![Markus Elfring](/assets/img/avatar_default.png)
The vb2_put_vma() function tests whether its argument is NULL and then returns immediately. Thus the test around the call is not needed. This issue was detected by using the Coccinelle software. Signed-off-by: Markus Elfring <elfring@users.sourceforge.net> Acked-by: Marek Szyprowski <m.szyprowski@samsung.com> Signed-off-by: Hans Verkuil <hans.verkuil@cisco.com> Signed-off-by: Mauro Carvalho Chehab <mchehab@osg.samsung.com>
454 lines
10 KiB
C
454 lines
10 KiB
C
/*
|
|
* videobuf2-vmalloc.c - vmalloc memory allocator for videobuf2
|
|
*
|
|
* Copyright (C) 2010 Samsung Electronics
|
|
*
|
|
* Author: Pawel Osciak <pawel@osciak.com>
|
|
*
|
|
* 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.
|
|
*/
|
|
|
|
#include <linux/io.h>
|
|
#include <linux/module.h>
|
|
#include <linux/mm.h>
|
|
#include <linux/sched.h>
|
|
#include <linux/slab.h>
|
|
#include <linux/vmalloc.h>
|
|
|
|
#include <media/videobuf2-core.h>
|
|
#include <media/videobuf2-vmalloc.h>
|
|
#include <media/videobuf2-memops.h>
|
|
|
|
struct vb2_vmalloc_buf {
|
|
void *vaddr;
|
|
struct page **pages;
|
|
struct vm_area_struct *vma;
|
|
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;
|
|
};
|
|
|
|
static void vb2_vmalloc_put(void *buf_priv);
|
|
|
|
static void *vb2_vmalloc_alloc(void *alloc_ctx, unsigned long size,
|
|
enum dma_data_direction dma_dir, gfp_t gfp_flags)
|
|
{
|
|
struct vb2_vmalloc_buf *buf;
|
|
|
|
buf = kzalloc(sizeof(*buf), GFP_KERNEL | gfp_flags);
|
|
if (!buf)
|
|
return NULL;
|
|
|
|
buf->size = size;
|
|
buf->vaddr = vmalloc_user(buf->size);
|
|
buf->dma_dir = dma_dir;
|
|
buf->handler.refcount = &buf->refcount;
|
|
buf->handler.put = vb2_vmalloc_put;
|
|
buf->handler.arg = buf;
|
|
|
|
if (!buf->vaddr) {
|
|
pr_debug("vmalloc of size %ld failed\n", buf->size);
|
|
kfree(buf);
|
|
return NULL;
|
|
}
|
|
|
|
atomic_inc(&buf->refcount);
|
|
return buf;
|
|
}
|
|
|
|
static void vb2_vmalloc_put(void *buf_priv)
|
|
{
|
|
struct vb2_vmalloc_buf *buf = buf_priv;
|
|
|
|
if (atomic_dec_and_test(&buf->refcount)) {
|
|
vfree(buf->vaddr);
|
|
kfree(buf);
|
|
}
|
|
}
|
|
|
|
static void *vb2_vmalloc_get_userptr(void *alloc_ctx, unsigned long vaddr,
|
|
unsigned long size,
|
|
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;
|
|
|
|
buf = kzalloc(sizeof(*buf), GFP_KERNEL);
|
|
if (!buf)
|
|
return NULL;
|
|
|
|
buf->dma_dir = dma_dir;
|
|
offset = vaddr & ~PAGE_MASK;
|
|
buf->size = size;
|
|
|
|
|
|
vma = find_vma(current->mm, vaddr);
|
|
if (vma && (vma->vm_flags & VM_PFNMAP) && (vma->vm_pgoff)) {
|
|
if (vb2_get_contig_userptr(vaddr, size, &vma, &physp))
|
|
goto fail_pages_array_alloc;
|
|
buf->vma = vma;
|
|
buf->vaddr = ioremap_nocache(physp, size);
