
|
  vzalloc(
-	COUNT * (STRIDE) * SIZE
+	array3_size(COUNT, STRIDE, SIZE)
  , ...)
|
  vzalloc(
-	COUNT * STRIDE * (SIZE)
+	array3_size(COUNT, STRIDE, SIZE)
  , ...)
|
  vzalloc(
-	(COUNT) * (STRIDE) * SIZE
+	array3_size(COUNT, STRIDE, SIZE)
  , ...)
|
  vzalloc(
-	COUNT * (STRIDE) * (SIZE)
+	array3_size(COUNT, STRIDE, SIZE)
  , ...)
|
  vzalloc(
-	(COUNT) * STRIDE * (SIZE)
+	array3_size(COUNT, STRIDE, SIZE)
  , ...)
|
  vzalloc(
-	(COUNT) * (STRIDE) * (SIZE)
+	array3_size(COUNT, STRIDE, SIZE)
  , ...)
|
  vzalloc(
-	COUNT * STRIDE * SIZE
+	array3_size(COUNT, STRIDE, SIZE)
  , ...)
)

// Any remaining multi-factor products, first at least 3-factor products
// when they're not all constants...
@@
expression E1, E2, E3;
constant C1, C2, C3;
@@

(
  vzalloc(C1 * C2 * C3, ...)
|
  vzalloc(
-	E1 * E2 * E3
+	array3_size(E1, E2, E3)
  , ...)
)

// And then all remaining 2 factors products when they're not all constants.
@@
expression E1, E2;
constant C1, C2;
@@

(
  vzalloc(C1 * C2, ...)
|
  vzalloc(
-	E1 * E2
+	array_size(E1, E2)
  , ...)
)

Signed-off-by: Kees Cook <keescook@chromium.org>
2018-06-12 16:19:22 -07:00

688 lines
16 KiB
C
Raw Blame History

/*
* helper functions for SG DMA video4linux capture buffers
*
* The functions expect the hardware being able to scatter gather
* (i.e. the buffers are not linear in physical memory, but fragmented
* into PAGE_SIZE chunks). They also assume the driver does not need
* to touch the video data.
*
* (c) 2007 Mauro Carvalho Chehab, <mchehab@kernel.org>
*
* Highly based on video-buf written originally by:
* (c) 2001,02 Gerd Knorr <kraxel@bytesex.org>
* (c) 2006 Mauro Carvalho Chehab, <mchehab@kernel.org>
* (c) 2006 Ted Walther and John Sokol
*
* This program is free software; you can redistribute it and/or modify
* it under the terms of the GNU General Public License as published by
* the Free Software Foundation; either version 2
*/
#include <linux/init.h>
#include <linux/module.h>
#include <linux/moduleparam.h>
#include <linux/sched/mm.h>
#include <linux/slab.h>
#include <linux/interrupt.h>
#include <linux/dma-mapping.h>
#include <linux/vmalloc.h>
#include <linux/pagemap.h>
#include <linux/scatterlist.h>
#include <asm/page.h>
#include <asm/pgtable.h>
#include <media/videobuf-dma-sg.h>
#define MAGIC_DMABUF 0x19721112
#define MAGIC_SG_MEM 0x17890714
#define MAGIC_CHECK(is, should) \
if (unlikely((is) != (should))) { \
printk(KERN_ERR "magic mismatch: %x (expected %x)\n", \
is, should); \
BUG(); \
}
static int debug;
module_param(debug, int, 0644);
MODULE_DESCRIPTION("helper module to manage video4linux dma sg buffers");
MODULE_AUTHOR("Mauro Carvalho Chehab <mchehab@kernel.org>");
MODULE_LICENSE("GPL");
#define dprintk(level, fmt, arg...) \
if (debug >= level) \
printk(KERN_DEBUG "vbuf-sg: " fmt , ## arg)
/* --------------------------------------------------------------------- */
/*
* Return a scatterlist for some page-aligned vmalloc()'ed memory
* block (NULL on errors). Memory for the scatterlist is allocated
* using kmalloc. The caller must free the memory.
