linux/drivers/dma-buf/udmabuf.c
Daniel Vetter 6c7f27441d drm-misc-next for v6.6:
UAPI Changes:
 
  * fbdev:
    * Make fbdev userspace interfaces optional; only leaves the
      framebuffer console active
 
  * prime:
    * Support dma-buf self-import for all drivers automatically: improves
      support for many userspace compositors
 
 Cross-subsystem Changes:
 
  * backlight:
    * Fix interaction with fbdev in several drivers
 
  * base: Convert struct platform.remove to return void; part of a larger,
    tree-wide effort
 
  * dma-buf: Acquire reservation lock for mmap() in exporters; part
    of an on-going effort to simplify locking around dma-bufs
 
  * fbdev:
    * Use Linux device instead of fbdev device in many places
    * Use deferred-I/O helper macros in various drivers
 
  * i2c: Convert struct i2c from .probe_new to .probe; part of a larger,
    tree-wide effort
 
  * video:
    * Avoid including <linux/screen_info.h>
 
 Core Changes:
 
  * atomic:
    * Improve logging
 
  * prime:
    * Remove struct drm_driver.gem_prime_mmap plus driver updates: all
      drivers now implement this callback with drm_gem_prime_mmap()
 
  * gem:
    * Support execution contexts: provides locking over multiple GEM
      objects
 
  * ttm:
    * Support init_on_free
    * Swapout fixes
 
 Driver Changes:
 
  * accel:
    * ivpu: MMU updates; Support debugfs
 
  * ast:
    * Improve device-model detection
    * Cleanups
 
  * bridge:
    * dw-hdmi: Improve support for YUV420 bus format
    * dw-mipi-dsi: Fix enable/disable of DSI controller
    * lt9611uxc: Use MODULE_FIRMWARE()
    * ps8640: Remove broken EDID code
    * samsung-dsim: Fix command transfer
    * tc358764: Handle HS/VS polarity; Use BIT() macro; Various cleanups
    * Cleanups
 
  * ingenic:
    * Kconfig REGMAP fixes
 
  * loongson:
    * Support display controller
 
  * mgag200:
    * Minor fixes
 
  * mxsfb:
    * Support disabling overlay planes
 
  * nouveau:
    * Improve VRAM detection
    * Various fixes and cleanups
 
  * panel:
    * panel-edp: Support AUO B116XAB01.4
    * Support Visionox R66451 plus DT bindings
    * Cleanups
 
  * ssd130x:
    * Support per-controller default resolution plus DT bindings
    * Reduce memory-allocation overhead
    * Cleanups
 
  * tidss:
    * Support TI AM625 plus DT bindings
    * Implement new connector model plus driver updates
 
  * vkms
    * Improve write-back support
    * Documentation fixes
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Merge tag 'drm-misc-next-2023-07-13' of git://anongit.freedesktop.org/drm/drm-misc into drm-next

drm-misc-next for v6.6:

UAPI Changes:

 * fbdev:
   * Make fbdev userspace interfaces optional; only leaves the
     framebuffer console active

 * prime:
   * Support dma-buf self-import for all drivers automatically: improves
     support for many userspace compositors

Cross-subsystem Changes:

 * backlight:
   * Fix interaction with fbdev in several drivers

 * base: Convert struct platform.remove to return void; part of a larger,
   tree-wide effort

 * dma-buf: Acquire reservation lock for mmap() in exporters; part
   of an on-going effort to simplify locking around dma-bufs

 * fbdev:
   * Use Linux device instead of fbdev device in many places
   * Use deferred-I/O helper macros in various drivers

 * i2c: Convert struct i2c from .probe_new to .probe; part of a larger,
   tree-wide effort

 * video:
   * Avoid including <linux/screen_info.h>

Core Changes:

 * atomic:
   * Improve logging

 * prime:
   * Remove struct drm_driver.gem_prime_mmap plus driver updates: all
     drivers now implement this callback with drm_gem_prime_mmap()

 * gem:
   * Support execution contexts: provides locking over multiple GEM
     objects

 * ttm:
   * Support init_on_free
   * Swapout fixes

Driver Changes:

 * accel:
   * ivpu: MMU updates; Support debugfs

 * ast:
   * Improve device-model detection
   * Cleanups

 * bridge:
   * dw-hdmi: Improve support for YUV420 bus format
   * dw-mipi-dsi: Fix enable/disable of DSI controller
   * lt9611uxc: Use MODULE_FIRMWARE()
   * ps8640: Remove broken EDID code
   * samsung-dsim: Fix command transfer
   * tc358764: Handle HS/VS polarity; Use BIT() macro; Various cleanups
   * Cleanups

