[PATCH v6 1/5] block: Add alternative_gpt_sector() operation

From: Dmitry Osipenko <digetx@gmail.com>
To: "Jens Axboe" <axboe@kernel.dk>,
	"Thierry Reding" <thierry.reding@gmail.com>,
	"Jonathan Hunter" <jonathanh@nvidia.com>,
	"Michał Mirosław" <mirq-linux@rere.qmqm.pl>,
	"David Heidelberg" <david@ixit.cz>,
	"Peter Geis" <pgwipeout@gmail.com>,
	"Ulf Hansson" <ulf.hansson@linaro.org>,
	"Adrian Hunter" <adrian.hunter@intel.com>,
	"Christoph Hellwig" <hch@infradead.org>,
	"Davidlohr Bueso" <dave@stgolabs.net>,
	"Rob Herring" <robh+dt@kernel.org>,
	"Ion Agorria" <AG0RRIA@yahoo.com>,
	"Svyatoslav Ryhel" <clamor95@gmail.com>
Cc: linux-tegra@vger.kernel.org, linux-block@vger.kernel.org,
	linux-efi <linux-efi@vger.kernel.org>
Subject: [PATCH v6 1/5] block: Add alternative_gpt_sector() operation
Date: Thu, 19 Aug 2021 01:19:16 +0300	[thread overview]
Message-ID: <20210818221920.3893-2-digetx@gmail.com> (raw)
In-Reply-To: <20210818221920.3893-1-digetx@gmail.com>

Add alternative_gpt_sector() block device operation which specifies
alternative location of a GPT entry. This allows us to support Android
devices that have GPT entry at a non-standard location and can't be
repartitioned easily.

Suggested-by: Christoph Hellwig <hch@infradead.org>
Signed-off-by: Dmitry Osipenko <digetx@gmail.com>
---
 include/linux/blkdev.h | 7 +++++++
 1 file changed, 7 insertions(+)

diff --git a/include/linux/blkdev.h b/include/linux/blkdev.h
index 111a3911c4d2..d65c8f60ad8e 100644
--- a/include/linux/blkdev.h
+++ b/include/linux/blkdev.h
@@ -1850,6 +1850,13 @@ struct block_device_operations {
 	char *(*devnode)(struct gendisk *disk, umode_t *mode);
 	struct module *owner;
 	const struct pr_ops *pr_ops;
+
+	/*
+	 * Special callback for probing GPT entry at a given sector.
+	 * Needed by Android devices, used by GPT scanner and MMC blk
+	 * driver.
+	 */
+	int (*alternative_gpt_sector)(struct gendisk *disk, sector_t *sector);
 };
 
 #ifdef CONFIG_COMPAT
-- 
2.32.0