*/
static struct scatterlist *videobuf_vmalloc_to_sg(unsigned char *virt,
int nr_pages)
{
struct scatterlist *sglist;
struct page *pg;
int i;
sglist = vzalloc(array_size(nr_pages, sizeof(*sglist)));
if (NULL == sglist)
return NULL;
sg_init_table(sglist, nr_pages);
for (i = 0; i < nr_pages; i++, virt += PAGE_SIZE) {
pg = vmalloc_to_page(virt);
if (NULL == pg)
goto err;
BUG_ON(PageHighMem(pg));
sg_set_page(&sglist[i], pg, PAGE_SIZE, 0);
}
return sglist;
err:
vfree(sglist);
return NULL;
}
/*
* Return a scatterlist for a an array of userpages (NULL on errors).
* Memory for the scatterlist is allocated using kmalloc. The caller
* must free the memory.
*/
static struct scatterlist *videobuf_pages_to_sg(struct page **pages,
int nr_pages, int offset, size_t size)
{
struct scatterlist *sglist;
int i;
if (NULL == pages[0])
return NULL;
sglist = vmalloc(array_size(nr_pages, sizeof(*sglist)));
if (NULL == sglist)
return NULL;
sg_init_table(sglist, nr_pages);
if (PageHighMem(pages[0]))
/* DMA to highmem pages might not work */
goto highmem;
sg_set_page(&sglist[0], pages[0],
min_t(size_t, PAGE_SIZE - offset, size), offset);
size -= min_t(size_t, PAGE_SIZE - offset, size);
for (i = 1; i < nr_pages; i++) {
if (NULL == pages[i])
goto nopage;
if (PageHighMem(pages[i]))
goto highmem;
sg_set_page(&sglist[i], pages[i], min_t(size_t, PAGE_SIZE, size), 0);
size -= min_t(size_t, PAGE_SIZE, size);
}
return sglist;
nopage:
dprintk(2, "sgl: oops - no page\n");
vfree(sglist);
return NULL;
highmem:
dprintk(2, "sgl: oops - highmem page\n");
vfree(sglist);
return NULL;
}
/* --------------------------------------------------------------------- */
struct videobuf_dmabuf *videobuf_to_dma(struct videobuf_buffer *buf)
{
struct videobuf_dma_sg_memory *mem = buf->priv;
BUG_ON(!mem);
MAGIC_CHECK(mem->magic, MAGIC_SG_MEM);
return &mem->dma;
}
EXPORT_SYMBOL_GPL(videobuf_to_dma);
static void videobuf_dma_init(struct videobuf_dmabuf *dma)
{
memset(dma, 0, sizeof(*dma));
dma->magic = MAGIC_DMABUF;
}
static int videobuf_dma_init_user_locked(struct videobuf_dmabuf *dma,
int direction, unsigned long data, unsigned long size)
{
unsigned long first, last;
int err, rw = 0;
unsigned int flags = FOLL_FORCE;
dma->direction = direction;
switch (dma->direction) {
case DMA_FROM_DEVICE:
rw = READ;
break;
case DMA_TO_DEVICE:
rw = WRITE;
break;
default:
BUG();
}
first = (data & PAGE_MASK) >> PAGE_SHIFT;
last = ((data+size-1) & PAGE_MASK) >> PAGE_SHIFT;
dma->offset = data & ~PAGE_MASK;
dma->size = size;
dma->nr_pages = last-first+1;
dma->pages = kmalloc_array(dma->nr_pages, sizeof(struct page *),
GFP_KERNEL);
if (NULL == dma->pages)
return -ENOMEM;
if (rw == READ)
flags |= FOLL_WRITE;
