From 21774fd81a51ec1eccd59caf922d387977acd2aa Mon Sep 17 00:00:00 2001 From: Willem de Bruijn Date: Thu, 15 Oct 2020 14:57:26 -0400 Subject: kernfs: bring names in comments in line with code Fix two stragglers in the comments of the below rename operation. Fixes: adc5e8b58f48 ("kernfs: drop s_ prefix from kernfs_node members") Acked-by: Tejun Heo Signed-off-by: Willem de Bruijn Link: https://lore.kernel.org/r/20201015185726.1386868-1-willemdebruijn.kernel@gmail.com Signed-off-by: Greg Kroah-Hartman --- include/linux/kernfs.h | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) (limited to 'include/linux') diff --git a/include/linux/kernfs.h b/include/linux/kernfs.h index 89f6a4214a70..9e8ca8743c26 100644 --- a/include/linux/kernfs.h +++ b/include/linux/kernfs.h @@ -116,7 +116,7 @@ struct kernfs_elem_attr { * kernfs node is represented by single kernfs_node. Most fields are * private to kernfs and shouldn't be accessed directly by kernfs users. * - * As long as s_count reference is held, the kernfs_node itself is + * As long as count reference is held, the kernfs_node itself is * accessible. Dereferencing elem or any other outer entity requires * active reference. */ -- cgit v1.2.3-71-gd317 From 33c0c9bdf7a59051a654cd98b7d2b48ce0080967 Mon Sep 17 00:00:00 2001 From: Mauro Carvalho Chehab Date: Fri, 23 Oct 2020 18:32:56 +0200 Subject: drivers: base: fix some kernel-doc markups class_create is actually defined at the header. Fix the markup there and add a new one at the right place. While here, also fix some markups for functions that have different names between their prototypes and kernel-doc comments. Signed-off-by: Mauro Carvalho Chehab Link: https://lore.kernel.org/r/2fb6efd6a1f90d69ff73bf579566079cbb051e15.1603469755.git.mchehab+huawei@kernel.org Signed-off-by: Greg Kroah-Hartman --- drivers/base/class.c | 2 +- drivers/base/devres.c | 2 +- drivers/base/firmware_loader/fallback.c | 2 +- include/linux/device/class.h | 14 ++++++++++++++ 4 files changed, 17 insertions(+), 3 deletions(-) (limited to 'include/linux') diff --git a/drivers/base/class.c b/drivers/base/class.c index c3451481194e..7476f393df97 100644 --- a/drivers/base/class.c +++ b/drivers/base/class.c @@ -210,7 +210,7 @@ static void class_create_release(struct class *cls) } /** - * class_create - create a struct class structure + * __class_create - create a struct class structure * @owner: pointer to the module that is to "own" this struct class * @name: pointer to a string for the name of this class. * @key: the lock_class_key for this class; used by mutex lock debugging diff --git a/drivers/base/devres.c b/drivers/base/devres.c index 586e9a75c840..fb9d5289a620 100644 --- a/drivers/base/devres.c +++ b/drivers/base/devres.c @@ -149,7 +149,7 @@ void * __devres_alloc_node(dr_release_t release, size_t size, gfp_t gfp, int nid EXPORT_SYMBOL_GPL(__devres_alloc_node); #else /** - * devres_alloc - Allocate device resource data + * devres_alloc_node - Allocate device resource data * @release: Release function devres will be associated with * @size: Allocation size * @gfp: Allocation flags diff --git a/drivers/base/firmware_loader/fallback.c b/drivers/base/firmware_loader/fallback.c index 4dec4b79ae06..91899d185e31 100644 --- a/drivers/base/firmware_loader/fallback.c +++ b/drivers/base/firmware_loader/fallback.c @@ -128,7 +128,7 @@ static ssize_t timeout_show(struct class *class, struct class_attribute *attr, } /** - * firmware_timeout_store() - set number of seconds to wait for firmware + * timeout_store() - set number of seconds to wait for firmware * @class: device class pointer * @attr: device attribute pointer * @buf: buffer to scan for timeout value diff --git a/include/linux/device/class.h b/include/linux/device/class.h index e8d470c457d1..e61ec5502019 100644 --- a/include/linux/device/class.h +++ b/include/linux/device/class.h @@ -256,6 +256,20 @@ extern void class_destroy(struct class *cls); /* This is a #define to keep the compiler from merging different * instances of the __key variable */ + +/** + * class_create - create a struct class structure + * @owner: pointer to the module that is to "own" this struct class + * @name: pointer to a string for the name of this class. + * + * This is used to create a struct class pointer that can then be used + * in calls to device_create(). + * + * Returns &struct class pointer on success, or ERR_PTR() on error. + * + * Note, the pointer created here is to be destroyed when finished by + * making a call to class_destroy(). + */ #define class_create(owner, name) \ ({ \ static struct lock_class_key __key; \ -- cgit v1.2.3-71-gd317 From 5812b32e01c6d86ba7a84110702b46d8a8531fe9 Mon Sep 17 00:00:00 2001 From: Johan Hovold Date: Mon, 23 Nov 2020 11:23:12 +0100 Subject: of: fix linker-section match-table corruption Specify type alignment when declaring linker-section match-table entries to prevent gcc from increasing alignment and corrupting the various tables with padding (e.g. timers, irqchips, clocks, reserved memory). This is specifically needed on x86 where gcc (typically) aligns larger objects like struct of_device_id with static extent on 32-byte boundaries which at best prevents matching on anything but the first entry. Specifying alignment when declaring variables suppresses this optimisation. Here's a 64-bit example where all entries are corrupt as 16 bytes of padding has been inserted before the first entry: ffffffff8266b4b0 D __clk_of_table ffffffff8266b4c0 d __of_table_fixed_factor_clk ffffffff8266b5a0 d __of_table_fixed_clk ffffffff8266b680 d __clk_of_table_sentinel And here's a 32-bit example where the 8-byte-aligned table happens to be placed on a 32-byte boundary so that all but the first entry are corrupt due to the 28 bytes of padding inserted between entries: 812b3ec0 D __irqchip_of_table 812b3ec0 d __of_table_irqchip1 812b3fa0 d __of_table_irqchip2 812b4080 d __of_table_irqchip3 812b4160 d irqchip_of_match_end Verified on x86 using gcc-9.3 and gcc-4.9 (which uses 64-byte alignment), and on arm using gcc-7.2. Note that there are no in-tree users of these tables on x86 currently (even if they are included in the image). Fixes: 54196ccbe0ba ("of: consolidate linker section OF match table declarations") Fixes: f6e916b82022 ("irqchip: add basic infrastructure") Cc: stable # 3.9 Signed-off-by: Johan Hovold Link: https://lore.kernel.org/r/20201123102319.8090-2-johan@kernel.org Signed-off-by: Greg Kroah-Hartman --- include/linux/of.h | 1 + 1 file changed, 1 insertion(+) (limited to 'include/linux') diff --git a/include/linux/of.h b/include/linux/of.h index 5d51891cbf1a..af655d264f10 100644 --- a/include/linux/of.h +++ b/include/linux/of.h @@ -1300,6 +1300,7 @@ static inline int of_get_available_child_count(const struct device_node *np) #define _OF_DECLARE(table, name, compat, fn, fn_type) \ static const struct of_device_id __of_table_##name \ __used __section("__" #table "_of_table") \ + __aligned(__alignof__(struct of_device_id)) \ = { .compatible = compat, \ .data = (fn == (fn_type)NULL) ? fn : fn } #else -- cgit v1.2.3-71-gd317 From c95d64012ad7de2747923b0caf80e195e940606c Mon Sep 17 00:00:00 2001 From: Saravana Kannan Date: Fri, 20 Nov 2020 18:02:16 -0800 Subject: Revert "driver core: Avoid deferred probe due to fw_devlink_pause/resume()" This reverts commit 2451e746478a6a6e981cfa66b62b791ca93b90c8. fw_devlink_pause/resume() was an incomplete attempt at boot time optimization. That's going to get replaced by a much better optimization at the end of the series. Since fw_devlink_pause/resume() is going away, changes made for that can also go away. Signed-off-by: Saravana Kannan Link: https://lore.kernel.org/r/20201121020232.908850-2-saravanak@google.com Signed-off-by: Greg Kroah-Hartman --- drivers/base/core.c | 21 --------------------- include/linux/device.h | 3 +-- 2 files changed, 1 insertion(+), 23 deletions(-) (limited to 'include/linux') diff --git a/drivers/base/core.c b/drivers/base/core.c index ba5a3cac6571..58c7d17820a7 100644 --- a/drivers/base/core.c +++ b/drivers/base/core.c @@ -51,7 +51,6 @@ static DEFINE_MUTEX(wfs_lock); static LIST_HEAD(deferred_sync); static unsigned int defer_sync_state_count = 1; static unsigned int