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Revert "media: remove the old videobuf framework"

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This reverts commit 261d98c7cf.
This commit is contained in:
CrazyCat
2024-07-29 15:36:32 +03:00
parent bc5612d2f7
commit ca94ac0541
5 changed files with 2623 additions and 0 deletions
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16
drivers/media/v4l2-core/Kconfig
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@@ -73,3 +73,19 @@ config V4L2_FWNODE
config V4L2_ASYNC config V4L2_ASYNC
tristate tristate
# Used by drivers that need Videobuf modules
config VIDEOBUF_GEN
tristate
config VIDEOBUF_DMA_SG
tristate
select VIDEOBUF_GEN
config VIDEOBUF_VMALLOC
tristate
select VIDEOBUF_GEN
config VIDEOBUF_DMA_CONTIG
tristate
select VIDEOBUF_GEN

1198
drivers/media/v4l2-core/videobuf-core.c Normal file
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File diff suppressed because it is too large Load Diff

402
drivers/media/v4l2-core/videobuf-dma-contig.c Normal file
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@@ -0,0 +1,402 @@
// SPDX-License-Identifier: GPL-2.0-only
/*
* helper functions for physically contiguous capture buffers
*
* The functions support hardware lacking scatter gather support
* (i.e. the buffers must be linear in physical memory)
*
* Copyright (c) 2008 Magnus Damm
*
* Based on videobuf-vmalloc.c,
* (c) 2007 Mauro Carvalho Chehab, <mchehab@kernel.org>
*/
#include <linux/init.h>
#include <linux/module.h>
#include <linux/mm.h>
#include <linux/pagemap.h>
#include <linux/dma-mapping.h>
#include <linux/sched.h>
#include <linux/slab.h>
#include <media/videobuf-dma-contig.h>
struct videobuf_dma_contig_memory {
u32 magic;
void *vaddr;
dma_addr_t dma_handle;
unsigned long size;
};
#define MAGIC_DC_MEM 0x0733ac61
#define MAGIC_CHECK(is, should) \
if (unlikely((is) != (should))) { \
pr_err("magic mismatch: %x expected %x\n", (is), (should)); \
BUG(); \
}
static int __videobuf_dc_alloc(struct device *dev,
struct videobuf_dma_contig_memory *mem,
unsigned long size)
{
mem->size = size;
mem->vaddr = dma_alloc_coherent(dev, mem->size, &mem->dma_handle,
GFP_KERNEL);
if (!mem->vaddr) {
dev_err(dev, "memory alloc size %ld failed\n", mem->size);
return -ENOMEM;
}
dev_dbg(dev, "dma mapped data is at %p (%ld)\n", mem->vaddr, mem->size);
return 0;
}
static void __videobuf_dc_free(struct device *dev,
struct videobuf_dma_contig_memory *mem)
{
dma_free_coherent(dev, mem->size, mem->vaddr, mem->dma_handle);
mem->vaddr = NULL;
}
static void videobuf_vm_open(struct vm_area_struct *vma)
{
struct videobuf_mapping *map = vma->vm_private_data;
dev_dbg(map->q->dev, "vm_open %p [count=%u,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;
int i;
dev_dbg(q->dev, "vm_close %p [count=%u,vma=%08lx-%08lx]\n",
map, map->count, vma->vm_start, vma->vm_end);
map->count--;
if (0 == map->count) {
struct videobuf_dma_contig_memory *mem;
dev_dbg(q->dev, "munmap %p q=%p\n", map, q);
videobuf_queue_lock(q);
/* We need first to cancel streams, before unmapping */
if (q->streaming)
videobuf_queue_cancel(q);
for (i = 0; i < VIDEO_MAX_FRAME; i++) {
if (NULL == q->bufs[i])
continue;
if (q->bufs[i]->map != map)
continue;
mem = q->bufs[i]->priv;
if (mem) {
/* This callback is called only if kernel has
allocated memory and this memory is mmapped.
In this case, memory should be freed,
in order to do memory unmap.
