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, 207 insertions, 0 deletions

diff --git a/drivers/clocksource/timer-imx-sysctr.c b/drivers/clocksource/timer-imx-sysctr.c
new file mode 100644
index 000000000..dfbd77950
--- /dev/null
+++ b/drivers/clocksource/timer-imx-sysctr.c
@@ -0,0 +1,207 @@
+// SPDX-License-Identifier: GPL-2.0+
+//
+// Copyright 2017-2019 NXP
+
+#include <linux/interrupt.h>
+#include <linux/clockchips.h>
+#include <linux/slab.h>
+
+#include "timer-of.h"
+
+#define CMP_OFFSET	0x10000
+#define RD_OFFSET	0x20000
+
+#define CNTCV_LO	0x8
+#define CNTCV_HI	0xc
+#define CMPCV_LO	(CMP_OFFSET + 0x20)
+#define CMPCV_HI	(CMP_OFFSET + 0x24)
+#define CMPCR		(CMP_OFFSET + 0x2c)
+#define CNTCV_LO_IMX95	(RD_OFFSET + 0x8)
+#define CNTCV_HI_IMX95	(RD_OFFSET + 0xc)
+
+#define SYS_CTR_EN		0x1
+#define SYS_CTR_IRQ_MASK	0x2
+
+#define SYS_CTR_CLK_DIV		0x3
+
+struct sysctr_private {
+	u32 cmpcr;
+	u32 lo_off;
+	u32 hi_off;
+};
+
+static void sysctr_timer_enable(struct clock_event_device *evt, bool enable)
+{
+	struct timer_of *to = to_timer_of(evt);
+	struct sysctr_private *priv = to->private_data;
+	void __iomem *base = timer_of_base(to);
+
+	writel(enable ? priv->cmpcr | SYS_CTR_EN : priv->cmpcr, base + CMPCR);
+}
+
+static void sysctr_irq_acknowledge(struct clock_event_device *evt)
+{
+	/*
+	 * clear the enable bit(EN =0) will clear
+	 * the status bit(ISTAT = 0), then the interrupt
+	 * signal will be negated(acknowledged).
+	 */
+	sysctr_timer_enable(evt, false);
+}
+
+static inline u64 sysctr_read_counter(struct clock_event_device *evt)
+{
+	struct timer_of *to = to_timer_of(evt);
+	struct sysctr_private *priv = to->private_data;
+	void __iomem *base = timer_of_base(to);
+	u32 cnt_hi, tmp_hi, cnt_lo;
+
+	do {
+		cnt_hi = readl_relaxed(base + priv->hi_off);
+		cnt_lo = readl_relaxed(base + priv->lo_off);
+		tmp_hi = readl_relaxed(base + priv->hi_off);
+	} while (tmp_hi != cnt_hi);
+
+	return  ((u64) cnt_hi << 32) | cnt_lo;
+}
+
+static int sysctr_set_next_event(unsigned long delta,
+				 struct clock_event_device *evt)
+{
+	struct timer_of *to = to_timer_of(evt);
+	void __iomem *base = timer_of_base(to);
+	u32 cmp_hi, cmp_lo;
+	u64 next;
+
+	sysctr_timer_enable(evt, false);
+
+	next = sysctr_read_counter(evt);
+
+	next += delta;
+
+	cmp_hi = (next >> 32) & 0x00fffff;
+	cmp_lo = next & 0xffffffff;
+
+	writel_relaxed(cmp_hi, base + CMPCV_HI);
+	writel_relaxed(cmp_lo, base + CMPCV_LO);
+
+	sysctr_timer_enable(evt, true);
+
+	return 0;
+}
+
+static int sysctr_set_state_oneshot(struct clock_event_device *evt)
+{
+	return 0;
+}
+
+static int sysctr_set_state_shutdown(struct clock_event_device *evt)
+{
+	sysctr_timer_enable(evt, false);
+
+	return 0;
+}
+
+static irqreturn_t sysctr_timer_interrupt(int irq, void *dev_id)
+{
+	struct clock_event_device *evt = dev_id;
+
+	sysctr_irq_acknowledge(evt);
+
+	evt->event_handler(evt);
+
+	return IRQ_HANDLED;
+}
+
+static struct timer_of to_sysctr = {
+	.flags = TIMER_OF_IRQ | TIMER_OF_CLOCK | TIMER_OF_BASE,
+	.clkevt = {
+		.name			= "i.MX system counter timer",
+		.features		= CLOCK_EVT_FEAT_ONESHOT |
+						CLOCK_EVT_FEAT_DYNIRQ,
+		.set_state_oneshot	= sysctr_set_state_oneshot,
+		.set_next_event		= sysctr_set_next_event,
+		.set_state_shutdown	= sysctr_set_state_shutdown,
+		.rating			= 200,
+	},
+	.of_irq = {
+		.handler		= sysctr_timer_interrupt,
+		.flags			= IRQF_TIMER,
+	},
+	.of_clk = {
+		.name = "per",
+	},
+};
+
+static int __init __sysctr_timer_init(struct device_node *np)
+{
+	struct sysctr_private *priv;
+	void __iomem *base;
+	int ret;
+
+	priv = kzalloc_obj(struct sysctr_private);
+	if (!priv)
+		return -ENOMEM;
+
+	ret = timer_of_init(np, &to_sysctr);
+	if (ret) {
+		kfree(priv);
+		return ret;
+	}
+
+	if (!of_property_read_bool(np, "nxp,no-divider")) {
+		/* system counter clock is divided by 3 internally */
+		to_sysctr.of_clk.rate /= SYS_CTR_CLK_DIV;
+	}
+
+	to_sysctr.clkevt.cpumask = cpu_possible_mask;
+	to_sysctr.private_data = priv;
+
+	base = timer_of_base(&to_sysctr);
+	priv->cmpcr = readl(base + CMPCR) & ~SYS_CTR_EN;
+
+	return 0;
+}
+
+static int __init sysctr_timer_init(struct device_node *np)
+{
+	struct sysctr_private *priv;
+	int ret;
+
+	ret = __sysctr_timer_init(np);
+	if (ret)
+		return ret;
+
+	priv = to_sysctr.private_data;
+	priv->lo_off = CNTCV_LO;
+	priv->hi_off = CNTCV_HI;
+
+	clockevents_config_and_register(&to_sysctr.clkevt,
+					timer_of_rate(&to_sysctr),
+					0xff, 0x7fffffff);
+
+	return 0;
+}
+
+static int __init sysctr_timer_imx95_init(struct device_node *np)
+{
+	struct sysctr_private *priv;
+	int ret;
+
+	ret = __sysctr_timer_init(np);
+	if (ret)
+		return ret;
+
+	priv = to_sysctr.private_data;
+	priv->lo_off = CNTCV_LO_IMX95;
+	priv->hi_off = CNTCV_HI_IMX95;
+
+	clockevents_config_and_register(&to_sysctr.clkevt,
+					timer_of_rate(&to_sysctr),
+					0xff, 0x7fffffff);
+
+	return 0;
+}
+
+TIMER_OF_DECLARE(sysctr_timer, "nxp,sysctr-timer", sysctr_timer_init);
+TIMER_OF_DECLARE(sysctr_timer_imx95, "nxp,imx95-sysctr-timer", sysctr_timer_imx95_init);