The series is a follow-up and contains all patches of the previous
series "mtd: ubi: behave like a good MTD citizen"[1] which was meant in
preparation for implementing the NVMEM provider.
The goal is to support embedded Linux devices which got NVMEM bits
stored inside a UBI volume. Representing the UBI volume in the Device
Tree, adding a phandle to be referenced by NVMEM consumers allows such
devices to come up with their correct MAC addresses and device-specific
Wi-Fi calibration data loaded.
In order to be available for other drivers, attaching UBI devices has
to be moved from late_initcall (which is too late for other drivers) to
happen earlier. As an alternative to the existing kernel cmdline
parameter the Device Tree property 'compatible = "linux,ubi";' inside
an MTD partition can be used to have that MTD device attached as UBI
device. MTD partitions which serve as UBI devices may have a "volumes"
firmware subnode with volumes which may be compatible with
"nvmem-cells".
In this way, other drivers (think: Ethernet, Wi-Fi) can resolve and
acquire NVMEM bits using the usual device tree phandle, just this time
the NVMEM content is read from a UBI volume.
[1]: https://patchwork.ozlabs.org/project/linux-mtd/list/?series=353177&state=%2A&archive=both
Changes since v1:
* include patch to fix exiting Kconfig formatting issues
* fix typo and indentation in Kconfig
Daniel Golle (7):
mtd: ubi: improve Kconfig formatting
mtd: ubi: block: don't return on error when removing
mtd: ubi: block: use notifier to create ubiblock from parameter
mtd: ubi: attach MTD partition from device-tree
mtd: ubi: introduce pre-removal notification for UBI volumes
mtd: ubi: populate ubi volume fwnode
mtd: ubi: provide NVMEM layer over UBI volumes
drivers/mtd/ubi/Kconfig | 72 ++++++++-------
drivers/mtd/ubi/Makefile | 1 +
drivers/mtd/ubi/block.c | 186 +++++++++++++++++++++++---------------
drivers/mtd/ubi/build.c | 160 ++++++++++++++++++++++++---------
drivers/mtd/ubi/cdev.c | 4 +-
drivers/mtd/ubi/nvmem.c | 189 +++++++++++++++++++++++++++++++++++++++
drivers/mtd/ubi/ubi.h | 6 +-
drivers/mtd/ubi/vmt.c | 36 ++++++++
include/linux/mtd/ubi.h | 2 +
9 files changed, 507 insertions(+), 149 deletions(-)
create mode 100644 drivers/mtd/ubi/nvmem.c
--
2.41.0
There is no point on returning the error from ubiblock_remove in case
it is being called due to a volume removal event -- the volume is gone,
we should destroy and remove the ubiblock device no matter what.
Introduce new boolean parameter 'force' to tell ubiblock_remove to go
on even in case the ubiblock device is still busy. Use that new option
when calling ubiblock_remove due to a UBI_VOLUME_REMOVED event.
Signed-off-by: Daniel Golle <[email protected]>
---
drivers/mtd/ubi/block.c | 6 +++---
drivers/mtd/ubi/cdev.c | 2 +-
drivers/mtd/ubi/ubi.h | 4 ++--
3 files changed, 6 insertions(+), 6 deletions(-)
diff --git a/drivers/mtd/ubi/block.c b/drivers/mtd/ubi/block.c
index 437c5b83ffe51..69fa6fecb8494 100644
--- a/drivers/mtd/ubi/block.c
+++ b/drivers/mtd/ubi/block.c
@@ -456,7 +456,7 @@ static void ubiblock_cleanup(struct ubiblock *dev)
idr_remove(&ubiblock_minor_idr, dev->gd->first_minor);
}
-int ubiblock_remove(struct ubi_volume_info *vi)
+int ubiblock_remove(struct ubi_volume_info *vi, bool force)
{
struct ubiblock *dev;
int ret;
@@ -470,7 +470,7 @@ int ubiblock_remove(struct ubi_volume_info *vi)
/* Found a device, let's lock it so we can check if it's busy */
mutex_lock(&dev->dev_mutex);
- if (dev->refcnt > 0) {
+ if (dev->refcnt > 0 && !force) {
ret = -EBUSY;
goto out_unlock_dev;
}
@@ -545,7 +545,7 @@ static int ubiblock_notify(struct notifier_block *nb,
*/
break;
case UBI_VOLUME_REMOVED:
- ubiblock_remove(&nt->vi);
+ ubiblock_remove(&nt->vi, true);
break;
case UBI_VOLUME_RESIZED:
ubiblock_resize(&nt->vi);
diff --git a/drivers/mtd/ubi/cdev.c b/drivers/mtd/ubi/cdev.c
index f43430b9c1e65..bb55e863dd296 100644