|
|
if (!buf->vaddr)
|
|
goto fail_pages_array_alloc;
|
|
} 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,
|
|
PAGE_KERNEL);
|
|
if (!buf->vaddr)
|
|
goto fail_get_user_pages;
|
|
}
|
|
|
|
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:
|
|
kfree(buf);
|
|
|
|
return NULL;
|
|
}
|
|
|
|
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;
|
|
|
|
if (buf->pages) {
|
|
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);
|
|
} else {
|
|
vb2_put_vma(buf->vma);
|
|
iounmap(buf->vaddr);
|
|
}
|
|
kfree(buf);
|
|
}
|
|
|
|
static void *vb2_vmalloc_vaddr(void *buf_priv)
|
|
{
|
|
struct vb2_vmalloc_buf *buf = buf_priv;
|
|
|
|
if (!buf->vaddr) {
|
|
pr_err("Address of an unallocated plane requested "
|
|
"or cannot map user pointer\n");
|
|
return NULL;
|
|
}
|
|
|
|
return buf->vaddr;
|
|
}
|
|
|
|
static unsigned int vb2_vmalloc_num_users(void *buf_priv)
|
|
{
|
|
struct vb2_vmalloc_buf *buf = buf_priv;
|
|
return atomic_read(&buf->refcount);
|
|
}
|
|
|
|
static int vb2_vmalloc_mmap(void *buf_priv, struct vm_area_struct *vma)
|
|
{
|
|
struct vb2_vmalloc_buf *buf = buf_priv;
|
|
int ret;
|
|
|
|
if (!buf) {
|
|
pr_err("No memory to map\n");
|
|
return -EINVAL;
|
|
}
|
|
|
|
ret = remap_vmalloc_range(vma, buf->vaddr, 0);
|
|
if (ret) {
|
|
pr_err("Remapping vmalloc memory, error: %d\n", ret);
|
|
return ret;
|
|
}
|
|
|
|
/*
|
|
* Make sure that vm_areas for 2 buffers won't be merged together
|
|
*/
|
|
vma->vm_flags |= VM_DONTEXPAND;
|
|
|
|
/*
|
|
* Use common vm_area operations to track buffer refcount.
|
|
*/
|
|
vma->vm_private_data = &buf->handler;
|
|
vma->vm_ops = &vb2_common_vm_ops;
|
|
|
|
vma->vm_ops->open(vma);
|
|
|
|
return 0;
|
|
}
|
|
|
|
/*********************************************/
|
|
/* DMABUF ops for exporters */
|
|
/*********************************************/
|
|
|
|
struct vb2_vmalloc_attachment {
|
|
struct sg_table sgt;
|
|
enum dma_data_direction dma_dir;
|
|
};
|
|
|
|
static int vb2_vmalloc_dmabuf_ops_attach(struct dma_buf *dbuf, struct device *dev,
|
|
struct dma_buf_attachment *dbuf_attach)
|
|
{
|
|
struct vb2_vmalloc_attachment *attach;
|
|
struct vb2_vmalloc_buf *buf = dbuf->priv;
|
|
int num_pages = PAGE_ALIGN(buf->size) / PAGE_SIZE;
|
|
struct sg_table *sgt;
|
|
struct scatterlist *sg;
|
|
void *vaddr = buf->vaddr;
|
|
int ret;
|
|
int i;
|
|
|
|
attach = kzalloc(sizeof(*attach), GFP_KERNEL);
|
|
if (!attach)
|
|
return -ENOMEM;
|
|
|
|
sgt = &attach->sgt;
|
|
ret = sg_alloc_table(sgt, num_pages, GFP_KERNEL);
|
|
if (ret) {
|
|
kfree(attach);
|
|
return ret;
|
|
}
|
|
for_each_sg(sgt->sgl, sg, sgt->nents, i) {
|
|
struct page *page = vmalloc_to_page(vaddr);
|
|
|
|
if (!page) {
|
|
sg_free_table(sgt);
|
|
kfree(attach);
|
|
return -ENOMEM;
