[PATCH v2 0/6] irq/irq_sim: try to improve the API

[PATCH v2 0/6] irq/irq_sim: try to improve the API

[Bartosz Golaszewski]

From: Bartosz Golaszewski <bgolaszewski@baylibre.com>

This is my second take at improving the interrupt simulator interface.
I marked it as v2 but it actually takes a completely different approach.

The interrupt simulator API exposes a lot of custom data structures and
functions and doesn't reuse the interfaces already exposed by the irq
subsystem. This series tries to address it.

First, we make irq_domain_reset_irq_data() available to non-V2 domain API
users - that'll be used in the subsequent patch. Next we overhaul the
public interfaces - we hide all specific data structures and instead
rely on the irq_domain struct and virtual interrupt numberspace.

Next four patches simplify the interface even more, but since the change
may be a bit more controversial due to modification of the irq_domain
I decided to split them out of the second patch.

In patch 3/6 we're adding a new callback to irq_domain_ops that is called
right before all the other code in irq_domain_remove(). Next we use it to
remove the simulator-specific cleanup function from irq_sim.h - users now
can simply use the regular irq_domain_remove().

Last two patches show that the new callback isn't limited to the interrupt
simulator and can be used to shrink code in real driver too. We introduce
a new helper for a common use case of disposing of all mappings before
removing the irq_domain and use it in the keystone irqchip driver.

The end effect is that we limit the interrupt simulator API to two
functions (plus one device managed variant) and zero new structures.

v1: https://lkml.org/lkml/2019/8/12/558

v1 -> v2:
- instead of just making the new data structures opaque for users, remove
  them entirely in favor of irq_domain
- call irq_set_handler() & irq_domain_reset_irq_data() when unmapping
  the simulated interrupt
- fix a memory leak in error path
- make it possible to use irq_find_matching_fwnode() with the simulator
  domain
- correctly use irq_create_mapping() and irq_find_mapping(): only use the
  former at init-time and the latter at interrupt-time

Bartosz Golaszewski (6):
  irq: make irq_domain_reset_irq_data() available even for non-V2 users
  irq/irq_sim: simplify the API
  irq/domain: add a new callback to domain ops
  irq/irq_sim: remove irq_domain_remove_sim()
  irq/domain: provide irq_domain_dispose_mappings() helper
  irqchip: keystone: use irq_domain_dispose_mappings()

 drivers/gpio/gpio-mockup.c          |  47 ++++--
 drivers/iio/dummy/iio_dummy_evgen.c |  32 ++--
 drivers/irqchip/irq-keystone.c      |   5 +-
 include/linux/irq_sim.h             |  33 ++--
 include/linux/irqdomain.h           |   9 +-
 kernel/irq/Kconfig                  |   1 +
 kernel/irq/irq_sim.c                | 225 ++++++++++++++++------------
 kernel/irq/irqdomain.c              |  44 ++++--
 8 files changed, 238 insertions(+), 158 deletions(-)

-- 
2.25.0

[PATCH v2 1/6] irq: make irq_domain_reset_irq_data() available even for non-V2 users

[Bartosz Golaszewski]

From: Bartosz Golaszewski <bgolaszewski@baylibre.com>

irq_domain_reset_irq_data() doesn't modify the parent data, so it can be
made available even if irq domain hierarchy is not being built.

Signed-off-by: Bartosz Golaszewski <bgolaszewski@baylibre.com>
---
 include/linux/irqdomain.h |  4 ++--
 kernel/irq/irqdomain.c    | 24 ++++++++++++------------
 2 files changed, 14 insertions(+), 14 deletions(-)

diff --git a/include/linux/irqdomain.h b/include/linux/irqdomain.h
index b2d47571ab67..20d38621e2f8 100644
--- a/include/linux/irqdomain.h
+++ b/include/linux/irqdomain.h
@@ -450,6 +450,7 @@ extern void irq_domain_set_info(struct irq_domain *domain, unsigned int virq,
 				irq_hw_number_t hwirq, struct irq_chip *chip,
 				void *chip_data, irq_flow_handler_t handler,
 				void *handler_data, const char *handler_name);
+extern void irq_domain_reset_irq_data(struct irq_data *irq_data);
 #ifdef	CONFIG_IRQ_DOMAIN_HIERARCHY
 extern struct irq_domain *irq_domain_create_hierarchy(struct irq_domain *parent,
 			unsigned int flags, unsigned int size,
@@ -475,7 +476,6 @@ extern int __irq_domain_alloc_irqs(struct irq_domain *domain, int irq_base,
 extern void irq_domain_free_irqs(unsigned int virq, unsigned int nr_irqs);
 extern int irq_domain_activate_irq(struct irq_data *irq_data, bool early);
 extern void irq_domain_deactivate_irq(struct irq_data *irq_data);
-
 static inline int irq_domain_alloc_irqs(struct irq_domain *domain,
 			unsigned int nr_irqs, int node, void *arg)
 {
@@ -491,7 +491,7 @@ extern int irq_domain_set_hwirq_and_chip(struct irq_domain *domain,
 					 irq_hw_number_t hwirq,
 					 struct irq_chip *chip,
 					 void *chip_data);
-extern void irq_domain_reset_irq_data(struct irq_data *irq_data);
+
 extern void irq_domain_free_irqs_common(struct irq_domain *domain,
 					unsigned int virq,
 					unsigned int nr_irqs);
diff --git a/kernel/irq/irqdomain.c b/kernel/irq/irqdomain.c
index 7527e5ef6fe5..039427c98af8 100644
--- a/kernel/irq/irqdomain.c
+++ b/kernel/irq/irqdomain.c
@@ -1047,6 +1047,18 @@ int irq_domain_alloc_descs(int virq, unsigned int cnt, irq_hw_number_t hwirq,
 	return virq;
 }
 
+/**
+ * irq_domain_reset_irq_data - Clear hwirq, chip and chip_data in @irq_data
+ * @irq_data:	The pointer to irq_data
+ */
+void irq_domain_reset_irq_data(struct irq_data *irq_data)
+{
+	irq_data->hwirq = 0;
+	irq_data->chip = &no_irq_chip;
+	irq_data->chip_data = NULL;
+}
+EXPORT_SYMBOL_GPL(irq_domain_reset_irq_data);
+
 #ifdef	CONFIG_IRQ_DOMAIN_HIERARCHY
 /**
  * irq_domain_create_hierarchy - Add a irqdomain into the hierarchy
@@ -1247,18 +1259,6 @@ void irq_domain_set_info(struct irq_domain *domain, unsigned int virq,
 }
 EXPORT_SYMBOL(irq_domain_set_info);
 
-/**
- * irq_domain_reset_irq_data - Clear hwirq, chip and chip_data in @irq_data
- * @irq_data:	The pointer to irq_data
- */
-void irq_domain_reset_irq_data(struct irq_data *irq_data)
-{
-	irq_data->hwirq = 0;
-	irq_data->chip = &no_irq_chip;
-	irq_data->chip_data = NULL;
-}
-EXPORT_SYMBOL_GPL(irq_domain_reset_irq_data);
-
 /**
  * irq_domain_free_irqs_common - Clear irq_data and free the parent
  * @domain:	Interrupt domain to match
-- 
2.25.0

[PATCH v2 2/6] irq/irq_sim: simplify the API

[Bartosz Golaszewski]

From: Bartosz Golaszewski <bgolaszewski@baylibre.com>

The interrupt simulator API exposes a lot of custom data structures and
functions and doesn't reuse the interfaces already exposed by the irq
subsystem. This patch tries to address it.

