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authorNiklas Cassel <cassel@kernel.org>2026-09-18 16:06:42 +0200
committerJens Axboe <axboe@kernel.dk>2026-09-29 12:54:47 -0600
commit684b413b5483f57c890c171b9400076a0143b918 (patch)
treef167daddad3dce9af44773541373eafbccc9ac61 /drivers/clocksource/timer-pxa.c
downloadlinux-stable-684b413b5483f57c890c171b9400076a0143b918.tar.gz
linux-stable-684b413b5483f57c890c171b9400076a0143b918.zip
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>
Diffstat (limited to 'drivers/clocksource/timer-pxa.c')
-rw-r--r--drivers/clocksource/timer-pxa.c227
1 files changed, 227 insertions, 0 deletions
diff --git a/drivers/clocksource/timer-pxa.c b/drivers/clocksource/timer-pxa.c
new file mode 100644
index 000000000..7ad0e5adb
--- /dev/null
+++ b/drivers/clocksource/timer-pxa.c
@@ -0,0 +1,227 @@
+// SPDX-License-Identifier: GPL-2.0-only
+/*
+ * arch/arm/mach-pxa/time.c
+ *
+ * PXA clocksource, clockevents, and OST interrupt handlers.
+ * Copyright (c) 2007 by Bill Gatliff <bgat@billgatliff.com>.
+ *
+ * Derived from Nicolas Pitre's PXA timer handler Copyright (c) 2001
+ * by MontaVista Software, Inc. (Nico, your code rocks!)
+ */
+
+#include <linux/kernel.h>
+#include <linux/init.h>
+#include <linux/interrupt.h>
+#include <linux/clk.h>
+#include <linux/clockchips.h>
+#include <linux/of_address.h>
+#include <linux/of_irq.h>
+#include <linux/sched/clock.h>
+#include <linux/sched_clock.h>
+
+#include <clocksource/pxa.h>
+
+#include <asm/div64.h>
+
+#define OSMR0 0x00 /* OS Timer 0 Match Register */
+#define OSMR1 0x04 /* OS Timer 1 Match Register */
+#define OSMR2 0x08 /* OS Timer 2 Match Register */
+#define OSMR3 0x0C /* OS Timer 3 Match Register */
+
+#define OSCR 0x10 /* OS Timer Counter Register */
+#define OSSR 0x14 /* OS Timer Status Register */
+#define OWER 0x18 /* OS Timer Watchdog Enable Register */
+#define OIER 0x1C /* OS Timer Interrupt Enable Register */
+
+#define OSSR_M3 (1 << 3) /* Match status channel 3 */
+#define OSSR_M2 (1 << 2) /* Match status channel 2 */
+#define OSSR_M1 (1 << 1) /* Match status channel 1 */
+#define OSSR_M0 (1 << 0) /* Match status channel 0 */
+
+#define OIER_E0 (1 << 0) /* Interrupt enable channel 0 */
+
+/*
+ * This is PXA's sched_clock implementation. This has a resolution
+ * of at least 308 ns and a maximum value of 208 days.
+ *
+ * The return value is guaranteed to be monotonic in that range as
+ * long as there is always less than 582 seconds between successive
+ * calls to sched_clock() which should always be the case in practice.
+ */
+
+#define timer_readl(reg) readl_relaxed(timer_base + (reg))
+#define timer_writel(val, reg) writel_relaxed((val), timer_base + (reg))
+
+static void __iomem *timer_base;
+
+static u64 notrace pxa_read_sched_clock(void)
+{
+ return timer_readl(OSCR);
+}
+
+
+#define MIN_OSCR_DELTA 16
+
+static irqreturn_t
+pxa_ost0_interrupt(int irq, void *dev_id)
+{
+ struct clock_event_device *c = dev_id;
+
+ /* Disarm the compare/match, signal the event. */
+ timer_writel(timer_readl(OIER) & ~OIER_E0, OIER);
+ timer_writel(OSSR_M0, OSSR);
+ c->event_handler(c);
+
+ return IRQ_HANDLED;
+}
+
+static int
+pxa_osmr0_set_next_event(unsigned long delta, struct clock_event_device *dev)
+{
+ unsigned long next, oscr;
+
+ timer_writel(timer_readl(OIER) | OIER_E0, OIER);
+ next = timer_readl(OSCR) + delta;
+ timer_writel(next, OSMR0);
+ oscr = timer_readl(OSCR);
+
+ return (signed)(next - oscr) <= MIN_OSCR_DELTA ? -ETIME : 0;
+}
+
+static int pxa_osmr0_shutdown(struct clock_event_device *evt)
+{
+ /* initializing, released, or preparing for suspend */
+ timer_writel(timer_readl(OIER) & ~OIER_E0, OIER);
+ timer_writel(OSSR_M0, OSSR);
+ return 0;
+}
+
+#ifdef CONFIG_PM
+static unsigned long osmr[4], oier, oscr;
+
+static void pxa_timer_suspend(struct clock_event_device *cedev)
+{
+ osmr[0] = timer_readl(OSMR0);
+ osmr[1] = timer_readl(OSMR1);
+ osmr[2] = timer_readl(OSMR2);
+ osmr[3] = timer_readl(OSMR3);
+ oier = timer_readl(OIER);
+ oscr = timer_readl(OSCR);
+}
+
+static void pxa_timer_resume(struct clock_event_device *cedev)
+{
+ /*
+ * Ensure that we have at least MIN_OSCR_DELTA between match
+ * register 0 and the OSCR, to guarantee that we will receive
+ * the one-shot timer interrupt. We adjust OSMR0 in preference
+ * to OSCR to guarantee that OSCR is monotonically incrementing.
