virtio_blk: set the zone write granularitygrafted

virtblk_read_zoned_limits() reads the write granularity that the device
reports in virtio_blk_zoned_characteristics and assigns it to the
physical block size and to io_min, but never to the limit that is named
after it. queue_limits.zone_write_granularity is left at zero, so
blk_validate_zoned_limits() raises it to the logical block size:

	if (lim->zone_write_granularity < lim->logical_block_size)
		lim->zone_write_granularity = lim->logical_block_size;

A device that reports a granularity coarser than its logical block size,
which is what the field exists to express, therefore has it silently
reduced. A 512e host managed disk passed through to a guest reports a
logical block size of 512 and a write granularity of 4096, and the guest
ends up with a zone write granularity of 512.

bio_split_alignment() returns lim->zone_write_granularity if it is non-zero
and bio_split_io_at() may split a bio with as per bio_split_alignment().
This can real to the write getting rejected by the host drive, as the write
is not aligned to the physical block size.

zonefs also takes its block size from bdev_zone_write_granularity(), so it
would incorrectly use 512 on a disk that requires 4096.

sd_zbc_read_zones() sets the limit from the physical block size for the
same reason. NVMe ZNS and null_blk leave it unset, but the fallback
gives the right answer for them, as their write granularity is the
logical block size. virtio carries a separate value that may exceed it.

Set the zone write granularity from the value that the device reports.

Fixes: 95bfec41bd3d ("virtio-blk: add support for zoned block devices")
Signed-off-by: Niklas Cassel <cassel@kernel.org>
Reviewed-by: Stefan Hajnoczi <stefanha@redhat.com>
Link: https://patch.msgid.link/20260918140641.2031075-2-cassel@kernel.org
Signed-off-by: Jens Axboe <axboe@kernel.dk>