We hide all the simulator-related data structures from users and instead
rely on the well-known irq domain. When creating the interrupt simulator
the user receives a pointer to a newly created irq_domain and can use it
to create mappings for simulated interrupts.

It is also possible to pass a handle to fwnode when creating the simulator
domain and retrieve it using irq_find_matching_fwnode().

The irq_sim_fire() function now only takes the virtual interrupt number
as argument - there's no need anymore to pass it any data structure linked
to the simulator.

We modify the two modules that use the simulator at the same time as
adding these changes in order to reduce the intermediate bloat that would
result when trying to migrate the drivers in separate patches.

Signed-off-by: Bartosz Golaszewski <bgolaszewski@baylibre.com>
---
 drivers/gpio/gpio-mockup.c          |  47 ++++--
 drivers/iio/dummy/iio_dummy_evgen.c |  32 ++--
 include/linux/irq_sim.h             |  34 ++---
 kernel/irq/Kconfig                  |   1 +
 kernel/irq/irq_sim.c                | 225 +++++++++++++++++-----------
 5 files changed, 202 insertions(+), 137 deletions(-)

diff --git a/drivers/gpio/gpio-mockup.c b/drivers/gpio/gpio-mockup.c
index 7d343bea784a..711aa9912271 100644
--- a/drivers/gpio/gpio-mockup.c
+++ b/drivers/gpio/gpio-mockup.c
@@ -14,6 +14,7 @@
 #include <linux/interrupt.h>
 #include <linux/irq.h>
 #include <linux/irq_sim.h>
+#include <linux/irqdomain.h>
 #include <linux/module.h>
 #include <linux/platform_device.h>
 #include <linux/property.h>
@@ -48,7 +49,7 @@ struct gpio_mockup_line_status {
 struct gpio_mockup_chip {
 	struct gpio_chip gc;
 	struct gpio_mockup_line_status *lines;
-	struct irq_sim irqsim;
+	struct irq_domain *irq_sim_domain;
 	struct dentry *dbg_dir;
 	struct mutex lock;
 };
@@ -144,14 +145,12 @@ static void gpio_mockup_set_multiple(struct gpio_chip *gc,
 static int gpio_mockup_apply_pull(struct gpio_mockup_chip *chip,
 				  unsigned int offset, int value)
 {
+	int curr, irq, irq_type, ret = 0;
 	struct gpio_desc *desc;
 	struct gpio_chip *gc;
-	struct irq_sim *sim;
-	int curr, irq, irq_type;
 
 	gc = &chip->gc;
 	desc = &gc->gpiodev->descs[offset];
-	sim = &chip->irqsim;
 
 	mutex_lock(&chip->lock);
 
@@ -161,14 +160,24 @@ static int gpio_mockup_apply_pull(struct gpio_mockup_chip *chip,
 		if (curr == value)
 			goto out;
 
-		irq = irq_sim_irqnum(sim, offset);
+		irq = irq_find_mapping(chip->irq_sim_domain, offset);
+		if (!irq)
+			/*
+			 * This is fine - it just means, nobody is listening
+			 * for interrupts on this line, otherwise
+			 * irq_create_mapping() would have been called from
+			 * the to_irq() callback.
+			 */
+			goto set_value;
+
 		irq_type = irq_get_trigger_type(irq);
 
 		if ((value == 1 && (irq_type & IRQ_TYPE_EDGE_RISING)) ||
 		    (value == 0 && (irq_type & IRQ_TYPE_EDGE_FALLING)))
-			irq_sim_fire(sim, offset);
+			irq_sim_fire(irq);
 	}
 
+set_value:
 	/* Change the value unless we're actively driving the line. */
 	if (!test_bit(FLAG_REQUESTED, &desc->flags) ||
 		!test_bit(FLAG_IS_OUT, &desc->flags))
@@ -177,7 +186,7 @@ static int gpio_mockup_apply_pull(struct gpio_mockup_chip *chip,
 out:
 	chip->lines[offset].pull = value;
 	mutex_unlock(&chip->lock);
-	return 0;
+	return ret;
 }
 
 static int gpio_mockup_set_config(struct gpio_chip *gc,
@@ -236,7 +245,7 @@ static int gpio_mockup_to_irq(struct gpio_chip *gc, unsigned int offset)
 {
 	struct gpio_mockup_chip *chip = gpiochip_get_data(gc);
 
-	return irq_sim_irqnum(&chip->irqsim, offset);
+	return irq_create_mapping(chip->irq_sim_domain, offset);
 }
 
 static void gpio_mockup_free(struct gpio_chip *gc, unsigned int offset)
@@ -389,6 +398,19 @@ static int gpio_mockup_name_lines(struct device *dev,
 	return 0;
 }
 
+static void gpio_mockup_dispose_mappings(void *data)
+{
+	struct gpio_mockup_chip *chip = data;
+	struct gpio_chip *gc = &chip->gc;
+	int i, irq;
+
+	for (i = 0; i < gc->ngpio; i++) {
+		irq = irq_find_mapping(chip->irq_sim_domain, i);
+		if (irq)
+			irq_dispose_mapping(irq);
+	}
+}
+
 static int gpio_mockup_probe(struct platform_device *pdev)
 {
 	struct gpio_mockup_chip *chip;
@@ -456,8 +478,13 @@ static int gpio_mockup_probe(struct platform_device *pdev)
 			return rv;
 	}
 
-	rv = devm_irq_sim_init(dev, &chip->irqsim, gc->ngpio);
-	if (rv < 0)
+	chip->irq_sim_domain = devm_irq_domain_create_sim(dev, NULL,
+							  gc->ngpio);
+	if (IS_ERR(chip->irq_sim_domain))
+		return PTR_ERR(chip->irq_sim_domain);
+
+	rv = devm_add_action_or_reset(dev, gpio_mockup_dispose_mappings, chip);
+	if (rv)
 		return rv;
 
 	rv = devm_gpiochip_add_data(dev, &chip->gc, chip);
diff --git a/drivers/iio/dummy/iio_dummy_evgen.c b/drivers/iio/dummy/iio_dummy_evgen.c
index a6edf30567aa..31c9e012abeb 100644
--- a/drivers/iio/dummy/iio_dummy_evgen.c
+++ b/drivers/iio/dummy/iio_dummy_evgen.c
@@ -37,8 +37,7 @@ struct iio_dummy_eventgen {
 	struct iio_dummy_regs regs[IIO_EVENTGEN_NO];
 	struct mutex lock;
 	bool inuse[IIO_EVENTGEN_NO];
-	struct irq_sim irq_sim;
-	int base;
+	struct irq_domain *irq_sim_domain;
 };
 
