Am 18.07.2017 um 05:57 schrieb Felix Kuehling: > Allows gdb to access contents of user mode mapped BOs. System memory > is handled by TTM using kmap. Other memory pools require a new driver > callback in ttm_bo_driver. > > v2: > * kmap only one page at a time > * swap in BO if needed > * make driver callback more generic to handle private memory pools > * document callback return value > * WARN_ON -> WARN_ON_ONCE > > Signed-off-by: Felix Kuehling <Felix.Kuehling at amd.com> Reviewed-by: Christian König <christian.koenig at amd.com> for both. > --- > drivers/gpu/drm/ttm/ttm_bo_vm.c | 79 ++++++++++++++++++++++++++++++++++++++++- > include/drm/ttm/ttm_bo_driver.h | 17 +++++++++ > 2 files changed, 95 insertions(+), 1 deletion(-) > > diff --git a/drivers/gpu/drm/ttm/ttm_bo_vm.c b/drivers/gpu/drm/ttm/ttm_bo_vm.c > index 9f53df9..945985e 100644 > --- a/drivers/gpu/drm/ttm/ttm_bo_vm.c > +++ b/drivers/gpu/drm/ttm/ttm_bo_vm.c > @@ -294,10 +294,87 @@ static void ttm_bo_vm_close(struct vm_area_struct *vma) > vma->vm_private_data = NULL; > } > > +static int ttm_bo_vm_access_kmap(struct ttm_buffer_object *bo, > + unsigned long offset, > + void *buf, int len, int write) > +{ > + unsigned long page = offset >> PAGE_SHIFT; > + unsigned long bytes_left = len; > + int ret; > + > + /* Copy a page at a time, that way no extra virtual address > + * mapping is needed > + */ > + offset -= page << PAGE_SHIFT; > + do { > + unsigned long bytes = min(bytes_left, PAGE_SIZE - offset); > + struct ttm_bo_kmap_obj map; > + void *ptr; > + bool is_iomem; > + > + ret = ttm_bo_kmap(bo, page, 1, &map); > + if (ret) > + return ret; > + > + ptr = (uint8_t *)ttm_kmap_obj_virtual(&map, &is_iomem) + offset; > + WARN_ON_ONCE(is_iomem); > + if (write) > + memcpy(ptr, buf, bytes); > + else > + memcpy(buf, ptr, bytes); > + ttm_bo_kunmap(&map); > + > + page++; > + bytes_left -= bytes; > + offset = 0; > + } while (bytes_left); > + > + return len; > +} > + > +static int ttm_bo_vm_access(struct vm_area_struct *vma, unsigned long addr, > + void *buf, int len, int write) > +{ > + unsigned long offset = (addr) - vma->vm_start; > + struct ttm_buffer_object *bo = vma->vm_private_data; > + int ret; > + > + if (len < 1 || (offset + len) >> PAGE_SHIFT > bo->num_pages) > + return -EIO; > + > + ret = ttm_bo_reserve(bo, true, false, NULL); > + if (ret) > + return ret; > + > + switch(bo->mem.mem_type) { > + case TTM_PL_SYSTEM: > + if (unlikely(bo->ttm->page_flags & TTM_PAGE_FLAG_SWAPPED)) { > + ret = ttm_tt_swapin(bo->ttm); > + if (unlikely(ret != 0)) > + return ret; > + } > + /* fall through */ > + case TTM_PL_TT: > + ret = ttm_bo_vm_access_kmap(bo, offset, buf, len, write); > + break; > + default: > + if (bo->bdev->driver->access_memory) > + ret = bo->bdev->driver->access_memory( > + bo, offset, buf, len, write); > + else > + ret = -EIO; > + } > + > + ttm_bo_unreserve(bo); > + > + return ret; > +} > + > static const struct vm_operations_struct ttm_bo_vm_ops = { > .fault = ttm_bo_vm_fault, > .open = ttm_bo_vm_open, > - .close = ttm_bo_vm_close > + .close = ttm_bo_vm_close, > + .access = ttm_bo_vm_access > }; > > static struct ttm_buffer_object *ttm_bo_vm_lookup(struct ttm_bo_device *bdev, > diff --git a/include/drm/ttm/ttm_bo_driver.h b/include/drm/ttm/ttm_bo_driver.h > index 6bbd34d..04380ba 100644 > --- a/include/drm/ttm/ttm_bo_driver.h > +++ b/include/drm/ttm/ttm_bo_driver.h > @@ -471,6 +471,23 @@ struct ttm_bo_driver { > */ > unsigned long (*io_mem_pfn)(struct ttm_buffer_object *bo, > unsigned long page_offset); > + > + /** > + * Read/write memory buffers for ptrace access > + * > + * @bo: the BO to access > + * @offset: the offset from the start of the BO > + * @buf: pointer to source/destination buffer > + * @len: number of bytes to copy > + * @write: whether to read (0) from or write (non-0) to BO > + * > + * If successful, this function should return the number of > + * bytes copied, -EIO otherwise. If the number of bytes > + * returned is < len, the function may be called again with > + * the remainder of the buffer to copy. > + */ > + int (*access_memory)(struct ttm_buffer_object *bo, unsigned long offset, > + void *buf, int len, int write); > }; > > /**