|
|
}
|
|
sg_set_page(sg, page, PAGE_SIZE, 0);
|
|
vaddr += PAGE_SIZE;
|
|
}
|
|
|
|
attach->dma_dir = DMA_NONE;
|
|
dbuf_attach->priv = attach;
|
|
return 0;
|
|
}
|
|
|
|
static void vb2_vmalloc_dmabuf_ops_detach(struct dma_buf *dbuf,
|
|
struct dma_buf_attachment *db_attach)
|
|
{
|
|
struct vb2_vmalloc_attachment *attach = db_attach->priv;
|
|
struct sg_table *sgt;
|
|
|
|
if (!attach)
|
|
return;
|
|
|
|
sgt = &attach->sgt;
|
|
|
|
/* release the scatterlist cache */
|
|
if (attach->dma_dir != DMA_NONE)
|
|
dma_unmap_sg(db_attach->dev, sgt->sgl, sgt->orig_nents,
|
|
attach->dma_dir);
|
|
sg_free_table(sgt);
|
|
kfree(attach);
|
|
db_attach->priv = NULL;
|
|
}
|
|
|
|
static struct sg_table *vb2_vmalloc_dmabuf_ops_map(
|
|
struct dma_buf_attachment *db_attach, enum dma_data_direction dma_dir)
|
|
{
|
|
struct vb2_vmalloc_attachment *attach = db_attach->priv;
|
|
/* stealing dmabuf mutex to serialize map/unmap operations */
|
|
struct mutex *lock = &db_attach->dmabuf->lock;
|
|
struct sg_table *sgt;
|
|
int ret;
|
|
|
|
mutex_lock(lock);
|
|
|
|
sgt = &attach->sgt;
|
|
/* return previously mapped sg table */
|
|
if (attach->dma_dir == dma_dir) {
|
|
mutex_unlock(lock);
|
|
return sgt;
|
|
}
|
|
|
|
/* release any previous cache */
|
|
if (attach->dma_dir != DMA_NONE) {
|
|
dma_unmap_sg(db_attach->dev, sgt->sgl, sgt->orig_nents,
|
|
attach->dma_dir);
|
|
attach->dma_dir = DMA_NONE;
|
|
}
|
|
|
|
/* mapping to the client with new direction */
|
|
ret = dma_map_sg(db_attach->dev, sgt->sgl, sgt->orig_nents, dma_dir);
|
|
if (ret <= 0) {
|
|
pr_err("failed to map scatterlist\n");
|
|
mutex_unlock(lock);
|
|
return ERR_PTR(-EIO);
|
|
}
|
|
|
|
attach->dma_dir = dma_dir;
|
|
|
|
mutex_unlock(lock);
|
|
|
|
return sgt;
|
|
}
|
|
|
|
static void vb2_vmalloc_dmabuf_ops_unmap(struct dma_buf_attachment *db_attach,
|
|
struct sg_table *sgt, enum dma_data_direction dma_dir)
|
|
{
|
|
/* nothing to be done here */
|
|
}
|
|
|
|
static void vb2_vmalloc_dmabuf_ops_release(struct dma_buf *dbuf)
|
|
{
|
|
/* drop reference obtained in vb2_vmalloc_get_dmabuf */
|
|
vb2_vmalloc_put(dbuf->priv);
|
|
}
|
|
|
|
static void *vb2_vmalloc_dmabuf_ops_kmap(struct dma_buf *dbuf, unsigned long pgnum)
|
|
{
|
|
struct vb2_vmalloc_buf *buf = dbuf->priv;
|
|
|
|
return buf->vaddr + pgnum * PAGE_SIZE;
|
|
}
|
|
|
|
static void *vb2_vmalloc_dmabuf_ops_vmap(struct dma_buf *dbuf)
|
|
{
|
|
struct vb2_vmalloc_buf *buf = dbuf->priv;
|
|
|
|
return buf->vaddr;
|
|
}
|
|
|
|
static int vb2_vmalloc_dmabuf_ops_mmap(struct dma_buf *dbuf,
|
|
struct vm_area_struct *vma)
|
|
{
|
|
return vb2_vmalloc_mmap(dbuf->priv, vma);
|
|
}
|
|
|
|
static struct dma_buf_ops vb2_vmalloc_dmabuf_ops = {
|
|
.attach = vb2_vmalloc_dmabuf_ops_attach,
