From patchwork Sun Dec 17 00:09:30 2023 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Daniel Golle X-Patchwork-Id: 755707 Received: from pidgin.makrotopia.org (pidgin.makrotopia.org [185.142.180.65]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by smtp.subspace.kernel.org (Postfix) with ESMTPS id DDD83A35; Sun, 17 Dec 2023 00:09:52 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; dmarc=none (p=none dis=none) header.from=makrotopia.org Authentication-Results: smtp.subspace.kernel.org; spf=pass smtp.mailfrom=makrotopia.org Received: from local by pidgin.makrotopia.org with esmtpsa (TLS1.3:TLS_AES_256_GCM_SHA384:256) (Exim 4.96.2) (envelope-from ) id 1rEeiq-00064i-1T; Sun, 17 Dec 2023 00:09:33 +0000 Date: Sun, 17 Dec 2023 00:09:30 +0000 From: Daniel Golle To: Miquel Raynal , Richard Weinberger , Vignesh Raghavendra , Rob Herring , Krzysztof Kozlowski , Conor Dooley , Daniel Golle , =?utf-8?b?UmFmYcWCIE1pxYJlY2tp?= , linux-mtd@lists.infradead.org, devicetree@vger.kernel.org, linux-kernel@vger.kernel.org Subject: [PATCH v5 1/7] dt-bindings: mtd: add basic bindings for UBI Message-ID: References: Precedence: bulk X-Mailing-List: devicetree@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Content-Disposition: inline In-Reply-To: Add basic bindings for UBI devices and volumes. Signed-off-by: Daniel Golle Reviewed-by: Rob Herring --- .../bindings/mtd/partitions/linux,ubi.yaml | 65 +++++++++++++++++++ .../bindings/mtd/partitions/ubi-volume.yaml | 35 ++++++++++ 2 files changed, 100 insertions(+) create mode 100644 Documentation/devicetree/bindings/mtd/partitions/linux,ubi.yaml create mode 100644 Documentation/devicetree/bindings/mtd/partitions/ubi-volume.yaml diff --git a/Documentation/devicetree/bindings/mtd/partitions/linux,ubi.yaml b/Documentation/devicetree/bindings/mtd/partitions/linux,ubi.yaml new file mode 100644 index 0000000000000..7084a1945b310 --- /dev/null +++ b/Documentation/devicetree/bindings/mtd/partitions/linux,ubi.yaml @@ -0,0 +1,65 @@ +# SPDX-License-Identifier: GPL-2.0-only OR BSD-2-Clause +%YAML 1.2 +--- +$id: http://devicetree.org/schemas/mtd/partitions/linux,ubi.yaml# +$schema: http://devicetree.org/meta-schemas/core.yaml# + +title: Unsorted Block Images + +description: | + UBI ("Unsorted Block Images") is a volume management system for raw + flash devices which manages multiple logical volumes on a single + physical flash device and spreads the I/O load (i.e wear-leveling) + across the whole flash chip. + +maintainers: + - Daniel Golle + +allOf: + - $ref: partition.yaml# + +properties: + compatible: + const: linux,ubi + + volumes: + type: object + description: UBI Volumes + + patternProperties: + "^ubi-volume-.*$": + $ref: /schemas/mtd/partitions/ubi-volume.yaml# + + unevaluatedProperties: false + +required: + - compatible + +unevaluatedProperties: false + +examples: + - | + partitions { + compatible = "fixed-partitions"; + #address-cells = <1>; + #size-cells = <1>; + + partition@0 { + reg = <0x0 0x100000>; + label = "bootloader"; + read-only; + }; + + partition@100000 { + reg = <0x100000 0x1ff00000>; + label = "ubi"; + compatible = "linux,ubi"; + + volumes { + ubi-volume-caldata { + volid = <2>; + volname = "rf"; + }; + }; + }; + }; diff --git a/Documentation/devicetree/bindings/mtd/partitions/ubi-volume.yaml b/Documentation/devicetree/bindings/mtd/partitions/ubi-volume.yaml new file mode 100644 index 0000000000000..c17d0caf07d97 --- /dev/null +++ b/Documentation/devicetree/bindings/mtd/partitions/ubi-volume.yaml @@ -0,0 +1,35 @@ +# SPDX-License-Identifier: GPL-2.0-only OR BSD-2-Clause +%YAML 1.2 +--- +$id: http://devicetree.org/schemas/mtd/partitions/ubi-volume.yaml# +$schema: http://devicetree.org/meta-schemas/core.yaml# + +title: UBI volume + +description: | + This binding describes a single UBI volume. Volumes can be matches either + by their ID or their name, or both. + +maintainers: + - Daniel Golle + +properties: + volid: + $ref: "/schemas/types.yaml#/definitions/uint32" + description: + Match UBI volume ID + + volname: + $ref: "/schemas/types.yaml#/definitions/string" + description: + Match UBI volume ID + +anyOf: + - required: + - volid + + - required: + - volname + +# This is a generic file other binding inherit from and extend +additionalProperties: true From patchwork Sun Dec 17 00:09:41 2023 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Daniel Golle X-Patchwork-Id: 755197 Received: from pidgin.makrotopia.org (pidgin.makrotopia.org [185.142.180.65]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by