^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 1) // SPDX-License-Identifier: GPL-2.0
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 2) #include <linux/cred.h>
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 3) #include <linux/device.h>
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 4) #include <linux/dma-buf.h>
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 5) #include <linux/highmem.h>
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 6) #include <linux/init.h>
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 7) #include <linux/kernel.h>
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 8) #include <linux/memfd.h>
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 9) #include <linux/miscdevice.h>
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 10) #include <linux/module.h>
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 11) #include <linux/shmem_fs.h>
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 12) #include <linux/slab.h>
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 13) #include <linux/udmabuf.h>
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 14)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 15) static const u32 list_limit = 1024; /* udmabuf_create_list->count limit */
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 16) static const size_t size_limit_mb = 64; /* total dmabuf size, in megabytes */
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 17)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 18) struct udmabuf {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 19) pgoff_t pagecount;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 20) struct page **pages;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 21) struct sg_table *sg;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 22) struct miscdevice *device;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 23) };
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 24)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 25) static vm_fault_t udmabuf_vm_fault(struct vm_fault *vmf)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 26) {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 27) struct vm_area_struct *vma = vmf->vma;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 28) struct udmabuf *ubuf = vma->vm_private_data;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 29)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 30) vmf->page = ubuf->pages[vmf->pgoff];
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 31) get_page(vmf->page);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 32) return 0;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 33) }
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 34)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 35) static const struct vm_operations_struct udmabuf_vm_ops = {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 36) .fault = udmabuf_vm_fault,
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 37) };
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 38)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 39) static int mmap_udmabuf(struct dma_buf *buf, struct vm_area_struct *vma)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 40) {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 41) struct udmabuf *ubuf = buf->priv;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 42)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 43) if ((vma->vm_flags & (VM_SHARED | VM_MAYSHARE)) == 0)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 44) return -EINVAL;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 45)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 46) vma->vm_ops = &udmabuf_vm_ops;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 47) vma->vm_private_data = ubuf;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 48) return 0;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 49) }
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 50)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 51) static struct sg_table *get_sg_table(struct device *dev, struct dma_buf *buf,
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 52) enum dma_data_direction direction)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 53) {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 54) struct udmabuf *ubuf = buf->priv;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 55) struct sg_table *sg;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 56) int ret;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 57)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 58) sg = kzalloc(sizeof(*sg), GFP_KERNEL);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 59) if (!sg)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 60) return ERR_PTR(-ENOMEM);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 61) ret = sg_alloc_table_from_pages(sg, ubuf->pages, ubuf->pagecount,
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 62) 0, ubuf->pagecount << PAGE_SHIFT,
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 63) GFP_KERNEL);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 64) if (ret < 0)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 65) goto err;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 66) ret = dma_map_sgtable(dev, sg, direction, 0);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 67) if (ret < 0)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 68) goto err;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 69) return sg;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 70)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 71) err:
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 72) sg_free_table(sg);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 73) kfree(sg);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 74) return ERR_PTR(ret);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 75) }
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 76)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 77) static void put_sg_table(struct device *dev, struct sg_table *sg,
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 78) enum dma_data_direction direction)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 79) {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 80) dma_unmap_sgtable(dev, sg, direction, 0);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 81) sg_free_table(sg);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 82) kfree(sg);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 83) }
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 84)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 85) static struct sg_table *map_udmabuf(struct dma_buf_attachment *at,
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 86) enum dma_data_direction direction)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 87) {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 88) return get_sg_table(at->dev, at->dmabuf, direction);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 89) }
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 90)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 91) static void unmap_udmabuf(struct dma_buf_attachment *at,
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 92) struct sg_table *sg,
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 93) enum dma_data_direction direction)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 94) {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 95) return put_sg_table(at->dev, sg, direction);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 96) }
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 97)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 98) static void release_udmabuf(struct dma_buf *buf)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 99) {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 100) struct udmabuf *ubuf = buf->priv;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 101) struct device *dev = ubuf->device->this_device;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 102) pgoff_t pg;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 103)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 104) if (ubuf->sg)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 105) put_sg_table(dev, ubuf->sg, DMA_BIDIRECTIONAL);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 106)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 107) for (pg = 0; pg < ubuf->pagecount; pg++)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 108) put_page(ubuf->pages[pg]);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 109) kfree(ubuf->pages);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 110) kfree(ubuf);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 111) }
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 112)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 113) static int begin_cpu_udmabuf(struct dma_buf *buf,