dprintk(1, "init user [0x%lx+0x%lx => %d pages]\n",
data, size, dma->nr_pages);
err = get_user_pages_longterm(data & PAGE_MASK, dma->nr_pages,
flags, dma->pages, NULL);
if (err != dma->nr_pages) {
dma->nr_pages = (err >= 0) ? err : 0;
dprintk(1, "get_user_pages_longterm: err=%d [%d]\n", err,
dma->nr_pages);
return err < 0 ? err : -EINVAL;
}
return 0;
}
static int videobuf_dma_init_user(struct videobuf_dmabuf *dma, int direction,
unsigned long data, unsigned long size)
{
int ret;
down_read(&current->mm->mmap_sem);
ret = videobuf_dma_init_user_locked(dma, direction, data, size);
up_read(&current->mm->mmap_sem);
return ret;
}
static int videobuf_dma_init_kernel(struct videobuf_dmabuf *dma, int direction,
int nr_pages)
{
int i;
dprintk(1, "init kernel [%d pages]\n", nr_pages);
dma->direction = direction;
dma->vaddr_pages = kcalloc(nr_pages, sizeof(*dma->vaddr_pages),
GFP_KERNEL);
if (!dma->vaddr_pages)
return -ENOMEM;
dma->dma_addr = kcalloc(nr_pages, sizeof(*dma->dma_addr), GFP_KERNEL);
if (!dma->dma_addr) {
kfree(dma->vaddr_pages);
return -ENOMEM;
}
for (i = 0; i < nr_pages; i++) {
void *addr;
addr = dma_alloc_coherent(dma->dev, PAGE_SIZE,
&(dma->dma_addr[i]), GFP_KERNEL);
if (addr == NULL)
goto out_free_pages;
dma->vaddr_pages[i] = virt_to_page(addr);
}
dma->vaddr = vmap(dma->vaddr_pages, nr_pages, VM_MAP | VM_IOREMAP,
PAGE_KERNEL);
if (NULL == dma->vaddr) {
dprintk(1, "vmalloc_32(%d pages) failed\n", nr_pages);
goto out_free_pages;
}
dprintk(1, "vmalloc is at addr %p, size=%d\n",
dma->vaddr, nr_pages << PAGE_SHIFT);
memset(dma->vaddr, 0, nr_pages << PAGE_SHIFT);
dma->nr_pages = nr_pages;
return 0;
out_free_pages:
while (i > 0) {
void *addr;
i--;
addr = page_address(dma->vaddr_pages[i]);
dma_free_coherent(dma->dev, PAGE_SIZE, addr, dma->dma_addr[i]);
}
kfree(dma->dma_addr);
dma->dma_addr = NULL;
kfree(dma->vaddr_pages);
dma->vaddr_pages = NULL;
return -ENOMEM;
}
static int videobuf_dma_init_overlay(struct videobuf_dmabuf *dma, int direction,
dma_addr_t addr, int nr_pages)
{
dprintk(1, "init overlay [%d pages @ bus 0x%lx]\n",
nr_pages, (unsigned long)addr);
dma->direction = direction;
if (0 == addr)
return -EINVAL;
dma->bus_addr = addr;
dma->nr_pages = nr_pages;
return 0;
}
static int videobuf_dma_map(struct device *dev, struct videobuf_dmabuf *dma)
{
MAGIC_CHECK(dma->magic, MAGIC_DMABUF);
BUG_ON(0 == dma->nr_pages);
if (dma->pages) {
dma->sglist = videobuf_pages_to_sg(dma->pages, dma->nr_pages,
dma->offset, dma->size);
}
if (dma->vaddr) {
dma->sglist = videobuf_vmalloc_to_sg(dma->vaddr,
dma->nr_pages);
}
if (dma->bus_addr) {
dma->sglist = vmalloc(sizeof(*dma->sglist));
if (NULL != dma->sglist) {
dma->sglen = 1;
sg_dma_address(&dma->sglist[0]) = dma->bus_addr
& PAGE_MASK;
