Lines Matching full:bitmap

13  * struct iova_bitmap_map - A bitmap representing an IOVA range
15 * Main data structure for tracking mapped user pages of bitmap data.
23 * The user does not need to exact location of the bits in the bitmap.
25 * records the IOVA *range* in the bitmap by setting the corresponding
28 * The bitmap is an array of u64 whereas each bit represents an IOVA of
29 * range of (1 << pgshift). Thus formula for the bitmap data to be set is:
46 /* pinned pages representing the bitmap data */
51 * struct iova_bitmap - The IOVA bitmap object
53 * Main data structure for iterating over the bitmap data.
56 * It uses a windowing scheme and pins the bitmap in relatively
59 * The bitmap object uses one base page to store all the pinned pages
60 * pointers related to the bitmap. For sizeof(struct page*) == 8 it stores
62 * 2M of bitmap data is pinned at a time. If the iova_bitmap page size is
71 * An example of the APIs on how to use/iterate over the IOVA bitmap:
73 * bitmap = iova_bitmap_alloc(iova, length, page_size, data);
74 * if (IS_ERR(bitmap))
75 * return PTR_ERR(bitmap);
77 * ret = iova_bitmap_for_each(bitmap, arg, dirty_reporter_fn);
79 * iova_bitmap_free(bitmap);
86 * iova_bitmap_set(bitmap, iova, iova_length);
89 * which u64 word of the bitmap is mapped, up to @mapped_total_index.
93 * The IOVA bitmap is usually located on what tracks DMA mapped ranges or
95 * bitmap.
98 /* IOVA range representing the currently mapped bitmap data */
101 /* userspace address of the bitmap */
102 u64 __user *bitmap; member
110 /* base IOVA of the whole bitmap */
113 /* length of the IOVA range for the whole bitmap */
118 * Converts a relative IOVA to a bitmap index.
119 * This function provides the index into the u64 array (bitmap::bitmap)
121 * Relative IOVA means relative to the bitmap::mapped base IOVA
126 static unsigned long iova_bitmap_offset_to_index(struct iova_bitmap *bitmap, in iova_bitmap_offset_to_index() argument
129 unsigned long pgsize = 1 << bitmap->mapped.pgshift; in iova_bitmap_offset_to_index()
131 return iova / (BITS_PER_TYPE(*bitmap->bitmap) * pgsize); in iova_bitmap_offset_to_index()
135 * Converts a bitmap index to a *relative* IOVA.
137 static unsigned long iova_bitmap_index_to_offset(struct iova_bitmap *bitmap, in iova_bitmap_index_to_offset() argument
140 unsigned long pgshift = bitmap->mapped.pgshift; in iova_bitmap_index_to_offset()
142 return (index * BITS_PER_TYPE(*bitmap->bitmap)) << pgshift; in iova_bitmap_index_to_offset()
148 static unsigned long iova_bitmap_mapped_iova(struct iova_bitmap *bitmap) in iova_bitmap_mapped_iova() argument
150 unsigned long skip = bitmap->mapped_base_index; in iova_bitmap_mapped_iova()
152 return bitmap->iova + iova_bitmap_index_to_offset(bitmap, skip); in iova_bitmap_mapped_iova()
156 * Pins the bitmap user pages for the current range window.
157 * This is internal to IOVA bitmap and called when advancing the
158 * index (@mapped_base_index) or allocating the bitmap.
160 static int iova_bitmap_get(struct iova_bitmap *bitmap) in iova_bitmap_get() argument
162 struct iova_bitmap_map *mapped = &bitmap->mapped; in iova_bitmap_get()
173 npages = DIV_ROUND_UP((bitmap->mapped_total_index - in iova_bitmap_get()
174 bitmap->mapped_base_index) * in iova_bitmap_get()
175 sizeof(*bitmap->bitmap), PAGE_SIZE); in iova_bitmap_get()
179 * This is, for example, on x86 means 2M of bitmap data max. in iova_bitmap_get()
184 * Bitmap address to be pinned is calculated via pointer arithmetic in iova_bitmap_get()
185 * with bitmap u64 word index. in iova_bitmap_get()
187 addr = bitmap->bitmap + bitmap->mapped_base_index; in iova_bitmap_get()
196 mapped->iova = iova_bitmap_mapped_iova(bitmap); in iova_bitmap_get()
200 * This handles the case where the bitmap is not PAGE_SIZE in iova_bitmap_get()
208 * Unpins the bitmap user pages and clears @npages
210 * the index or freeing the bitmap.
