From 601e1b270fded69c8d1265a14c80d70f5e200e7b Mon Sep 17 00:00:00 2001 From: jsg Date: Fri, 12 May 2023 11:19:12 +0000 Subject: [PATCH] drm/ttm/pool: Fix ttm_pool_alloc error path From Thomas Hellstrom d2151c5d9dbe3f8fec4cae5f4784edce3ced3a7e in linux-6.1.y/6.1.28 379989e7cbdc7aa7496a00ee286ec146c7599cf0 in mainline linux --- sys/dev/pci/drm/ttm/ttm_pool.c | 82 +++++++++++++++++++++------------- 1 file changed, 52 insertions(+), 30 deletions(-) diff --git a/sys/dev/pci/drm/ttm/ttm_pool.c b/sys/dev/pci/drm/ttm/ttm_pool.c index 799112bec2b..8ed9fe8e19a 100644 --- a/sys/dev/pci/drm/ttm/ttm_pool.c +++ b/sys/dev/pci/drm/ttm/ttm_pool.c @@ -510,6 +510,43 @@ 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 vm_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 = tt->orders[i]; + 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 * @@ -525,15 +562,17 @@ 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 vm_page **caching = tt->pages; struct vm_page **pages = tt->pages; - unsigned long *orders = tt->orders; + enum ttm_caching page_caching; gfp_t gfp_flags = GFP_USER; - unsigned int i, order; + pgoff_t caching_divide; + unsigned int order; struct vm_page *p; int r; + unsigned long *orders = tt->orders; WARN_ON(!num_pages || ttm_tt_is_populated(tt)); #ifdef __linux__ @@ -556,6 +595,7 @@ 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) { @@ -564,6 +604,7 @@ 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, @@ -572,14 +613,15 @@ 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, tt->dmat))) { @@ -588,6 +630,7 @@ 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, &orders); @@ -614,15 +657,13 @@ 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 = tt->orders[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; } @@ -638,26 +679,7 @@ 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; ) { - unsigned int order, num_pages; - struct ttm_pool_type *pt; - - order = tt->orders[i]; - 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(); -- 2.20.1