 /* We can only ever have one instance of this 'device' */
@@ -46,19 +45,17 @@ static struct iio_dummy_eventgen *iio_evgen;
 
 static int iio_dummy_evgen_create(void)
 {
-	int ret;
-
 	iio_evgen = kzalloc(sizeof(*iio_evgen), GFP_KERNEL);
 	if (!iio_evgen)
 		return -ENOMEM;
 
-	ret = irq_sim_init(&iio_evgen->irq_sim, IIO_EVENTGEN_NO);
-	if (ret < 0) {
+	iio_evgen->irq_sim_domain = irq_domain_create_sim(NULL,
+							  IIO_EVENTGEN_NO);
+	if (IS_ERR(iio_evgen->irq_sim_domain)) {
 		kfree(iio_evgen);
-		return ret;
+		return PTR_ERR(iio_evgen->irq_sim_domain);
 	}
 
-	iio_evgen->base = irq_sim_irqnum(&iio_evgen->irq_sim, 0);
 	mutex_init(&iio_evgen->lock);
 
 	return 0;
@@ -80,7 +77,7 @@ int iio_dummy_evgen_get_irq(void)
 	mutex_lock(&iio_evgen->lock);
 	for (i = 0; i < IIO_EVENTGEN_NO; i++) {
 		if (!iio_evgen->inuse[i]) {
-			ret = irq_sim_irqnum(&iio_evgen->irq_sim, i);
+			ret = irq_create_mapping(iio_evgen->irq_sim_domain, i);
 			iio_evgen->inuse[i] = true;
 			break;
 		}
@@ -101,21 +98,27 @@ EXPORT_SYMBOL_GPL(iio_dummy_evgen_get_irq);
  */
 void iio_dummy_evgen_release_irq(int irq)
 {
+	struct irq_data *irqd = irq_get_irq_data(irq);
+
 	mutex_lock(&iio_evgen->lock);
-	iio_evgen->inuse[irq - iio_evgen->base] = false;
+	iio_evgen->inuse[irqd_to_hwirq(irqd)] = false;
+	irq_dispose_mapping(irq);
 	mutex_unlock(&iio_evgen->lock);
 }
 EXPORT_SYMBOL_GPL(iio_dummy_evgen_release_irq);
 
 struct iio_dummy_regs *iio_dummy_evgen_get_regs(int irq)
 {
-	return &iio_evgen->regs[irq - iio_evgen->base];
+	struct irq_data *irqd = irq_get_irq_data(irq);
+
+	return &iio_evgen->regs[irqd_to_hwirq(irqd)];
+
 }
 EXPORT_SYMBOL_GPL(iio_dummy_evgen_get_regs);
 
 static void iio_dummy_evgen_free(void)
 {
-	irq_sim_fini(&iio_evgen->irq_sim);
+	irq_domain_remove_sim(iio_evgen->irq_sim_domain);
 	kfree(iio_evgen);
 }
 
@@ -131,7 +134,7 @@ static ssize_t iio_evgen_poke(struct device *dev,
 {
 	struct iio_dev_attr *this_attr = to_iio_dev_attr(attr);
 	unsigned long event;
-	int ret;
+	int ret, irq;
 
 	ret = kstrtoul(buf, 10, &event);
 	if (ret)
@@ -140,7 +143,8 @@ static ssize_t iio_evgen_poke(struct device *dev,
 	iio_evgen->regs[this_attr->address].reg_id   = this_attr->address;
 	iio_evgen->regs[this_attr->address].reg_data = event;
 
-	irq_sim_fire(&iio_evgen->irq_sim, this_attr->address);
+	irq = irq_find_mapping(iio_evgen->irq_sim_domain, this_attr->address);
+	irq_sim_fire(irq);
 
 	return len;
 }
diff --git a/include/linux/irq_sim.h b/include/linux/irq_sim.h
index 4500d453a63e..26bf6164dcc7 100644
--- a/include/linux/irq_sim.h
+++ b/include/linux/irq_sim.h
@@ -1,41 +1,27 @@
 /* SPDX-License-Identifier: GPL-2.0+ */
 /*
  * Copyright (C) 2017-2018 Bartosz Golaszewski <brgl@bgdev.pl>
+ * Copyright (C) 2020 Bartosz Golaszewski <bgolaszewski@baylibre.com>
  */
 
 #ifndef _LINUX_IRQ_SIM_H
 #define _LINUX_IRQ_SIM_H
 
-#include <linux/irq_work.h>
 #include <linux/device.h>
+#include <linux/fwnode.h>
+#include <linux/irqdomain.h>
 
 /*
  * Provides a framework for allocating simulated interrupts which can be
  * requested like normal irqs and enqueued from process context.
  */
 
-struct irq_sim_work_ctx {
-	struct irq_work		work;
-	unsigned long		*pending;
-};
-
-struct irq_sim_irq_ctx {
-	int			irqnum;
-	bool			enabled;
-};
-
-struct irq_sim {
-	struct irq_sim_work_ctx	work_ctx;
-	int			irq_base;
-	unsigned int		irq_count;
-	struct irq_sim_irq_ctx	*irqs;
-};
-
-int irq_sim_init(struct irq_sim *sim, unsigned int num_irqs);
-int devm_irq_sim_init(struct device *dev, struct irq_sim *sim,
-		      unsigned int num_irqs);
-void irq_sim_fini(struct irq_sim *sim);
-void irq_sim_fire(struct irq_sim *sim, unsigned int offset);
-int irq_sim_irqnum(struct irq_sim *sim, unsigned int offset);
+struct irq_domain *irq_domain_create_sim(struct fwnode_handle *fwnode,
+					 unsigned int num_irqs);
+struct irq_domain *devm_irq_domain_create_sim(struct device *dev,
+					      struct fwnode_handle *fwnode,
+					      unsigned int num_irqs);
+void irq_domain_remove_sim(struct irq_domain *domain);
+void irq_sim_fire(int virq);
 
 #endif /* _LINUX_IRQ_SIM_H */
diff --git a/kernel/irq/Kconfig b/kernel/irq/Kconfig
index f92d9a687372..d0890f7729d4 100644
--- a/kernel/irq/Kconfig
+++ b/kernel/irq/Kconfig
@@ -68,6 +68,7 @@ config IRQ_DOMAIN
 config IRQ_SIM
 	bool
 	select IRQ_WORK
+	select IRQ_DOMAIN
 
 # Support for hierarchical irq domains
 config IRQ_DOMAIN_HIERARCHY
diff --git a/kernel/irq/irq_sim.c b/kernel/irq/irq_sim.c
index b992f88c5613..575c1e3d32a9 100644
--- a/kernel/irq/irq_sim.c
+++ b/kernel/irq/irq_sim.c
@@ -1,14 +1,30 @@
 // SPDX-License-Identifier: GPL-2.0+
 /*
  * Copyright (C) 2017-2018 Bartosz Golaszewski <brgl@bgdev.pl>
+ * Copyright (C) 2020 Bartosz Golaszewski <bgolaszewski@baylibre.com>
  */
 