+ */
+ if (osmr[0] - oscr < MIN_OSCR_DELTA)
+ osmr[0] += MIN_OSCR_DELTA;
+
+ timer_writel(osmr[0], OSMR0);
+ timer_writel(osmr[1], OSMR1);
+ timer_writel(osmr[2], OSMR2);
+ timer_writel(osmr[3], OSMR3);
+ timer_writel(oier, OIER);
+ timer_writel(oscr, OSCR);
+}
+#else
+#define pxa_timer_suspend NULL
+#define pxa_timer_resume NULL
+#endif
+
+static struct clock_event_device ckevt_pxa_osmr0 = {
+ .name = "osmr0",
+ .features = CLOCK_EVT_FEAT_ONESHOT,
+ .rating = 200,
+ .set_next_event = pxa_osmr0_set_next_event,
+ .set_state_shutdown = pxa_osmr0_shutdown,
+ .set_state_oneshot = pxa_osmr0_shutdown,
+ .suspend = pxa_timer_suspend,
+ .resume = pxa_timer_resume,
+};
+
+static int __init pxa_timer_common_init(int irq, unsigned long clock_tick_rate)
+{
+ int ret;
+
+ timer_writel(0, OIER);
+ timer_writel(OSSR_M0 | OSSR_M1 | OSSR_M2 | OSSR_M3, OSSR);
+
+ sched_clock_register(pxa_read_sched_clock, 32, clock_tick_rate);
+
+ ckevt_pxa_osmr0.cpumask = cpumask_of(0);
+
+ ret = request_irq(irq, pxa_ost0_interrupt, IRQF_TIMER | IRQF_IRQPOLL,
+ "ost0", &ckevt_pxa_osmr0);
+ if (ret) {
+ pr_err("Failed to setup irq\n");
+ return ret;
+ }
+
+ ret = clocksource_mmio_init(timer_base + OSCR, "oscr0", clock_tick_rate, 200,
+ 32, clocksource_mmio_readl_up);
+ if (ret) {
+ pr_err("Failed to init clocksource\n");
+ return ret;
+ }
+
+ clockevents_config_and_register(&ckevt_pxa_osmr0, clock_tick_rate,
+ MIN_OSCR_DELTA * 2, 0x7fffffff);
+
+ return 0;
+}
+
+static int __init pxa_timer_dt_init(struct device_node *np)
+{
+ struct clk *clk;
+ int irq, ret;
+
+ /* timer registers are shared with watchdog timer */
+ timer_base = of_iomap(np, 0);
+ if (!timer_base) {
+ pr_err("%pOFn: unable to map resource\n", np);
+ return -ENXIO;
+ }
+
+ clk = of_clk_get(np, 0);
+ if (IS_ERR(clk)) {
+ pr_crit("%pOFn: unable to get clk\n", np);
+ return PTR_ERR(clk);
+ }
+
+ ret = clk_prepare_enable(clk);
+ if (ret) {
+ pr_crit("Failed to prepare clock\n");
+ return ret;
+ }
+
+ /* we are only interested in OS-timer0 irq */
+ irq = irq_of_parse_and_map(np, 0);
+ if (irq <= 0) {
+ pr_crit("%pOFn: unable to parse OS-timer0 irq\n", np);
+ return -EINVAL;
+ }
+
+ return pxa_timer_common_init(irq, clk_get_rate(clk));
+}
+TIMER_OF_DECLARE(pxa_timer, "marvell,pxa-timer", pxa_timer_dt_init);
+
+/*
+ * Legacy timer init for non device-tree boards.
+ */
+void __init pxa_timer_nodt_init(int irq, void __iomem *base)
+{
+ struct clk *clk;
+
+ timer_base = base;
+ clk = clk_get(NULL, "OSTIMER0");
+ if (clk && !IS_ERR(clk)) {
+ clk_prepare_enable(clk);
+ pxa_timer_common_init(irq, clk_get_rate(clk));
+ } else {
+ pr_crit("%s: unable to get clk\n", __func__);
+ }
+}