From a12a5cb5b821f24f26d388094cdac79deb0e879f Mon Sep 17 00:00:00 2001
From: Brian Behlendorf <behlendorf1@llnl.gov>
Date: Fri, 27 May 2022 19:40:22 +0000
Subject: [PATCH] Linux 5.19 compat: blkdev_issue_secure_erase()

Linux 5.19 commit torvalds/linux@44abff2c0 splits the secure
erase functionality from the blkdev_issue_discard() function.
The blkdev_issue_secure_erase() must now be issued to issue
a secure erase.

Reviewed-by: Tony Hutter <hutter2@llnl.gov>
Signed-off-by: Brian Behlendorf <behlendorf1@llnl.gov>
Closes #13515
---
 config/kernel-blkdev.m4         | 53 +++++++++++++++++++++++++++++++++
 module/os/linux/zfs/vdev_disk.c | 37 +++++++++++++++++------
 2 files changed, 81 insertions(+), 9 deletions(-)

diff --git a/config/kernel-blkdev.m4 b/config/kernel-blkdev.m4
index 9c60e5dd4..fb7b1a458 100644
--- a/config/kernel-blkdev.m4
+++ b/config/kernel-blkdev.m4
@@ -294,6 +294,57 @@ AC_DEFUN([ZFS_AC_KERNEL_BLKDEV_BDEV_WHOLE], [
 	])
 ])
 
+dnl #
+dnl # 5.19 API: blkdev_issue_secure_erase()
+dnl # 3.10 API: blkdev_issue_discard(..., BLKDEV_DISCARD_SECURE)
+dnl #
+AC_DEFUN([ZFS_AC_KERNEL_SRC_BLKDEV_ISSUE_SECURE_ERASE], [
+	ZFS_LINUX_TEST_SRC([blkdev_issue_secure_erase], [
+		#include <linux/blkdev.h>
+	],[
+		struct block_device *bdev = NULL;
+		sector_t sector = 0;
+		sector_t nr_sects = 0;
+		int error __attribute__ ((unused));
+
+		error = blkdev_issue_secure_erase(bdev,
+		    sector, nr_sects, GFP_KERNEL);
+	])
+
+	ZFS_LINUX_TEST_SRC([blkdev_issue_discard_flags], [
+		#include <linux/blkdev.h>
+	],[
+		struct block_device *bdev = NULL;
+		sector_t sector = 0;
+		sector_t nr_sects = 0;
+		unsigned long flags = 0;
+		int error __attribute__ ((unused));
+
+		error = blkdev_issue_discard(bdev,
+		    sector, nr_sects, GFP_KERNEL, flags);
+	])
+])
+
+AC_DEFUN([ZFS_AC_KERNEL_BLKDEV_ISSUE_SECURE_ERASE], [
+	AC_MSG_CHECKING([whether blkdev_issue_secure_erase() is available])
+	ZFS_LINUX_TEST_RESULT([blkdev_issue_secure_erase], [
+		AC_MSG_RESULT(yes)
+		AC_DEFINE(HAVE_BLKDEV_ISSUE_SECURE_ERASE, 1,
+		    [blkdev_issue_secure_erase() is available])
+	],[
+		AC_MSG_RESULT(no)
+
+		AC_MSG_CHECKING([whether blkdev_issue_discard() is available])
+		ZFS_LINUX_TEST_RESULT([blkdev_issue_discard_flags], [
+			AC_MSG_RESULT(yes)
+			AC_DEFINE(HAVE_BLKDEV_ISSUE_DISCARD, 1,
+			    [blkdev_issue_discard() is available])
+		],[
+			ZFS_LINUX_TEST_ERROR([blkdev_issue_discard()])
+		])
+	])
+])
+
 dnl #
 dnl # 5.13 API change
 dnl # blkdev_get_by_path() no longer handles ERESTARTSYS
@@ -326,6 +377,7 @@ AC_DEFUN([ZFS_AC_KERNEL_SRC_BLKDEV], [
 	ZFS_AC_KERNEL_SRC_BLKDEV_CHECK_DISK_CHANGE
 	ZFS_AC_KERNEL_SRC_BLKDEV_BDEV_CHECK_MEDIA_CHANGE
 	ZFS_AC_KERNEL_SRC_BLKDEV_BDEV_WHOLE
+	ZFS_AC_KERNEL_SRC_BLKDEV_ISSUE_SECURE_ERASE
 ])
 