dma->sglist[0].offset = dma->bus_addr & ~PAGE_MASK;
sg_dma_len(&dma->sglist[0]) = dma->nr_pages * PAGE_SIZE;
}
}
if (NULL == dma->sglist) {
dprintk(1, "scatterlist is NULL\n");
return -ENOMEM;
}
if (!dma->bus_addr) {
dma->sglen = dma_map_sg(dev, dma->sglist,
dma->nr_pages, dma->direction);
if (0 == dma->sglen) {
printk(KERN_WARNING
"%s: videobuf_map_sg failed\n", __func__);
vfree(dma->sglist);
dma->sglist = NULL;
dma->sglen = 0;
return -ENOMEM;
}
}
return 0;
}
int videobuf_dma_unmap(struct device *dev, struct videobuf_dmabuf *dma)
{
MAGIC_CHECK(dma->magic, MAGIC_DMABUF);
if (!dma->sglen)
return 0;
dma_unmap_sg(dev, dma->sglist, dma->nr_pages, dma->direction);
vfree(dma->sglist);
dma->sglist = NULL;
dma->sglen = 0;
return 0;
}
EXPORT_SYMBOL_GPL(videobuf_dma_unmap);
int videobuf_dma_free(struct videobuf_dmabuf *dma)
{
int i;
MAGIC_CHECK(dma->magic, MAGIC_DMABUF);
BUG_ON(dma->sglen);
if (dma->pages) {
for (i = 0; i < dma->nr_pages; i++)
put_page(dma->pages[i]);
kfree(dma->pages);
dma->pages = NULL;
}
if (dma->dma_addr) {
for (i = 0; i < dma->nr_pages; i++) {
void *addr;
addr = page_address(dma->vaddr_pages[i]);
dma_free_coherent(dma->dev, PAGE_SIZE, addr,
dma->dma_addr[i]);
}
kfree(dma->dma_addr);
dma->dma_addr = NULL;
kfree(dma->vaddr_pages);
dma->vaddr_pages = NULL;
vunmap(dma->vaddr);
dma->vaddr = NULL;
}
if (dma->bus_addr)
dma->bus_addr = 0;
dma->direction = DMA_NONE;
return 0;
}
EXPORT_SYMBOL_GPL(videobuf_dma_free);
/* --------------------------------------------------------------------- */
static void videobuf_vm_open(struct vm_area_struct *vma)
{
struct videobuf_mapping *map = vma->vm_private_data;
dprintk(2, "vm_open %p [count=%d,vma=%08lx-%08lx]\n", map,
map->count, vma->vm_start, vma->vm_end);
map->count++;
}
static void videobuf_vm_close(struct vm_area_struct *vma)
{
struct videobuf_mapping *map = vma->vm_private_data;
struct videobuf_queue *q = map->q;
struct videobuf_dma_sg_memory *mem;
int i;
dprintk(2, "vm_close %p [count=%d,vma=%08lx-%08lx]\n", map,
map->count, vma->vm_start, vma->vm_end);
map->count--;
if (0 == map->count) {
dprintk(1, "munmap %p q=%p\n", map, q);
videobuf_queue_lock(q);
for (i = 0; i < VIDEO_MAX_FRAME; i++) {
if (NULL == q->bufs[i])
continue;
mem = q->bufs[i]->priv;
if (!mem)
continue;
MAGIC_CHECK(mem->magic, MAGIC_SG_MEM);
if (q->bufs[i]->map != map)
continue;
q->bufs[i]->map = NULL;
q->bufs[i]->baddr = 0;
q->ops->buf_release(q, q->bufs[i]);
}
videobuf_queue_unlock(q);
kfree(map);
}
return;
}
/*
* Get a anonymous page for the mapping. Make sure we can DMA to that
* memory location with 32bit PCI devices (i.e. don't use highmem for
* now ...). Bounce buffers don't work very well for the data rates
* video capture has.
