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, 176 insertions, 0 deletions

diff --git a/drivers/clocksource/timer-owl.c b/drivers/clocksource/timer-owl.c
new file mode 100644
index 000000000..ac97420bf
--- /dev/null
+++ b/drivers/clocksource/timer-owl.c
@@ -0,0 +1,176 @@
+// SPDX-License-Identifier: GPL-2.0-or-later
+/*
+ * Actions Semi Owl timer
+ *
+ * Copyright 2012 Actions Semi Inc.
+ * Author: Actions Semi, Inc.
+ *
+ * Copyright (c) 2017 SUSE Linux GmbH
+ * Author: Andreas Färber
+ */
+
+#include <linux/clk.h>
+#include <linux/clockchips.h>
+#include <linux/interrupt.h>
+#include <linux/irq.h>
+#include <linux/irqreturn.h>
+#include <linux/sched_clock.h>
+#include <linux/of.h>
+#include <linux/of_address.h>
+#include <linux/of_irq.h>
+
+#define OWL_Tx_CTL		0x0
+#define OWL_Tx_CMP		0x4
+#define OWL_Tx_VAL		0x8
+
+#define OWL_Tx_CTL_PD		BIT(0)
+#define OWL_Tx_CTL_INTEN	BIT(1)
+#define OWL_Tx_CTL_EN		BIT(2)
+
+static void __iomem *owl_timer_base;
+static void __iomem *owl_clksrc_base;
+static void __iomem *owl_clkevt_base;
+
+static inline void owl_timer_reset(void __iomem *base)
+{
+	writel(0, base + OWL_Tx_CTL);
+	writel(0, base + OWL_Tx_VAL);
+	writel(0, base + OWL_Tx_CMP);
+}
+
+static inline void owl_timer_set_enabled(void __iomem *base, bool enabled)
+{
+	u32 ctl = readl(base + OWL_Tx_CTL);
+
+	/* PD bit is cleared when set */
+	ctl &= ~OWL_Tx_CTL_PD;
+
+	if (enabled)
+		ctl |= OWL_Tx_CTL_EN;
+	else
+		ctl &= ~OWL_Tx_CTL_EN;
+
+	writel(ctl, base + OWL_Tx_CTL);
+}
+
+static u64 notrace owl_timer_sched_read(void)
+{
+	return (u64)readl(owl_clksrc_base + OWL_Tx_VAL);
+}
+
+static int owl_timer_set_state_shutdown(struct clock_event_device *evt)
+{
+	owl_timer_set_enabled(owl_clkevt_base, false);
+
+	return 0;
+}
+
+static int owl_timer_set_state_oneshot(struct clock_event_device *evt)
+{
+	owl_timer_reset(owl_clkevt_base);
+
+	return 0;
+}
+
+static int owl_timer_tick_resume(struct clock_event_device *evt)
+{
+	return 0;
+}
+
+static int owl_timer_set_next_event(unsigned long evt,
+				    struct clock_event_device *ev)
+{
+	void __iomem *base = owl_clkevt_base;
+
+	owl_timer_set_enabled(base, false);
+	writel(OWL_Tx_CTL_INTEN, base + OWL_Tx_CTL);
+	writel(0, base + OWL_Tx_VAL);
+	writel(evt, base + OWL_Tx_CMP);
+	owl_timer_set_enabled(base, true);
+
+	return 0;
+}
+
+static struct clock_event_device owl_clockevent = {
+	.name			= "owl_tick",
+	.rating			= 200,
+	.features		= CLOCK_EVT_FEAT_ONESHOT |
+				  CLOCK_EVT_FEAT_DYNIRQ,
+	.set_state_shutdown	= owl_timer_set_state_shutdown,
+	.set_state_oneshot	= owl_timer_set_state_oneshot,
+	.tick_resume		= owl_timer_tick_resume,
+	.set_next_event		= owl_timer_set_next_event,
+};
+
+static irqreturn_t owl_timer1_interrupt(int irq, void *dev_id)
+{
+	struct clock_event_device *evt = (struct clock_event_device *)dev_id;
+
+	writel(OWL_Tx_CTL_PD, owl_clkevt_base + OWL_Tx_CTL);
+
+	evt->event_handler(evt);
+
+	return IRQ_HANDLED;
+}
+
+static int __init owl_timer_init(struct device_node *node)
+{
+	struct clk *clk;
+	unsigned long rate;
+	int timer1_irq, ret;
+
+	owl_timer_base = of_io_request_and_map(node, 0, "owl-timer");
+	if (IS_ERR(owl_timer_base)) {
+		pr_err("Can't map timer registers\n");
+		return PTR_ERR(owl_timer_base);
+	}
+
+	owl_clksrc_base = owl_timer_base + 0x08;
+	owl_clkevt_base = owl_timer_base + 0x14;
+
+	timer1_irq = of_irq_get_byname(node, "timer1");
+	if (timer1_irq <= 0) {
+		pr_err("Can't parse timer1 IRQ\n");
+		return -EINVAL;
+	}
+
+	clk = of_clk_get(node, 0);
+	if (IS_ERR(clk)) {
+		ret = PTR_ERR(clk);
+		pr_err("Failed to get clock for clocksource (%d)\n", ret);
+		return ret;
+	}
+
+	rate = clk_get_rate(clk);
+
+	owl_timer_reset(owl_clksrc_base);
+	owl_timer_set_enabled(owl_clksrc_base, true);
+
+	sched_clock_register(owl_timer_sched_read, 32, rate);
+	ret = clocksource_mmio_init(owl_clksrc_base + OWL_Tx_VAL, node->name,
+				    rate, 200, 32, clocksource_mmio_readl_up);
+	if (ret) {
+		pr_err("Failed to register clocksource (%d)\n", ret);
+		return ret;
+	}
+
+	owl_timer_reset(owl_clkevt_base);
+
+	ret = request_irq(timer1_irq, owl_timer1_interrupt, IRQF_TIMER,
+			  "owl-timer", &owl_clockevent);
+	if (ret) {
+		pr_err("failed to request irq %d\n", timer1_irq);
+		return ret;
+	}
+
+	owl_clockevent.cpumask = cpumask_of(0);
+	owl_clockevent.irq = timer1_irq;
+
+	clockevents_config_and_register(&owl_clockevent, rate,
+					0xf, 0xffffffff);
+
+	return 0;
+}
+TIMER_OF_DECLARE(owl_s500, "actions,s500-timer", owl_timer_init);
+TIMER_OF_DECLARE(owl_s700, "actions,s700-timer", owl_timer_init);
+TIMER_OF_DECLARE(owl_s900, "actions,s900-timer", owl_timer_init);