smtp.subspace.kernel.org (Postfix) with ESMTPS id 6DA841102; Sun, 17 Dec 2023 00:09:53 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; dmarc=none (p=none dis=none) header.from=makrotopia.org Authentication-Results: smtp.subspace.kernel.org; spf=pass smtp.mailfrom=makrotopia.org Received: from local by pidgin.makrotopia.org with esmtpsa (TLS1.3:TLS_AES_256_GCM_SHA384:256) (Exim 4.96.2) (envelope-from ) id 1rEej0-000651-2a; Sun, 17 Dec 2023 00:09:44 +0000 Date: Sun, 17 Dec 2023 00:09:41 +0000 From: Daniel Golle To: Miquel Raynal , Richard Weinberger , Vignesh Raghavendra , Rob Herring , Krzysztof Kozlowski , Conor Dooley , Daniel Golle , =?utf-8?b?UmFmYcWCIE1pxYJlY2tp?= , linux-mtd@lists.infradead.org, devicetree@vger.kernel.org, linux-kernel@vger.kernel.org Subject: [PATCH v5 2/7] dt-bindings: mtd: ubi-volume: allow UBI volumes to provide NVMEM Message-ID: References: Precedence: bulk X-Mailing-List: devicetree@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Content-Disposition: inline In-Reply-To: UBI volumes may be used to contain NVMEM bits, typically device MAC addresses or wireless radio calibration data. Signed-off-by: Daniel Golle Reviewed-by: Rob Herring --- .../devicetree/bindings/mtd/partitions/linux,ubi.yaml | 10 ++++++++++ .../devicetree/bindings/mtd/partitions/ubi-volume.yaml | 5 +++++ 2 files changed, 15 insertions(+) diff --git a/Documentation/devicetree/bindings/mtd/partitions/linux,ubi.yaml b/Documentation/devicetree/bindings/mtd/partitions/linux,ubi.yaml index 7084a1945b310..27e1ac1f252e4 100644 --- a/Documentation/devicetree/bindings/mtd/partitions/linux,ubi.yaml +++ b/Documentation/devicetree/bindings/mtd/partitions/linux,ubi.yaml @@ -59,6 +59,16 @@ examples: ubi-volume-caldata { volid = <2>; volname = "rf"; + + nvmem-layout { + compatible = "fixed-layout"; + #address-cells = <1>; + #size-cells = <1>; + + eeprom@0 { + reg = <0x0 0x1000>; + }; + }; }; }; }; diff --git a/Documentation/devicetree/bindings/mtd/partitions/ubi-volume.yaml b/Documentation/devicetree/bindings/mtd/partitions/ubi-volume.yaml index c17d0caf07d97..098da3af13a26 100644 --- a/Documentation/devicetree/bindings/mtd/partitions/ubi-volume.yaml +++ b/Documentation/devicetree/bindings/mtd/partitions/ubi-volume.yaml @@ -24,6 +24,11 @@ properties: description: Match UBI volume ID + nvmem-layout: + $ref: /schemas/nvmem/layouts/nvmem-layout.yaml# + description: + This container may reference an NVMEM layout parser. + anyOf: - required: - volid From patchwork Sun Dec 17 00:09:51 2023 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Daniel Golle X-Patchwork-Id: 755706 Received: from pidgin.makrotopia.org (pidgin.makrotopia.org [185.142.180.65]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by smtp.subspace.kernel.org (Postfix) with ESMTPS id 47CF636E; Sun, 17 Dec 2023 00:10:04 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; dmarc=none (p=none dis=none) header.from=makrotopia.org Authentication-Results: smtp.subspace.kernel.org; spf=pass smtp.mailfrom=makrotopia.org Received: from local by pidgin.makrotopia.org with esmtpsa (TLS1.3:TLS_AES_256_GCM_SHA384:256) (Exim 4.96.2) (envelope-from ) id 1rEejA-00065M-2W; Sun, 17 Dec 2023 00:09:53 +0000 Date: Sun, 17 Dec 2023 00:09:51 +0000 From: Daniel Golle To: Miquel Raynal , Richard Weinberger , Vignesh Raghavendra , Rob Herring , Krzysztof Kozlowski , Conor Dooley , Daniel Golle , =?utf-8?b?UmFmYcWCIE1pxYJlY2tp?= , linux-mtd@lists.infradead.org, devicetree@vger.kernel.org, linux-kernel@vger.kernel.org Subject: [PATCH v5 3/7] mtd: ubi: block: use notifier to create ubiblock from parameter Message-ID: <964a9482696b5c458eba90d3ed44154c9112828f.1702770711.git.daniel@makrotopia.org> References: Precedence: bulk X-Mailing-List: devicetree@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Content-Disposition: inline In-Reply-To: Use UBI_VOLUME_ADDED notification to create ubiblock device specified on kernel cmdline or module parameter. This makes things more simple and has the advantage that ubiblock devices on volumes which are not present at the time the ubi module is probed will still be created. Suggested-by: Zhihao Cheng Signed-off-by: Daniel Golle --- drivers/mtd/ubi/block.c | 136 ++++++++++++++++++++-------------------- drivers/mtd/ubi/kapi.c | 54 +++++++++++----- drivers/mtd/ubi/ubi.h | 1 + 3 files changed, 106 insertions(+), 85 deletions(-) diff --git a/drivers/mtd/ubi/block.c b/drivers/mtd/ubi/block.c index 309a42aeaa4cd..a467df5aa130a 100644 --- a/drivers/mtd/ubi/block.c +++ b/drivers/mtd/ubi/block.c @@ -65,10 +65,10 @@ struct ubiblock_pdu { }; /* Numbers of elements set in the @ubiblock_param array */ -static int ubiblock_devs __initdata; +static int ubiblock_devs; /* MTD devices specification parameters */ -static struct ubiblock_param ubiblock_param[UBIBLOCK_MAX_DEVICES] __initdata; +static struct ubiblock_param ubiblock_param[UBIBLOCK_MAX_DEVICES]; struct ubiblock { struct ubi_volume_desc *desc; @@ -534,6 +534,70 @@ static int ubiblock_resize(struct ubi_volume_info *vi) return 0; } +static bool +match_volume_desc(struct ubi_volume_info *vi, const char *name, int ubi_num, int vol_id) +{ + int err, len, cur_ubi_num, cur_vol_id; + + if (ubi_num == -1) { + /* No ubi num, name must be a vol device path */ + err = ubi_get_num_by_path(name, &cur_ubi_num, &cur_vol_id); + if (err || vi->ubi_num != cur_ubi_num || vi->vol_id != cur_vol_id) + return false; + + return true; + } + + if (vol_id == -1) { + /* Got ubi_num, but no vol_id, name must be volume name */ + if (vi->ubi_num != ubi_num) + return false; + + len = strnlen(name, UBI_VOL_NAME_MAX + 1); + if (len < 1 || vi->name_len != len) + return false; + + if (strcmp(name, vi->name)) + return false; + + return true; + } + + if (vi->ubi_num != ubi_num) + return false; + + if (vi->vol_id != vol_id) + return false; + + return true; +} + +static void +ubiblock_create_from_param(struct ubi_volume_info *vi) +{ + int i, ret = 0; + struct ubiblock_param *p; + + /* + * Iterate over ubiblock cmdline parameters. If a parameter matches the + * newly added volume create the ubiblock device for it. + */ + for (i = 0; i < ubiblock_devs; i++) { + p = &ubiblock_param[i]; + + if (!match_volume_desc(vi, p->name, p->ubi_num, p->vol_id)) + continue; + + ret = ubiblock_create(vi); + if (ret) { + pr_err( + "UBI: block: can't add '%s' volume on ubi%d_%d, err=%d\n", + vi->name, p->ubi_num, p->vol_id, ret); + } + break; + } +} + static int ubiblock_notify(struct notifier_block *nb, unsigned long notification_type, void *ns_ptr) { @@ -541,10 +605,7 @@ static int ubiblock_notify(struct notifier_block *nb, switch (notification_type) { case UBI_VOLUME_ADDED: - /* - * We want to enforce explicit block device creation for - * volumes, so when a volume is added we do nothing. - */ + ubiblock_create_from_param(&nt->vi); break; case UBI_VOLUME_REMOVED: ubiblock_remove(&nt->vi); @@ -570,56 +631,6 @@ static struct notifier_block ubiblock_notifier = { .notifier_call = ubiblock_notify, }; -static struct ubi_volume_desc * __init -open_volume_desc(const char *name, int ubi_num, int vol_id) -{ - if (ubi_num == -1) - /* No ubi num, name must be a vol device path */ - return ubi_open_volume_path(name, UBI_READONLY); - else if (vol_id == -1) - /* No vol_id, must be vol_name */ - return ubi_open_volume_nm(ubi_num, name, UBI_READONLY); - else - return ubi_open_volume(ubi_num, vol_id, UBI_READONLY); -} - -static void __init ubiblock_create_from_param(void) -{ - int i, ret = 0; - struct ubiblock_param *p; - struct ubi_volume_desc *desc; - struct ubi_volume_info vi; - - /* - * If there is an error creating one of the ubiblocks, continue on to - * create the following ubiblocks. This helps in a circumstance where - * the kernel command-line specifies multiple block devices and some - * may be broken, but we still want the working ones to come up. - */ - for (i = 0; i < ubiblock_devs; i++) { - p = &ubiblock_param[i]; - - desc = open_volume_desc(p->name, p->ubi_num, p->vol_id); - if (IS_ERR(desc)) { - pr_err( - "UBI: block: can't open volume on ubi%d_%d, err=%ld\n", - p->ubi_num, p->vol_id, PTR_ERR(desc)); - continue; - } - - ubi_get_volume_info(desc, &vi); - ubi_close_volume(desc); - - ret = ubiblock_create(&vi); - if (ret) { - pr_err( - "UBI: block: can't add '%s' volume on ubi%d_%d, err=%d\n", - vi.name, p->ubi_num, p->vol_id, ret); - continue; - } - } -} - static void ubiblock_remove_all(void) { struct ubiblock *next; @@ -645,18 +656,7 @@ int __init ubiblock_init(void) if (ubiblock_major < 0) return ubiblock_major; - /* - * Attach block devices from 'block=' module param. - * Even if one block device in the param list fails to come up, - * still allow the module to load and leave any others up. - */ - ubiblock_create_from_param(); - - /* - * Block devices are only created upon user requests, so we ignore - * existing volumes. - */ - ret = ubi_register_volume_notifier(&ubiblock_notifier, 1); + ret = ubi_register_volume_notifier(&ubiblock_notifier, 0); if (ret) goto err_unreg; return 0; diff --git