From 367f2b9568e03ad8ccb637a8f53623bf5eab4b7c Mon Sep 17 00:00:00 2001 From: Aaron Durbin Date: Fri, 5 Aug 2016 15:41:37 -0500 Subject: drivers/elog: consolidate checks in elog_find_flash() There were checks against global variables trying to determine failing cases of elog_find_flash(). Instead move the checks into elog_find_flash() and return value indicating failure. A minimum 4KiB check was added to ensure the eventlog is at least that size which makes the heuristic checks cleaner. BUG=chrome-os-partner:55932 Change-Id: I4d9d13148555e05d4f217a10f995831a0e437fc3 Signed-off-by: Aaron Durbin Reviewed-on: https://review.coreboot.org/16101 Tested-by: build bot (Jenkins) Reviewed-by: Martin Roth --- src/drivers/elog/elog.c | 40 +++++++++++++++++++++------------------- 1 file changed, 21 insertions(+), 19 deletions(-) diff --git a/src/drivers/elog/elog.c b/src/drivers/elog/elog.c index 036ab91493..ea7597fee8 100644 --- a/src/drivers/elog/elog.c +++ b/src/drivers/elog/elog.c @@ -622,7 +622,7 @@ int elog_clear(void) return elog_prepare_empty(); } -static void elog_find_flash(void) +static int elog_find_flash(void) { struct region r; size_t reserved_space = ELOG_MIN_AVAILABLE_ENTRIES * MAX_EVENT_SIZE; @@ -632,16 +632,28 @@ static void elog_find_flash(void) /* Find the ELOG base and size in FMAP */ if (fmap_locate_area("RW_ELOG", &r) < 0) { printk(BIOS_WARNING, "ELOG: Unable to find RW_ELOG in FMAP\n"); - flash_base = total_size = 0; - } else { - flash_base = region_offset(&r); - /* Keep 4KiB max size until large malloc()s have been fixed. */ - total_size = MIN(4*KiB, region_sz(&r)); + return -1; + } + + if (region_sz(&r) < 4*KiB) { + printk(BIOS_WARNING, "ELOG: Needs a minium size of 4KiB: %zu\n", + region_sz(&r)); + return -1; } + flash_base = region_offset(&r); + /* Keep 4KiB max size until large malloc()s have been fixed. */ + total_size = MIN(4*KiB, region_sz(&r)); + full_threshold = total_size - reserved_space; - shrink_size = MIN(total_size * ELOG_SHRINK_PERCENTAGE / 100, - full_threshold); + shrink_size = total_size * ELOG_SHRINK_PERCENTAGE / 100; + + if (reserved_space > shrink_size) { + printk(BIOS_ERR, "ELOG: SHRINK_PERCENTAGE too small\n"); + return -1; + } + + return 0; } static int elog_sync_to_nv(void) @@ -711,18 +723,8 @@ int elog_init(void) } /* Set up the backing store */ - elog_find_flash(); - if (flash_base == 0) { - printk(BIOS_ERR, "ELOG: Invalid flash base\n"); + if (elog_find_flash() < 0) return -1; - } else if (total_size < sizeof(struct elog_header) + MAX_EVENT_SIZE) { - printk(BIOS_ERR, "ELOG: Region too small to hold any events\n"); - return -1; - } else if (total_size - shrink_size >= full_threshold) { - printk(BIOS_ERR, - "ELOG: SHRINK_PERCENTAGE set too small for MIN_AVAILABLE_ENTRIES\n"); - return -1; - } mirror_buffer = malloc(total_size); if (!mirror_buffer) { -- cgit v1.2.3