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 114) enum dma_data_direction direction)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 115) {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 116) struct udmabuf *ubuf = buf->priv;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 117) struct device *dev = ubuf->device->this_device;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 118)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 119) if (!ubuf->sg) {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 120) ubuf->sg = get_sg_table(dev, buf, direction);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 121) if (IS_ERR(ubuf->sg))
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 122) return PTR_ERR(ubuf->sg);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 123) } else {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 124) dma_sync_sg_for_cpu(dev, ubuf->sg->sgl, ubuf->sg->nents,
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 125) direction);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 126) }
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 127)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 128) return 0;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 129) }
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 130)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 131) static int end_cpu_udmabuf(struct dma_buf *buf,
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 132) enum dma_data_direction direction)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 133) {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 134) struct udmabuf *ubuf = buf->priv;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 135) struct device *dev = ubuf->device->this_device;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 136)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 137) if (!ubuf->sg)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 138) return -EINVAL;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 139)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 140) dma_sync_sg_for_device(dev, ubuf->sg->sgl, ubuf->sg->nents, direction);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 141) return 0;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 142) }
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 143)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 144) static const struct dma_buf_ops udmabuf_ops = {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 145) .cache_sgt_mapping = true,
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 146) .map_dma_buf = map_udmabuf,
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 147) .unmap_dma_buf = unmap_udmabuf,
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 148) .release = release_udmabuf,
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 149) .mmap = mmap_udmabuf,
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 150) .begin_cpu_access = begin_cpu_udmabuf,
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 151) .end_cpu_access = end_cpu_udmabuf,
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 152) };
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 153)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 154) #define SEALS_WANTED (F_SEAL_SHRINK)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 155) #define SEALS_DENIED (F_SEAL_WRITE)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 156)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 157) static long udmabuf_create(struct miscdevice *device,
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 158) struct udmabuf_create_list *head,
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 159) struct udmabuf_create_item *list)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 160) {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 161) DEFINE_DMA_BUF_EXPORT_INFO(exp_info);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 162) struct file *memfd = NULL;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 163) struct udmabuf *ubuf;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 164) struct dma_buf *buf;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 165) pgoff_t pgoff, pgcnt, pgidx, pgbuf = 0, pglimit;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 166) struct page *page;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 167) int seals, ret = -EINVAL;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 168) u32 i, flags;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 169)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 170) ubuf = kzalloc(sizeof(*ubuf), GFP_KERNEL);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 171) if (!ubuf)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 172) return -ENOMEM;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 173)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 174) pglimit = (size_limit_mb * 1024 * 1024) >> PAGE_SHIFT;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 175) for (i = 0; i < head->count; i++) {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 176) if (!IS_ALIGNED(list[i].offset, PAGE_SIZE))
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 177) goto err;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 178) if (!IS_ALIGNED(list[i].size, PAGE_SIZE))
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 179) goto err;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 180) ubuf->pagecount += list[i].size >> PAGE_SHIFT;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 181) if (ubuf->pagecount > pglimit)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 182) goto err;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 183) }
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 184)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 185) if (!ubuf->pagecount)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 186) goto err;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 187)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 188) ubuf->pages = kmalloc_array(ubuf->pagecount, sizeof(*ubuf->pages),
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 189) GFP_KERNEL);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 190) if (!ubuf->pages) {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 191) ret = -ENOMEM;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 192) goto err;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 193) }
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 194)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 195) pgbuf = 0;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 196) for (i = 0; i < head->count; i++) {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 197) ret = -EBADFD;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 198) memfd = fget(list[i].memfd);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 199) if (!memfd)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 200) goto err;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 201) if (!shmem_mapping(file_inode(memfd)->i_mapping))
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 202) goto err;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 203) seals = memfd_fcntl(memfd, F_GET_SEALS, 0);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 204) if (seals == -EINVAL)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 205) goto err;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 206) ret = -EINVAL;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 207) if ((seals & SEALS_WANTED) != SEALS_WANTED ||
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 208) (seals & SEALS_DENIED) != 0)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 209) goto err;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 210) pgoff = list[i].offset >> PAGE_SHIFT;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 211) pgcnt = list[i].size >> PAGE_SHIFT;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 212) for (pgidx = 0; pgidx < pgcnt; pgidx++) {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 213) page = shmem_read_mapping_page(
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 214) file_inode(memfd)->i_mapping, pgoff + pgidx);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 215) if (IS_ERR(page)) {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 216) ret = PTR_ERR(page);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 217) goto err;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 218) }
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 219) ubuf->pages[pgbuf++] = page;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 220) }
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 221) fput(memfd);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 222) memfd = NULL;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 223) }