|
|
.detach = vb2_vmalloc_dmabuf_ops_detach,
|
|
.map_dma_buf = vb2_vmalloc_dmabuf_ops_map,
|
|
.unmap_dma_buf = vb2_vmalloc_dmabuf_ops_unmap,
|
|
.kmap = vb2_vmalloc_dmabuf_ops_kmap,
|
|
.kmap_atomic = vb2_vmalloc_dmabuf_ops_kmap,
|
|
.vmap = vb2_vmalloc_dmabuf_ops_vmap,
|
|
.mmap = vb2_vmalloc_dmabuf_ops_mmap,
|
|
.release = vb2_vmalloc_dmabuf_ops_release,
|
|
};
|
|
|
|
static struct dma_buf *vb2_vmalloc_get_dmabuf(void *buf_priv, unsigned long flags)
|
|
{
|
|
struct vb2_vmalloc_buf *buf = buf_priv;
|
|
struct dma_buf *dbuf;
|
|
|
|
if (WARN_ON(!buf->vaddr))
|
|
return NULL;
|
|
|
|
dbuf = dma_buf_export(buf, &vb2_vmalloc_dmabuf_ops, buf->size, flags, NULL);
|
|
if (IS_ERR(dbuf))
|
|
return NULL;
|
|
|
|
/* dmabuf keeps reference to vb2 buffer */
|
|
atomic_inc(&buf->refcount);
|
|
|
|
return dbuf;
|
|
}
|
|
|
|
/*********************************************/
|
|
/* callbacks for DMABUF buffers */
|
|
/*********************************************/
|
|
|
|
static int vb2_vmalloc_map_dmabuf(void *mem_priv)
|
|
{
|
|
struct vb2_vmalloc_buf *buf = mem_priv;
|
|
|
|
buf->vaddr = dma_buf_vmap(buf->dbuf);
|
|
|
|
return buf->vaddr ? 0 : -EFAULT;
|
|
}
|
|
|
|
static void vb2_vmalloc_unmap_dmabuf(void *mem_priv)
|
|
{
|
|
struct vb2_vmalloc_buf *buf = mem_priv;
|
|
|
|
dma_buf_vunmap(buf->dbuf, buf->vaddr);
|
|
buf->vaddr = NULL;
|
|
}
|
|
|
|
static void vb2_vmalloc_detach_dmabuf(void *mem_priv)
|
|
{
|
|
struct vb2_vmalloc_buf *buf = mem_priv;
|
|
|
|
if (buf->vaddr)
|
|
dma_buf_vunmap(buf->dbuf, buf->vaddr);
|
|
|
|
kfree(buf);
|
|
}
|
|
|
|
static void *vb2_vmalloc_attach_dmabuf(void *alloc_ctx, struct dma_buf *dbuf,
|
|
unsigned long size, enum dma_data_direction dma_dir)
|
|
{
|
|
struct vb2_vmalloc_buf *buf;
|
|
|
|
if (dbuf->size < size)
|
|
return ERR_PTR(-EFAULT);
|
|
|
|
buf = kzalloc(sizeof(*buf), GFP_KERNEL);
|
|
if (!buf)
|
|
return ERR_PTR(-ENOMEM);
|
|
|
|
buf->dbuf = dbuf;
|
|
buf->dma_dir = dma_dir;
|
|
buf->size = size;
|
|
|
|
return buf;
|
|
}
|
|
|
|
|
|
const struct vb2_mem_ops vb2_vmalloc_memops = {
|
|
.alloc = vb2_vmalloc_alloc,
|
|
.put = vb2_vmalloc_put,
|
|
.get_userptr = vb2_vmalloc_get_userptr,
|
|
.put_userptr = vb2_vmalloc_put_userptr,
|
|
.get_dmabuf = vb2_vmalloc_get_dmabuf,
|
|
.map_dmabuf = vb2_vmalloc_map_dmabuf,
|
|
.unmap_dmabuf = vb2_vmalloc_unmap_dmabuf,
|
|
.attach_dmabuf = vb2_vmalloc_attach_dmabuf,
|
|
.detach_dmabuf = vb2_vmalloc_detach_dmabuf,
|
|
.vaddr = vb2_vmalloc_vaddr,
|
|
.mmap = vb2_vmalloc_mmap,
|
|
.num_users = vb2_vmalloc_num_users,
|
|
};
|
|
EXPORT_SYMBOL_GPL(vb2_vmalloc_memops);
|
|
|
|
MODULE_DESCRIPTION("vmalloc memory handling routines for videobuf2");
|
|
MODULE_AUTHOR("Pawel Osciak <pawel@osciak.com>");
|
|
MODULE_LICENSE("GPL");
|