*/
static vm_fault_t videobuf_vm_fault(struct vm_fault *vmf)
{
struct vm_area_struct *vma = vmf->vma;
struct page *page;
dprintk(3, "fault: fault @ %08lx [vma %08lx-%08lx]\n",
vmf->address, vma->vm_start, vma->vm_end);
page = alloc_page(GFP_USER | __GFP_DMA32);
if (!page)
return VM_FAULT_OOM;
clear_user_highpage(page, vmf->address);
vmf->page = page;
return 0;
}
static const struct vm_operations_struct videobuf_vm_ops = {
.open = videobuf_vm_open,
.close = videobuf_vm_close,
.fault = videobuf_vm_fault,
};
/* ---------------------------------------------------------------------
* SG handlers for the generic methods
*/
/* Allocated area consists on 3 parts:
struct video_buffer
struct <driver>_buffer (cx88_buffer, saa7134_buf, ...)
struct videobuf_dma_sg_memory
*/
static struct videobuf_buffer *__videobuf_alloc_vb(size_t size)
{
struct videobuf_dma_sg_memory *mem;
struct videobuf_buffer *vb;
vb = kzalloc(size + sizeof(*mem), GFP_KERNEL);
if (!vb)
return vb;
mem = vb->priv = ((char *)vb) + size;
mem->magic = MAGIC_SG_MEM;
videobuf_dma_init(&mem->dma);
dprintk(1, "%s: allocated at %p(%ld+%ld) & %p(%ld)\n",
__func__, vb, (long)sizeof(*vb), (long)size - sizeof(*vb),
mem, (long)sizeof(*mem));
return vb;
}
static void *__videobuf_to_vaddr(struct videobuf_buffer *buf)
{
struct videobuf_dma_sg_memory *mem = buf->priv;
BUG_ON(!mem);
MAGIC_CHECK(mem->magic, MAGIC_SG_MEM);
return mem->dma.vaddr;
}
static int __videobuf_iolock(struct videobuf_queue *q,
struct videobuf_buffer *vb,
struct v4l2_framebuffer *fbuf)
{
int err, pages;
dma_addr_t bus;
struct videobuf_dma_sg_memory *mem = vb->priv;
BUG_ON(!mem);
MAGIC_CHECK(mem->magic, MAGIC_SG_MEM);
if (!mem->dma.dev)
mem->dma.dev = q->dev;
else
WARN_ON(mem->dma.dev != q->dev);
switch (vb->memory) {
case V4L2_MEMORY_MMAP:
case V4L2_MEMORY_USERPTR:
if (0 == vb->baddr) {
/* no userspace addr -- kernel bounce buffer */
pages = PAGE_ALIGN(vb->size) >> PAGE_SHIFT;
err = videobuf_dma_init_kernel(&mem->dma,
DMA_FROM_DEVICE,
pages);
if (0 != err)
return err;
} else if (vb->memory == V4L2_MEMORY_USERPTR) {
/* dma directly to userspace */
err = videobuf_dma_init_user(&mem->dma,
DMA_FROM_DEVICE,
vb->baddr, vb->bsize);
if (0 != err)
return err;
} else {
/* NOTE: HACK: videobuf_iolock on V4L2_MEMORY_MMAP
buffers can only be called from videobuf_qbuf
we take current->mm->mmap_sem there, to prevent
locking inversion, so don't take it here */
err = videobuf_dma_init_user_locked(&mem->dma,
DMA_FROM_DEVICE,
vb->baddr, vb->bsize);
if (0 != err)
return err;
}
break;
case V4L2_MEMORY_OVERLAY:
if (NULL == fbuf)
return -EINVAL;
/* FIXME: need sanity checks for vb->boff */
/*
* Using a double cast to avoid compiler warnings when
* building for PAE. Compiler doesn't like direct casting
* of a 32 bit ptr to 64 bit integer.
