From 89f4b4c53a7c12d2feec0ecaa15b0493b2bd61e6 Mon Sep 17 00:00:00 2001 From: Jani Nikula Date: Wed, 29 Jun 2022 12:27:53 +0300 Subject: [PATCH] drm/edid: do invalid block filtering in-place MIME-Version: 1.0 Content-Type: text/plain; charset=utf8 Content-Transfer-Encoding: 8bit Rewrite edid_filter_invalid_blocks() to filter invalid blocks in-place. The main motivation is to not rely on passed in information on invalid block count or the allocation size, which will be helpful in follow-up work on HF-EEODB. Signed-off-by: Jani Nikula Reviewed-by: Ville Syrjälä Link: https://patchwork.freedesktop.org/patch/msgid/a6ad5e4e7b91338c0d19d7be189af31094e65555.1656494768.git.jani.nikula@intel.com --- drivers/gpu/drm/drm_edid.c | 43 +++++++++++++++++++++++-------------------- 1 file changed, 23 insertions(+), 20 deletions(-) diff --git a/drivers/gpu/drm/drm_edid.c b/drivers/gpu/drm/drm_edid.c index 1c761e1..a80ea0a 100644 --- a/drivers/gpu/drm/drm_edid.c +++ b/drivers/gpu/drm/drm_edid.c @@ -2020,33 +2020,37 @@ bool drm_edid_is_valid(struct edid *edid) } EXPORT_SYMBOL(drm_edid_is_valid); -static struct edid *edid_filter_invalid_blocks(const struct edid *edid, - int invalid_blocks, +static struct edid *edid_filter_invalid_blocks(struct edid *edid, size_t *alloc_size) { - struct edid *new, *dest_block; - int valid_extensions = edid->extensions - invalid_blocks; - int i; + struct edid *new; + int i, valid_blocks = 0; - *alloc_size = edid_size_by_blocks(valid_extensions + 1); + for (i = 0; i < edid_block_count(edid); i++) { + const void *src_block = edid_block_data(edid, i); - new = kmalloc(*alloc_size, GFP_KERNEL); - if (!new) - goto out; + if (edid_block_valid(src_block, i == 0)) { + void *dst_block = (void *)edid_block_data(edid, valid_blocks); - dest_block = new; - for (i = 0; i < edid_block_count(edid); i++) { - const void *block = edid_block_data(edid, i); + memmove(dst_block, src_block, EDID_LENGTH); + valid_blocks++; + } + } - if (edid_block_valid(block, i == 0)) - memcpy(dest_block++, block, EDID_LENGTH); + /* We already trusted the base block to be valid here... */ + if (WARN_ON(!valid_blocks)) { + kfree(edid); + return NULL; } - new->extensions = valid_extensions; - new->checksum = edid_block_compute_checksum(new); + edid->extensions = valid_blocks - 1; + edid->checksum = edid_block_compute_checksum(edid); -out: - kfree(edid); + *alloc_size = edid_size_by_blocks(valid_blocks); + + new = krealloc(edid, *alloc_size, GFP_KERNEL); + if (!new) + kfree(edid); return new; } @@ -2316,8 +2320,7 @@ static struct edid *_drm_do_get_edid(struct drm_connector *connector, if (invalid_blocks) { connector_bad_edid(connector, edid, edid_block_count(edid)); - edid = edid_filter_invalid_blocks(edid, invalid_blocks, - &alloc_size); + edid = edid_filter_invalid_blocks(edid, &alloc_size); } ok: -- 2.7.4