 * ingenic:
   * Kconfig REGMAP fixes

 * loongson:
   * Support display controller

 * mgag200:
   * Minor fixes

 * mxsfb:
   * Support disabling overlay planes

 * nouveau:
   * Improve VRAM detection
   * Various fixes and cleanups

 * panel:
   * panel-edp: Support AUO B116XAB01.4
   * Support Visionox R66451 plus DT bindings
   * Cleanups

 * ssd130x:
   * Support per-controller default resolution plus DT bindings
   * Reduce memory-allocation overhead
   * Cleanups

 * tidss:
   * Support TI AM625 plus DT bindings
   * Implement new connector model plus driver updates

 * vkms
   * Improve write-back support
   * Documentation fixes

Signed-off-by: Daniel Vetter <daniel.vetter@ffwll.ch>
From: Thomas Zimmermann <tzimmermann@suse.de>
Link: https://patchwork.freedesktop.org/patch/msgid/20230713090830.GA23281@linux-uq9g
2023-07-17 15:37:57 +02:00

396 lines
8.8 KiB
C

// SPDX-License-Identifier: GPL-2.0
#include <linux/cred.h>
#include <linux/device.h>
#include <linux/dma-buf.h>
#include <linux/dma-resv.h>
#include <linux/highmem.h>
#include <linux/init.h>
#include <linux/kernel.h>
#include <linux/memfd.h>
#include <linux/miscdevice.h>
#include <linux/module.h>
#include <linux/shmem_fs.h>
#include <linux/slab.h>
#include <linux/udmabuf.h>
#include <linux/vmalloc.h>
#include <linux/iosys-map.h>
static int list_limit = 1024;
module_param(list_limit, int, 0644);
MODULE_PARM_DESC(list_limit, "udmabuf_create_list->count limit. Default is 1024.");
static int size_limit_mb = 64;
module_param(size_limit_mb, int, 0644);
MODULE_PARM_DESC(size_limit_mb, "Max size of a dmabuf, in megabytes. Default is 64.");
struct udmabuf {
pgoff_t pagecount;
struct page **pages;
struct sg_table *sg;
struct miscdevice *device;
};
static vm_fault_t udmabuf_vm_fault(struct vm_fault *vmf)
{
struct vm_area_struct *vma = vmf->vma;
struct udmabuf *ubuf = vma->vm_private_data;
pgoff_t pgoff = vmf->pgoff;
if (pgoff >= ubuf->pagecount)
return VM_FAULT_SIGBUS;
vmf->page = ubuf->pages[pgoff];
get_page(vmf->page);
return 0;
}
static const struct vm_operations_struct udmabuf_vm_ops = {
.fault = udmabuf_vm_fault,
};
static int mmap_udmabuf(struct dma_buf *buf, struct vm_area_struct *vma)
{
struct udmabuf *ubuf = buf->priv;
if ((vma->vm_flags & (VM_SHARED | VM_MAYSHARE)) == 0)
return -EINVAL;
vma->vm_ops = &udmabuf_vm_ops;
vma->vm_private_data = ubuf;
return 0;
}
static int vmap_udmabuf(struct dma_buf *buf, struct iosys_map *map)
{
struct udmabuf *ubuf = buf->priv;
void *vaddr;
dma_resv_assert_held(buf->resv);
vaddr = vm_map_ram(ubuf->pages, ubuf->pagecount, -1);
if (!vaddr)
return -EINVAL;
iosys_map_set_vaddr(map, vaddr);
return 0;
}
static void vunmap_udmabuf(struct dma_buf *buf, struct iosys_map *map)
{
struct udmabuf *ubuf = buf->priv;
dma_resv_assert_held(buf->resv);
vm_unmap_ram(map->vaddr, ubuf->pagecount);
}
static struct sg_table *get_sg_table(struct device *dev, struct dma_buf *buf,
enum dma_data_direction direction)
{
struct udmabuf *ubuf = buf->priv;
struct sg_table *sg;
int ret;
sg = kzalloc(sizeof(*sg), GFP_KERNEL);
if (!sg)
return ERR_PTR(-ENOMEM);
ret = sg_alloc_table_from_pages(sg, ubuf->pages, ubuf->pagecount,