a/drivers/mtd/ubi/kapi.c b/drivers/mtd/ubi/kapi.c index 5db653eacbd45..fbf3a7fe2af79 100644 --- a/drivers/mtd/ubi/kapi.c +++ b/drivers/mtd/ubi/kapi.c @@ -279,6 +279,41 @@ struct ubi_volume_desc *ubi_open_volume_nm(int ubi_num, const char *name, } EXPORT_SYMBOL_GPL(ubi_open_volume_nm); +/** + * ubi_get_num_by_path - get UBI device and volume number from device path + * @pathname: volume character device node path + * @ubi_num: pointer to UBI device number to be set + * @vol_id: pointer to UBI volume ID to be set + * + * Returns 0 on success and sets ubi_num and vol_id, returns error otherwise. + */ +int ubi_get_num_by_path(const char *pathname, int *ubi_num, int *vol_id) +{ + int error; + struct path path; + struct kstat stat; + + error = kern_path(pathname, LOOKUP_FOLLOW, &path); + if (error) + return error; + + error = vfs_getattr(&path, &stat, STATX_TYPE, AT_STATX_SYNC_AS_STAT); + path_put(&path); + if (error) + return error; + + if (!S_ISCHR(stat.mode)) + return -EINVAL; + + *ubi_num = ubi_major2num(MAJOR(stat.rdev)); + *vol_id = MINOR(stat.rdev) - 1; + + if (*vol_id < 0 || *ubi_num < 0) + return -ENODEV; + + return 0; +} + /** * ubi_open_volume_path - open UBI volume by its character device node path. * @pathname: volume character device node path @@ -290,32 +325,17 @@ EXPORT_SYMBOL_GPL(ubi_open_volume_nm); struct ubi_volume_desc *ubi_open_volume_path(const char *pathname, int mode) { int error, ubi_num, vol_id; - struct path path; - struct kstat stat; dbg_gen("open volume %s, mode %d", pathname, mode); if (!pathname || !*pathname) return ERR_PTR(-EINVAL); - error = kern_path(pathname, LOOKUP_FOLLOW, &path); - if (error) - return ERR_PTR(error); - - error = vfs_getattr(&path, &stat, STATX_TYPE, AT_STATX_SYNC_AS_STAT); - path_put(&path); + error = ubi_get_num_by_path(pathname, &ubi_num, &vol_id); if (error) return ERR_PTR(error); - if (!S_ISCHR(stat.mode)) - return ERR_PTR(-EINVAL); - - ubi_num = ubi_major2num(MAJOR(stat.rdev)); - vol_id = MINOR(stat.rdev) - 1; - - if (vol_id >= 0 && ubi_num >= 0) - return ubi_open_volume(ubi_num, vol_id, mode); - return ERR_PTR(-ENODEV); + return ubi_open_volume(ubi_num, vol_id, mode); } EXPORT_SYMBOL_GPL(ubi_open_volume_path); diff --git a/drivers/mtd/ubi/ubi.h b/drivers/mtd/ubi/ubi.h index a5ec566df0d74..17b463804c979 100644 --- a/drivers/mtd/ubi/ubi.h +++ b/drivers/mtd/ubi/ubi.h @@ -962,6 +962,7 @@ void ubi_free_internal_volumes(struct ubi_device *ubi); void ubi_do_get_device_info(struct ubi_device *ubi, struct ubi_device_info *di); void ubi_do_get_volume_info(struct ubi_device *ubi, struct ubi_volume *vol, struct ubi_volume_info *vi); +int ubi_get_num_by_path(const char *pathname, int *ubi_num, int *vol_id); /* scan.c */ int ubi_compare_lebs(struct ubi_device *ubi, const struct ubi_ainf_peb *aeb, int pnum, const struct ubi_vid_hdr *vid_hdr); From patchwork Sun Dec 17 00:10:02 2023 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Daniel Golle X-Patchwork-Id: 755196 Received: from pidgin.makrotopia.org (pidgin.makrotopia.org [185.142.180.65]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by smtp.subspace.kernel.org (Postfix) with ESMTPS id 123D0A47; Sun, 17 Dec 2023 00:10:12 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; dmarc=none (p=none dis=none) header.from=makrotopia.org Authentication-Results: smtp.subspace.kernel.org; spf=pass smtp.mailfrom=makrotopia.org Received: from local by pidgin.makrotopia.org with esmtpsa (TLS1.3:TLS_AES_256_GCM_SHA384:256) (Exim 4.96.2) (envelope-from ) id 1rEejL-00065g-2D; Sun, 17 Dec 2023 00:10:04 +0000 Date: Sun, 17 Dec 2023 00:10:02 +0000 From: Daniel Golle To: Miquel Raynal , Richard Weinberger , Vignesh Raghavendra , Rob Herring , Krzysztof Kozlowski , Conor Dooley , Daniel Golle , =?utf-8?b?UmFmYcWCIE1pxYJlY2tp?= , linux-mtd@lists.infradead.org, devicetree@vger.kernel.org, linux-kernel@vger.kernel.org Subject: [PATCH v5 4/7] mtd: ubi: attach from device tree Message-ID: References: Precedence: bulk X-Mailing-List: devicetree@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Content-Disposition: inline In-Reply-To: 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 --- drivers/mtd/ubi/build.c | 135 ++++++++++++++++++++++++++++------------ 1 file changed, 96 insertions(+), 39 deletions(-) diff --git a/drivers/mtd/ubi/build.c b/drivers/mtd/ubi/build.c index 7d4ff1193db6f..8c3f763e4ddb8 100644 --- 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" @@ -1219,43 +1220,43 @@ static struct mtd_info * __init open_mtd_device(const char *mtd_dev) 