partitions/efi: Support non-standard GPT location

Support looking up GPT at a non-standard location specified by a block
device driver.

Acked-by: Davidlohr Bueso <dbueso@suse.de>
Reviewed-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Dmitry Osipenko <digetx@gmail.com>
Reviewed-by: Ulf Hansson <ulf.hansson@linaro.org>
Link: https://lore.kernel.org/r/20210820004536.15791-3-digetx@gmail.com
Signed-off-by: Jens Axboe <axboe@kernel.dk>
This commit is contained in:
Dmitry Osipenko 2021-08-20 03:45:34 +03:00 committed by Jens Axboe
parent 0bdfbca8a6
commit 466d9c4904

View File

@ -585,6 +585,8 @@ static int find_valid_gpt(struct parsed_partitions *state, gpt_header **gpt,
gpt_header *pgpt = NULL, *agpt = NULL;
gpt_entry *pptes = NULL, *aptes = NULL;
legacy_mbr *legacymbr;
struct gendisk *disk = state->disk;
const struct block_device_operations *fops = disk->fops;
sector_t total_sectors = get_capacity(state->disk);
u64 lastlba;
@ -619,6 +621,16 @@ static int find_valid_gpt(struct parsed_partitions *state, gpt_header **gpt,
if (!good_agpt && force_gpt)
good_agpt = is_gpt_valid(state, lastlba, &agpt, &aptes);
if (!good_agpt && force_gpt && fops->alternative_gpt_sector) {
sector_t agpt_sector;
int err;
err = fops->alternative_gpt_sector(disk, &agpt_sector);
if (!err)
good_agpt = is_gpt_valid(state, agpt_sector,
&agpt, &aptes);
}
/* The obviously unsuccessful case */
if (!good_pgpt && !good_agpt)
goto fail;