-#include <linux/slab.h>
-#include <linux/irq_sim.h>
 #include <linux/irq.h>
+#include <linux/irq_sim.h>
+#include <linux/irq_work.h>
+#include <linux/slab.h>
+
+struct irq_sim_work_ctx {
+	struct irq_work		work;
+	int			irq_base;
+	unsigned int		irq_count;
+	unsigned long		*pending;
+	struct irq_domain	*domain;
+};
+
+struct irq_sim_irq_ctx {
+	int			irqnum;
+	bool			enabled;
+	struct irq_sim_work_ctx	*work_ctx;
+};
 
 struct irq_sim_devres {
-	struct irq_sim		*sim;
+	struct irq_domain	*domain;
 };
 
 static void irq_sim_irqmask(struct irq_data *data)
@@ -47,148 +63,179 @@ static void irq_sim_handle_irq(struct irq_work *work)
 {
 	struct irq_sim_work_ctx *work_ctx;
 	unsigned int offset = 0;
-	struct irq_sim *sim;
 	int irqnum;
 
 	work_ctx = container_of(work, struct irq_sim_work_ctx, work);
-	sim = container_of(work_ctx, struct irq_sim, work_ctx);
 
-	while (!bitmap_empty(work_ctx->pending, sim->irq_count)) {
+	while (!bitmap_empty(work_ctx->pending, work_ctx->irq_count)) {
 		offset = find_next_bit(work_ctx->pending,
-				       sim->irq_count, offset);
+				       work_ctx->irq_count, offset);
 		clear_bit(offset, work_ctx->pending);
-		irqnum = irq_sim_irqnum(sim, offset);
+		irqnum = irq_find_mapping(work_ctx->domain, offset);
 		handle_simple_irq(irq_to_desc(irqnum));
 	}
 }
 
+static int irq_sim_domain_map(struct irq_domain *domain,
+			      unsigned int virq, irq_hw_number_t hw)
+{
+	struct irq_sim_work_ctx *work_ctx = domain->host_data;
+	struct irq_sim_irq_ctx *irq_ctx;
+
+	irq_ctx = kzalloc(sizeof(*irq_ctx), GFP_KERNEL);
+	if (!irq_ctx)
+		return -ENOMEM;
+
+	irq_set_chip(virq, &irq_sim_irqchip);
+	irq_set_chip_data(virq, irq_ctx);
+	irq_set_handler(virq, handle_simple_irq);
+	irq_modify_status(virq, IRQ_NOREQUEST | IRQ_NOAUTOEN, IRQ_NOPROBE);
+	irq_ctx->work_ctx = work_ctx;
+
+	return 0;
+}
+
+static void irq_sim_domain_unmap(struct irq_domain *domain, unsigned int virq)
+{
+	struct irq_sim_irq_ctx *irq_ctx;
+	struct irq_data *irqd;
+
+	irqd = irq_domain_get_irq_data(domain, virq);
+	irq_ctx = irq_data_get_irq_chip_data(irqd);
+
+	irq_set_handler(virq, NULL);
+	irq_domain_reset_irq_data(irqd);
+	kfree(irq_ctx);
+}
+
+static const struct irq_domain_ops irq_sim_domain_ops = {
+	.map		= irq_sim_domain_map,
+	.unmap		= irq_sim_domain_unmap,
+};
+
 /**
- * irq_sim_init - Initialize the interrupt simulator: allocate a range of
- *                dummy interrupts.
+ * irq_domain_create_sim - Create a new interrupt simulator irq_domain and
+ *                         allocate a range of dummy interrupts.
  *
- * @sim:        The interrupt simulator object to initialize.
- * @num_irqs:   Number of interrupts to allocate
+ * @fnode:      struct fwnode_handle to be associated with this domain.
+ * @num_irqs:   Number of interrupts to allocate.
  *
- * On success: return the base of the allocated interrupt range.
- * On failure: a negative errno.
+ * On success: return a new irq_domain object.
+ * On failure: a negative errno wrapped with ERR_PTR().
  */
-int irq_sim_init(struct irq_sim *sim, unsigned int num_irqs)
+struct irq_domain *irq_domain_create_sim(struct fwnode_handle *fwnode,
+					 unsigned int num_irqs)
 {
-	int i;
+	struct irq_sim_work_ctx *work_ctx;
 
-	sim->irqs = kmalloc_array(num_irqs, sizeof(*sim->irqs), GFP_KERNEL);
-	if (!sim->irqs)
-		return -ENOMEM;
+	work_ctx = kmalloc(sizeof(*work_ctx), GFP_KERNEL);
+	if (!work_ctx)
+		goto err_out;
 
-	sim->irq_base = irq_alloc_descs(-1, 0, num_irqs, 0);
-	if (sim->irq_base < 0) {
-		kfree(sim->irqs);
-		return sim->irq_base;
-	}
+	work_ctx->pending = bitmap_zalloc(num_irqs, GFP_KERNEL);
+	if (!work_ctx->pending)
+		goto err_free_work_ctx;
 
-	sim->work_ctx.pending = bitmap_zalloc(num_irqs, GFP_KERNEL);
-	if (!sim->work_ctx.pending) {
-		kfree(sim->irqs);
-		irq_free_descs(sim->irq_base, num_irqs);
-		return -ENOMEM;
-	}
+	work_ctx->domain = irq_domain_create_linear(fwnode, num_irqs,
+						    &irq_sim_domain_ops,
+						    work_ctx);
+	if (!work_ctx->domain)
+		goto err_free_bitmap;
 
-	for (i = 0; i < num_irqs; i++) {
-		sim->irqs[i].irqnum = sim->irq_base + i;
-		sim->irqs[i].enabled = false;
-		irq_set_chip(sim->irq_base + i, &irq_sim_irqchip);
-		irq_set_chip_data(sim->irq_base + i, &sim->irqs[i]);
-		irq_set_handler(sim->irq_base + i, &handle_simple_irq);
-		irq_modify_status(sim->irq_base + i,
-				  IRQ_NOREQUEST | IRQ_NOAUTOEN, IRQ_NOPROBE);
-	}
+	work_ctx->irq_count = num_irqs;
+	init_irq_work(&work_ctx->work, irq_sim_handle_irq);
 
-	init_irq_work(&sim->work_ctx.work, irq_sim_handle_irq);
-	sim->irq_count = num_irqs;
+	return work_ctx->domain;
 
-	return sim->irq_base;
+err_free_bitmap:
+	bitmap_free(work_ctx->pending);
+err_free_work_ctx:
+	kfree(work_ctx);
+err_out:
+	return ERR_PTR(-ENOMEM);
 }
-EXPORT_SYMBOL_GPL(irq_sim_init);
+EXPORT_SYMBOL_GPL(irq_domain_create_sim);
 
 /**
- * irq_sim_fini - Deinitialize the interrupt simulator: free the interrupt
- *                descriptors and allocated memory.
+ * irq_domain_remove_sim - Deinitialize the interrupt simulator domain: free
+ *                         the interrupt descriptors and allocated memory.
  *
- * @sim:        The interrupt simulator to tear down.
+ * @domain:     The interrupt simulator domain to tear down.
  */
-void irq_sim_fini(struct irq_sim *sim)
+void irq_domain_remove_sim(struct irq_domain *domain)
 {
-	irq_work_sync(&sim->work_ctx.work);
-	bitmap_free(sim->work_ctx.pending);
-	irq_free_descs(sim->irq_base, sim->irq_count);
-	kfree(sim->irqs);
+	struct irq_sim_work_ctx *work_ctx = domain->host_data;
+
+	irq_work_sync(&work_ctx->work);
+	bitmap_free(work_ctx->pending);
+	kfree(work_ctx);
+
+	irq_domain_remove(domain);
 }
-EXPORT_SYMBOL_GPL(irq_sim_fini);
+EXPORT_SYMBOL_GPL(irq_domain_remove_sim);
 