 AC_DEFUN([ZFS_AC_KERNEL_BLKDEV], [
@@ -340,4 +392,5 @@ AC_DEFUN([ZFS_AC_KERNEL_BLKDEV], [
 	ZFS_AC_KERNEL_BLKDEV_BDEV_CHECK_MEDIA_CHANGE
 	ZFS_AC_KERNEL_BLKDEV_BDEV_WHOLE
 	ZFS_AC_KERNEL_BLKDEV_GET_ERESTARTSYS
+	ZFS_AC_KERNEL_BLKDEV_ISSUE_SECURE_ERASE
 ])
diff --git a/module/os/linux/zfs/vdev_disk.c b/module/os/linux/zfs/vdev_disk.c
index 5d87e9211..9a382261d 100644
--- a/module/os/linux/zfs/vdev_disk.c
+++ b/module/os/linux/zfs/vdev_disk.c
@@ -751,12 +751,38 @@ vdev_disk_io_flush(struct block_device *bdev, zio_t *zio)
 	return (0);
 }
 
+static int
+vdev_disk_io_trim(zio_t *zio)
+{
+	vdev_t *v = zio->io_vd;
+	vdev_disk_t *vd = v->vdev_tsd;
+
+#if defined(HAVE_BLKDEV_ISSUE_SECURE_ERASE)
+	if (zio->io_trim_flags & ZIO_TRIM_SECURE) {
+		return (-blkdev_issue_secure_erase(vd->vd_bdev,
+		    zio->io_offset >> 9, zio->io_size >> 9, GFP_NOFS));
+	} else {
+		return (-blkdev_issue_discard(vd->vd_bdev,
+		    zio->io_offset >> 9, zio->io_size >> 9, GFP_NOFS));
+	}
+#elif defined(HAVE_BLKDEV_ISSUE_DISCARD)
+	unsigned long trim_flags = 0;
+#if defined(BLKDEV_DISCARD_SECURE)
+	if (zio->io_trim_flags & ZIO_TRIM_SECURE)
+		trim_flags |= BLKDEV_DISCARD_SECURE;
+#endif
+	return (-blkdev_issue_discard(vd->vd_bdev,
+	    zio->io_offset >> 9, zio->io_size >> 9, GFP_NOFS, trim_flags));
+#else
+#error "Unsupported kernel"
+#endif
+}
+
 static void
 vdev_disk_io_start(zio_t *zio)
 {
 	vdev_t *v = zio->io_vd;
 	vdev_disk_t *vd = v->vdev_tsd;
-	unsigned long trim_flags = 0;
 	int rw, error;
 
 	/*
@@ -829,14 +855,7 @@ vdev_disk_io_start(zio_t *zio)
 		break;
 
 	case ZIO_TYPE_TRIM:
-#if defined(BLKDEV_DISCARD_SECURE)
-		if (zio->io_trim_flags & ZIO_TRIM_SECURE)
-			trim_flags |= BLKDEV_DISCARD_SECURE;
-#endif
-		zio->io_error = -blkdev_issue_discard(vd->vd_bdev,
-		    zio->io_offset >> 9, zio->io_size >> 9, GFP_NOFS,
-		    trim_flags);
-
+		zio->io_error = vdev_disk_io_trim(zio);
 		rw_exit(&vd->vd_lock);
 		zio_interrupt(zio);
 		return;