1 files changed, 208 insertions, 0 deletions

diff --git a/scripts/checkstack.pl b/scripts/checkstack.pl
new file mode 100755
index 000000000..14ce31f73
--- /dev/null
+++ b/scripts/checkstack.pl
@@ -0,0 +1,208 @@
+#!/usr/bin/env perl
+# SPDX-License-Identifier: GPL-2.0
+
+#	Check the stack usage of functions
+#
+#	Copyright Joern Engel <joern@lazybastard.org>
+#	Inspired by Linus Torvalds
+#	Original idea maybe from Keith Owens
+#	s390 port and big speedup by Arnd Bergmann <arnd@bergmann-dalldorf.de>
+#	Mips port by Juan Quintela <quintela@mandrakesoft.com>
+#	Arm port by Holger Schurig
+#	Random bits by Matt Mackall <mpm@selenic.com>
+#	M68k port by Geert Uytterhoeven and Andreas Schwab
+#	AArch64, PARISC ports by Kyle McMartin
+#	sparc port by Martin Habets <errandir_news@mph.eclipse.co.uk>
+#	ppc64le port by Breno Leitao <leitao@debian.org>
+#	riscv port by Wadim Mueller <wafgo01@gmail.com>
+#	loongarch port by Youling Tang <tangyouling@kylinos.cn>
+#
+#	Usage:
+#	objdump -d vmlinux | scripts/checkstack.pl [arch] [min_stack]
+#
+#	TODO :	Port to all architectures (one regex per arch)
+
+use strict;
+
+# check for arch
+#
+# $re is used for two matches:
+# $& (whole re) matches the complete objdump line with the stack growth
+# $1 (first bracket) matches the size of the stack growth
+#
+# $dre is similar, but for dynamic stack redutions:
+# $& (whole re) matches the complete objdump line with the stack growth
+# $1 (first bracket) matches the dynamic amount of the stack growth
+#
+# $sub: subroutine for special handling to check stack usage.
+#
+# use anything else and feel the pain ;)
+my (@stack, $re, $dre, $sub, $x, $xs, $funcre, $min_stack);
+{
+	my $arch = shift;
+	if ($arch eq "") {
+		$arch = `uname -m`;
+		chomp($arch);
+	}
+
+	$min_stack = shift;
+	if ($min_stack eq "" || $min_stack !~ /^\d+$/) {
+		$min_stack = 512;
+	}
+
+	$x	= "[0-9a-f]";	# hex character
+	$xs	= "[0-9a-f ]";	# hex character or space
+	$funcre = qr/^$x* <(.*)>:$/;
+	if ($arch =~ '^(aarch|arm)64$') {
+		#ffffffc0006325cc:       a9bb7bfd        stp     x29, x30, [sp, #-80]!
+		#a110:       d11643ff        sub     sp, sp, #0x590
+		$re = qr/^.*stp.*sp, ?\#-([0-9]{1,8})\]\!/o;
+		$dre = qr/^.*sub.*sp, sp, #(0x$x{1,8})/o;
+	} elsif ($arch eq 'arm') {
+		#c0008ffc:	e24dd064	sub	sp, sp, #100	; 0x64
+		$re = qr/.*sub.*sp, sp, #([0-9]{1,4})/o;
+		$sub = \&arm_push_handling;
+	} elsif ($arch =~ /^x86(_64)?$/ || $arch =~ /^i[3456]86$/) {
+		#c0105234:       81 ec ac 05 00 00       sub    $0x5ac,%esp
+		# or
+		#    2f60:    48 81 ec e8 05 00 00       sub    $0x5e8,%rsp
+		$re = qr/^.*[as][du][db]    \$(0x$x{1,8}),\%(e|r)sp$/o;
+		$dre = qr/^.*[as][du][db]    (%.*),\%(e|r)sp$/o;
+	} elsif ($arch eq 'm68k') {
+		#    2b6c:       4e56 fb70       linkw %fp,#-1168
+		#  1df770:       defc ffe4       addaw #-28,%sp
+		$re = qr/.*(?:linkw %fp,|addaw )#-([0-9]{1,4})(?:,%sp)?$/o;
+	} elsif ($arch eq 'mips64') {
+		#8800402c:       67bdfff0        daddiu  sp,sp,-16
+		$re = qr/.*daddiu.*sp,sp,-([0-9]{1,8})/o;
+	} elsif ($arch eq 'mips') {
+		#88003254:       27bdffe0        addiu   sp,sp,-32
+		$re = qr/.*addiu.*sp,sp,-([0-9]{1,8})/o;
+	} elsif ($arch eq 'nios2') {
+		#25a8:	defffb04 	addi	sp,sp,-20
+		$re = qr/.*addi.*sp,sp,-([0-9]{1,8})/o;
+	} elsif ($arch eq 'openrisc') {
+		# c000043c:       9c 21 fe f0     l.addi r1,r1,-272
+		$re = qr/.*l\.addi.*r1,r1,-([0-9]{1,8})/o;
+	} elsif ($arch eq 'parisc' || $arch eq 'parisc64') {
+		$re = qr/.*ldo ($x{1,8})\(sp\),sp/o;
+	} elsif ($arch eq 'powerpc' || $arch =~ /^ppc(64)?(le)?$/ ) {
+		# powerpc    : 94 21 ff 30     stwu    r1,-208(r1)
+		# ppc64(le)  : 81 ff 21 f8     stdu    r1,-128(r1)
+		$re = qr/.*st[dw]u.*r1,-($x{1,8})\(r1\)/o;
+	} elsif ($arch =~ /^s390x?$/) {
+		#   11160:       a7 fb ff 60             aghi   %r15,-160
+		# or
+		#  100092:	 e3 f0 ff c8 ff 71	 lay	 %r15,-56(%r15)
+		$re = qr/.*(?:lay|ag?hi).*\%r15,-([0-9]+)(?:\(\%r15\))?$/o;
+	} elsif ($arch eq 'sparc' || $arch eq 'sparc64') {
+		# f0019d10:       9d e3 bf 90     save  %sp, -112, %sp
+		$re = qr/.*save.*%sp, -([0-9]{1,8}), %sp/o;
+	} elsif ($arch =~ /^riscv(64)?$/) {
+		#ffffffff8036e868:	c2010113          	addi	sp,sp,-992
+		$re = qr/.*addi.*sp,sp,-([0-9]{1,8})/o;
+	} elsif ($arch =~ /^loongarch(32|64)?$/) {
+		#9000000000224708:	02ff4063		addi.d  $sp, $sp, -48(0xfd0)
+		$re = qr/.*addi\..*sp, .*sp, -([0-9]{1,8}).*/o;
+	} else {
+		print("wrong or unknown architecture \"$arch\"\n");
+		exit
+	}
+}
+
+#
+# To count stack usage of push {*, fp, ip, lr, pc} instruction in ARM,
+# if FRAME POINTER is enabled.
+# e.g. c01f0d48: e92ddff0 push {r4, r5, r6, r7, r8, r9, sl, fp, ip, lr, pc}
+#
+sub arm_push_handling {
+	my $regex = qr/.*push.*fp, ip, lr, pc}/o;
+	my $size = 0;
+	my $line_arg = shift;
+
+	if ($line_arg =~ m/$regex/) {
+		$size = $line_arg =~ tr/,//;
+		$size = ($size + 1) * 4;
+	}
+
+	return $size;
+}
+
+#
+# main()
+#
+my ($func, $file, $lastslash, $total_size, $addr, $intro);
+
+$total_size = 0;
+
+while (my $line = <STDIN>) {
+	if ($line =~ m/$funcre/) {
+		$func = $1;
+		next if $line !~ m/^($x*)/;
+		if ($total_size > $min_stack) {
+			push @stack, "$intro$total_size\n";
+		}
+		$addr = "0x$1";
+		$intro = "$addr $func [$file]:";
+		my $padlen = 56 - length($intro);
+		while ($padlen > 0) {
+			$intro .= '	';
+			$padlen -= 8;
+		}
+
+		$total_size = 0;
+	}
+	elsif ($line =~ m/(.*):\s*file format/) {
+		$file = $1;
+		$file =~ s/\.ko//;
+		$lastslash = rindex($file, "/");
+		if ($lastslash != -1) {
+			$file = substr($file, $lastslash + 1);
+		}
+	}
+	elsif ($line =~ m/$re/) {
+		my $size = $1;
+		$size = hex($size) if ($size =~ /^0x/);
+
+		if ($size > 0xf0000000) {
+			$size = - $size;
+			$size += 0x80000000;
+			$size += 0x80000000;
+		}
+		next if ($size > 0x10000000);
+
+		$total_size += $size;
+	}
+	elsif (defined $dre && $line =~ m/$dre/) {
+		my $size = $1;
+
+		$size = hex($size) if ($size =~ /^0x/);
+		$total_size += $size;
+	}
+	elsif (defined $sub) {
+		my $size = &$sub($line);
+
+		$total_size += $size;
+	}
+}
+if ($total_size > $min_stack) {
+	push @stack, "$intro$total_size\n";
+}
+
+# Sort output by size (last field) and function name if size is the same
+sub sort_lines {
+	my ($a, $b) = @_;
+
+	my $num_a = $1 if $a =~ /:\t*(\d+)$/;
+	my $num_b = $1 if $b =~ /:\t*(\d+)$/;
+	my $func_a = $1 if $a =~ / (.*):/;
+	my $func_b = $1 if $b =~ / (.*):/;
+
+	if ($num_a != $num_b) {
+		return $num_b <=> $num_a;
+	} else {
+		return $func_a cmp $func_b;
+	}
+}
+
+print sort { sort_lines($a, $b) } @stack;