diff options
Diffstat (limited to 'drivers/gpu/drm/ttm/ttm_backup.c')
| -rw-r--r-- | drivers/gpu/drm/ttm/ttm_backup.c | 123 |
1 files changed, 82 insertions, 41 deletions
diff --git a/drivers/gpu/drm/ttm/ttm_backup.c b/drivers/gpu/drm/ttm/ttm_backup.c index 81df4cb5606b..3c067aadc52d 100644 --- a/drivers/gpu/drm/ttm/ttm_backup.c +++ b/drivers/gpu/drm/ttm/ttm_backup.c @@ -6,9 +6,10 @@ #include <drm/ttm/ttm_backup.h> #include <linux/export.h> -#include <linux/page-flags.h> #include <linux/swap.h> +#include "ttm_pool_internal.h" + /* * Need to map shmem indices to handle since a handle value * of 0 means error, following the swp_entry_t convention. @@ -68,17 +69,23 @@ int ttm_backup_copy_page(struct file *backup, struct page *dst, } /** - * ttm_backup_backup_page() - Backup a page + * ttm_backup_backup_folio() - Backup a folio * @backup: The struct backup pointer to use. - * @page: The page to back up. - * @writeback: Whether to perform immediate writeback of the page. + * @folio: The folio to back up. + * @order: The allocation order of @folio. Since TTM allocates higher-order + * pages without __GFP_COMP, folio_nr_pages(@folio) would always + * return 1; the caller must pass the true order explicitly. + * @writeback: Whether to perform immediate writeback of the folio's pages. * This may have performance implications. - * @idx: A unique integer for each page and each struct backup. + * @idx: A unique integer for the first page of the folio and each struct backup. * This allows the backup implementation to avoid managing * its address space separately. - * @page_gfp: The gfp value used when the page was allocated. - * This is used for accounting purposes. + * @folio_gfp: The gfp value used when the folio was allocated. + * Currently unused. * @alloc_gfp: The gfp to be used when allocating memory. + * @nr_pages_backed: Output. On a successful return, set to the number of + * pages actually backed up, which may be less than (1 << @order) + * if an -ENOMEM was encountered mid-folio. * * Context: If called from reclaim context, the caller needs to * assert that the shrinker gfp has __GFP_FS set, to avoid @@ -87,53 +94,87 @@ int ttm_backup_copy_page(struct file *backup, struct page *dst, * that the shrinker gfp has __GFP_IO set, since without it, * we're not allowed to start backup IO. * - * Return: A handle on success. Negative error code on failure. - * - * Note: This function could be extended to back up a folio and - * implementations would then split the folio internally if needed. - * Drawback is that the caller would then have to keep track of - * the folio size- and usage. + * Return: A handle for the first backed-up page on success (handles for + * subsequent pages follow sequentially). -ENOMEM if no pages could be backed + * up. Any other negative error code if a non-ENOMEM failure occurred; in that + * case any pages backed up so far are truncated before returning. */ s64 -ttm_backup_backup_page(struct file *backup, struct page *page, - bool writeback, pgoff_t idx, gfp_t page_gfp, - gfp_t alloc_gfp) +ttm_backup_backup_folio(struct file *backup, struct folio *folio, + unsigned int order, bool writeback, pgoff_t idx, + gfp_t folio_gfp, gfp_t alloc_gfp, + pgoff_t *nr_pages_backed) { struct address_space *mapping = backup->f_mapping; - unsigned long handle = 0; + int nr_pages = 1 << order; struct folio *to_folio; - int ret; + int ret, i; - to_folio = shmem_read_folio_gfp(mapping, idx, alloc_gfp); - if (IS_ERR(to_folio)) - return PTR_ERR(to_folio); + *nr_pages_backed = 0; - folio_mark_accessed(to_folio); - folio_lock(to_folio); - folio_mark_dirty(to_folio); - copy_highpage(folio_file_page(to_folio, idx), page); - handle = ttm_backup_shmem_idx_to_handle(idx); + for (i = 0; i < nr_pages; ) { + int to_nr, j; - if (writeback && !folio_mapped(to_folio) && - folio_clear_dirty_for_io(to_folio)) { - folio_set_reclaim(to_folio); - ret = shmem_writeout(to_folio, NULL, NULL); - if (!folio_test_writeback(to_folio)) - folio_clear_reclaim(to_folio); /* - * If writeout succeeds, it unlocks the folio. errors - * are otherwise dropped, since writeout is only best - * effort here. + * Only inject past the first subpage so *nr_pages_backed is + * always > 0 here, matching a genuine mid-compound -ENOMEM + * and driving the caller's reactive split fallback instead + * of an early, no-progress failure. */ - if (ret) + if (IS_ENABLED(CONFIG_FAULT_INJECTION) && i && + ttm_backup_fault_inject_folio()) + to_folio = ERR_PTR(-ENOMEM); + else + to_folio = shmem_read_folio_gfp(mapping, idx + i, alloc_gfp); + if (IS_ERR(to_folio)) { + int err = PTR_ERR(to_folio); + + if (err == -ENOMEM && *nr_pages_backed) + return ttm_backup_shmem_idx_to_handle(idx); + + if (*nr_pages_backed) { + shmem_truncate_range(file_inode(backup), + (loff_t)idx << PAGE_SHIFT, + ((loff_t)(idx + i) << PAGE_SHIFT) - 1); + /* + * The pages just truncated are no longer + * backed up; don't let the caller mistake + * them for valid handles. + */ + *nr_pages_backed = 0; + } + return err; + } + + to_nr = min_t(int, nr_pages - i, + folio_next_index(to_folio) - (idx + i)); + + folio_mark_accessed(to_folio); + folio_lock(to_folio); + folio_mark_dirty(to_folio); + + for (j = 0; j < to_nr; j++) + copy_highpage(folio_file_page(to_folio, idx + i + j), + folio_page(folio, i + j)); + + if (writeback && !folio_mapped(to_folio) && + folio_clear_dirty_for_io(to_folio)) { + folio_set_reclaim(to_folio); + ret = shmem_writeout(to_folio, NULL, NULL); + if (!folio_test_writeback(to_folio)) + folio_clear_reclaim(to_folio); + if (ret == AOP_WRITEPAGE_ACTIVATE) + folio_unlock(to_folio); + } else { folio_unlock(to_folio); - } else { - folio_unlock(to_folio); - } + } - folio_put(to_folio); + folio_put(to_folio); + i += to_nr; + *nr_pages_backed = i; + } - return handle; + return ttm_backup_shmem_idx_to_handle(idx); } /** |