*/
bus = (dma_addr_t)(unsigned long)fbuf->base + vb->boff;
pages = PAGE_ALIGN(vb->size) >> PAGE_SHIFT;
err = videobuf_dma_init_overlay(&mem->dma, DMA_FROM_DEVICE,
bus, pages);
if (0 != err)
return err;
break;
default:
BUG();
}
err = videobuf_dma_map(q->dev, &mem->dma);
if (0 != err)
return err;
return 0;
}
static int __videobuf_sync(struct videobuf_queue *q,
struct videobuf_buffer *buf)
{
struct videobuf_dma_sg_memory *mem = buf->priv;
BUG_ON(!mem || !mem->dma.sglen);
MAGIC_CHECK(mem->magic, MAGIC_SG_MEM);
MAGIC_CHECK(mem->dma.magic, MAGIC_DMABUF);
dma_sync_sg_for_cpu(q->dev, mem->dma.sglist,
mem->dma.nr_pages, mem->dma.direction);
return 0;
}
static int __videobuf_mmap_mapper(struct videobuf_queue *q,
struct videobuf_buffer *buf,
struct vm_area_struct *vma)
{
struct videobuf_dma_sg_memory *mem = buf->priv;
struct videobuf_mapping *map;
unsigned int first, last, size = 0, i;
int retval;
retval = -EINVAL;
BUG_ON(!mem);
MAGIC_CHECK(mem->magic, MAGIC_SG_MEM);
/* look for first buffer to map */
for (first = 0; first < VIDEO_MAX_FRAME; first++) {
if (buf == q->bufs[first]) {
size = PAGE_ALIGN(q->bufs[first]->bsize);
break;
}
}
/* paranoia, should never happen since buf is always valid. */
if (!size) {
dprintk(1, "mmap app bug: offset invalid [offset=0x%lx]\n",
(vma->vm_pgoff << PAGE_SHIFT));
goto done;
}
last = first;
/* create mapping + update buffer list */
retval = -ENOMEM;
map = kmalloc(sizeof(struct videobuf_mapping), GFP_KERNEL);
if (NULL == map)
goto done;
size = 0;
for (i = first; i <= last; i++) {
if (NULL == q->bufs[i])
continue;
q->bufs[i]->map = map;
q->bufs[i]->baddr = vma->vm_start + size;
size += PAGE_ALIGN(q->bufs[i]->bsize);
}
map->count = 1;
map->q = q;
vma->vm_ops = &videobuf_vm_ops;
vma->vm_flags |= VM_DONTEXPAND | VM_DONTDUMP;
vma->vm_flags &= ~VM_IO; /* using shared anonymous pages */
vma->vm_private_data = map;
dprintk(1, "mmap %p: q=%p %08lx-%08lx pgoff %08lx bufs %d-%d\n",
map, q, vma->vm_start, vma->vm_end, vma->vm_pgoff, first, last);
retval = 0;
done:
return retval;
}
static struct videobuf_qtype_ops sg_ops = {
.magic = MAGIC_QTYPE_OPS,
.alloc_vb = __videobuf_alloc_vb,
.iolock = __videobuf_iolock,
.sync = __videobuf_sync,
.mmap_mapper = __videobuf_mmap_mapper,
.vaddr = __videobuf_to_vaddr,
};
void *videobuf_sg_alloc(size_t size)
{
struct videobuf_queue q;
/* Required to make generic handler to call __videobuf_alloc */
q.int_ops = &sg_ops;
q.msize = size;
return videobuf_alloc_vb(&q);
}
EXPORT_SYMBOL_GPL(videobuf_sg_alloc);
void videobuf_queue_sg_init(struct videobuf_queue *q,
const struct videobuf_queue_ops *ops,
struct device *dev,
spinlock_t *irqlock,
enum v4l2_buf_type type,
enum v4l2_field field,
unsigned int msize,
void *priv,
struct mutex *ext_lock)
{
videobuf_queue_core_init(q, ops, dev, irqlock, type, field, msize,
priv, &sg_ops, ext_lock);
}
EXPORT_SYMBOL_GPL(videobuf_queue_sg_init);
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