212 static void iova_bitmap_put(struct iova_bitmap *bitmap) in iova_bitmap_put() argument
214 struct iova_bitmap_map *mapped = &bitmap->mapped; in iova_bitmap_put()
223 * iova_bitmap_alloc() - Allocates an IOVA bitmap object
226 * @page_size: Page size of the IOVA bitmap. It defines what each bit
228 * @data: Userspace address of the bitmap
240 struct iova_bitmap *bitmap; in iova_bitmap_alloc() local
243 bitmap = kzalloc(sizeof(*bitmap), GFP_KERNEL); in iova_bitmap_alloc()
244 if (!bitmap) in iova_bitmap_alloc()
247 mapped = &bitmap->mapped; in iova_bitmap_alloc()
249 bitmap->bitmap = data; in iova_bitmap_alloc()
250 bitmap->mapped_total_index = in iova_bitmap_alloc()
251 iova_bitmap_offset_to_index(bitmap, length - 1) + 1; in iova_bitmap_alloc()
252 bitmap->iova = iova; in iova_bitmap_alloc()
253 bitmap->length = length; in iova_bitmap_alloc()
261 rc = iova_bitmap_get(bitmap); in iova_bitmap_alloc()
264 return bitmap; in iova_bitmap_alloc()
267 iova_bitmap_free(bitmap); in iova_bitmap_alloc()
272 * iova_bitmap_free() - Frees an IOVA bitmap object
273 * @bitmap: IOVA bitmap to free
278 void iova_bitmap_free(struct iova_bitmap *bitmap) in iova_bitmap_free() argument
280 struct iova_bitmap_map *mapped = &bitmap->mapped; in iova_bitmap_free()
282 iova_bitmap_put(bitmap); in iova_bitmap_free()
289 kfree(bitmap); in iova_bitmap_free()
293 * Returns the remaining bitmap indexes from mapped_total_index to process for
294 * the currently pinned bitmap pages.
296 static unsigned long iova_bitmap_mapped_remaining(struct iova_bitmap *bitmap) in iova_bitmap_mapped_remaining() argument
300 remaining = bitmap->mapped_total_index - bitmap->mapped_base_index; in iova_bitmap_mapped_remaining()
302 (bitmap->mapped.npages << PAGE_SHIFT) / sizeof(*bitmap->bitmap)); in iova_bitmap_mapped_remaining()
310 static unsigned long iova_bitmap_mapped_length(struct iova_bitmap *bitmap) in iova_bitmap_mapped_length() argument
312 unsigned long max_iova = bitmap->iova + bitmap->length - 1; in iova_bitmap_mapped_length()
313 unsigned long iova = iova_bitmap_mapped_iova(bitmap); in iova_bitmap_mapped_length()
318 * when converted to IOVA gives us a max length that the bitmap in iova_bitmap_mapped_length()
320 * only cover the IOVA range in @bitmap::iova .. @bitmap::length. in iova_bitmap_mapped_length()
322 remaining = iova_bitmap_index_to_offset(bitmap, in iova_bitmap_mapped_length()
323 iova_bitmap_mapped_remaining(bitmap)); in iova_bitmap_mapped_length()
334 static bool iova_bitmap_done(struct iova_bitmap *bitmap) in iova_bitmap_done() argument
336 return bitmap->mapped_base_index >= bitmap->mapped_total_index; in iova_bitmap_done()
341 * pages and pins the next set of bitmap pages.
344 static int iova_bitmap_advance(struct iova_bitmap *bitmap) in iova_bitmap_advance() argument
346 unsigned long iova = iova_bitmap_mapped_length(bitmap) - 1; in iova_bitmap_advance()
347 unsigned long count = iova_bitmap_offset_to_index(bitmap, iova) + 1; in iova_bitmap_advance()
349 bitmap->mapped_base_index += count; in iova_bitmap_advance()
351 iova_bitmap_put(bitmap); in iova_bitmap_advance()
352 if (iova_bitmap_done(bitmap)) in iova_bitmap_advance()
355 /* When advancing the index we pin the next set of bitmap pages */ in iova_bitmap_advance()
356 return iova_bitmap_get(bitmap); in iova_bitmap_advance()
360 * iova_bitmap_for_each() - Iterates over the bitmap
361 * @bitmap: IOVA bitmap to iterate
365 * Helper function to iterate over bitmap data representing a portion of IOVA
367 * mapped bitmap user pages into IOVA ranges to process.
372 int iova_bitmap_for_each(struct iova_bitmap *bitmap, void *opaque, in iova_bitmap_for_each() argument
377 for (; !iova_bitmap_done(bitmap) && !ret; in iova_bitmap_for_each()
378 ret = iova_bitmap_advance(bitmap)) { in iova_bitmap_for_each()
379 ret = fn(bitmap, iova_bitmap_mapped_iova(bitmap), in iova_bitmap_for_each()
380 iova_bitmap_mapped_length(bitmap), opaque); in iova_bitmap_for_each()
389 * iova_bitmap_set() - Records an IOVA range in bitmap
390 * @bitmap: IOVA bitmap
395 * the user bitmap.
399 void iova_bitmap_set(struct iova_bitmap *bitmap, in iova_bitmap_set() argument
402 struct iova_bitmap_map *mapped = &bitmap->mapped; in iova_bitmap_set()