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, 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++) { @@ -1304,25 +1305,79 @@ 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: @@ -1332,13 +1387,15 @@ static int __init ubi_init(void) 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]) { From patchwork Sun Dec 17 00:10:12 2023 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Daniel Golle X-Patchwork-Id: 755705 Received: from pidgin.makrotopia.org (pidgin.makrotopia.org [185.142.180.65]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by smtp.subspace.kernel.org (Postfix) with ESMTPS id EE3FAA32; Sun, 17 Dec 2023 00:10:23 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; dmarc=none (p=none dis=none) header.from=makrotopia.org Authentication-Results: smtp.subspace.kernel.org; spf=pass smtp.mailfrom=makrotopia.org Received: from local by pidgin.makrotopia.org with esmtpsa (TLS1.3:TLS_AES_256_GCM_SHA384:256) (Exim 4.96.2) (envelope-from ) id 1rEejW-000660-0r; Sun, 17 Dec 2023 00:10:15 +0000 Date: Sun, 17 Dec 2023 00:10:12 +0000 From: Daniel Golle To: Miquel Raynal , Richard Weinberger , Vignesh Raghavendra , Rob Herring , Krzysztof Kozlowski , Conor Dooley , Daniel Golle , =?utf-8?b?UmFmYcWCIE1pxYJlY2tp?= , linux-mtd@lists.infradead.org, devicetree@vger.kernel.org, linux-kernel@vger.kernel.org Subject: [PATCH v5 5/7] mtd: ubi: introduce pre-removal notification for UBI volumes Message-ID: References: Precedence: bulk X-Mailing-List: devicetree@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Content-Disposition: inline In-Reply-To: Introduce a new notification type UBI_VOLUME_SHUTDOWN to inform users that a volume is just about to be removed. This is needed because users (such as the NVMEM subsystem) expect that at the time their removal function is called, the parenting device is still available (for removal of sysfs nodes, for example, in case of NVMEM which otherwise WARNs on volume removal). Signed-off-by: Daniel Golle --- drivers/mtd/ubi/build.c | 19 ++++++++++++++----- drivers/mtd/ubi/kapi.c | 2 +- drivers/mtd/ubi/ubi.h | 2 ++ drivers/mtd/ubi/vmt.c | 17 +++++++++++++++-- include/linux/mtd/ubi.h | 2 ++ 5 files changed, 34 insertions(+), 8 deletions(-) diff --git a/drivers/mtd/ubi/build.c b/drivers/mtd/ubi/build.c index 8c3f763e4ddb8..a7e3a6246c0e9 100644 --- a/drivers/mtd/ubi/build.c +++ b/drivers/mtd/ubi/build.c @@ -93,7 +93,7 @@ static struct ubi_device *ubi_devices[UBI_MAX_DEVICES]; /* Serializes UBI devices creations and removals */ DEFINE_MUTEX(ubi_devices_mutex); -/* Protects @ubi_devices and @ubi->ref_count */ +/* Protects @ubi_devices, @ubi->ref_count and @ubi->is_dead */ static DEFINE_SPINLOCK(ubi_devices_lock); /* "Show" method for files in '//class/ubi/' */ @@ -261,6 +261,9 @@ struct ubi_device *ubi_get_device(int ubi_num) spin_lock(&ubi_devices_lock); ubi = ubi_devices[ubi_num]; + if (ubi && ubi->is_dead) + ubi = NULL; + if (ubi) { ubi_assert(ubi->ref_count >= 0); ubi->ref_count += 1; @@ -298,7 +301,7 @@ struct ubi_device *ubi_get_by_major(int major) spin_lock(&ubi_devices_lock); for (i = 0; i < UBI_MAX_DEVICES; i++) { ubi = ubi_devices[i]; - if (ubi && MAJOR(ubi->cdev.dev) == major) { + if (ubi && !ubi->is_dead && MAJOR(ubi->cdev.dev) == major) { ubi_assert(ubi->ref_count >= 0); ubi->ref_count += 1; get_device(&ubi->dev); @@ -327,7 +330,7 @@ int ubi_major2num(int major) for (i = 0; i < UBI_MAX_DEVICES; i++) { struct ubi_device *ubi = ubi_devices[i]; - if (ubi && MAJOR(ubi->cdev.dev) == major) { + if (ubi && !ubi->is_dead && MAJOR(ubi->cdev.dev) == major) { ubi_num = ubi->ubi_num; break; } @@ -514,7 +517,7 @@ static void ubi_free_volumes_from(struct ubi_device *ubi, int from) int i; for (i = from; i < ubi->vtbl_slots + UBI_INT_VOL_COUNT; i++) { - if (!ubi->volumes[i]) + if (!ubi->volumes[i] || ubi->volumes[i]->is_dead) continue; ubi_eba_replace_table(ubi->volumes[i], NULL); ubi_fastmap_destroy_checkmap(ubi->volumes[i]); @@ -1099,7 +1102,6 @@ int ubi_detach_mtd_dev(int ubi_num, int anyway) return -EINVAL; spin_lock(&ubi_devices_lock); - put_device(&ubi->dev); ubi->ref_count -= 1; if (ubi->ref_count) { if (!anyway) { @@ -1110,6 +1112,13 @@ int ubi_detach_mtd_dev(int ubi_num, int anyway) ubi_err(ubi, "%s reference count %d, destroy anyway", ubi->ubi_name, ubi->ref_count); } + ubi->is_dead = true; + spin_unlock(&ubi_devices_lock); + + ubi_notify_all(ubi, UBI_VOLUME_SHUTDOWN, NULL); + + spin_lock(&ubi_devices_lock); + put_device(&ubi->dev); ubi_devices[ubi_num] = NULL; spin_unlock(&ubi_devices_lock); diff --git