-static void devm_irq_sim_release(struct device *dev, void *res)
+static void devm_irq_domain_release_sim(struct device *dev, void *res)
 {
 	struct irq_sim_devres *this = res;
 
-	irq_sim_fini(this->sim);
+	irq_domain_remove_sim(this->domain);
 }
 
 /**
- * irq_sim_init - Initialize the interrupt simulator for a managed device.
+ * devm_irq_domain_create_sim - Create a new interrupt simulator for
+ *                              a managed device.
  *
  * @dev:        Device to initialize the simulator object for.
- * @sim:        The interrupt simulator object to initialize.
+ * @fnode:      struct fwnode_handle to be associated with this domain.
  * @num_irqs:   Number of interrupts to allocate
  *
- * On success: return the base of the allocated interrupt range.
- * On failure: a negative errno.
+ * On success: return a new irq_domain object.
+ * On failure: a negative errno wrapped with ERR_PTR().
  */
-int devm_irq_sim_init(struct device *dev, struct irq_sim *sim,
-		      unsigned int num_irqs)
+struct irq_domain *devm_irq_domain_create_sim(struct device *dev,
+					      struct fwnode_handle *fwnode,
+					      unsigned int num_irqs)
 {
 	struct irq_sim_devres *dr;
-	int rv;
 
-	dr = devres_alloc(devm_irq_sim_release, sizeof(*dr), GFP_KERNEL);
+	dr = devres_alloc(devm_irq_domain_release_sim,
+			  sizeof(*dr), GFP_KERNEL);
 	if (!dr)
-		return -ENOMEM;
+		return ERR_PTR(-ENOMEM);
 
-	rv = irq_sim_init(sim, num_irqs);
-	if (rv < 0) {
+	dr->domain = irq_domain_create_sim(fwnode, num_irqs);
+	if (IS_ERR(dr->domain)) {
 		devres_free(dr);
-		return rv;
+		return dr->domain;
 	}
 
-	dr->sim = sim;
 	devres_add(dev, dr);
-
-	return rv;
+	return dr->domain;
 }
-EXPORT_SYMBOL_GPL(devm_irq_sim_init);
+EXPORT_SYMBOL_GPL(devm_irq_domain_create_sim);
 
 /**
  * irq_sim_fire - Enqueue an interrupt.
  *
- * @sim:        The interrupt simulator object.
- * @offset:     Offset of the simulated interrupt which should be fired.
+ * @virq:       Virtual interrupt number to fire. It must be associated with
+ *              an existing interrupt simulator.
  */
-void irq_sim_fire(struct irq_sim *sim, unsigned int offset)
+void irq_sim_fire(int virq)
 {
-	if (sim->irqs[offset].enabled) {
-		set_bit(offset, sim->work_ctx.pending);
-		irq_work_queue(&sim->work_ctx.work);
+	struct irq_sim_irq_ctx *irq_ctx;
+	struct irq_data *irqd;
+
+	irqd = irq_get_irq_data(virq);
+	if (!irqd) {
+		pr_warn_ratelimited("%s: invalid irq number\n", __func__);
+		return;
 	}
-}
-EXPORT_SYMBOL_GPL(irq_sim_fire);
 
-/**
- * irq_sim_irqnum - Get the allocated number of a dummy interrupt.
- *
- * @sim:        The interrupt simulator object.
- * @offset:     Offset of the simulated interrupt for which to retrieve
- *              the number.
- */
-int irq_sim_irqnum(struct irq_sim *sim, unsigned int offset)
-{
-	return sim->irqs[offset].irqnum;
+	irq_ctx = irq_data_get_irq_chip_data(irqd);
+
+	if (irq_ctx->enabled) {
+		set_bit(irqd_to_hwirq(irqd), irq_ctx->work_ctx->pending);
+		irq_work_queue(&irq_ctx->work_ctx->work);
+	}
 }
-EXPORT_SYMBOL_GPL(irq_sim_irqnum);
+EXPORT_SYMBOL_GPL(irq_sim_fire);
-- 
2.25.0

[PATCH v2 3/6] irq/domain: add a new callback to domain ops

[Bartosz Golaszewski]

From: Bartosz Golaszewski <bgolaszewski@baylibre.com>

Add the remove() callback to irq_domain_ops which can be used to
automatically dispose of any host data associated with the domain when
irq_domain_remove() is called.

Signed-off-by: Bartosz Golaszewski <bgolaszewski@baylibre.com>
---
 include/linux/irqdomain.h | 3 +++
 kernel/irq/irqdomain.c    | 3 +++
 2 files changed, 6 insertions(+)

diff --git a/include/linux/irqdomain.h b/include/linux/irqdomain.h
index 20d38621e2f8..fbc25f464f62 100644
--- a/include/linux/irqdomain.h
+++ b/include/linux/irqdomain.h
@@ -95,6 +95,8 @@ enum irq_domain_bus_token {
  * @unmap: Dispose of such a mapping
  * @xlate: Given a device tree node and interrupt specifier, decode
  *         the hardware irq number and linux irq type value.
+ * @remove: Free any custom resources associated with this domain. This is
+ *          called from irq_domain_remove() before any other code.
  *
  * Functions below are provided by the driver and called whenever a new mapping
  * is created or an old mapping is disposed. The driver can then proceed to
@@ -126,6 +128,7 @@ struct irq_domain_ops {
 	void (*debug_show)(struct seq_file *m, struct irq_domain *d,
 			   struct irq_data *irqd, int ind);
 #endif
+	void (*remove)(struct irq_domain *d);
 };
 
 extern struct irq_domain_ops irq_generic_chip_ops;
diff --git a/kernel/irq/irqdomain.c b/kernel/irq/irqdomain.c
index 039427c98af8..b391d2e65bdd 100644
--- a/kernel/irq/irqdomain.c
+++ b/kernel/irq/irqdomain.c
@@ -242,6 +242,9 @@ EXPORT_SYMBOL_GPL(__irq_domain_add);
  */
 void irq_domain_remove(struct irq_domain *domain)
 {
+	if (domain->ops->remove)
+		domain->ops->remove(domain);
+
 	mutex_lock(&irq_domain_mutex);
 	debugfs_remove_domain_dir(domain);
 
-- 
2.25.0

[PATCH v2 4/6] irq/irq_sim: remove irq_domain_remove_sim()

[Bartosz Golaszewski]

From: Bartosz Golaszewski <bgolaszewski@baylibre.com>

Use the new remove() callback in irq_domain_ops to dispose of any
private data associated with the sim domain. This allows us to drop
the dedicated irq_domain_remove_sim() function and instead just use
the regular irq_domain_remove().