defer_fw_devlink_count; -static LIST_HEAD(deferred_fw_devlink); static DEFINE_MUTEX(defer_fw_devlink_lock); static bool fw_devlink_is_permissive(void); @@ -1468,12 +1467,6 @@ static void fw_devlink_link_device(struct device *dev) fw_ret = -EAGAIN; } else { fw_ret = -ENODEV; - /* - * defer_hook is not used to add device to deferred_sync list - * until device is bound. Since deferred fw devlink also blocks - * probing, same list hook can be used for deferred_fw_devlink. - */ - list_add_tail(&dev->links.defer_hook, &deferred_fw_devlink); } if (fw_ret == -ENODEV) @@ -1542,9 +1535,6 @@ void fw_devlink_pause(void) */ void fw_devlink_resume(void) { - struct device *dev, *tmp; - LIST_HEAD(probe_list); - mutex_lock(&defer_fw_devlink_lock); if (!defer_fw_devlink_count) { WARN(true, "Unmatched fw_devlink pause/resume!"); @@ -1556,19 +1546,8 @@ void fw_devlink_resume(void) goto out; device_link_add_missing_supplier_links(); - list_splice_tail_init(&deferred_fw_devlink, &probe_list); out: mutex_unlock(&defer_fw_devlink_lock); - - /* - * bus_probe_device() can cause new devices to get added and they'll - * try to grab defer_fw_devlink_lock. So, this needs to be done outside - * the defer_fw_devlink_lock. - */ - list_for_each_entry_safe(dev, tmp, &probe_list, links.defer_hook) { - list_del_init(&dev->links.defer_hook); - bus_probe_device(dev); - } } /* Device links support end. */ diff --git a/include/linux/device.h b/include/linux/device.h index 5ed101be7b2e..da00f8e449bb 100644 --- a/include/linux/device.h +++ b/include/linux/device.h @@ -352,8 +352,7 @@ enum dl_dev_state { * @suppliers: List of links to supplier devices. * @consumers: List of links to consumer devices. * @needs_suppliers: Hook to global list of devices waiting for suppliers. - * @defer_hook: Hook to global list of devices that have deferred sync_state or - * deferred fw_devlink. + * @defer_hook: Hook to global list of devices that have deferred sync_state. * @need_for_probe: If needs_suppliers is on a list, this indicates if the * suppliers are needed for probe or not. * @status: Driver status information. -- cgit v1.2.3-71-gd317 From 3b052a3e30f2eb92dcae9fd89af48d5a13045737 Mon Sep 17 00:00:00 2001 From: Saravana Kannan Date: Fri, 20 Nov 2020 18:02:17 -0800 Subject: Revert "driver core: Rename dev_links_info.defer_sync to defer_hook" This reverts commit ec7bd78498f29680f536451fbdf9464e851273ed. This field rename was done to reuse defer_syc list head for multiple lists. That's not needed anymore and this list head will only be used for defer sync. So revert this patch to avoid conflicts with the other reverts coming after this. Signed-off-by: Saravana Kannan Link: https://lore.kernel.org/r/20201121020232.908850-3-saravanak@google.com Signed-off-by: Greg Kroah-Hartman --- drivers/base/core.c | 22 +++++++++++----------- include/linux/device.h | 4 ++-- 2 files changed, 13 insertions(+), 13 deletions(-) (limited to 'include/linux') diff --git a/drivers/base/core.c b/drivers/base/core.c index 58c7d17820a7..fc4b0bc59935 100644 --- a/drivers/base/core.c +++ b/drivers/base/core.c @@ -959,11 +959,11 @@ static void __device_links_queue_sync_state(struct device *dev, */ dev->state_synced = true; - if (WARN_ON(!list_empty(&dev->links.defer_hook))) + if (WARN_ON(!list_empty(&dev->links.defer_sync))) return; get_device(dev); - list_add_tail(&dev->links.defer_hook, list); + list_add_tail(&dev->links.defer_sync, list); } /** @@ -981,8 +981,8 @@ static void device_links_flush_sync_list(struct list_head *list, { struct device *dev, *tmp; - list_for_each_entry_safe(dev, tmp, list, links.defer_hook) { - list_del_init(&dev->links.defer_hook); + list_for_each_entry_safe(dev, tmp, list, links.defer_sync) { + list_del_init(&dev->links.defer_sync); if (dev != dont_lock_dev) device_lock(dev); @@ -1020,12 +1020,12 @@ void device_links_supplier_sync_state_resume(void) if (defer_sync_state_count) goto out; - list_for_each_entry_safe(dev, tmp, &deferred_sync, links.defer_hook) { + list_for_each_entry_safe(dev, tmp, &deferred_sync, links.defer_sync) { /* * Delete from deferred_sync list before queuing it to - * sync_list because defer_hook is used for both lists. + * sync_list because defer_sync is used for both lists. */ - list_del_init(&dev->links.defer_hook); + list_del_init(&dev->links.defer_sync); __device_links_queue_sync_state(dev, &sync_list); } out: @@ -1043,8 +1043,8 @@ late_initcall(sync_state_resume_initcall); static void __device_links_supplier_defer_sync(struct device *sup) { - if (list_empty(&sup->links.defer_hook) && dev_has_sync_state(sup)) - list_add_tail(&sup->links.defer_hook, &deferred_sync); + if (list_empty(&sup->links.defer_sync) && dev_has_sync_state(sup)) + list_add_tail(&sup->links.defer_sync, &deferred_sync); } static void device_link_drop_managed(struct device_link *link) @@ -1272,7 +1272,7 @@ void device_links_driver_cleanup(struct device *dev) WRITE_ONCE(link->status, DL_STATE_DORMANT); } - list_del_init(&dev->links.defer_hook); + list_del_init(&dev->links.defer_sync); __device_links_no_driver(dev); device_links_write_unlock(); @@ -2405,7 +2405,7 @@ void device_initialize(struct device *dev) INIT_LIST_HEAD(&dev->links.consumers); INIT_LIST_HEAD(&dev->links.suppliers); INIT_LIST_HEAD(&dev->links.needs_suppliers); - INIT_LIST_HEAD(&dev->links.defer_hook); + INIT_LIST_HEAD(&dev->links.defer_sync); dev->links.status = DL_DEV_NO_DRIVER; } EXPORT_SYMBOL_GPL(device_initialize); diff --git a/include/linux/device.h b/include/linux/device.h index da00f8e449bb..1e771ea4dca6 100644 --- a/include/linux/device.h +++ b/include/linux/device.h @@ -352,7 +352,7 @@ enum dl_dev_state { * @suppliers: List of links to supplier devices. * @consumers: List of links to consumer devices. * @needs_suppliers: Hook to global list of devices waiting for suppliers. - * @defer_hook: Hook to global list of devices that have deferred sync_state. + * @defer_sync: Hook to global list of devices that have deferred sync_state. * @need_for_probe: If needs_suppliers is on a list, this indicates if the * suppliers are needed for probe or not. * @status: Driver status information. @@ -361,7 +361,7 @@ struct dev_links_info { struct list_head suppliers; struct list_head consumers; struct list_head needs_suppliers; - struct list_head defer_hook; + struct list_head defer_sync; bool need_for_probe; enum dl_dev_state status; }; -- cgit v1.2.3-71-gd317 From c84b90909e475a2eb4934b4d92fdd10e73e75805 Mon Sep 17 00:00:00 2001 From: Saravana Kannan Date: Fri, 20 Nov 2020 18:02:21 -0800 Subject: Revert "driver core: fw_devlink: Add support for batching fwnode parsing" This reverts commit 716a7a25969003d82ab738179c3f1068a120ed11. The fw_devlink_pause/resume() APIs added by the commit being reverted were a first cut attempt at optimizing boot time. But these APIs don't fully solve the problem and are very fragile (can only be used for the top level devices being added). This series replaces them with a much better optimization that works for all device additions and also has the benefit of reducing the complexity of the firmware (DT, EFI) specific code and abstracting out common code to driver core. Signed-off-by: Saravana Kannan Link: https://lore.kernel.org/r/20201121020232.908850-7-saravanak@google.com Signed-off-by: Greg Kroah-Hartman --- drivers/base/base.h | 1 - drivers/base/core.c | 116 +++---------------------------------------------- drivers/base/dd.c | 8 ---- include/linux/fwnode.h | 2 - 4 files changed, 7 insertions(+), 120 deletions(-) (limited to 'include/linux') diff --git a/drivers/base/base.h b/drivers/base/base.h index c3562adf4789..91cfb8405abd 100644 --- a/drivers/base/base.h +++ b/drivers/base/base.h @@ -156,7 +156,6 @@ extern char *make_class_name(const char *name, struct kobject *kobj); extern int devres_release_all(struct device *dev); extern void device_block_probing(void); extern void device_unblock_probing(void); -extern void driver_deferred_probe_force_trigger(void); /* /sys/devices directory */ extern struct kset *devices_kset; diff --git a/drivers/base/core.c b/drivers/base/core.c index b1189697c29b..670aa452bfe7 100644 --- a/drivers/base/core.c +++ b/drivers/base/core.c @@ -50,9 +50,6 @@ static LIST_HEAD(wait_for_suppliers); static