*/
MAGIC_CHECK(mem->magic, MAGIC_DC_MEM);
/* vfree is not atomic - can't be
called with IRQ's disabled
*/
dev_dbg(q->dev, "buf[%d] freeing %p\n",
i, mem->vaddr);
__videobuf_dc_free(q->dev, mem);
mem->vaddr = NULL;
}
q->bufs[i]->map = NULL;
q->bufs[i]->baddr = 0;
}
kfree(map);
videobuf_queue_unlock(q);
}
}
static const struct vm_operations_struct videobuf_vm_ops = {
.open = videobuf_vm_open,
.close = videobuf_vm_close,
};
/**
* videobuf_dma_contig_user_put() - reset pointer to user space buffer
* @mem: per-buffer private videobuf-dma-contig data
*
* This function resets the user space pointer
*/
static void videobuf_dma_contig_user_put(struct videobuf_dma_contig_memory *mem)
{
mem->dma_handle = 0;
mem->size = 0;
}
/**
* videobuf_dma_contig_user_get() - setup user space memory pointer
* @mem: per-buffer private videobuf-dma-contig data
* @vb: video buffer to map
*
* This function validates and sets up a pointer to user space memory.
* Only physically contiguous pfn-mapped memory is accepted.
*
* Returns 0 if successful.
*/
static int videobuf_dma_contig_user_get(struct videobuf_dma_contig_memory *mem,
struct videobuf_buffer *vb)
{
unsigned long untagged_baddr = untagged_addr(vb->baddr);
struct mm_struct *mm = current->mm;
struct vm_area_struct *vma;
unsigned long prev_pfn, this_pfn;
unsigned long pages_done, user_address;
unsigned int offset;
int ret;
offset = untagged_baddr & ~PAGE_MASK;
mem->size = PAGE_ALIGN(vb->size + offset);
ret = -EINVAL;
mmap_read_lock(mm);
vma = find_vma(mm, untagged_baddr);
if (!vma)
goto out_up;
if ((untagged_baddr + mem->size) > vma->vm_end)
goto out_up;
pages_done = 0;
prev_pfn = 0; /* kill warning */
user_address = untagged_baddr;
while (pages_done < (mem->size >> PAGE_SHIFT)) {
ret = follow_pfn(vma, user_address, &this_pfn);
if (ret)
break;
if (pages_done == 0)
mem->dma_handle = (this_pfn << PAGE_SHIFT) + offset;
else if (this_pfn != (prev_pfn + 1))
ret = -EFAULT;
if (ret)
break;
prev_pfn = this_pfn;
user_address += PAGE_SIZE;
pages_done++;
}
out_up:
mmap_read_unlock(current->mm);
return ret;
}
static struct videobuf_buffer *__videobuf_alloc(size_t size)
{
struct videobuf_dma_contig_memory *mem;
struct videobuf_buffer *vb;
vb = kzalloc(size + sizeof(*mem), GFP_KERNEL);
if (vb) {
vb->priv = ((char *)vb) + size;
mem = vb->priv;
mem->magic = MAGIC_DC_MEM;
}
return vb;
}
static void *__videobuf_to_vaddr(struct videobuf_buffer *buf)
{
struct videobuf_dma_contig_memory *mem = buf->priv;
BUG_ON(!mem);
MAGIC_CHECK(mem->magic, MAGIC_DC_MEM);
return mem->vaddr;
}
static int __videobuf_iolock(struct videobuf_queue *q,
struct videobuf_buffer *vb,
struct v4l2_framebuffer *fbuf)
{
struct videobuf_dma_contig_memory *mem = vb->priv;
BUG_ON(!mem);
MAGIC_CHECK(mem->magic, MAGIC_DC_MEM);
switch (vb->memory) {
case V4L2_MEMORY_MMAP:
dev_dbg(q->dev, "%s memory method MMAP\n", __func__);
/* All handling should be done by __videobuf_mmap_mapper() */
if (!mem->vaddr) {
dev_err(q->dev, "memory is not allocated/mmapped.\n");
return -EINVAL;
}
break;
case V4L2_MEMORY_USERPTR:
dev_dbg(q->dev, "%s memory method USERPTR\n", __func__);
/* handle pointer from user space */
if (vb->baddr)
return videobuf_dma_contig_user_get(mem, vb);
/* allocate memory for the read() method */
if (__videobuf_dc_alloc(q->dev, mem, PAGE_ALIGN(vb->size)))
return -ENOMEM;
break;
case V4L2_MEMORY_OVERLAY:
default:
dev_dbg(q->dev, "%s memory method OVERLAY/unknown\n", __func__);
return -EINVAL;
}
return 0;
}
static int __videobuf_mmap_mapper(struct videobuf_queue *q,
struct videobuf_buffer *buf,
struct vm_area_struct *vma)
{
struct videobuf_dma_contig_memory *mem;
struct videobuf_mapping *map;
int retval;
dev_dbg(q->dev, "%s\n", __func__);
/* create mapping + update buffer list */
map = kzalloc(sizeof(struct videobuf_mapping), GFP_KERNEL);
if (!map)
return -ENOMEM;
buf->map = map;
map->q = q;
buf->baddr = vma->vm_start;
mem = buf->priv;
BUG_ON(!mem);
MAGIC_CHECK(mem->magic, MAGIC_DC_MEM);
if (__videobuf_dc_alloc(q->dev, mem, PAGE_ALIGN(buf->bsize)))
goto error;
/* the "vm_pgoff" is just used in v4l2 to find the
* corresponding buffer data structure which is allocated
* earlier and it does not mean the offset from the physical
* buffer start address as usual. So set it to 0 to pass
* the sanity check in dma_mmap_coherent().