Signed-off-by: Bartosz Golaszewski <bgolaszewski@baylibre.com>
---
 drivers/iio/dummy/iio_dummy_evgen.c |  2 +-
 include/linux/irq_sim.h             |  1 -
 kernel/irq/irq_sim.c                | 32 ++++++++++++-----------------
 3 files changed, 14 insertions(+), 21 deletions(-)

diff --git a/drivers/iio/dummy/iio_dummy_evgen.c b/drivers/iio/dummy/iio_dummy_evgen.c
index 31c9e012abeb..47620bdae845 100644
--- a/drivers/iio/dummy/iio_dummy_evgen.c
+++ b/drivers/iio/dummy/iio_dummy_evgen.c
@@ -118,7 +118,7 @@ EXPORT_SYMBOL_GPL(iio_dummy_evgen_get_regs);
 
 static void iio_dummy_evgen_free(void)
 {
-	irq_domain_remove_sim(iio_evgen->irq_sim_domain);
+	irq_domain_remove(iio_evgen->irq_sim_domain);
 	kfree(iio_evgen);
 }
 
diff --git a/include/linux/irq_sim.h b/include/linux/irq_sim.h
index 26bf6164dcc7..90e910fa2f91 100644
--- a/include/linux/irq_sim.h
+++ b/include/linux/irq_sim.h
@@ -21,7 +21,6 @@ struct irq_domain *irq_domain_create_sim(struct fwnode_handle *fwnode,
 struct irq_domain *devm_irq_domain_create_sim(struct device *dev,
 					      struct fwnode_handle *fwnode,
 					      unsigned int num_irqs);
-void irq_domain_remove_sim(struct irq_domain *domain);
 void irq_sim_fire(int virq);
 
 #endif /* _LINUX_IRQ_SIM_H */
diff --git a/kernel/irq/irq_sim.c b/kernel/irq/irq_sim.c
index 575c1e3d32a9..a4400aed5fb2 100644
--- a/kernel/irq/irq_sim.c
+++ b/kernel/irq/irq_sim.c
@@ -108,9 +108,19 @@ static void irq_sim_domain_unmap(struct irq_domain *domain, unsigned int virq)
 	kfree(irq_ctx);
 }
 
+static void irq_sim_domain_remove(struct irq_domain *domain)
+{
+	struct irq_sim_work_ctx *work_ctx = domain->host_data;
+
+	irq_work_sync(&work_ctx->work);
+	bitmap_free(work_ctx->pending);
+	kfree(work_ctx);
+}
+
 static const struct irq_domain_ops irq_sim_domain_ops = {
 	.map		= irq_sim_domain_map,
 	.unmap		= irq_sim_domain_unmap,
+	.remove		= irq_sim_domain_remove,
 };
 
 /**
@@ -122,6 +132,8 @@ static const struct irq_domain_ops irq_sim_domain_ops = {
  *
  * On success: return a new irq_domain object.
  * On failure: a negative errno wrapped with ERR_PTR().
+ *
+ * The returned domain can be freed using irq_domain_remove().
  */
 struct irq_domain *irq_domain_create_sim(struct fwnode_handle *fwnode,
 					 unsigned int num_irqs)
@@ -156,29 +168,11 @@ struct irq_domain *irq_domain_create_sim(struct fwnode_handle *fwnode,
 }
 EXPORT_SYMBOL_GPL(irq_domain_create_sim);
 
-/**
- * irq_domain_remove_sim - Deinitialize the interrupt simulator domain: free
- *                         the interrupt descriptors and allocated memory.
- *
- * @domain:     The interrupt simulator domain to tear down.
- */
-void irq_domain_remove_sim(struct irq_domain *domain)
-{
-	struct irq_sim_work_ctx *work_ctx = domain->host_data;
-
-	irq_work_sync(&work_ctx->work);
-	bitmap_free(work_ctx->pending);
-	kfree(work_ctx);
-
-	irq_domain_remove(domain);
-}
-EXPORT_SYMBOL_GPL(irq_domain_remove_sim);
-
 static void devm_irq_domain_release_sim(struct device *dev, void *res)
 {
 	struct irq_sim_devres *this = res;
 
-	irq_domain_remove_sim(this->domain);
+	irq_domain_remove(this->domain);
 }
 
 /**
-- 
2.25.0

[PATCH v2 5/6] irq/domain: provide irq_domain_dispose_mappings() helper

[Bartosz Golaszewski]

From: Bartosz Golaszewski <bgolaszewski@baylibre.com>

Unmapping all interrupts before removing an irq_domain is a common
use-case. Provide an appropriate helper that can also be used with
the remove() callback in irq_domain ops.

Signed-off-by: Bartosz Golaszewski <bgolaszewski@baylibre.com>
---
 include/linux/irqdomain.h |  2 ++
 kernel/irq/irqdomain.c    | 17 +++++++++++++++++
 2 files changed, 19 insertions(+)

diff --git a/include/linux/irqdomain.h b/include/linux/irqdomain.h
index fbc25f464f62..8fd27614dafd 100644
--- a/include/linux/irqdomain.h
+++ b/include/linux/irqdomain.h
@@ -390,6 +390,7 @@ extern unsigned int irq_create_mapping(struct irq_domain *host,
 				       irq_hw_number_t hwirq);
 extern unsigned int irq_create_fwspec_mapping(struct irq_fwspec *fwspec);
 extern void irq_dispose_mapping(unsigned int virq);
+extern void irq_domain_dispose_mappings(struct irq_domain *domain);
 
 /**
  * irq_linear_revmap() - Find a linux irq from a hw irq number.
@@ -594,6 +595,7 @@ irq_domain_hierarchical_is_msi_remap(struct irq_domain *domain)
 
 #else /* CONFIG_IRQ_DOMAIN */
 static inline void irq_dispose_mapping(unsigned int virq) { }
+static inline void irq_domain_dispose_mappings(struct irq_domain *domain) { }
 static inline struct irq_domain *irq_find_matching_fwnode(
 	struct fwnode_handle *fwnode, enum irq_domain_bus_token bus_token)
 {
diff --git a/kernel/irq/irqdomain.c b/kernel/irq/irqdomain.c
index b391d2e65bdd..d09de9f2411a 100644
--- a/kernel/irq/irqdomain.c
+++ b/kernel/irq/irqdomain.c
@@ -888,6 +888,23 @@ void irq_dispose_mapping(unsigned int virq)
 }
 EXPORT_SYMBOL_GPL(irq_dispose_mapping);
 
+/**
+ * irq_domain_dispose_mappings() - Unmap all interrupts
+ * @domain: domain for which to unmap all interrupts
+ */
+void irq_domain_dispose_mappings(struct irq_domain *domain)
+{
+	unsigned int virq;
+	int i;
+
+	for (i = 0; i < domain->hwirq_max; i++) {
+		virq = irq_find_mapping(domain, i);
+		if (virq)
+			irq_dispose_mapping(virq);
+	}
+}
+EXPORT_SYMBOL_GPL(irq_domain_dispose_mappings);
+
 /**
  * irq_find_mapping() - Find a linux irq from a hw irq number.
  * @domain: domain owning this hardware interrupt
-- 
2.25.0

[PATCH v2 6/6] irqchip: keystone: use irq_domain_dispose_mappings()

[Bartosz Golaszewski]

From: Bartosz Golaszewski <bgolaszewski@baylibre.com>

Shrink the code a bit by using the new irq_domain_dispose_mappings()
helper.

