media: atomisp: Add hmm_create_from_vmalloc_buf() function

Add a new hmm creating function to create a vmm object from a vmalloc-ed
kernel buffer. This is a preparation patch for adding videobuf2 (and
working MMAP mode) support.
Reviewed-by: Andy Shevchenko <andy@kernel.org>
Signed-off-by: Hans de Goede <hdegoede@redhat.com>
Signed-off-by: Mauro Carvalho Chehab <mchehab@kernel.org>

drivers/staging/media/atomisp/include/hmm/hmm.h

@@ -38,6 +38,8 @@ void hmm_cleanup(void);
 
 ia_css_ptr hmm_alloc(size_t bytes);
 ia_css_ptr hmm_create_from_userdata(size_t bytes, const void __user *userptr);
+ia_css_ptr hmm_create_from_vmalloc_buf(size_t bytes, void *vmalloc_addr);
+
 void hmm_free(ia_css_ptr ptr);
 int hmm_load(ia_css_ptr virt, void *data, unsigned int bytes);
 int hmm_store(ia_css_ptr virt, const void *data, unsigned int bytes);

drivers/staging/media/atomisp/include/hmm/hmm_bo.h

@@ -73,6 +73,7 @@
 
 enum hmm_bo_type {
 	HMM_BO_PRIVATE,
+	HMM_BO_VMALLOC,
 	HMM_BO_USER,
 	HMM_BO_LAST,
 };
@@ -207,7 +208,8 @@ int hmm_bo_allocated(struct hmm_buffer_object *bo);
  */
 int hmm_bo_alloc_pages(struct hmm_buffer_object *bo,
 		       enum hmm_bo_type type,
-		       const void __user *userptr);
+		       const void __user *userptr,
+		       void *vmalloc_addr);
 void hmm_bo_free_pages(struct hmm_buffer_object *bo);
 int hmm_bo_page_allocated(struct hmm_buffer_object *bo);
 

drivers/staging/media/atomisp/pci/hmm/hmm.c

@@ -41,11 +41,10 @@ static bool hmm_initialized;
 
 /*
  * p: private
- * s: shared
+ * v: vmalloc
  * u: user
- * i: ion
  */
-static const char hmm_bo_type_string[] = "psui";
+static const char hmm_bo_type_string[] = "pvu";
 
 static ssize_t bo_show(struct device *dev, struct device_attribute *attr,
 		       char *buf, struct list_head *bo_list, bool active)
@@ -168,7 +167,9 @@ void hmm_cleanup(void)
 	hmm_initialized = false;
 }
 
-static ia_css_ptr __hmm_alloc(size_t bytes, enum hmm_bo_type type, const void __user *userptr)
+static ia_css_ptr __hmm_alloc(size_t bytes, enum hmm_bo_type type,
+			      const void __user *userptr,
+			      void *vmalloc_addr)
 {
 	unsigned int pgnr;
 	struct hmm_buffer_object *bo;
@@ -192,7 +193,7 @@ static ia_css_ptr __hmm_alloc(size_t bytes, enum hmm_bo_type type, const void __
 	}
 
 	/* Allocate pages for memory */
-	ret = hmm_bo_alloc_pages(bo, type, userptr);
+	ret = hmm_bo_alloc_pages(bo, type, userptr, vmalloc_addr);
 	if (ret) {
 		dev_err(atomisp_dev, "hmm_bo_alloc_pages failed.\n");
 		goto alloc_page_err;
@@ -221,12 +222,17 @@ static ia_css_ptr __hmm_alloc(size_t bytes, enum hmm_bo_type type, const void __
 
 ia_css_ptr hmm_alloc(size_t bytes)
 {
-	return __hmm_alloc(bytes, HMM_BO_PRIVATE, NULL);
+	return __hmm_alloc(bytes, HMM_BO_PRIVATE, NULL, NULL);
+}
+
+ia_css_ptr hmm_create_from_vmalloc_buf(size_t bytes, void *vmalloc_addr)
+{
+	return __hmm_alloc(bytes, HMM_BO_VMALLOC, NULL, vmalloc_addr);
 }
 
 ia_css_ptr hmm_create_from_userdata(size_t bytes, const void __user *userptr)
 {
-	return __hmm_alloc(bytes, HMM_BO_USER, userptr);
+	return __hmm_alloc(bytes, HMM_BO_USER, userptr, NULL);
 }
 
 void hmm_free(ia_css_ptr virt)

drivers/staging/media/atomisp/pci/hmm/hmm_bo.c

@@ -694,18 +694,38 @@ static int alloc_user_pages(struct hmm_buffer_object *bo,
 	return -ENOMEM;
 }
 
+static int alloc_vmalloc_pages(struct hmm_buffer_object *bo, void *vmalloc_addr)
+{
+	void *vaddr = vmalloc_addr;
+	int i;
+
+	for (i = 0; i < bo->pgnr; i++) {
+		bo->pages[i] = vmalloc_to_page(vaddr);
+		if (!bo->pages[i]) {
+			dev_err(atomisp_dev, "Error could not get page %d of vmalloc buf\n", i);
+			return -ENOMEM;
+		}
+		vaddr += PAGE_SIZE;
+	}
+
+	return 0;
+}
+
 /*
  * allocate/free physical pages for the bo.
  *
  * type indicate where are the pages from. currently we have 3 types
- * of memory: HMM_BO_PRIVATE, HMM_BO_USER.
+ * of memory: HMM_BO_PRIVATE, HMM_BO_VMALLOC, HMM_BO_USER.
+ *
+ * vmalloc_addr is only valid when type is HMM_BO_VMALLOC.
  *
  * userptr is only valid when type is HMM_BO_USER, it indicates
  * the start address from user space task.
  */
 int hmm_bo_alloc_pages(struct hmm_buffer_object *bo,
 		       enum hmm_bo_type type,
-		       const void __user *userptr)
+		       const void __user *userptr,
+		       void *vmalloc_addr)
 {
 	int ret = -EINVAL;
 
@@ -720,12 +740,10 @@ int hmm_bo_alloc_pages(struct hmm_buffer_object *bo,
 		goto alloc_err;
 	}
 
-	/*
-	 * TO DO:
-	 * add HMM_BO_USER type
-	 */
 	if (type == HMM_BO_PRIVATE) {
 		ret = alloc_private_pages(bo);
+	} else if (type == HMM_BO_VMALLOC) {
+		ret = alloc_vmalloc_pages(bo, vmalloc_addr);
 	} else if (type == HMM_BO_USER) {
 		ret = alloc_user_pages(bo, userptr);
 	} else {
@@ -771,6 +789,8 @@ void hmm_bo_free_pages(struct hmm_buffer_object *bo)
 
 	if (bo->type == HMM_BO_PRIVATE)
 		free_private_bo_pages(bo);
+	else if (bo->type == HMM_BO_VMALLOC)
+		; /* No-op, nothing to do */
 	else if (bo->type == HMM_BO_USER)
 		free_user_pages(bo, bo->pgnr);
 	else