DEFINE_MUTEX(wfs_lock); static LIST_HEAD(deferred_sync); static unsigned int defer_sync_state_count = 1; -static unsigned int defer_fw_devlink_count; -static DEFINE_MUTEX(defer_fw_devlink_lock); -static bool fw_devlink_is_permissive(void); #ifdef CONFIG_SRCU static DEFINE_MUTEX(device_links_lock); @@ -758,7 +755,7 @@ static void device_link_add_missing_supplier_links(void) int ret = fwnode_call_int_op(dev->fwnode, add_links, dev); if (!ret) list_del_init(&dev->links.needs_suppliers); - else if (ret != -ENODEV || fw_devlink_is_permissive()) + else if (ret != -ENODEV) dev->links.need_for_probe = false; } mutex_unlock(&wfs_lock); @@ -1440,116 +1437,17 @@ static void fw_devlink_link_device(struct device *dev) { int fw_ret; - if (!fw_devlink_flags) - return; - - mutex_lock(&defer_fw_devlink_lock); - if (!defer_fw_devlink_count) - device_link_add_missing_supplier_links(); - - /* - * The device's fwnode not having add_links() doesn't affect if other - * consumers can find this device as a supplier. So, this check is - * intentionally placed after device_link_add_missing_supplier_links(). - */ - if (!fwnode_has_op(dev->fwnode, add_links)) - goto out; + device_link_add_missing_supplier_links(); - /* - * If fw_devlink is being deferred, assume all devices have mandatory - * suppliers they need to link to later. Then, when the fw_devlink is - * resumed, all these devices will get a chance to try and link to any - * suppliers they have. - */ - if (!defer_fw_devlink_count) { + if (fw_devlink_flags && fwnode_has_op(dev->fwnode, add_links)) { fw_ret = fwnode_call_int_op(dev->fwnode, add_links, dev); - if (fw_ret == -ENODEV && fw_devlink_is_permissive()) - fw_ret = -EAGAIN; - } else { - fw_ret = -ENODEV; + if (fw_ret == -ENODEV && !fw_devlink_is_permissive()) + device_link_wait_for_mandatory_supplier(dev); + else if (fw_ret) + device_link_wait_for_optional_supplier(dev); } - - if (fw_ret == -ENODEV) - device_link_wait_for_mandatory_supplier(dev); - else if (fw_ret) - device_link_wait_for_optional_supplier(dev); - -out: - mutex_unlock(&defer_fw_devlink_lock); } -/** - * fw_devlink_pause - Pause parsing of fwnode to create device links - * - * Calling this function defers any fwnode parsing to create device links until - * fw_devlink_resume() is called. Both these functions are ref counted and the - * caller needs to match the calls. - * - * While fw_devlink is paused: - * - Any device that is added won't have its fwnode parsed to create device - * links. - * - The probe of the device will also be deferred during this period. - * - Any devices that were already added, but waiting for suppliers won't be - * able to link to newly added devices. - * - * Once fw_devlink_resume(): - * - All the fwnodes that was not parsed will be parsed. - * - All the devices that were deferred probing will be reattempted if they - * aren't waiting for any more suppliers. - * - * This pair of functions, is mainly meant to optimize the parsing of fwnodes - * when a lot of devices that need to link to each other are added in a short - * interval of time. For example, adding all the top level devices in a system. - * - * For example, if N devices are added and: - * - All the consumers are added before their suppliers - * - All the suppliers of the N devices are part of the N devices - * - * Then: - * - * - With the use of fw_devlink_pause() and fw_devlink_resume(), each device - * will only need one parsing of its fwnode because it is guaranteed to find - * all the supplier devices already registered and ready to link to. It won't - * have to do another pass later to find one or more suppliers it couldn't - * find in the first parse of the fwnode. So, we'll only need O(N) fwnode - * parses. - * - * - Without the use of fw_devlink_pause() and fw_devlink_resume(), we would - * end up doing O(N^2) parses of fwnodes because every device that's added is - * guaranteed to trigger a parse of the fwnode of every device added before - * it. This O(N^2) parse is made worse by the fact that when a fwnode of a - * device is parsed, all it descendant devices might need to have their - * fwnodes parsed too (even if the devices themselves aren't added). - */ -void fw_devlink_pause(void) -{ - mutex_lock(&defer_fw_devlink_lock); - defer_fw_devlink_count++; - mutex_unlock(&defer_fw_devlink_lock); -} - -/** fw_devlink_resume - Resume parsing of fwnode to create device links - * - * This function is used in conjunction with fw_devlink_pause() and is ref - * counted. See documentation for fw_devlink_pause() for more details. - */ -void fw_devlink_resume(void) -{ - mutex_lock(&defer_fw_devlink_lock); - if (!defer_fw_devlink_count) { - WARN(true, "Unmatched fw_devlink pause/resume!"); - goto out; - } - - defer_fw_devlink_count--; - if (defer_fw_devlink_count) - goto out; - - device_link_add_missing_supplier_links(); - driver_deferred_probe_force_trigger(); -out: - mutex_unlock(&defer_fw_devlink_lock); -} /* Device links support end. */ int (*platform_notify)(struct device *dev) = NULL; diff --git a/drivers/base/dd.c b/drivers/base/dd.c index b4be35fa7fda..148e81969e04 100644 --- a/drivers/base/dd.c +++ b/drivers/base/dd.c @@ -163,14 +163,6 @@ static bool driver_deferred_probe_enable = false; * again. */ static void driver_deferred_probe_trigger(void) -{ - if (!driver_deferred_probe_enable) - return; - - driver_deferred_probe_force_trigger(); -} - -void driver_deferred_probe_force_trigger(void) { if (!driver_deferred_probe_enable) return; diff --git a/include/linux/fwnode.h b/include/linux/fwnode.h index 9506f8ec0974..e0abafbb17f8 100644 --- a/include/linux/fwnode.h +++ b/include/linux/fwnode.h @@ -171,7 +171,5 @@ struct fwnode_operations { #define get_dev_from_fwnode(fwnode) get_device((fwnode)->dev) extern u32 fw_devlink_get_flags(void); -void fw_devlink_pause(void); -void fw_devlink_resume(void); #endif -- cgit v1.2.3-71-gd317 From 01bb86b380a306bd937c96da36f66429f3362137 Mon Sep 17 00:00:00 2001 From: Saravana Kannan Date: Fri, 20 Nov 2020 18:02:22 -0800 Subject: driver core: Add fwnode_init() There are multiple locations in the kernel where a struct fwnode_handle is initialized. Add fwnode_init() so that we have one way of initializing a fwnode_handle. Acked-by: Rob Herring Signed-off-by: Saravana Kannan Link: https://lore.kernel.org/r/20201121020232.908850-8-saravanak@google.com Signed-off-by: Greg Kroah-Hartman --- drivers/acpi/property.c | 2 +- drivers/acpi/scan.c | 2 +- drivers/base/swnode.c | 2 +- drivers/firmware/efi/efi-init.c | 8 ++++---- include/linux/fwnode.h | 6 ++++++ include/linux/of.h | 2 +- kernel/irq/irqdomain.c | 2 +- 7 files changed, 15 insertions(+), 9 deletions(-) (limited to 'include/linux') diff --git a/drivers/acpi/property.c b/drivers/acpi/property.c index d04de10a63e4..24e87b630573 100644 --- a/drivers/acpi/property.c +++ b/drivers/acpi/property.c @@ -76,7 +76,7 @@ static bool acpi_nondev_subnode_extract(const union acpi_object *desc, return false; dn->name = link->package.elements[0].string.pointer; - dn->fwnode.ops = &acpi_data_fwnode_ops; + fwnode_init(&dn->fwnode, &acpi_data_fwnode_ops); dn->parent = parent; INIT_LIST_HEAD(&dn->data.properties); INIT_LIST_HEAD(&dn->data.subnodes); diff --git a/drivers/acpi/scan.c b/drivers/acpi/scan.c index a896e5e87c93..0ac19f9274b8 100644 --- a/drivers/acpi/scan.c +++ b/drivers/acpi/scan.c @@ -1589,7 +1589,7 @@ void acpi_init_device_object(struct acpi_device *device, acpi_handle handle, device->device_type = type; device->handle = handle; device->parent = acpi_bus_get_parent(handle); - device->fwnode.ops = &acpi_device_fwnode_ops; + fwnode_init(&device->fwnode, &acpi_device_fwnode_ops); acpi_set_device_status(device, sta); acpi_device_get_busid(device); acpi_set_pnp_ids(handle, &device->pnp, type); diff --git a/drivers/base/swnode.c b/drivers/base/swnode.c index 010828fc785b..4a4b2008fbc2 100644 --- a/drivers/base/swnode.c +++ b/drivers/base/swnode.c @@ -653,7 +653,7 @@ swnode_register(const struct software_node *node, struct swnode *parent, swnode->parent = parent; swnode->allocated = allocated; swnode->kobj.kset = swnode_kset; - swnode->fwnode.ops = &software_node_ops; + fwnode_init(&swnode->fwnode, &software_node_ops); ida_init(&swnode->child_ids); INIT_LIST_HEAD(&swnode->entry); diff --git a/drivers/firmware/efi/efi-init.c b/drivers/firmware/efi/efi-init.c index f55a92ff12c0..b148f1459fb3 100644 --- a/drivers/firmware/efi/efi-init.c +++ b/drivers/firmware/efi/efi-init.c @@ -359,9 +359,7 @@ static const struct fwnode_operations efifb_fwnode_ops = { .add_links = efifb_add_links, }; -static struct fwnode_handle efifb_fwnode = { - .ops = &efifb_fwnode_ops, -}; +static struct fwnode_handle efifb_fwnode; static int __init register_gop_device(void) { @@ -375,8 +373,10 @@ static int __init register_gop_device(void) if (!pd) return -ENOMEM; - if (IS_ENABLED(CONFIG_PCI)) + if (IS_ENABLED(CONFIG_PCI)) { + fwnode_init(&efifb_fwnode, &efifb_fwnode_ops); pd->dev.fwnode = &efifb_fwnode; + } err = platform_device_add_data(pd, &screen_info, sizeof(screen_info)); if (err) diff --git a/include/linux/fwnode.h b/include/linux/fwnode.h index e0abafbb17f8..5589799708b5 100644 --- a/include/linux/fwnode.h +++ b/include/linux/fwnode.h @@ -170,6 +170,12 @@ struct fwnode_operations { } while (false) #define get_dev_from_fwnode(fwnode) get_device((fwnode)->dev) +static inline void fwnode_init(struct fwnode_handle *fwnode, + const struct fwnode_operations *ops) +{ + fwnode->ops = ops; +} + extern u32 fw_devlink_get_flags(void); #endif diff --git a/include/linux/of.h b/include/linux/of.h index af655d264f10..df71a3a1bb8d 100644 --- a/include/linux/of.h +++ b/include/linux/of.h @@ -108,7 +108,7 @@ static inline void of_node_init(struct device_node *node) #if defined(CONFIG_OF_KOBJ) kobject_init(&node->kobj, &of_node_ktype); #endif - node->fwnode.ops = &of_fwnode_ops; + fwnode_init(&node->fwnode, &of_fwnode_ops); } #if defined(CONFIG_OF_KOBJ) diff --git a/kernel/irq/irqdomain.c b/kernel/irq/irqdomain.c index cf8b374b892d..06fce7e39033 100644 --- a/kernel/irq/irqdomain.c +++ b/kernel/irq/irqdomain.c @@ -91,7 +91,7 @@ struct fwnode_handle *__irq_domain_alloc_fwnode(unsigned int type, int id, fwid->type = type; fwid->name = n; fwid->pa = pa; - fwid->fwnode.ops = &irqchip_fwnode_ops; + fwnode_init(&fwid->fwnode, &irqchip_fwnode_ops); return &fwid->fwnode; } EXPORT_SYMBOL_GPL(__irq_domain_alloc_fwnode); -- cgit v1.2.3-71-gd317 From 7b337cb3ebde384cba7405b61dfb84200bf623bf Mon Sep 17 00:00:00 2001 From: Saravana Kannan Date: Fri, 20 Nov 2020 18:02:23 -0800 Subject: driver core: Add fwnode link support Add support for creating supplier-consumer links between fwnodes. It is intended for internal use the driver core and generic firmware support code (eg. Device Tree, ACPI), so it is simple by design and the API provided is limited. Acked-by: Rob Herring Signed-off-by: Saravana Kannan Link: https://lore.kernel.org/r/20201121020232.908850-9-saravanak@google.com Signed-off-by: Greg Kroah-Hartman --- drivers/base/core.c | 98 ++++++++++++++++++++++++++++++++++++++++++++++++++ drivers/of/dynamic.c | 1 + include/linux/fwnode.h | 14 ++++++++ 3 files changed, 113 insertions(+) (limited to 'include/linux') diff --git a/drivers/base/core.c b/drivers/base/core.c index 670aa452bfe7..972d42dedfc8 100644 --- a/drivers/base/core.c +++ b/drivers/base/core.c @@ -50,6 +50,104 @@ static LIST_HEAD(wait_for_suppliers); static DEFINE_MUTEX(wfs_lock); static LIST_HEAD(deferred_sync); static unsigned int defer_sync_state_count = 1; +static DEFINE_MUTEX(fwnode_link_lock); + +/** + * fwnode_link_add - Create a link between two fwnode_handles. + * @con: Consumer end of the link. + * @sup: Supplier end of the link. + * + * Create a fwnode link between fwnode handles @con and @sup. The fwnode link + * represents the detail that the firmware lists @sup fwnode as supplying a + * resource to @con. + * + * The driver core will use the fwnode link to create a device link between the + * two device objects corresponding to @con and @sup when they are created. The + * driver core will automatically delete the fwnode link between @con and @sup + * after doing that. + * + * Attempts to create duplicate links between the same pair of fwnode handles + * are ignored and there is no reference counting. + */ +int fwnode_link_add(struct fwnode_handle *con, struct fwnode_handle *sup) +{ + struct fwnode_link *link; + int ret = 0; + + mutex_lock(&fwnode_link_lock); + + list_for_each_entry(link, &sup->consumers, s_hook) + if (link->consumer == con) + goto out; + + link = kzalloc(sizeof(*link), GFP_KERNEL); + if (!link) { + ret = -ENOMEM; + goto out; + } + + link->supplier = sup; + INIT_LIST_HEAD(&link->s_hook); + link->consumer = con; + INIT_LIST_HEAD(&link->c_hook); + + list_add(&link->s_hook, &sup->consumers); + list_add(&link->c_hook, &con->suppliers); +out: + mutex_unlock(&fwnode_link_lock); + + return ret; +} + +/** + * fwnode_links_purge_suppliers - Delete all supplier links of fwnode_handle. + * @fwnode: fwnode whose supplier links need to be deleted + * + * Deletes all supplier links connecting directly to @fwnode. + */ +static void fwnode_links_purge_suppliers(struct fwnode_handle *fwnode) +{ + struct fwnode_link *link, *tmp; + + mutex_lock(&fwnode_link_lock); + list_for_each_entry_safe(link, tmp, &fwnode->suppliers, c_hook) { + list_del(&link->s_hook); + list_del(&link->c_hook); + kfree(link); + } + mutex_unlock(&fwnode_link_lock); +} + +/** + * fwnode_links_purge_consumers - Delete all consumer links of fwnode_handle. + * @fwnode: fwnode whose consumer links need to be deleted + * + * Deletes all consumer links connecting directly to @fwnode. + */ +static void fwnode_links_purge_consumers(struct fwnode_handle *fwnode) +{ + struct fwnode_link *link, *tmp; + + mutex_lock(&fwnode_link_lock); + list_for_each_entry_safe(link, tmp, &fwnode->consumers, s_hook) { + list_del(&link->s_hook); + list_del(&link->c_hook); + kfree(link); + } + mutex_unlock(&fwnode_link_lock); +} + +/** + * fwnode_links_purge - Delete all links connected to a fwnode_handle. + * @fwnode: fwnode whose links needs to be deleted + * + * Deletes all links connecting directly to a fwnode. + */ +void fwnode_links_purge(struct fwnode_handle *fwnode) +{ + fwnode_links_purge_suppliers(fwnode); + fwnode_links_purge_consumers(fwnode); +} #ifdef CONFIG_SRCU static DEFINE_MUTEX(device_links_lock); diff --git a/drivers/of/dynamic.c b/drivers/of/dynamic.c index fe64430b438a..9a824decf61f 100644 --- a/drivers/of/dynamic.c +++ b/drivers/of/dynamic.c @@ -356,6 +356,7 @@ void of_node_release(struct kobject *kobj) property_list_free(node->properties); property_list_free(node->deadprops); + fwnode_links_purge(of_fwnode_handle(node)); kfree(node->full_name); kfree(node->data); diff --git a/include/linux/fwnode.h b/include/linux/fwnode.h index 5589799708b5..b88365187347 100644 --- a/include/linux/fwnode.h +++ b/include/linux/fwnode.h @@ -10,6 +10,7 @@ #define _LINUX_FWNODE_H_ #include +#include struct fwnode_operations; struct device; @@ -18,6 +19,15 @@ struct fwnode_handle { struct fwnode_handle *secondary; const struct fwnode_operations *ops; struct device *dev; + struct list_head suppliers; + struct list_head consumers; +}; + +struct fwnode_link { + struct fwnode_handle *supplier; + struct list_head s_hook; + struct fwnode_handle *consumer; + struct list_head c_hook; }; /** @@ -174,8 +184,12 @@ static inline void fwnode_init(struct fwnode_handle *fwnode, const struct fwnode_operations *ops) { fwnode->ops = ops; + INIT_LIST_HEAD(&fwnode->consumers); + INIT_LIST_HEAD(&fwnode->suppliers); } extern u32 fw_devlink_get_flags(void); +int fwnode_link_add(struct fwnode_handle *con, struct fwnode_handle *sup); +void fwnode_links_purge(struct fwnode_handle *fwnode); #endif -- cgit v1.2.3-71-gd317 From b5d3e2fbcb10957521af14c4256cd0e5f68b9234 Mon Sep 17 00:00:00 2001 From: Saravana Kannan Date: Fri, 20 Nov 2020 18:02:25 -0800 Subject: device property: Add fwnode_is_ancestor_of() and fwnode_get_next_parent_dev() Add fwnode_is_ancestor_of() helper function to check if a fwnode is an ancestor of another fwnode. Add fwnode_get_next_parent_dev() helper function that take as input a fwnode and finds the closest ancestor fwnode that has a corresponding struct device and returns that struct device. Signed-off-by: Saravana Kannan Link: https://lore.kernel.org/r/20201121020232.908850-11-saravanak@google.com Signed-off-by: Greg Kroah-Hartman --- drivers/base/property.c | 52 ++++++++++++++++++++++++++++++++++++++++++++++++ include/linux/property.h | 3 +++ 2 files changed, 55 insertions(+) (limited to 'include/linux') diff --git a/drivers/base/property.c b/drivers/base/property.c index 4c43d30145c6..35b95c6ac0c6 100644 --- a/drivers/base/property.c +++ b/drivers/base/property.c @@ -614,6 +614,31 @@ struct fwnode_handle *fwnode_get_next_parent(struct fwnode_handle *fwnode) } EXPORT_SYMBOL_GPL(fwnode_get_next_parent); +/** + * fwnode_get_next_parent_dev - Find device of closest ancestor fwnode + * @fwnode: firmware node + * + * Given a firmware node (@fwnode), this function finds its closest ancestor + * firmware node that has a corresponding struct device and returns that struct + * device. + * + * The caller of this function is expected to call put_device() on the returned + * device when they are done. + */ +struct device *fwnode_get_next_parent_dev(struct fwnode_handle *fwnode) +{ + struct device *dev = NULL; + + fwnode_handle_get(fwnode); + do { + fwnode = fwnode_get_next_parent(fwnode); + if (fwnode) + dev = get_dev_from_fwnode(fwnode); + } while (fwnode && !dev); + fwnode_handle_put(fwnode); + return dev; +} + /** * fwnode_count_parents - Return the number of parents a node has * @fwnode: The node the parents of which are to be counted @@ -660,6 +685,33 @@ struct fwnode_handle *fwnode_get_nth_parent(struct fwnode_handle *fwnode, } EXPORT_SYMBOL_GPL(fwnode_get_nth_parent); +/** + * fwnode_is_ancestor_of - Test if @test_ancestor is ancestor of @test_child + * @test_ancestor: Firmware which is tested for being an ancestor + * @test_child: Firmware which is tested for being the child + * + * A node is considered an ancestor of itself too. + * + * Returns true if @test_ancestor is an ancestor of @test_child. + * Otherwise, returns false. + */ +bool fwnode_is_ancestor_of(struct fwnode_handle *test_ancestor, + struct fwnode_handle *test_child) +{ + if (!test_ancestor) + return false; + + fwnode_handle_get(test_child); + while (test_child) { + if (test_child == test_ancestor) { + fwnode_handle_put(test_child); + return true; + } + test_child = fwnode_get_next_parent(test_child); + } + return false; +} + /** * fwnode_get_next_child_node - Return the next child node handle for a node * @fwnode: Firmware node to find the next child node for. diff --git a/include/linux/property.h b/include/linux/property.h index 2d4542629d80..0a9001fe7aea 100644 --- a/include/linux/property.h +++ b/include/linux/property.h @@ -85,9 +85,12 @@ const char *fwnode_get_name_prefix(const struct fwnode_handle *fwnode); struct fwnode_handle *fwnode_get_parent(const struct fwnode_handle *fwnode); struct fwnode_handle *fwnode_get_next_parent( struct fwnode_handle *fwnode); +struct device *fwnode_get_next_parent_dev(struct fwnode_handle *fwnode); unsigned int fwnode_count_parents(const struct fwnode_handle *fwn); struct fwnode_handle *fwnode_get_nth_parent(struct fwnode_handle *fwn, unsigned int depth); +bool fwnode_is_ancestor_of(struct fwnode_handle *test_ancestor, + struct fwnode_handle *test_child); struct fwnode_handle *fwnode_get_next_child_node( const struct fwnode_handle *fwnode, struct fwnode_handle *child); struct fwnode_handle *fwnode_get_next_available_child_node( -- cgit v1.2.3-71-gd317 From 04f63c213b671d89db35f4239f57fa1edeb736a8 Mon Sep 17 00:00:00 2001 From: Saravana Kannan Date: Fri, 20 Nov 2020 18:02:26 -0800 Subject: driver core: Redefine the meaning of fwnode_operations.add_links() Change the meaning of fwnode_operations.add_links() to just create fwnode links by parsing the properties of a given fwnode. This patch doesn't actually make any code changes. To keeps things more digestable, the actual functional changes come in later patches in this series. Signed-off-by: Saravana Kannan Link: https://lore.kernel.org/r/20201121020232.908850-12-saravanak@google.com Signed-off-by: Greg Kroah-Hartman --- drivers/firmware/efi/efi-init.c | 2 +- include/linux/fwnode.h | 42 +++-------------------------------------- 2 files changed, 4 insertions(+), 40 deletions(-) (limited to 'include/linux') diff --git a/drivers/firmware/efi/efi-init.c b/drivers/firmware/efi/efi-init.c index b148f1459fb3..65bb97c391b0 100644 --- a/drivers/firmware/efi/efi-init.c +++ b/drivers/firmware/efi/efi-init.c @@ -316,7 +316,7 @@ static struct device_node *find_pci_overlap_node(void) * resource reservation conflict on the memory window that the efifb * framebuffer steals from the PCIe host bridge. */ -static int efifb_add_links(const struct fwnode_handle *fwnode, +static int efifb_add_links(struct fwnode_handle *fwnode, struct device *dev) { struct device_node *sup_np; diff --git a/include/linux/fwnode.h b/include/linux/fwnode.h index b88365187347..942a6bb18201 100644 --- a/include/linux/fwnode.h +++ b/include/linux/fwnode.h @@ -78,44 +78,8 @@ struct fwnode_reference_args { * endpoint node. * @graph_get_port_parent: Return the parent node of a port node. * @graph_parse_endpoint: Parse endpoint for port and endpoint id. - * @add_links: Called after the device corresponding to the fwnode is added - * using device_add(). The function is expected to create device - * links to all the suppliers of the device that are available at - * the time this function is called. The function must NOT stop - * at the first failed device link if other unlinked supplier - * devices are present in the system. This is necessary for the - * driver/bus sync_state() callbacks to work correctly. - * - * For example, say Device-C depends on suppliers Device-S1 and - * Device-S2 and the dependency is listed in that order in the - * firmware. Say, S1 gets populated from the firmware after - * late_initcall_sync(). Say S2 is populated and probed way - * before that in device_initcall(). When C is populated, if this - * add_links() function doesn't continue past a "failed linking to - * S1" and continue linking C to S2, then S2 will get a - * sync_state() callback before C is probed. This is because from - * the perspective of S2, C was never a consumer when its - * sync_state() evaluation is done. To avoid this, the add_links() - * function has to go through all available suppliers of the - * device (that corresponds to this fwnode) and link to them - * before returning. - * - * If some suppliers are not yet available (indicated by an error - * return value), this function will be called again when other - * devices are added to allow creating device links to any newly - * available suppliers. - * - * Return 0 if device links have been successfully created to all - * the known suppliers of this device or if the supplier - * information is not known. - * - * Return -ENODEV if the suppliers needed for probing this device - * have not been registered yet (because device links can only be - * created to devices registered with the driver core). - * - * Return -EAGAIN if some of the suppliers of this device have not - * been registered yet, but none of those suppliers are necessary - * for probing the device. + * @add_links: Create fwnode links to all the suppliers of the fwnode. Return + * zero on success, a negative error code otherwise. */ struct fwnode_operations { struct fwnode_handle *(*get)(struct fwnode_handle *fwnode); @@ -155,7 +119,7 @@ struct fwnode_operations { (*graph_get_port_parent)(struct fwnode_handle *fwnode); int (*graph_parse_endpoint)(const struct fwnode_handle *fwnode, struct fwnode_endpoint *endpoint); - int (*add_links)(const struct fwnode_handle *fwnode, + int (*add_links)(struct fwnode_handle *fwnode, struct device *dev); }; -- cgit v1.2.3-71-gd317 From c2c724c868c42c5166bf7aa644dd0a0c8d30b47a Mon Sep 17 00:00:00 2001 From: Saravana Kannan Date: Fri, 20 Nov 2020 18:02:27 -0800 Subject: driver core: Add fw_devlink_parse_fwtree() This function is a wrapper around fwnode_operations.add_links(). This function parses each node in a fwnode tree and create fwnode links for each of those nodes. The information for creating the fwnode links (the supplier and consumer fwnode) is obtained by parsing the properties in each of the fwnodes. This function also ensures that no fwnode is parsed more than once by marking the fwnodes as parsed. Signed-off-by: Saravana Kannan Link: https://lore.kernel.org/r/20201121020232.908850-13-saravanak@google.com Signed-off-by: Greg Kroah-Hartman --- drivers/base/core.c | 19 +++++++++++++++++++ include/linux/fwnode.h | 8 ++++++++ 2 files changed, 27 insertions(+) (limited to 'include/linux') diff --git a/drivers/base/core.c b/drivers/base/core.c index edde79fc3d33..92a2dc355d13 100644 --- a/drivers/base/core.c +++ b/drivers/base/core.c @@ -1542,6 +1542,25 @@ static bool fw_devlink_is_permissive(void) return fw_devlink_flags == DL_FLAG_SYNC_STATE_ONLY; } +static void fw_devlink_parse_fwnode(struct fwnode_handle *fwnode) +{ + if (fwnode->flags & FWNODE_FLAG_LINKS_ADDED) + return; + + fwnode_call_int_op(fwnode, add_links, NULL); + fwnode->flags |= FWNODE_FLAG_LINKS_ADDED; +} + +static void fw_devlink_parse_fwtree(struct fwnode_handle *fwnode) +{ + struct fwnode_handle *child = NULL; + + fw_devlink_parse_fwnode(fwnode); + + while ((child = fwnode_get_next_available_child_node(fwnode, child))) + fw_devlink_parse_fwtree(child); +} + static void fw_devlink_link_device(struct device *dev) { int fw_ret; diff --git a/include/linux/fwnode.h b/include/linux/fwnode.h index 942a6bb18201..ffa9129182a6 100644 --- a/include/linux/fwnode.h +++ b/include/linux/fwnode.h @@ -15,12 +15,20 @@ struct fwnode_operations; struct device; +/* + * fwnode link flags + * + * LINKS_ADDED: The fwnode has already be parsed to add fwnode links. + */ +#define FWNODE_FLAG_LINKS_ADDED BIT(0) + struct fwnode_handle { struct fwnode_handle *secondary; const struct fwnode_operations *ops; struct device *dev; struct list_head suppliers; struct list_head consumers; + u8 flags; }; struct fwnode_link { -- cgit v1.2.3-71-gd317 From f9aa460672c9c56896cdc12a521159e3e67000ba Mon Sep 17 00:00:00 2001 From: Saravana Kannan Date: Fri, 20 Nov 2020 18:02:31 -0800 Subject: driver core: Refactor fw_devlink feature The current implementation of fw_devlink is very inefficient because it tries to get away without creating fwnode links in the name of saving memory usage. Past attempts to optimize runtime at the cost of memory usage were blocked with request for data showing that the optimization made significant improvement for real world scenarios. We have those scenarios now. There have been several reports of boot time increase in the order of seconds in this thread [1]. Several OEMs and SoC manufacturers have also privately reported significant (350-400ms) increase in boot time due to all the parsing done by fw_devlink. So this patch uses all the setup done by the previous patches in this series to refactor fw_devlink to be more efficient. Most of the code has been moved out of firmware specific (DT mostly) code into driver core. This brings the following benefits: - Instead of parsing the device tree multiple times during bootup, fw_devlink parses each fwnode node/property only once and creates fwnode links. The rest of the fw_devlink code then just looks at these fwnode links to do rest of the work. - Makes it much easier to debug probe issue due to fw_devlink in the future. fw_devlink=on blocks the probing of devices if they depend on a device that hasn't been added yet. With this refactor, it'll be very easy to tell what that device is because we now have a reference to the fwnode of the device. - Much easier to add fw_devlink support to ACPI and other firmware types. A refactor to move the common bits from DT specific code to driver core was in my TODO list as a prerequisite to adding ACPI support to fw_devlink. This series gets that done. [1] - https://lore.kernel.org/linux-omap/ea02f57e-871d-cd16-4418-c1da4bbc4696@ti.com/ Tested-by: Laurent Pinchart Tested-by: Grygorii Strashko Signed-off-by: Saravana Kannan Link: https://lore.kernel.org/r/20201121020232.908850-17-saravanak@google.com Signed-off-by: Greg Kroah-Hartman --- drivers/base/core.c | 325 ++++++++++++++++++++++++++++++++++++------------- include/linux/device.h | 5 - 2 files changed, 238 insertions(+), 92 deletions(-) (limited to 'include/linux') diff --git a/drivers/base/core.c b/drivers/base/core.c index 8a973d9601d3..9edf9084fc98 100644 --- a/drivers/base/core.c +++ b/drivers/base/core.c @@ -46,8 +46,6 @@ early_param("sysfs.deprecated", sysfs_deprecated_setup); #endif /* Device links support. */ -static LIST_HEAD(wait_for_suppliers); -static DEFINE_MUTEX(wfs_lock); static LIST_HEAD(deferred_sync); static unsigned int defer_sync_state_count = 1; static DEFINE_MUTEX(fwnode_link_lock); @@ -803,74 +801,6 @@ out: } EXPORT_SYMBOL_GPL(device_link_add); -/** - * device_link_wait_for_supplier - Add device to wait_for_suppliers list - * @consumer: Consumer device - * - * Marks the @consumer device as waiting for suppliers to become available by - * adding it to the wait_for_suppliers list. The consumer device will never be - * probed until it's removed from the wait_for_suppliers list. - * - * The caller is responsible for adding the links to the supplier devices once - * they are available and removing the @consumer device from the - * wait_for_suppliers list once links to all the suppliers have been created. - * - * This function is NOT meant to be called from the probe function of the - * consumer but rather from code that creates/adds the consumer device. - */ -static void device_link_wait_for_supplier(struct device *consumer, - bool need_for_probe) -{ - mutex_lock(&wfs_lock); - list_add_tail(&consumer->links.needs_suppliers, &wait_for_suppliers); - consumer->links.need_for_probe = need_for_probe; - mutex_unlock(&wfs_lock); -} - -static void device_link_wait_for_mandatory_supplier(struct device *consumer) -{ - device_link_wait_for_supplier(consumer, true); -} - -static void device_link_wait_for_optional_supplier(struct device *consumer) -{ - device_link_wait_for_supplier(consumer, false); -} - -/** - * device_link_add_missing_supplier_links - Add links from consumer devices to - * supplier devices, leaving any - * consumer with inactive suppliers on - * the wait_for_suppliers list - * - * Loops through all consumers waiting on suppliers and tries to add all their - * supplier links. If that succeeds, the consumer device is removed from - * wait_for_suppliers list. Otherwise, they are left in the wait_for_suppliers - * list. Devices left on the wait_for_suppliers list will not be probed. - * - * The fwnode add_links callback is expected to return 0 if it has found and - * added all the supplier links for the consumer device. It should return an - * error if it isn't able to do so. - * - * The caller of device_link_wait_for_supplier() is expected to call this once - * it's aware of potential suppliers becoming available. - */ -static void device_link_add_missing_supplier_links(void) -{ - struct device *dev, *tmp; - - mutex_lock(&wfs_lock); - list_for_each_entry_safe(dev, tmp, &wait_for_suppliers, - links.needs_suppliers) { - int ret = fwnode_call_int_op(dev->fwnode, add_links, dev); - if (!ret) - list_del_init(&dev->links.needs_suppliers); - else if (ret != -ENODEV) - dev->links.need_for_probe = false; - } - mutex_unlock(&wfs_lock); -} - #ifdef CONFIG_SRCU static void __device_link_del(struct kref *kref) { @@ -1195,9 +1125,8 @@ void device_links_driver_bound(struct device *dev) * the device links it needs to or make new device links as it needs * them. So, it no longer needs to wait on any suppliers. */ - mutex_lock(&wfs_lock); - list_del_init(&dev->links.needs_suppliers); - mutex_unlock(&wfs_lock); + if (dev->fwnode && dev->fwnode->dev == dev) + fwnode_links_purge_suppliers(dev->fwnode); device_remove_file(dev, &dev_attr_waiting_for_supplier); device_links_write_lock(); @@ -1488,10 +1417,6 @@ static void device_links_purge(struct device *dev) if (dev->class == &devlink_class) return; - mutex_lock(&wfs_lock); - list_del_init(&dev->links.needs_suppliers); - mutex_unlock(&wfs_lock); - /* * Delete all of the remaining links from this device to any other * devices (either consumers or suppliers). @@ -1561,19 +1486,246 @@ static void fw_devlink_parse_fwtree(struct fwnode_handle *fwnode) fw_devlink_parse_fwtree(child); } -static void fw_devlink_link_device(struct device *dev) +/** + * fw_devlink_create_devlink - Create a device link from a consumer to fwnode + * @con - Consumer device for the device link + * @sup_handle - fwnode handle of supplier + * + * This function will try to create a device link between the consumer device + * @con and the supplier device represented by @sup_handle. + * + * The supplier has to be provided as a fwnode because incorrect cycles in + * fwnode links can sometimes cause the supplier device to never be created. + * This function detects such cases and returns an error if it cannot create a + * device link from the consumer to a missing supplier. + * + * Returns, + * 0 on successfully creating a device link + * -EINVAL if the device link cannot be created as expected + * -EAGAIN if the device link cannot be created right now, but it may be + * possible to do that in the future + */ +static int fw_devlink_create_devlink(struct device *con, + struct fwnode_handle *sup_handle, u32 flags) +{ + struct device *sup_dev; + int ret = 0; + + sup_dev = get_dev_from_fwnode(sup_handle); + if (sup_dev) { + /* + * If this fails, it is due to cycles in device links. Just + * give up on this link and treat it as invalid. + */ + if (!device_link_add(con, sup_dev, flags)) + ret = -EINVAL; + + goto out; + } + + /* + * DL_FLAG_SYNC_STATE_ONLY doesn't block probing and supports + * cycles. So cycle detection isn't necessary and shouldn't be + * done. + */ + if (flags & DL_FLAG_SYNC_STATE_ONLY) + return -EAGAIN; + + /* + * If we can't find the supplier device from its fwnode, it might be + * due to a cyclic dependency between fwnodes. Some of these cycles can + * be broken by applying logic. Check for these types of cycles and + * break them so that devices in the cycle probe properly. + * + * If the supplier's parent is dependent on the consumer, then + * the consumer-supplier dependency is a false dependency. So, + * treat it as an invalid link. + */ + sup_dev = fwnode_get_next_parent_dev(sup_handle); + if (sup_dev && device_is_dependent(con, sup_dev)) { + dev_dbg(con, "Not linking to %pfwP - False link\n", + sup_handle); + ret = -EINVAL; + } else { + /* + * Can't check for cycles or no cycles. So let's try + * again later. + */ + ret = -EAGAIN; + } + +out: + put_device(sup_dev); + return ret; +} + +/** + * __fw_devlink_link_to_consumers - Create device links to consumers of a device + * @dev - Device that needs to be linked to its consumers + * + * This function looks at all the consumer fwnodes of @dev and creates device + * links between the consumer device and @dev (supplier). + * + * If the consumer device has not been added yet, then this function creates a + * SYNC_STATE_ONLY link between @dev (supplier) and the closest ancestor device + * of the consumer fwnode. This is necessary to make sure @dev doesn't get a + * sync_state() callback before the real consumer device gets to be added and + * then probed. + * + * Once device links are created from the real consumer to @dev (supplier), the + * fwnode links are deleted. + */ +static void __fw_devlink_link_to_consumers(struct device *dev) +{ + struct fwnode_handle *fwnode = dev->fwnode; + struct fwnode_link *link, *tmp; + + list_for_each_entry_safe(link, tmp, &fwnode->consumers, s_hook) { + u32 dl_flags = fw_devlink_get_flags(); + struct device *con_dev; + bool own_link = true; + int ret; + + con_dev = get_dev_from_fwnode(link->consumer); + /* + * If consumer device is not available yet, make a "proxy" + * SYNC_STATE_ONLY link from the consumer's parent device to + * the supplier device. This is necessary to make sure the + * supplier doesn't get a sync_state() callback before the real + * consumer can create a device link to the supplier. + * + * This proxy link step is needed to handle the case where the + * consumer's parent device is added before the supplier. + */ + if (!con_dev) { + con_dev = fwnode_get_next_parent_dev(link->consumer); + /* + * However, if the consumer's parent device is also the + * parent of the supplier, don't create a + * consumer-supplier link from the parent to its child + * device. Such a dependency is impossible. + */ + if (con_dev && + fwnode_is_ancestor_of(con_dev->fwnode, fwnode)) { + put_device(con_dev); + con_dev = NULL; + } else { + own_link = false; + dl_flags = DL_FLAG_SYNC_STATE_ONLY; + } + } + + if (!con_dev) + continue; + + ret = fw_devlink_create_devlink(con_dev, fwnode, dl_flags); + put_device(con_dev); + if (!own_link || ret == -EAGAIN) + continue; + + list_del(&link->s_hook); + list_del(&link->c_hook); + kfree(link); + } +} + +/** + * __fw_devlink_link_to_suppliers - Create device links to suppliers of a device + * @dev - The consumer device that needs to be linked to its suppliers + * @fwnode - Root of the fwnode tree that is used to create device links + * + * This function looks at all the supplier fwnodes of fwnode tree rooted at + * @fwnode and creates device links between @dev (consumer) and all the + * supplier devices of the entire fwnode tree at @fwnode. + * + * The function creates normal (non-SYNC_STATE_ONLY) device links between @dev + * and the real suppliers of @dev. Once these device links are created, the + * fwnode links are deleted. When such device links are successfully created, + * this function is called recursively on those supplier devices. This is + * needed to detect and break some invalid cycles in fwnode links. See + * fw_devlink_create_devlink() for more details. + * + * In addition, it also looks at all the suppliers of the entire fwnode tree + * because some of the child devices of @dev that have not been added yet + * (because @dev hasn't probed) might already have their suppliers added to + * driver core. So, this function creates SYNC_STATE_ONLY device links between + * @dev (consumer) and these suppliers to make sure they don't execute their + * sync_state() callbacks before these child devices have a chance to create + * their device links. The fwnode links that correspond to the child devices + * aren't delete because they are needed later to create the device links + * between the real consumer and supplier devices. + */ +static void __fw_devlink_link_to_suppliers(struct device *dev, + struct fwnode_handle *fwnode) { - int fw_ret; + bool own_link = (dev->fwnode == fwnode); + struct fwnode_link *link, *tmp; + struct fwnode_handle *child = NULL; + u32 dl_flags; + + if (own_link) + dl_flags = fw_devlink_get_flags(); + else + dl_flags = DL_FLAG_SYNC_STATE_ONLY; - device_link_add_missing_supplier_links(); + list_for_each_entry_safe(link, tmp, &fwnode->suppliers, c_hook) { + int ret; + struct device *sup_dev; + struct fwnode_handle *sup = link->supplier; + + ret = fw_devlink_create_devlink(dev, sup, dl_flags); + if (!own_link || ret == -EAGAIN) + continue; - if (fw_devlink_flags && fwnode_has_op(dev->fwnode, add_links)) { - fw_ret = fwnode_call_int_op(dev->fwnode, add_links, dev); - if (fw_ret == -ENODEV && !fw_devlink_is_permissive()) - device_link_wait_for_mandatory_supplier(dev); - else if (fw_ret) - device_link_wait_for_optional_supplier(dev); + list_del(&link->s_hook); + list_del(&link->c_hook); + kfree(link); + + /* If no device link was created, nothing more to do. */ + if (ret) + continue; + + /* + * If a device link was successfully created to a supplier, we + * now need to try and link the supplier to all its suppliers. + * + * This is needed to detect and delete false dependencies in + * fwnode links that haven't been converted to a device link + * yet. See comments in fw_devlink_create_devlink() for more + * details on the false dependency. + * + * Without deleting these false dependencies, some devices will + * never probe because they'll keep waiting for their false + * dependency fwnode links to be converted to device links. + */ + sup_dev = get_dev_from_fwnode(sup); + __fw_devlink_link_to_suppliers(sup_dev, sup_dev->fwnode); + put_device(sup_dev); } + + /* + * Make "proxy" SYNC_STATE_ONLY device links to represent the needs of + * all the descendants. This proxy link step is needed to handle the + * case where the supplier is added before the consumer's parent device + * (@dev). + */ + while ((child = fwnode_get_next_available_child_node(fwnode, child))) + __fw_devlink_link_to_suppliers(dev, child); +} + +static void fw_devlink_link_device(struct device *dev) +{ + struct fwnode_handle *fwnode = dev->fwnode; + + if (!fw_devlink_flags) + return; + + fw_devlink_parse_fwtree(fwnode); + + mutex_lock(&fwnode_link_lock); + __fw_devlink_link_to_consumers(dev); + __fw_devlink_link_to_suppliers(dev, fwnode); + mutex_unlock(&fwnode_link_lock); } /* Device links support end. */ @@ -2431,7 +2583,6 @@ void device_initialize(struct device *dev) #endif INIT_LIST_HEAD(&dev->links.consumers); INIT_LIST_HEAD(&dev->links.suppliers); - INIT_LIST_HEAD(&dev->links.needs_suppliers); INIT_LIST_HEAD(&dev->links.defer_sync); dev->links.status = DL_DEV_NO_DRIVER; } diff --git a/include/linux/device.h b/include/linux/device.h index 1e771ea4dca6..89bb8b84173e 100644 --- a/include/linux/device.h +++ b/include/linux/device.h @@ -351,18 +351,13 @@ enum dl_dev_state { * struct dev_links_info - Device data related to device links. * @suppliers: List of links to supplier devices. * @consumers: List of links to consumer devices. - * @needs_suppliers: Hook to global list of devices waiting for suppliers. * @defer_sync: Hook to global list of devices that have deferred sync_state. - * @need_for_probe: If needs_suppliers is on a list, this indicates if the - * suppliers are needed for probe or not. * @status: Driver status information. */ struct dev_links_info { struct list_head suppliers; struct list_head consumers; - struct list_head needs_suppliers; struct list_head defer_sync; - bool need_for_probe; enum dl_dev_state status; }; -- cgit v1.2.3-71-gd317 From 2d09e6eb4a6f20273959f4905ccf009da8c64c7a Mon Sep 17 00:00:00 2001 From: Saravana Kannan Date: Fri, 20 Nov 2020 18:02:32 -0800 Subject: driver core: Delete pointless parameter in fwnode_operations.add_links The struct device input to add_links() is not used for anything. So delete it. Acked-by: Rob Herring Signed-off-by: Saravana Kannan Link: https://lore.kernel.org/r/20201121020232.908850-18-saravanak@google.com Signed-off-by: Greg Kroah-Hartman --- drivers/base/core.c | 2 +- drivers/firmware/efi/efi-init.c | 3 +-- drivers/of/property.c | 3 +-- include/linux/fwnode.h | 3 +-- 4 files changed, 4 insertions(+), 7 deletions(-) (limited to 'include/linux') diff --git a/drivers/base/core.c b/drivers/base/core.c index 9edf9084fc98..63edb8bd9d7d 100644 --- a/drivers/base/core.c +++ b/drivers/base/core.c @@ -1472,7 +1472,7 @@ static void fw_devlink_parse_fwnode(struct fwnode_handle *fwnode) if (fwnode->flags & FWNODE_FLAG_LINKS_ADDED) return; - fwnode_call_int_op(fwnode, add_links, NULL); + fwnode_call_int_op(fwnode, add_links); fwnode->flags |= FWNODE_FLAG_LINKS_ADDED; } diff --git a/drivers/firmware/efi/efi-init.c b/drivers/firmware/efi/efi-init.c index c0c3d4c3837a..a552a08a1741 100644 --- a/drivers/firmware/efi/efi-init.c +++ b/drivers/firmware/efi/efi-init.c @@ -316,8 +316,7 @@ static struct device_node *find_pci_overlap_node(void) * resource reservation conflict on the memory window that the efifb * framebuffer steals from the PCIe host bridge. */ -static int efifb_add_links(struct fwnode_handle *fwnode, - struct device *dev) +static int efifb_add_links(struct fwnode_handle *fwnode) { struct device_node *sup_np; diff --git a/drivers/of/property.c b/drivers/of/property.c index 620d29fdace8..5f9eed79a8aa 100644 --- a/drivers/of/property.c +++ b/drivers/of/property.c @@ -1343,8 +1343,7 @@ static int of_link_property(struct device_node *con_np, const char *prop_name) return ret; } -static int of_fwnode_add_links(struct fwnode_handle *fwnode, - struct device *dev) +static int of_fwnode_add_links(struct fwnode_handle *fwnode) { struct property *p; struct device_node *con_np = to_of_node(fwnode); diff --git a/include/linux/fwnode.h b/include/linux/fwnode.h index ffa9129182a6..fde4ad97564c 100644 --- a/include/linux/fwnode.h +++ b/include/linux/fwnode.h @@ -127,8 +127,7 @@ struct fwnode_operations { (*graph_get_port_parent)(struct fwnode_handle *fwnode); int (*graph_parse_endpoint)(const struct fwnode_handle *fwnode, struct fwnode_endpoint *endpoint); - int (*add_links)(struct fwnode_handle *fwnode, - struct device *dev); + int (*add_links)(struct fwnode_handle *fwnode); }; #define fwnode_has_op(fwnode, op) \ -- cgit v1.2.3-71-gd317 From 0aec2da436623abe19b80b21dd9fc5ec9300a152 Mon Sep 17 00:00:00 2001 From: Andy Shevchenko Date: Wed, 9 Dec 2020 22:36:38 +0200 Subject: driver core: platform: Introduce platform_get_mem_or_io() There are at least few existing users of the proposed API which retrieves either MEM or IO resource from platform device. Make it common to utilize in the existing and new users. Cc: Eric Auger Cc: Alex Williamson Cc: kvm@vger.kernel.org Cc: linux-usb@vger.kernel.org Cc: Peng Hao Cc: Arnd Bergmann Reviewed-by: Cornelia Huck Signed-off-by: Andy Shevchenko Link: https://lore.kernel.org/r/20201209203642.27648-1-andriy.shevchenko@linux.intel.com Signed-off-by: Greg Kroah-Hartman --- drivers/base/platform.c | 15 +++++++++++++++ include/linux/platform_device.h | 3 +++ 2 files changed, 18 insertions(+) (limited to 'include/linux') diff --git a/drivers/base/platform.c b/drivers/base/platform.c index 8ad06daa2eaa..0358dc3ea3ad 100644 --- a/drivers/base/platform.c +++ b/drivers/base/platform.c @@ -63,6 +63,21 @@ struct resource *platform_get_resource(struct platform_device *dev, } EXPORT_SYMBOL_GPL(platform_get_resource); +struct resource *platform_get_mem_or_io(struct platform_device *dev, + unsigned int num) +{ + u32 i; + + for (i = 0; i < dev->num_resources; i++) { + struct resource *r = &dev->resource[i]; + + if ((resource_type(r) & (IORESOURCE_MEM|IORESOURCE_IO)) && num-- == 0) + return r; + } + return NULL; +} +EXPORT_SYMBOL_GPL(platform_get_mem_or_io); + #ifdef CONFIG_HAS_IOMEM /** * devm_platform_get_and_ioremap_resource - call devm_ioremap_resource() for a diff --git a/include/linux/platform_device.h b/include/linux/platform_device.h index 77a2aada106d..ee6a9f10c2c7 100644 --- a/include/linux/platform_device.h +++ b/include/linux/platform_device.h @@ -52,6 +52,9 @@ extern struct device platform_bus; extern struct resource *platform_get_resource(struct platform_device *, unsigned int, unsigned int); +extern struct resource *platform_get_mem_or_io(struct platform_device *, + unsigned int); + extern struct device * platform_find_device_by_driver(struct device *start, const struct device_driver *drv); -- cgit v1.2.3-71-gd317 From 2ab695aa8eb8f3226f68a2b91fc6103b56fcb57d Mon Sep 17 00:00:00 2001 From: Saravana Kannan Date: Fri, 11 Dec 2020 12:26:29 -0800 Subject: ACPI: Use fwnode_init() to set up fwnode Commit 01bb86b380a3 ("driver core: Add fwnode_init()") was supposed to fix up all instances of fwnode creation to use fwnode_init(). But looks like this instance was missed. This causes a NULL pointer dereference during device_add() [1]. So, fix it. [ 60.792324][ T1] Call trace: [ 60.795495][ T1] device_add+0xf60/0x16b0 __fw_devlink_link_to_consumers at drivers/base/core.c:1583 (inlined by) fw_devlink_link_device at drivers/base/core.c:1726 (inlined by) device_add at drivers/base/core.c:3088 [ 60.799813][ T1] platform_device_add+0x274/0x628 [ 60.804833][ T1] acpi_iort_init+0x9d8/0xc50 [ 60.809415][ T1] acpi_init+0x45c/0x4e8 [ 60.813556][ T1] do_one_initcall+0x170/0xb70 [ 60.818224][ T1] kernel_init_freeable+0x6a8/0x734 [ 60.823332][ T1] kernel_init+0x18/0x12c [ 60.827566][ T1] ret_from_fork+0x10/0x1c [ 60.838756][ T1] ---[ end trace fa5c8ce17a226d83 ]--- [1] - https://lore.kernel.org/linux-arm-kernel/02e7047071f0b54b046ac472adeeb3fafabc643c.camel@redhat.com/ Fixes: 01bb86b380a3 ("driver core: Add fwnode_init()") Reported-by: Qian Cai Suggested-by: Robin Murphy Tested-by: Marc Zyngier Acked-by: Rafael J. Wysocki Signed-off-by: Saravana Kannan Link: https://lore.kernel.org/r/20201211202629.2164655-1-saravanak@google.com Signed-off-by: Greg Kroah-Hartman --- include/linux/acpi.h | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) (limited to 'include/linux') diff --git a/include/linux/acpi.h b/include/linux/acpi.h index 39263c6b52e1..2630c2e953f7 100644 --- a/include/linux/acpi.h +++ b/include/linux/acpi.h @@ -55,7 +55,7 @@ static inline struct fwnode_handle *acpi_alloc_fwnode_static(void) if (!fwnode) return NULL; - fwnode->ops = &acpi_static_fwnode_ops; + fwnode_init(fwnode, &acpi_static_fwnode_ops); return fwnode; } -- cgit v1.2.3-71-gd317