a/drivers/mtd/ubi/kapi.c b/drivers/mtd/ubi/kapi.c index fbf3a7fe2af79..f1ea8677467fb 100644 --- a/drivers/mtd/ubi/kapi.c +++ b/drivers/mtd/ubi/kapi.c @@ -152,7 +152,7 @@ struct ubi_volume_desc *ubi_open_volume(int ubi_num, int vol_id, int mode) spin_lock(&ubi->volumes_lock); vol = ubi->volumes[vol_id]; - if (!vol) + if (!vol || vol->is_dead) goto out_unlock; err = -EBUSY; diff --git a/drivers/mtd/ubi/ubi.h b/drivers/mtd/ubi/ubi.h index 17b463804c979..56a74a3e2d9ab 100644 --- a/drivers/mtd/ubi/ubi.h +++ b/drivers/mtd/ubi/ubi.h @@ -348,6 +348,7 @@ struct ubi_volume { int writers; int exclusive; int metaonly; + bool is_dead; int reserved_pebs; int vol_type; @@ -568,6 +569,7 @@ struct ubi_device { spinlock_t volumes_lock; int ref_count; int image_seq; + bool is_dead; int rsvd_pebs; int avail_pebs; diff --git a/drivers/mtd/ubi/vmt.c b/drivers/mtd/ubi/vmt.c index 2c867d16f89f7..ee80c04d1d5d0 100644 --- a/drivers/mtd/ubi/vmt.c +++ b/drivers/mtd/ubi/vmt.c @@ -59,7 +59,7 @@ static ssize_t vol_attribute_show(struct device *dev, struct ubi_device *ubi = vol->ubi; spin_lock(&ubi->volumes_lock); - if (!ubi->volumes[vol->vol_id]) { + if (!ubi->volumes[vol->vol_id] || ubi->volumes[vol->vol_id]->is_dead) { spin_unlock(&ubi->volumes_lock); return -ENODEV; } @@ -189,7 +189,7 @@ int ubi_create_volume(struct ubi_device *ubi, struct ubi_mkvol_req *req) /* Ensure that the name is unique */ for (i = 0; i < ubi->vtbl_slots; i++) - if (ubi->volumes[i] && + if (ubi->volumes[i] && !ubi->volumes[i]->is_dead && ubi->volumes[i]->name_len == req->name_len && !strcmp(ubi->volumes[i]->name, req->name)) { ubi_err(ubi, "volume \"%s\" exists (ID %d)", @@ -352,6 +352,19 @@ int ubi_remove_volume(struct ubi_volume_desc *desc, int no_vtbl) err = -EBUSY; goto out_unlock; } + + /* + * Mark volume as dead at this point to prevent that anyone + * can take a reference to the volume from now on. + * This is necessary as we have to release the spinlock before + * calling ubi_volume_notify. + */ + vol->is_dead = true; + spin_unlock(&ubi->volumes_lock); + + ubi_volume_notify(ubi, vol, UBI_VOLUME_SHUTDOWN); + + spin_lock(&ubi->volumes_lock); ubi->volumes[vol_id] = NULL; spin_unlock(&ubi->volumes_lock); diff --git a/include/linux/mtd/ubi.h b/include/linux/mtd/ubi.h index a529347fd75b2..562f92504f2b7 100644 --- a/include/linux/mtd/ubi.h +++ b/include/linux/mtd/ubi.h @@ -192,6 +192,7 @@ struct ubi_device_info { * or a volume was removed) * @UBI_VOLUME_RESIZED: a volume has been re-sized * @UBI_VOLUME_RENAMED: a volume has been re-named + * @UBI_VOLUME_SHUTDOWN: a volume is going to be removed, shutdown users * @UBI_VOLUME_UPDATED: data has been written to a volume * * These constants define which type of event has happened when a volume @@ -202,6 +203,7 @@ enum { UBI_VOLUME_REMOVED, UBI_VOLUME_RESIZED, UBI_VOLUME_RENAMED, + UBI_VOLUME_SHUTDOWN, UBI_VOLUME_UPDATED, }; From patchwork Sun Dec 17 00:10:21 2023 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Daniel Golle X-Patchwork-Id: 755195 Received: from pidgin.makrotopia.org (pidgin.makrotopia.org [185.142.180.65]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by smtp.subspace.kernel.org (Postfix) with ESMTPS id 15C8F4432; Sun, 17 Dec 2023 00:10:33 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; dmarc=none (p=none dis=none) header.from=makrotopia.org Authentication-Results: smtp.subspace.kernel.org; spf=pass smtp.mailfrom=makrotopia.org Received: from local by pidgin.makrotopia.org with esmtpsa (TLS1.3:TLS_AES_256_GCM_SHA384:256) (Exim 4.96.2) (envelope-from ) id 1rEejf-00066Q-1y; Sun, 17 Dec 2023 00:10:24 +0000 Date: Sun, 17 Dec 2023 00:10:21 +0000 From: Daniel Golle To: Miquel Raynal , Richard Weinberger , Vignesh Raghavendra , Rob Herring , Krzysztof Kozlowski , Conor Dooley , Daniel Golle , =?utf-8?b?UmFmYcWCIE1pxYJlY2tp?= , linux-mtd@lists.infradead.org, devicetree@vger.kernel.org, linux-kernel@vger.kernel.org Subject: [PATCH v5 6/7] mtd: ubi: populate ubi volume fwnode Message-ID: References: Precedence: bulk X-Mailing-List: devicetree@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Content-Disposition: inline In-Reply-To: Look for the 'volumes' subnode of an MTD partition attached to a UBI device and attach matching child nodes to UBI volumes. This allows UBI volumes to be referenced in device tree, e.g. for use as NVMEM providers. Signed-off-by: Daniel Golle --- drivers/mtd/ubi/vmt.c | 27 +++++++++++++++++++++++++++ 1 file changed, 27 insertions(+) diff --git a/drivers/mtd/ubi/vmt.c b/drivers/mtd/ubi/vmt.c index