Signed-off-by: Bartosz Golaszewski <bgolaszewski@baylibre.com>
---
 drivers/irqchip/irq-keystone.c | 5 +----
 1 file changed, 1 insertion(+), 4 deletions(-)

diff --git a/drivers/irqchip/irq-keystone.c b/drivers/irqchip/irq-keystone.c
index 8118ebe80b09..57819d1c3c32 100644
--- a/drivers/irqchip/irq-keystone.c
+++ b/drivers/irqchip/irq-keystone.c
@@ -135,6 +135,7 @@ static int keystone_irq_map(struct irq_domain *h, unsigned int virq,
 static const struct irq_domain_ops keystone_irq_ops = {
 	.map	= keystone_irq_map,
 	.xlate	= irq_domain_xlate_onecell,
+	.remove	= irq_domain_dispose_mappings,
 };
 
 static int keystone_irq_probe(struct platform_device *pdev)
@@ -203,13 +204,9 @@ static int keystone_irq_probe(struct platform_device *pdev)
 static int keystone_irq_remove(struct platform_device *pdev)
 {
 	struct keystone_irq_device *kirq = platform_get_drvdata(pdev);
-	int hwirq;
 
 	free_irq(kirq->irq, kirq);
 
-	for (hwirq = 0; hwirq < KEYSTONE_N_IRQ; hwirq++)
-		irq_dispose_mapping(irq_find_mapping(kirq->irqd, hwirq));
-
 	irq_domain_remove(kirq->irqd);
 	return 0;
 }
-- 
2.25.0

Re: [PATCH v2 1/6] irq: make irq_domain_reset_irq_data() available even for non-V2 users

[Thomas Gleixner]

Bartosz Golaszewski <brgl@bgdev.pl> writes:
> From: Bartosz Golaszewski <bgolaszewski@baylibre.com>
>
> irq_domain_reset_irq_data() doesn't modify the parent data, so it can be
> made available even if irq domain hierarchy is not being built.

Yes, it can be made available, but WHY?

Thanks,

        tglx

Re: [PATCH v2 1/6] irq: make irq_domain_reset_irq_data() available even for non-V2 users

[Bartosz Golaszewski]

pt., 14 lut 2020 o 10:02 Thomas Gleixner <tglx@linutronix.de> napisał(a):
>
> Bartosz Golaszewski <brgl@bgdev.pl> writes:
> > From: Bartosz Golaszewski <bgolaszewski@baylibre.com>
> >
> > irq_domain_reset_irq_data() doesn't modify the parent data, so it can be
> > made available even if irq domain hierarchy is not being built.
>
> Yes, it can be made available, but WHY?
>
> Thanks,
>
>         tglx

Duh, I forgot to clarify this. After my previous submission, Marc
suggested I use irq_domain_reset_irq_data() in the unmap() callback
for the simulator domain. I noticed I can't do this because I don't
select the V2 irq domain API, so I added this patch.

Bartosz

Re: [PATCH v2 0/6] irq/irq_sim: try to improve the API

[Bartosz Golaszewski]

wt., 11 lut 2020 o 14:12 Bartosz Golaszewski <brgl@bgdev.pl> napisał(a):
>
> From: Bartosz Golaszewski <bgolaszewski@baylibre.com>
>
> This is my second take at improving the interrupt simulator interface.
> I marked it as v2 but it actually takes a completely different approach.
>
> The interrupt simulator API exposes a lot of custom data structures and
> functions and doesn't reuse the interfaces already exposed by the irq
> subsystem. This series tries to address it.
>
> First, we make irq_domain_reset_irq_data() available to non-V2 domain API
> users - that'll be used in the subsequent patch. Next we overhaul the
> public interfaces - we hide all specific data structures and instead
> rely on the irq_domain struct and virtual interrupt numberspace.
>
> Next four patches simplify the interface even more, but since the change
> may be a bit more controversial due to modification of the irq_domain
> I decided to split them out of the second patch.
>
> In patch 3/6 we're adding a new callback to irq_domain_ops that is called
> right before all the other code in irq_domain_remove(). Next we use it to
> remove the simulator-specific cleanup function from irq_sim.h - users now
> can simply use the regular irq_domain_remove().
>
> Last two patches show that the new callback isn't limited to the interrupt
> simulator and can be used to shrink code in real driver too. We introduce
> a new helper for a common use case of disposing of all mappings before
> removing the irq_domain and use it in the keystone irqchip driver.
>
> The end effect is that we limit the interrupt simulator API to two
> functions (plus one device managed variant) and zero new structures.
>
> v1: https://lkml.org/lkml/2019/8/12/558
>
> v1 -> v2:
> - instead of just making the new data structures opaque for users, remove
>   them entirely in favor of irq_domain
> - call irq_set_handler() & irq_domain_reset_irq_data() when unmapping
>   the simulated interrupt
> - fix a memory leak in error path
> - make it possible to use irq_find_matching_fwnode() with the simulator
>   domain
> - correctly use irq_create_mapping() and irq_find_mapping(): only use the
>   former at init-time and the latter at interrupt-time
>

Hi,

it's been three weeks, so gentle ping on that.

Or should I resend the entire series with a more elaborate commit
message for patch 1/6?

Bartosz

Re: [PATCH v2 3/6] irq/domain: add a new callback to domain ops

[Marc Zyngier]

On Tue, 11 Feb 2020 14:12:37 +0100
Bartosz Golaszewski <brgl@bgdev.pl> wrote:

> From: Bartosz Golaszewski <bgolaszewski@baylibre.com>
> 
> Add the remove() callback to irq_domain_ops which can be used to
> automatically dispose of any host data associated with the domain when
> irq_domain_remove() is called.

I have a hard time buying this. Whatever data that is associated to the
domain is already owned known by whoever created the domain the first
place.

Since the expected use case is that whoever created the domain also
destroys it, the caller is already in a position to do its own cleanup,
and we don't need any of this.

So please explain what you are trying to achieve here.

Thanks,

	M.
-- 
Jazz is not dead. It just smells funny...

Re: [PATCH v2 3/6] irq/domain: add a new callback to domain ops

[Bartosz Golaszewski]

niedz., 8 mar 2020 o 14:51 Marc Zyngier <maz@kernel.org> napisał(a):
>
> On Tue, 11 Feb 2020 14:12:37 +0100
> Bartosz Golaszewski <brgl@bgdev.pl> wrote:
>
> > From: Bartosz Golaszewski <bgolaszewski@baylibre.com>
> >
> > Add the remove() callback to irq_domain_ops which can be used to
> > automatically dispose of any host data associated with the domain when
> > irq_domain_remove() is called.
>
> I have a hard time buying this. Whatever data that is associated to the
> domain is already owned known by whoever created the domain the first
> place.
>
> Since the expected use case is that whoever created the domain also
> destroys it, the caller is already in a position to do its own cleanup,
> and we don't need any of this.
>
> So please explain what you are trying to achieve here.
>

I'm mainly trying to remove irq_domain_remove_sim() and make it
possible to destroy the interrupt simulator domain with regular
irq_domain_remove(). If you prefer that we retain this routine as is,
I can limit this series to the first two patches, but I assumed the
fewer functions in the interface, the better. If you have a different
idea on how to do this - please let me know too.