*/
vma->vm_pgoff = 0;
retval = dma_mmap_coherent(q->dev, vma, mem->vaddr, mem->dma_handle,
mem->size);
if (retval) {
dev_err(q->dev, "mmap: remap failed with error %d. ",
retval);
dma_free_coherent(q->dev, mem->size,
mem->vaddr, mem->dma_handle);
goto error;
}
vma->vm_ops = &videobuf_vm_ops;
vm_flags_set(vma, VM_DONTEXPAND);
vma->vm_private_data = map;
dev_dbg(q->dev, "mmap %p: q=%p %08lx-%08lx (%lx) pgoff %08lx buf %d\n",
map, q, vma->vm_start, vma->vm_end,
(long int)buf->bsize, vma->vm_pgoff, buf->i);
videobuf_vm_open(vma);
return 0;
error:
kfree(map);
return -ENOMEM;
}
static struct videobuf_qtype_ops qops = {
.magic = MAGIC_QTYPE_OPS,
.alloc_vb = __videobuf_alloc,
.iolock = __videobuf_iolock,
.mmap_mapper = __videobuf_mmap_mapper,
.vaddr = __videobuf_to_vaddr,
};
void videobuf_queue_dma_contig_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, &qops, ext_lock);
}
EXPORT_SYMBOL_GPL(videobuf_queue_dma_contig_init);
dma_addr_t videobuf_to_dma_contig(struct videobuf_buffer *buf)
{
struct videobuf_dma_contig_memory *mem = buf->priv;
BUG_ON(!mem);
MAGIC_CHECK(mem->magic, MAGIC_DC_MEM);
return mem->dma_handle;
}
EXPORT_SYMBOL_GPL(videobuf_to_dma_contig);
void videobuf_dma_contig_free(struct videobuf_queue *q,
struct videobuf_buffer *buf)
{
struct videobuf_dma_contig_memory *mem = buf->priv;
/* mmapped memory can't be freed here, otherwise mmapped region
would be released, while still needed. In this case, the memory
release should happen inside videobuf_vm_close().
So, it should free memory only if the memory were allocated for
read() operation.
*/
if (buf->memory != V4L2_MEMORY_USERPTR)
return;
if (!mem)
return;
MAGIC_CHECK(mem->magic, MAGIC_DC_MEM);
/* handle user space pointer case */
if (buf->baddr) {
videobuf_dma_contig_user_put(mem);
return;
}
/* read() method */
if (mem->vaddr) {
__videobuf_dc_free(q->dev, mem);
mem->vaddr = NULL;
}
}
EXPORT_SYMBOL_GPL(videobuf_dma_contig_free);
MODULE_DESCRIPTION("helper module to manage video4linux dma contig buffers");
MODULE_AUTHOR("Magnus Damm");
MODULE_LICENSE("GPL");

681
drivers/media/v4l2-core/videobuf-dma-sg.c Normal file
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@@ -0,0 +1,681 @@
// SPDX-License-Identifier: GPL-2.0-only
/*
* 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
*/
#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/pgtable.h>
#include <linux/dma-mapping.h>
#include <linux/vmalloc.h>
#include <linux/pagemap.h>
#include <linux/scatterlist.h>
#include <asm/page.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 int gup_flags = FOLL_LONGTERM;
unsigned long first, last;
int err;
dma->direction = direction;
switch (dma->direction) {
case DMA_FROM_DEVICE:
gup_flags |= FOLL_WRITE;
break;
case DMA_TO_DEVICE:
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;
dprintk(1, "init user [0x%lx+0x%lx => %lu pages]\n",
data, size, dma->nr_pages);
err = pin_user_pages(data & PAGE_MASK, dma->nr_pages, gup_flags,
dma->pages);
if (err != dma->nr_pages) {
dma->nr_pages = (err >= 0) ? err : 0;
dprintk(1, "pin_user_pages: err=%d [%lu]\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;
mmap_read_lock(current->mm);
ret = videobuf_dma_init_user_locked(dma, direction, data, size);
mmap_read_unlock(current->mm);
return ret;
}
static int videobuf_dma_init_kernel(struct videobuf_dmabuf *dma, int direction,
unsigned long nr_pages)
{
int i;
dprintk(1, "init kernel [%lu 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(%lu pages) failed\n", nr_pages);
goto out_free_pages;
}
dprintk(1, "vmalloc is at addr %p, size=%lu\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, unsigned long nr_pages)
{
dprintk(1, "init overlay [%lu 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) {
unpin_user_pages_dirty_lock(dma->pages, dma->nr_pages,