ee80c04d1d5d0..7824ff069bd62 100644 --- a/drivers/mtd/ubi/vmt.c +++ b/drivers/mtd/ubi/vmt.c @@ -124,6 +124,31 @@ static void vol_release(struct device *dev) kfree(vol); } +static struct fwnode_handle *find_volume_fwnode(struct ubi_volume *vol) +{ + struct fwnode_handle *fw_vols, *fw_vol; + const char *volname; + u32 volid; + + fw_vols = device_get_named_child_node(vol->dev.parent->parent, "volumes"); + if (!fw_vols) + return NULL; + + fwnode_for_each_child_node(fw_vols, fw_vol) { + if (!fwnode_property_read_string(fw_vol, "volname", &volname) && + strncmp(volname, vol->name, vol->name_len)) + continue; + + if (!fwnode_property_read_u32(fw_vol, "volid", &volid) && + vol->vol_id != volid) + continue; + + return fw_vol; + } + + return NULL; +} + /** * ubi_create_volume - create volume. * @ubi: UBI device description object @@ -223,6 +248,7 @@ int ubi_create_volume(struct ubi_device *ubi, struct ubi_mkvol_req *req) vol->name_len = req->name_len; memcpy(vol->name, req->name, vol->name_len); vol->ubi = ubi; + device_set_node(&vol->dev, find_volume_fwnode(vol)); /* * Finish all pending erases because there may be some LEBs belonging @@ -605,6 +631,7 @@ int ubi_add_volume(struct ubi_device *ubi, struct ubi_volume *vol) vol->dev.class = &ubi_class; vol->dev.groups = volume_dev_groups; dev_set_name(&vol->dev, "%s_%d", ubi->ubi_name, vol->vol_id); + device_set_node(&vol->dev, find_volume_fwnode(vol)); err = device_register(&vol->dev); if (err) { cdev_del(&vol->cdev); From patchwork Sun Dec 17 00:10:31 2023 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Daniel Golle X-Patchwork-Id: 755704 Received: from pidgin.makrotopia.org (pidgin.makrotopia.org [185.142.180.65]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by smtp.subspace.kernel.org (Postfix) with ESMTPS id 000E64A39; Sun, 17 Dec 2023 00:10:42 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; dmarc=none (p=none dis=none) header.from=makrotopia.org Authentication-Results: smtp.subspace.kernel.org; spf=pass smtp.mailfrom=makrotopia.org Received: from local by pidgin.makrotopia.org with esmtpsa (TLS1.3:TLS_AES_256_GCM_SHA384:256) (Exim 4.96.2) (envelope-from ) id 1rEejp-00067N-0k; Sun, 17 Dec 2023 00:10:34 +0000 Date: Sun, 17 Dec 2023 00:10:31 +0000 From: Daniel Golle To: Miquel Raynal , Richard Weinberger , Vignesh Raghavendra , Rob Herring , Krzysztof Kozlowski , Conor Dooley , Daniel Golle , =?utf-8?b?UmFmYcWCIE1pxYJlY2tp?= , linux-mtd@lists.infradead.org, devicetree@vger.kernel.org, linux-kernel@vger.kernel.org Subject: [PATCH v5 7/7] mtd: ubi: provide NVMEM layer over UBI volumes Message-ID: <804cf1a611962cb28d71b8028fef5273a8e79ba0.1702770711.git.daniel@makrotopia.org> References: Precedence: bulk X-Mailing-List: devicetree@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Content-Disposition: inline In-Reply-To: In an ideal world we would like UBI to be used where ever possible on a NAND chip. And with UBI support in ARM Trusted Firmware and U-Boot it is possible to achieve an (almost-)all-UBI flash layout. Hence the need for a way to also use UBI volumes to store board-level constants, such as MAC addresses and calibration data of wireless interfaces. Add UBI volume NVMEM driver module exposing UBI volumes as NVMEM providers. Allow UBI devices to have a "volumes" firmware subnode with volumes which may be compatible with "nvmem-cells". Access to UBI volumes via the NVMEM interface at this point is read-only, and it is slow, opening and closing the UBI volume for each access due to limitations of the NVMEM provider API. Signed-off-by: Daniel Golle --- drivers/mtd/ubi/Kconfig | 12 +++ drivers/mtd/ubi/Makefile | 1 + drivers/mtd/ubi/nvmem.c | 188 +++++++++++++++++++++++++++++++++++++++ 3 files changed, 201 insertions(+) create mode 100644 drivers/mtd/ubi/nvmem.c diff --git a/drivers/mtd/ubi/Kconfig b/drivers/mtd/ubi/Kconfig index 2ed77b7b3fcb5..45d939bbfa853 100644 --- a/drivers/mtd/ubi/Kconfig +++ b/drivers/mtd/ubi/Kconfig @@ -104,4 +104,16 @@ config MTD_UBI_BLOCK If in doubt, say "N". +config MTD_UBI_NVMEM + tristate "UBI virtual NVMEM" + default n + depends on NVMEM + help + This option enabled an additional driver exposing UBI volumes as NVMEM + providers, intended for platforms where UBI is part of the firmware + specification and used to store also e.g. MAC addresses or board- + specific Wi-Fi calibration data. + + If in doubt, say "N". + endif # MTD_UBI diff --git a/drivers/mtd/ubi/Makefile b/drivers/mtd/ubi/Makefile index 543673605ca72..4b51aaf00d1a2 100644 --- a/drivers/mtd/ubi/Makefile +++ b/drivers/mtd/ubi/Makefile @@ -7,3 +7,4 @@ ubi-$(CONFIG_MTD_UBI_FASTMAP) += fastmap.o ubi-$(CONFIG_MTD_UBI_BLOCK) += block.o obj-$(CONFIG_MTD_UBI_GLUEBI) += gluebi.o +obj-$(CONFIG_MTD_UBI_NVMEM) += nvmem.o diff --git a/drivers/mtd/ubi/nvmem.c b/drivers/mtd/ubi/nvmem.c new file mode 100644 index 0000000000000..b7a93c495d172 --- /dev/null +++ b/drivers/mtd/ubi/nvmem.c @@ -0,0 +1,188 @@ +// SPDX-License-Identifier: GPL-2.0-or-later +/* + * Copyright (c) 2023 Daniel Golle + */ + +/* UBI NVMEM provider */ +#include "ubi.h" +#include +#include + +/* List of all NVMEM devices */ +static LIST_HEAD(nvmem_devices); +static DEFINE_MUTEX(devices_mutex); + +struct ubi_nvmem { + struct nvmem_device *nvmem; + int ubi_num; + int vol_id; + int usable_leb_size; + struct list_head list; +}; + +static int ubi_nvmem_reg_read(void *priv, unsigned int from, + void *val, size_t bytes) +{ + int err = 0, lnum = from, offs, bytes_left = bytes, to_read; + struct ubi_nvmem *unv = priv; + struct ubi_volume_desc *desc; + + desc = ubi_open_volume(unv->ubi_num, unv->vol_id, UBI_READONLY); + if (IS_ERR(desc)) + return PTR_ERR(desc); + + offs = do_div(lnum, unv->usable_leb_size); + while (bytes_left) { + to_read = unv->usable_leb_size - offs; + + if (to_read > bytes_left) + to_read = bytes_left; + + err = ubi_read(desc, lnum, val, offs, to_read); + if (err) + break; + + lnum += 1; + offs = 0; + bytes_left -= to_read; + val += to_read; + } + ubi_close_volume(desc); + + if (err) + return err; + + return bytes_left == 0 ? 0 : -EIO; +} + +static int ubi_nvmem_add(struct ubi_volume_info *vi) +{ + struct device_node *np = dev_of_node(vi->dev); + struct nvmem_config config = {}; + struct ubi_nvmem *unv; + int ret; + + if (!np) + return 0; + + if (!of_get_child_by_name(np, "nvmem-layout")) + return 0; + + if (WARN_ON_ONCE(vi->usable_leb_size <= 0) || + WARN_ON_ONCE(vi->size <= 0)) + return -EINVAL; + + unv = kzalloc(sizeof(struct ubi_nvmem), GFP_KERNEL); + if (!unv) + return -ENOMEM; + + config.id = NVMEM_DEVID_NONE; + config.dev = vi->dev; + config.name = dev_name(vi->dev); + config.owner = THIS_MODULE; + config.priv = unv; + config.reg_read = ubi_nvmem_reg_read; + config.size = vi->usable_leb_size * vi->size; + config.word_size = 1; + config.stride = 1; + config.read_only = true; + config.root_only = true; + config.ignore_wp = true; + config.of_node = np; + + unv->ubi_num = vi->ubi_num; + unv->vol_id = vi->vol_id; + unv->usable_leb_size = vi->usable_leb_size; + unv->nvmem = nvmem_register(&config); + if (IS_ERR(unv->nvmem)) { + ret = dev_err_probe(vi->dev, PTR_ERR(unv->nvmem), + "Failed to register NVMEM device\n"); + kfree(unv); + return ret; + } + + mutex_lock(&devices_mutex); + list_add_tail(&unv->list, &nvmem_devices); + mutex_unlock(&devices_mutex); + + return 0; +} + +static void ubi_nvmem_remove(struct ubi_volume_info *vi) +{ + struct ubi_nvmem *unv_c, *unv = NULL; + + mutex_lock(&devices_mutex); + list_for_each_entry(unv_c, &nvmem_devices, list) + if (unv_c->ubi_num == vi->ubi_num && unv_c->vol_id == vi->vol_id) { + unv = unv_c; + break; + } + + if (!unv) { + mutex_unlock(&devices_mutex); + return; + } + + list_del(&unv->list); + mutex_unlock(&devices_mutex); + nvmem_unregister(unv->nvmem); + kfree(unv); +} + +/** + * nvmem_notify - UBI notification handler. + * @nb: registered notifier block + * @l: notification type + * @ns_ptr: pointer to the &struct ubi_notification object + */ +static int nvmem_notify(struct notifier_block *nb, unsigned long l, + void *ns_ptr) +{ + struct ubi_notification *nt = ns_ptr; + + switch (l) { + case UBI_VOLUME_RESIZED: + ubi_nvmem_remove(&nt->vi); + fallthrough; + case UBI_VOLUME_ADDED: + ubi_nvmem_add(&nt->vi); + break; + case UBI_VOLUME_SHUTDOWN: + ubi_nvmem_remove(&nt->vi); + break; + default: + break; + } + return NOTIFY_OK; +} + +static struct notifier_block nvmem_notifier = { + .notifier_call = nvmem_notify, +}; + +static int __init ubi_nvmem_init(void) +{ + return ubi_register_volume_notifier(&nvmem_notifier, 0); +} + +static void __exit ubi_nvmem_exit(void) +{ + struct ubi_nvmem *unv, *tmp; + + mutex_lock(&devices_mutex); + list_for_each_entry_safe(unv, tmp, &nvmem_devices, list) { + nvmem_unregister(unv->nvmem); + list_del(&unv->list); + kfree(unv); + } + mutex_unlock(&devices_mutex); + + ubi_unregister_volume_notifier(&nvmem_notifier); +} + +module_init(ubi_nvmem_init); +module_exit(ubi_nvmem_exit); +MODULE_DESCRIPTION("NVMEM layer over UBI volumes"); +MODULE_AUTHOR("Daniel Golle"); +MODULE_LICENSE("GPL");