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 224)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 225) exp_info.ops = &udmabuf_ops;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 226) exp_info.size = ubuf->pagecount << PAGE_SHIFT;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 227) exp_info.priv = ubuf;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 228) exp_info.flags = O_RDWR;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 229)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 230) ubuf->device = device;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 231) buf = dma_buf_export(&exp_info);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 232) if (IS_ERR(buf)) {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 233) ret = PTR_ERR(buf);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 234) goto err;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 235) }
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 236)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 237) flags = 0;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 238) if (head->flags & UDMABUF_FLAGS_CLOEXEC)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 239) flags |= O_CLOEXEC;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 240) return dma_buf_fd(buf, flags);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 241)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 242) err:
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 243) while (pgbuf > 0)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 244) put_page(ubuf->pages[--pgbuf]);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 245) if (memfd)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 246) fput(memfd);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 247) kfree(ubuf->pages);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 248) kfree(ubuf);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 249) return ret;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 250) }
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 251)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 252) static long udmabuf_ioctl_create(struct file *filp, unsigned long arg)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 253) {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 254) struct udmabuf_create create;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 255) struct udmabuf_create_list head;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 256) struct udmabuf_create_item list;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 257)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 258) if (copy_from_user(&create, (void __user *)arg,
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 259) sizeof(create)))
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 260) return -EFAULT;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 261)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 262) head.flags = create.flags;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 263) head.count = 1;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 264) list.memfd = create.memfd;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 265) list.offset = create.offset;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 266) list.size = create.size;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 267)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 268) return udmabuf_create(filp->private_data, &head, &list);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 269) }
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 270)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 271) static long udmabuf_ioctl_create_list(struct file *filp, unsigned long arg)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 272) {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 273) struct udmabuf_create_list head;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 274) struct udmabuf_create_item *list;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 275) int ret = -EINVAL;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 276) u32 lsize;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 277)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 278) if (copy_from_user(&head, (void __user *)arg, sizeof(head)))
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 279) return -EFAULT;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 280) if (head.count > list_limit)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 281) return -EINVAL;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 282) lsize = sizeof(struct udmabuf_create_item) * head.count;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 283) list = memdup_user((void __user *)(arg + sizeof(head)), lsize);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 284) if (IS_ERR(list))
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 285) return PTR_ERR(list);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 286)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 287) ret = udmabuf_create(filp->private_data, &head, list);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 288) kfree(list);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 289) return ret;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 290) }
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 291)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 292) static long udmabuf_ioctl(struct file *filp, unsigned int ioctl,
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 293) unsigned long arg)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 294) {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 295) long ret;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 296)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 297) switch (ioctl) {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 298) case UDMABUF_CREATE:
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 299) ret = udmabuf_ioctl_create(filp, arg);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 300) break;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 301) case UDMABUF_CREATE_LIST:
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 302) ret = udmabuf_ioctl_create_list(filp, arg);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 303) break;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 304) default:
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 305) ret = -ENOTTY;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 306) break;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 307) }
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 308) return ret;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 309) }
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 310)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 311) static const struct file_operations udmabuf_fops = {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 312) .owner = THIS_MODULE,
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 313) .unlocked_ioctl = udmabuf_ioctl,
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 314) #ifdef CONFIG_COMPAT
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 315) .compat_ioctl = udmabuf_ioctl,
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 316) #endif
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 317) };
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 318)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 319) static struct miscdevice udmabuf_misc = {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 320) .minor = MISC_DYNAMIC_MINOR,
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 321) .name = "udmabuf",
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 322) .fops = &udmabuf_fops,
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 323) };
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 324)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 325) static int __init udmabuf_dev_init(void)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 326) {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 327) return misc_register(&udmabuf_misc);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 328) }
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 329)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 330) static void __exit udmabuf_dev_exit(void)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 331) {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 332) misc_deregister(&udmabuf_misc);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 333) }
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 334)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 335) module_init(udmabuf_dev_init)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 336) module_exit(udmabuf_dev_exit)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 337)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 338) MODULE_AUTHOR("Gerd Hoffmann <kraxel@redhat.com>");
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 339) MODULE_LICENSE("GPL v2");
Orange Pi5 kernel
Deprecated Linux kernel 5.10.110 for OrangePi 5/5B/5+ boards
3 Commits
0 Branches
0 Tags