From: Thomas Hellström thomas.hellstrom@linux.intel.com
[ Upstream commit 379989e7cbdc7aa7496a00ee286ec146c7599cf0 ]
When hitting an error, the error path forgot to unmap dma mappings and could call set_pages_wb() on already uncached pages.
Fix this by introducing a common ttm_pool_free_range() function that does the right thing.
v2: - Simplify that common function (Christian König) v3: - Rename that common function to ttm_pool_free_range() (Christian König)
Fixes: d099fc8f540a ("drm/ttm: new TT backend allocation pool v3") Cc: Christian König christian.koenig@amd.com Cc: Dave Airlie airlied@redhat.com Cc: Christian Koenig christian.koenig@amd.com Cc: Huang Rui ray.huang@amd.com Cc: dri-devel@lists.freedesktop.org Signed-off-by: Thomas Hellström thomas.hellstrom@linux.intel.com Reviewed-by: Christian König christian.koenig@amd.com Link: https://patchwork.freedesktop.org/patch/msgid/20230404200650.11043-2-thomas.... Signed-off-by: Sasha Levin sashal@kernel.org --- drivers/gpu/drm/ttm/ttm_pool.c | 81 +++++++++++++++++++++------------- 1 file changed, 51 insertions(+), 30 deletions(-)
diff --git a/drivers/gpu/drm/ttm/ttm_pool.c b/drivers/gpu/drm/ttm/ttm_pool.c index 603b044833048..aa3512af051ad 100644 --- a/drivers/gpu/drm/ttm/ttm_pool.c +++ b/drivers/gpu/drm/ttm/ttm_pool.c @@ -367,6 +367,43 @@ static int ttm_pool_page_allocated(struct ttm_pool *pool, unsigned int order, return 0; }
+/** + * ttm_pool_free_range() - Free a range of TTM pages + * @pool: The pool used for allocating. + * @tt: The struct ttm_tt holding the page pointers. + * @caching: The page caching mode used by the range. + * @start_page: index for first page to free. + * @end_page: index for last page to free + 1. + * + * During allocation the ttm_tt page-vector may be populated with ranges of + * pages with different attributes if allocation hit an error without being + * able to completely fulfill the allocation. This function can be used + * to free these individual ranges. + */ +static void ttm_pool_free_range(struct ttm_pool *pool, struct ttm_tt *tt, + enum ttm_caching caching, + pgoff_t start_page, pgoff_t end_page) +{ + struct page **pages = tt->pages; + unsigned int order; + pgoff_t i, nr; + + for (i = start_page; i < end_page; i += nr, pages += nr) { + struct ttm_pool_type *pt = NULL; + + order = ttm_pool_page_order(pool, *pages); + nr = (1UL << order); + if (tt->dma_address) + ttm_pool_unmap(pool, tt->dma_address[i], nr); + + pt = ttm_pool_select_type(pool, caching, order); + if (pt) + ttm_pool_type_give(pt, *pages); + else + ttm_pool_free_page(pool, caching, order, *pages); + } +} + /** * ttm_pool_alloc - Fill a ttm_tt object * @@ -382,12 +419,14 @@ static int ttm_pool_page_allocated(struct ttm_pool *pool, unsigned int order, int ttm_pool_alloc(struct ttm_pool *pool, struct ttm_tt *tt, struct ttm_operation_ctx *ctx) { - unsigned long num_pages = tt->num_pages; + pgoff_t num_pages = tt->num_pages; dma_addr_t *dma_addr = tt->dma_address; struct page **caching = tt->pages; struct page **pages = tt->pages; + enum ttm_caching page_caching; gfp_t gfp_flags = GFP_USER; - unsigned int i, order; + pgoff_t caching_divide; + unsigned int order; struct page *p; int r;
@@ -410,6 +449,7 @@ int ttm_pool_alloc(struct ttm_pool *pool, struct ttm_tt *tt, order = min_t(unsigned int, order, __fls(num_pages))) { struct ttm_pool_type *pt;
+ page_caching = tt->caching; pt = ttm_pool_select_type(pool, tt->caching, order); p = pt ? ttm_pool_type_take(pt) : NULL; if (p) { @@ -418,6 +458,7 @@ int ttm_pool_alloc(struct ttm_pool *pool, struct ttm_tt *tt, if (r) goto error_free_page;
+ caching = pages; do { r = ttm_pool_page_allocated(pool, order, p, &dma_addr, @@ -426,14 +467,15 @@ int ttm_pool_alloc(struct ttm_pool *pool, struct ttm_tt *tt, if (r) goto error_free_page;
+ caching = pages; if (num_pages < (1 << order)) break;
p = ttm_pool_type_take(pt); } while (p); - caching = pages; }
+ page_caching = ttm_cached; while (num_pages >= (1 << order) && (p = ttm_pool_alloc_page(pool, gfp_flags, order))) {
@@ -442,6 +484,7 @@ int ttm_pool_alloc(struct ttm_pool *pool, struct ttm_tt *tt, tt->caching); if (r) goto error_free_page; + caching = pages; } r = ttm_pool_page_allocated(pool, order, p, &dma_addr, &num_pages, &pages); @@ -468,15 +511,13 @@ int ttm_pool_alloc(struct ttm_pool *pool, struct ttm_tt *tt, return 0;
error_free_page: - ttm_pool_free_page(pool, tt->caching, order, p); + ttm_pool_free_page(pool, page_caching, order, p);
error_free_all: num_pages = tt->num_pages - num_pages; - for (i = 0; i < num_pages; ) { - order = ttm_pool_page_order(pool, tt->pages[i]); - ttm_pool_free_page(pool, tt->caching, order, tt->pages[i]); - i += 1 << order; - } + caching_divide = caching - tt->pages; + ttm_pool_free_range(pool, tt, tt->caching, 0, caching_divide); + ttm_pool_free_range(pool, tt, ttm_cached, caching_divide, num_pages);
return r; } @@ -492,27 +533,7 @@ EXPORT_SYMBOL(ttm_pool_alloc); */ void ttm_pool_free(struct ttm_pool *pool, struct ttm_tt *tt) { - unsigned int i; - - for (i = 0; i < tt->num_pages; ) { - struct page *p = tt->pages[i]; - unsigned int order, num_pages; - struct ttm_pool_type *pt; - - order = ttm_pool_page_order(pool, p); - num_pages = 1ULL << order; - if (tt->dma_address) - ttm_pool_unmap(pool, tt->dma_address[i], num_pages); - - pt = ttm_pool_select_type(pool, tt->caching, order); - if (pt) - ttm_pool_type_give(pt, tt->pages[i]); - else - ttm_pool_free_page(pool, tt->caching, order, - tt->pages[i]); - - i += num_pages; - } + ttm_pool_free_range(pool, tt, tt->caching, 0, tt->num_pages);
while (atomic_long_read(&allocated_pages) > page_pool_size) ttm_pool_shrink();