Bartosz

Re: [PATCH v2 3/6] irq/domain: add a new callback to domain ops

[Bartosz Golaszewski]

niedz., 8 mar 2020 o 18:59 Bartosz Golaszewski <brgl@bgdev.pl> napisał(a):
>
> niedz., 8 mar 2020 o 14:51 Marc Zyngier <maz@kernel.org> napisał(a):
> >
> > On Tue, 11 Feb 2020 14:12:37 +0100
> > Bartosz Golaszewski <brgl@bgdev.pl> wrote:
> >
> > > From: Bartosz Golaszewski <bgolaszewski@baylibre.com>
> > >
> > > Add the remove() callback to irq_domain_ops which can be used to
> > > automatically dispose of any host data associated with the domain when
> > > irq_domain_remove() is called.
> >
> > I have a hard time buying this. Whatever data that is associated to the
> > domain is already owned known by whoever created the domain the first
> > place.
> >
> > Since the expected use case is that whoever created the domain also
> > destroys it, the caller is already in a position to do its own cleanup,
> > and we don't need any of this.
> >
> > So please explain what you are trying to achieve here.
> >
>
> I'm mainly trying to remove irq_domain_remove_sim() and make it
> possible to destroy the interrupt simulator domain with regular
> irq_domain_remove(). If you prefer that we retain this routine as is,
> I can limit this series to the first two patches, but I assumed the
> fewer functions in the interface, the better. If you have a different
> idea on how to do this - please let me know too.
>
> Bartosz

While this is being discussed - are the first two patches
uncontroversial enough to make it into v5.7?

Bartosz

Re: [PATCH v2 3/6] irq/domain: add a new callback to domain ops

[Bartosz Golaszewski]

czw., 12 mar 2020 o 09:15 Bartosz Golaszewski <brgl@bgdev.pl> napisał(a):
>
> niedz., 8 mar 2020 o 18:59 Bartosz Golaszewski <brgl@bgdev.pl> napisał(a):
> >
> > niedz., 8 mar 2020 o 14:51 Marc Zyngier <maz@kernel.org> napisał(a):
> > >
> > > On Tue, 11 Feb 2020 14:12:37 +0100
> > > Bartosz Golaszewski <brgl@bgdev.pl> wrote:
> > >
> > > > From: Bartosz Golaszewski <bgolaszewski@baylibre.com>
> > > >
> > > > Add the remove() callback to irq_domain_ops which can be used to
> > > > automatically dispose of any host data associated with the domain when
> > > > irq_domain_remove() is called.
> > >
> > > I have a hard time buying this. Whatever data that is associated to the
> > > domain is already owned known by whoever created the domain the first
> > > place.
> > >
> > > Since the expected use case is that whoever created the domain also
> > > destroys it, the caller is already in a position to do its own cleanup,
> > > and we don't need any of this.
> > >
> > > So please explain what you are trying to achieve here.
> > >
> >
> > I'm mainly trying to remove irq_domain_remove_sim() and make it
> > possible to destroy the interrupt simulator domain with regular
> > irq_domain_remove(). If you prefer that we retain this routine as is,
> > I can limit this series to the first two patches, but I assumed the
> > fewer functions in the interface, the better. If you have a different
> > idea on how to do this - please let me know too.
> >
> > Bartosz
>
> While this is being discussed - are the first two patches
> uncontroversial enough to make it into v5.7?
>
> Bartosz

Gentle ping after another week.

Bart

Re: [PATCH v2 0/6] irq/irq_sim: try to improve the API

[Jonathan Cameron]

On Tue, 3 Mar 2020 08:57:43 +0100
Bartosz Golaszewski <brgl@bgdev.pl> wrote:

> wt., 11 lut 2020 o 14:12 Bartosz Golaszewski <brgl@bgdev.pl> napisał(a):
> >
> > From: Bartosz Golaszewski <bgolaszewski@baylibre.com>
> >
> > This is my second take at improving the interrupt simulator interface.
> > I marked it as v2 but it actually takes a completely different approach.
> >
> > The interrupt simulator API exposes a lot of custom data structures and
> > functions and doesn't reuse the interfaces already exposed by the irq
> > subsystem. This series tries to address it.
> >
> > First, we make irq_domain_reset_irq_data() available to non-V2 domain API
> > users - that'll be used in the subsequent patch. Next we overhaul the
> > public interfaces - we hide all specific data structures and instead
> > rely on the irq_domain struct and virtual interrupt numberspace.
> >
> > Next four patches simplify the interface even more, but since the change
> > may be a bit more controversial due to modification of the irq_domain
> > I decided to split them out of the second patch.
> >
> > In patch 3/6 we're adding a new callback to irq_domain_ops that is called
> > right before all the other code in irq_domain_remove(). Next we use it to
> > remove the simulator-specific cleanup function from irq_sim.h - users now
> > can simply use the regular irq_domain_remove().
> >
> > Last two patches show that the new callback isn't limited to the interrupt
> > simulator and can be used to shrink code in real driver too. We introduce
> > a new helper for a common use case of disposing of all mappings before
> > removing the irq_domain and use it in the keystone irqchip driver.
> >
> > The end effect is that we limit the interrupt simulator API to two
> > functions (plus one device managed variant) and zero new structures.
> >
> > v1: https://lkml.org/lkml/2019/8/12/558
> >
> > v1 -> v2:
> > - instead of just making the new data structures opaque for users, remove
> >   them entirely in favor of irq_domain
> > - call irq_set_handler() & irq_domain_reset_irq_data() when unmapping
> >   the simulated interrupt
> > - fix a memory leak in error path
> > - make it possible to use irq_find_matching_fwnode() with the simulator
> >   domain
> > - correctly use irq_create_mapping() and irq_find_mapping(): only use the
> >   former at init-time and the latter at interrupt-time
> >  
> 
> Hi,
> 
> it's been three weeks, so gentle ping on that.
> 
> Or should I resend the entire series with a more elaborate commit
> message for patch 1/6?

I'd resend it now if nothing has happened that I missed.  Merge window
having just closed, it's the perfect time for a rebase on rc1.

thanks,

Jonathan

> 
> Bartosz

Re: [PATCH v2 0/6] irq/irq_sim: try to improve the API

[Bartosz Golaszewski]

pon., 13 kwi 2020 o 19:07 Jonathan Cameron <jic23@kernel.org> napisał(a):
>
> > Hi,
> >
> > it's been three weeks, so gentle ping on that.
> >
> > Or should I resend the entire series with a more elaborate commit
> > message for patch 1/6?
>
> I'd resend it now if nothing has happened that I missed.  Merge window
> having just closed, it's the perfect time for a rebase on rc1.
>

Yeah, I'll resend the first two patches which are less controversial
and then see with the rest of them.

Bart