From 6e331888643887ce85657527bc03f97d46235e71 Mon Sep 17 00:00:00 2001 From: Daniel Golle Date: Tue, 19 Dec 2023 02:33:14 +0000 Subject: [PATCH 4/8] mtd: ubi: attach from device tree Introduce device tree compatible 'linux,ubi' and attach compatible MTD devices using the MTD add notifier. This is needed for a UBI device to be available early at boot (and not only after late_initcall), so volumes on them can be used eg. as NVMEM providers for other drivers. Signed-off-by: Daniel Golle Signed-off-by: Richard Weinberger --- drivers/mtd/ubi/build.c | 135 ++++++++++++++++++++++++++++------------ 1 file changed, 96 insertions(+), 39 deletions(-) --- a/drivers/mtd/ubi/build.c +++ b/drivers/mtd/ubi/build.c @@ -27,6 +27,7 @@ #include #include #include +#include #include #include #include "ubi.h" @@ -1214,43 +1215,43 @@ static struct mtd_info * __init open_mtd return mtd; } -static int __init ubi_init(void) +static void ubi_notify_add(struct mtd_info *mtd) { - int err, i, k; + struct device_node *np = mtd_get_of_node(mtd); + int err; - /* Ensure that EC and VID headers have correct size */ - BUILD_BUG_ON(sizeof(struct ubi_ec_hdr) != 64); - BUILD_BUG_ON(sizeof(struct ubi_vid_hdr) != 64); + if (!of_device_is_compatible(np, "linux,ubi")) + return; - if (mtd_devs > UBI_MAX_DEVICES) { - pr_err("UBI error: too many MTD devices, maximum is %d\n", - UBI_MAX_DEVICES); - return -EINVAL; - } + /* + * we are already holding &mtd_table_mutex, but still need + * to bump refcount + */ + err = __get_mtd_device(mtd); + if (err) + return; - /* Create base sysfs directory and sysfs files */ - err = class_register(&ubi_class); + /* called while holding mtd_table_mutex */ + mutex_lock_nested(&ubi_devices_mutex, SINGLE_DEPTH_NESTING); + err = ubi_attach_mtd_dev(mtd, UBI_DEV_NUM_AUTO, 0, 0, false); + mutex_unlock(&ubi_devices_mutex); if (err < 0) - return err; - - err = misc_register(&ubi_ctrl_cdev); - if (err) { - pr_err("UBI error: cannot register device\n"); - goto out; - } + __put_mtd_device(mtd); +} - ubi_wl_entry_slab = kmem_cache_create("ubi_wl_entry_slab", - sizeof(struct ubi_wl_entry), - 0, 0, NULL); - if (!ubi_wl_entry_slab) { - err = -ENOMEM; - goto out_dev_unreg; - } +static void ubi_notify_remove(struct mtd_info *mtd) +{ + /* do nothing for now */ +} - err = ubi_debugfs_init(); - if (err) - goto out_slab; +static struct mtd_notifier ubi_mtd_notifier = { + .add = ubi_notify_add, + .remove = ubi_notify_remove, +}; +static int __init ubi_init_attach(void) +{ + int err, i, k; /* Attach MTD devices */ for (i = 0; i < mtd_devs; i++) { @@ -1298,25 +1299,79 @@ static int __init ubi_init(void) } } + return 0; + +out_detach: + for (k = 0; k < i; k++) + if (ubi_devices[k]) { + mutex_lock(&ubi_devices_mutex); + ubi_detach_mtd_dev(ubi_devices[k]->ubi_num, 1); + mutex_unlock(&ubi_devices_mutex); + } + return err; +} +#ifndef CONFIG_MTD_UBI_MODULE +late_initcall(ubi_init_attach); +#endif + +static int __init ubi_init(void) +{ + int err; + + /* Ensure that EC and VID headers have correct size */ + BUILD_BUG_ON(sizeof(struct ubi_ec_hdr) != 64); + BUILD_BUG_ON(sizeof(struct ubi_vid_hdr) != 64); + + if (mtd_devs > UBI_MAX_DEVICES) { + pr_err("UBI error: too many MTD devices, maximum is %d\n", + UBI_MAX_DEVICES); + return -EINVAL; + } + + /* Create base sysfs directory and sysfs files */ + err = class_register(&ubi_class); + if (err < 0) + return err; + + err = misc_register(&ubi_ctrl_cdev); + if (err) { + pr_err("UBI error: cannot register device\n"); + goto out; + } + + ubi_wl_entry_slab = kmem_cache_create("ubi_wl_entry_slab", + sizeof(struct ubi_wl_entry), + 0, 0, NULL); + if (!ubi_wl_entry_slab) { + err = -ENOMEM; + goto out_dev_unreg; + } + + err = ubi_debugfs_init(); + if (err) + goto out_slab; + err = ubiblock_init(); if (err) { pr_err("UBI error: block: cannot initialize, error %d\n", err); /* See comment above re-ubi_is_module(). */ if (ubi_is_module()) - goto out_detach; + goto out_slab; + } + + register_mtd_user(&ubi_mtd_notifier); + + if (ubi_is_module()) { + err = ubi_init_attach(); + if (err) + goto out_mtd_notifier; } return 0; -out_detach: - for (k = 0; k < i; k++) - if (ubi_devices[k]) { - mutex_lock(&ubi_devices_mutex); - ubi_detach_mtd_dev(ubi_devices[k]->ubi_num, 1); - mutex_unlock(&ubi_devices_mutex); - } - ubi_debugfs_exit(); +out_mtd_notifier: + unregister_mtd_user(&ubi_mtd_notifier); out_slab: kmem_cache_destroy(ubi_wl_entry_slab); out_dev_unreg: @@ -1326,13 +1381,15 @@ out: pr_err("UBI error: cannot initialize UBI, error %d\n", err); return err; } -late_initcall(ubi_init); +device_initcall(ubi_init); + static void __exit ubi_exit(void) { int i; ubiblock_exit(); + unregister_mtd_user(&ubi_mtd_notifier); for (i = 0; i < UBI_MAX_DEVICES; i++) if (ubi_devices[i]) {