dma->direction == DMA_FROM_DEVICE);
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);
}
}
/*
* 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)
{
struct videobuf_dma_sg_memory *mem = vb->priv;
unsigned long pages;
dma_addr_t bus;
int err;
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_lock 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;
/* using shared anonymous pages */
vm_flags_mod(vma, VM_DONTEXPAND | VM_DONTDUMP, VM_IO);
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);

326
drivers/media/v4l2-core/videobuf-vmalloc.c Normal file
View File

@@ -0,0 +1,326 @@
// SPDX-License-Identifier: GPL-2.0-only
/*
* helper functions for vmalloc 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>
*/
#include <linux/init.h>
#include <linux/module.h>
#include <linux/moduleparam.h>
#include <linux/slab.h>
#include <linux/interrupt.h>
#include <linux/pgtable.h>
#include <linux/pci.h>
#include <linux/vmalloc.h>
#include <linux/pagemap.h>
#include <asm/page.h>
#include <media/videobuf-vmalloc.h>
#define MAGIC_DMABUF 0x17760309
#define MAGIC_VMAL_MEM 0x18221223
#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 vmalloc buffers");
MODULE_AUTHOR("Mauro Carvalho Chehab <mchehab@kernel.org>");
MODULE_LICENSE("GPL");
#define dprintk(level, fmt, arg...) \
if (debug >= level) \
printk(KERN_DEBUG "vbuf-vmalloc: " fmt , ## arg)
/***************************************************************************/
static void videobuf_vm_open(struct vm_area_struct *vma)
{
struct videobuf_mapping *map = vma->vm_private_data;
dprintk(2, "vm_open %p [count=%u,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;
int i;
dprintk(2, "vm_close %p [count=%u,vma=%08lx-%08lx]\n", map,
map->count, vma->vm_start, vma->vm_end);
map->count--;
if (0 == map->count) {
struct videobuf_vmalloc_memory *mem;
dprintk(1, "munmap %p q=%p\n", map, q);
videobuf_queue_lock(q);
/* We need first to cancel streams, before unmapping */
if (q->streaming)
videobuf_queue_cancel(q);
for (i = 0; i < VIDEO_MAX_FRAME; i++) {
if (NULL == q->bufs[i])
continue;
if (q->bufs[i]->map != map)
continue;
mem = q->bufs[i]->priv;
if (mem) {
/* This callback is called only if kernel has
allocated memory and this memory is mmapped.
In this case, memory should be freed,
in order to do memory unmap.
*/
MAGIC_CHECK(mem->magic, MAGIC_VMAL_MEM);
/* vfree is not atomic - can't be
called with IRQ's disabled
*/
dprintk(1, "%s: buf[%d] freeing (%p)\n",
__func__, i, mem->vaddr);
vfree(mem->vaddr);
mem->vaddr = NULL;
}
q->bufs[i]->map = NULL;
q->bufs[i]->baddr = 0;
}
kfree(map);
videobuf_queue_unlock(q);
}
return;
}
static const struct vm_operations_struct videobuf_vm_ops = {
.open = videobuf_vm_open,
.close = videobuf_vm_close,
};
/* ---------------------------------------------------------------------
* vmalloc 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_vmalloc_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_VMAL_MEM;
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 int __videobuf_iolock(struct videobuf_queue *q,
struct videobuf_buffer *vb,
struct v4l2_framebuffer *fbuf)
{
struct videobuf_vmalloc_memory *mem = vb->priv;
int pages;
BUG_ON(!mem);
MAGIC_CHECK(mem->magic, MAGIC_VMAL_MEM);
switch (vb->memory) {
case V4L2_MEMORY_MMAP:
dprintk(1, "%s memory method MMAP\n", __func__);
/* All handling should be done by __videobuf_mmap_mapper() */
if (!mem->vaddr) {
printk(KERN_ERR "memory is not allocated/mmapped.\n");
return -EINVAL;
}
break;
case V4L2_MEMORY_USERPTR:
pages = PAGE_ALIGN(vb->size);
dprintk(1, "%s memory method USERPTR\n", __func__);
if (vb->baddr) {
printk(KERN_ERR "USERPTR is currently not supported\n");
return -EINVAL;
}
/* The only USERPTR currently supported is the one needed for
* read() method.