0, ubuf->pagecount << PAGE_SHIFT,
GFP_KERNEL);
if (ret < 0)
goto err;
ret = dma_map_sgtable(dev, sg, direction, 0);
if (ret < 0)
goto err;
return sg;
err:
sg_free_table(sg);
kfree(sg);
return ERR_PTR(ret);
}
static void put_sg_table(struct device *dev, struct sg_table *sg,
enum dma_data_direction direction)
{
dma_unmap_sgtable(dev, sg, direction, 0);
sg_free_table(sg);
kfree(sg);
}
static struct sg_table *map_udmabuf(struct dma_buf_attachment *at,
enum dma_data_direction direction)
{
return get_sg_table(at->dev, at->dmabuf, direction);
}
static void unmap_udmabuf(struct dma_buf_attachment *at,
struct sg_table *sg,
enum dma_data_direction direction)
{
return put_sg_table(at->dev, sg, direction);
}
static void release_udmabuf(struct dma_buf *buf)
{
struct udmabuf *ubuf = buf->priv;
struct device *dev = ubuf->device->this_device;
pgoff_t pg;
if (ubuf->sg)
put_sg_table(dev, ubuf->sg, DMA_BIDIRECTIONAL);
for (pg = 0; pg < ubuf->pagecount; pg++)
put_page(ubuf->pages[pg]);
kfree(ubuf->pages);
kfree(ubuf);
}
static int begin_cpu_udmabuf(struct dma_buf *buf,
enum dma_data_direction direction)
{
struct udmabuf *ubuf = buf->priv;
struct device *dev = ubuf->device->this_device;
int ret = 0;
if (!ubuf->sg) {
ubuf->sg = get_sg_table(dev, buf, direction);
if (IS_ERR(ubuf->sg)) {
ret = PTR_ERR(ubuf->sg);
ubuf->sg = NULL;
}
} else {
dma_sync_sg_for_cpu(dev, ubuf->sg->sgl, ubuf->sg->nents,
direction);
}
return ret;
}
static int end_cpu_udmabuf(struct dma_buf *buf,
enum dma_data_direction direction)
{
struct udmabuf *ubuf = buf->priv;
struct device *dev = ubuf->device->this_device;
if (!ubuf->sg)
return -EINVAL;
dma_sync_sg_for_device(dev, ubuf->sg->sgl, ubuf->sg->nents, direction);
return 0;
}
static const struct dma_buf_ops udmabuf_ops = {
.cache_sgt_mapping = true,
.map_dma_buf = map_udmabuf,
.unmap_dma_buf = unmap_udmabuf,
.release = release_udmabuf,
.mmap = mmap_udmabuf,
.vmap = vmap_udmabuf,
.vunmap = vunmap_udmabuf,
.begin_cpu_access = begin_cpu_udmabuf,
.end_cpu_access = end_cpu_udmabuf,
};
#define SEALS_WANTED (F_SEAL_SHRINK)
#define SEALS_DENIED (F_SEAL_WRITE)
static long udmabuf_create(struct miscdevice *device,
struct udmabuf_create_list *head,
struct udmabuf_create_item *list)
{
DEFINE_DMA_BUF_EXPORT_INFO(exp_info);
struct file *memfd = NULL;
struct address_space *mapping = NULL;
struct udmabuf *ubuf;
struct dma_buf *buf;
pgoff_t pgoff, pgcnt, pgidx, pgbuf = 0, pglimit;
struct page *page;
int seals, ret = -EINVAL;
u32 i, flags;
ubuf = kzalloc(sizeof(*ubuf), GFP_KERNEL);
if (!ubuf)
return -ENOMEM;
pglimit = (size_limit_mb * 1024 * 1024) >> PAGE_SHIFT;
for (i = 0; i < head->count; i++) {
if (!IS_ALIGNED(list[i].offset, PAGE_SIZE))
goto err;
if (!IS_ALIGNED(list[i].size, PAGE_SIZE))
goto err;
ubuf->pagecount += list[i].size >> PAGE_SHIFT;
if (ubuf->pagecount > pglimit)
goto err;
}
if (!ubuf->pagecount)
goto err;
ubuf->pages = kmalloc_array(ubuf->pagecount, sizeof(*ubuf->pages),
GFP_KERNEL);
if (!ubuf->pages) {
ret = -ENOMEM;
goto err;
}
pgbuf = 0;
for (i = 0; i < head->count; i++) {
ret = -EBADFD;
memfd = fget(list[i].memfd);
if (!memfd)
goto err;