*/
mem->vaddr = vmalloc_user(pages);
if (!mem->vaddr) {
printk(KERN_ERR "vmalloc (%d pages) failed\n", pages);
return -ENOMEM;
}
dprintk(1, "vmalloc is at addr %p (%d pages)\n",
mem->vaddr, pages);
break;
case V4L2_MEMORY_OVERLAY:
default:
dprintk(1, "%s memory method OVERLAY/unknown\n", __func__);
/* Currently, doesn't support V4L2_MEMORY_OVERLAY */
printk(KERN_ERR "Memory method currently unsupported.\n");
return -EINVAL;
}
return 0;
}
static int __videobuf_mmap_mapper(struct videobuf_queue *q,
struct videobuf_buffer *buf,
struct vm_area_struct *vma)
{
struct videobuf_vmalloc_memory *mem;
struct videobuf_mapping *map;
int retval, pages;
dprintk(1, "%s\n", __func__);
/* create mapping + update buffer list */
map = kzalloc(sizeof(struct videobuf_mapping), GFP_KERNEL);
if (NULL == map)
return -ENOMEM;
buf->map = map;
map->q = q;
buf->baddr = vma->vm_start;
mem = buf->priv;
BUG_ON(!mem);
MAGIC_CHECK(mem->magic, MAGIC_VMAL_MEM);
pages = PAGE_ALIGN(vma->vm_end - vma->vm_start);
mem->vaddr = vmalloc_user(pages);
if (!mem->vaddr) {
printk(KERN_ERR "vmalloc (%d pages) failed\n", pages);
goto error;
}
dprintk(1, "vmalloc is at addr %p (%d pages)\n", mem->vaddr, pages);
/* Try to remap memory */
retval = remap_vmalloc_range(vma, mem->vaddr, 0);
if (retval < 0) {
printk(KERN_ERR "mmap: remap failed with error %d. ", retval);
vfree(mem->vaddr);
goto error;
}
vma->vm_ops = &videobuf_vm_ops;
vm_flags_set(vma, VM_DONTEXPAND | VM_DONTDUMP);
vma->vm_private_data = map;
dprintk(1, "mmap %p: q=%p %08lx-%08lx (%lx) pgoff %08lx buf %d\n",
map, q, vma->vm_start, vma->vm_end,
(long int)buf->bsize,
vma->vm_pgoff, buf->i);
videobuf_vm_open(vma);
return 0;
error:
mem = NULL;
kfree(map);
return -ENOMEM;
}
static struct videobuf_qtype_ops qops = {
.magic = MAGIC_QTYPE_OPS,
.alloc_vb = __videobuf_alloc_vb,
.iolock = __videobuf_iolock,
.mmap_mapper = __videobuf_mmap_mapper,
.vaddr = videobuf_to_vmalloc,
};
void videobuf_queue_vmalloc_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, &qops, ext_lock);
}
EXPORT_SYMBOL_GPL(videobuf_queue_vmalloc_init);
void *videobuf_to_vmalloc(struct videobuf_buffer *buf)
{
struct videobuf_vmalloc_memory *mem = buf->priv;
BUG_ON(!mem);
MAGIC_CHECK(mem->magic, MAGIC_VMAL_MEM);
return mem->vaddr;
}
EXPORT_SYMBOL_GPL(videobuf_to_vmalloc);
void videobuf_vmalloc_free(struct videobuf_buffer *buf)
{
struct videobuf_vmalloc_memory *mem = buf->priv;
/* mmapped memory can't be freed here, otherwise mmapped region
would be released, while still needed. In this case, the memory
release should happen inside videobuf_vm_close().
So, it should free memory only if the memory were allocated for
read() operation.
*/
if ((buf->memory != V4L2_MEMORY_USERPTR) || buf->baddr)
return;
if (!mem)
return;
MAGIC_CHECK(mem->magic, MAGIC_VMAL_MEM);
vfree(mem->vaddr);
mem->vaddr = NULL;
return;
}
EXPORT_SYMBOL_GPL(videobuf_vmalloc_free);