mapping = memfd->f_mapping;
if (!shmem_mapping(mapping))
goto err;
seals = memfd_fcntl(memfd, F_GET_SEALS, 0);
if (seals == -EINVAL)
goto err;
ret = -EINVAL;
if ((seals & SEALS_WANTED) != SEALS_WANTED ||
(seals & SEALS_DENIED) != 0)
goto err;
pgoff = list[i].offset >> PAGE_SHIFT;
pgcnt = list[i].size >> PAGE_SHIFT;
for (pgidx = 0; pgidx < pgcnt; pgidx++) {
page = shmem_read_mapping_page(mapping, pgoff + pgidx);
if (IS_ERR(page)) {
ret = PTR_ERR(page);
goto err;
}
ubuf->pages[pgbuf++] = page;
}
fput(memfd);
memfd = NULL;
}
exp_info.ops = &udmabuf_ops;
exp_info.size = ubuf->pagecount << PAGE_SHIFT;
exp_info.priv = ubuf;
exp_info.flags = O_RDWR;
ubuf->device = device;
buf = dma_buf_export(&exp_info);
if (IS_ERR(buf)) {
ret = PTR_ERR(buf);
goto err;
}
flags = 0;
if (head->flags & UDMABUF_FLAGS_CLOEXEC)
flags |= O_CLOEXEC;
return dma_buf_fd(buf, flags);
err:
while (pgbuf > 0)
put_page(ubuf->pages[--pgbuf]);
if (memfd)
fput(memfd);
kfree(ubuf->pages);
kfree(ubuf);
return ret;
}
static long udmabuf_ioctl_create(struct file *filp, unsigned long arg)
{
struct udmabuf_create create;
struct udmabuf_create_list head;
struct udmabuf_create_item list;
if (copy_from_user(&create, (void __user *)arg,
sizeof(create)))
return -EFAULT;
head.flags = create.flags;
head.count = 1;
list.memfd = create.memfd;
list.offset = create.offset;
list.size = create.size;
return udmabuf_create(filp->private_data, &head, &list);
}
static long udmabuf_ioctl_create_list(struct file *filp, unsigned long arg)
{
struct udmabuf_create_list head;
struct udmabuf_create_item *list;
int ret = -EINVAL;
u32 lsize;
if (copy_from_user(&head, (void __user *)arg, sizeof(head)))
return -EFAULT;
if (head.count > list_limit)
return -EINVAL;
lsize = sizeof(struct udmabuf_create_item) * head.count;
list = memdup_user((void __user *)(arg + sizeof(head)), lsize);
if (IS_ERR(list))
return PTR_ERR(list);
ret = udmabuf_create(filp->private_data, &head, list);
kfree(list);
return ret;
}
static long udmabuf_ioctl(struct file *filp, unsigned int ioctl,
unsigned long arg)
{
long ret;
switch (ioctl) {
case UDMABUF_CREATE:
ret = udmabuf_ioctl_create(filp, arg);
break;
case UDMABUF_CREATE_LIST:
ret = udmabuf_ioctl_create_list(filp, arg);
break;
default:
ret = -ENOTTY;
break;
}
return ret;
}
static const struct file_operations udmabuf_fops = {
.owner = THIS_MODULE,
.unlocked_ioctl = udmabuf_ioctl,
#ifdef CONFIG_COMPAT
.compat_ioctl = udmabuf_ioctl,
#endif
};
static struct miscdevice udmabuf_misc = {
.minor = MISC_DYNAMIC_MINOR,
.name = "udmabuf",
.fops = &udmabuf_fops,
};
static int __init udmabuf_dev_init(void)
{
int ret;
ret = misc_register(&udmabuf_misc);
if (ret < 0) {
pr_err("Could not initialize udmabuf device\n");
return ret;
}
ret = dma_coerce_mask_and_coherent(udmabuf_misc.this_device,
DMA_BIT_MASK(64));
if (ret < 0) {
pr_err("Could not setup DMA mask for udmabuf device\n");
misc_deregister(&udmabuf_misc);
return ret;
}
return 0;
}
static void __exit udmabuf_dev_exit(void)
{
misc_deregister(&udmabuf_misc);
}
module_init(udmabuf_dev_init)
module_exit(udmabuf_dev_exit)
MODULE_AUTHOR("Gerd Hoffmann <kraxel@redhat.com>");