--- a/drivers/mtd/ubi/cdev.c
+++ b/drivers/mtd/ubi/cdev.c
@@ -572,7 +572,7 @@ static long vol_cdev_ioctl(struct file *file, unsigned int cmd,
struct ubi_volume_info vi;
ubi_get_volume_info(desc, &vi);
- err = ubiblock_remove(&vi);
+ err = ubiblock_remove(&vi, false);
break;
}
diff --git a/drivers/mtd/ubi/ubi.h b/drivers/mtd/ubi/ubi.h
index c8f1bd4fa1008..44c0eeaf1e1b0 100644
--- a/drivers/mtd/ubi/ubi.h
+++ b/drivers/mtd/ubi/ubi.h
@@ -979,7 +979,7 @@ static inline void ubi_fastmap_destroy_checkmap(struct ubi_volume *vol) {}
int ubiblock_init(void);
void ubiblock_exit(void);
int ubiblock_create(struct ubi_volume_info *vi);
-int ubiblock_remove(struct ubi_volume_info *vi);
+int ubiblock_remove(struct ubi_volume_info *vi, bool force);
#else
static inline int ubiblock_init(void) { return 0; }
static inline void ubiblock_exit(void) {}
@@ -987,7 +987,7 @@ static inline int ubiblock_create(struct ubi_volume_info *vi)
{
return -ENOSYS;
}
-static inline int ubiblock_remove(struct ubi_volume_info *vi)
+static inline int ubiblock_remove(struct ubi_volume_info *vi, bool force)
{
return -ENOSYS;
}
--
2.41.0
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 <[email protected]>
---
drivers/mtd/ubi/Kconfig | 12 +++
drivers/mtd/ubi/Makefile | 1 +
drivers/mtd/ubi/nvmem.c | 189 +++++++++++++++++++++++++++++++++++++++
3 files changed, 202 insertions(+)
create mode 100644 drivers/mtd/ubi/nvmem.c
diff --git a/drivers/mtd/ubi/Kconfig b/drivers/mtd/ubi/Kconfig
index 184118f9a2969..fb15d4549d55f 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 enables 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..dd7cc6afb8d00
--- /dev/null
+++ b/drivers/mtd/ubi/nvmem.c
@@ -0,0 +1,189 @@
+// SPDX-License-Identifier: GPL-2.0-or-later
+/*
+ * Copyright (c) 2023 Daniel Golle <[email protected]>
+ */
+
+/* UBI NVMEM provider */
+#include "ubi.h"
+#include <linux/nvmem-provider.h>
+
+/* 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)
+{
+ struct ubi_nvmem *unv = priv;
+ struct ubi_volume_desc *desc;
+ int err = 0, lnum, offs, bytes_left;
+ size_t to_read;
+
+ desc = ubi_open_volume(unv->ubi_num, unv->vol_id, UBI_READONLY);
+ if (IS_ERR(desc))
+ return PTR_ERR(desc);
+
+ lnum = div_u64_rem(from, unv->usable_leb_size, &offs);
+ bytes_left = bytes;
+ 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 nvmem_config config = {};
+ struct ubi_nvmem *unv;
+ int ret;
+
+ if (!device_is_compatible(vi->dev, "nvmem-cells"))
+ return 0;
+
+ 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 = dev_of_node(vi->dev);
+
+ if (!config.of_node)
+ config.no_of_node = true;
+
+ 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)) {
+ /* Just ignore if there is no NVMEM support in the kernel */
+ if (PTR_ERR(unv->nvmem) == -EOPNOTSUPP)
+ ret = 0;
+ else
+ 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");
--
2.41.0
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 <[email protected]>
---
drivers/mtd/ubi/block.c | 26 ++++++++++++++++++++++++++
drivers/mtd/ubi/build.c | 7 ++++++-
drivers/mtd/ubi/vmt.c | 5 +++++
include/linux/mtd/ubi.h | 2 ++
4 files changed, 39 insertions(+), 1 deletion(-)
diff --git a/drivers/mtd/ubi/block.c b/drivers/mtd/ubi/block.c
index 99b5f502c9dbc..1d5148371991b 100644
--- a/drivers/mtd/ubi/block.c
+++ b/drivers/mtd/ubi/block.c
@@ -533,6 +533,29 @@ static int ubiblock_resize(struct ubi_volume_info *vi)
return 0;
}
+static int ubiblock_shutdown(struct ubi_volume_info *vi)
+{
+ struct ubiblock *dev;
+ struct gendisk *disk;
+ int ret = 0;
+
+ mutex_lock(&devices_mutex);
+ dev = find_dev_nolock(vi->ubi_num, vi->vol_id);
+ if (!dev) {
+ ret = -ENODEV;
+ goto out_unlock;
+ }
+ disk = dev->gd;
+
+out_unlock:
+ mutex_unlock(&devices_mutex);
+
+ if (!ret)
+ blk_mark_disk_dead(disk);
+
+ return ret;
+};
+
static bool
match_volume_desc(struct ubi_volume_info *vi, const char *name, int ubi_num, int vol_id)
{
@@ -624,6 +647,9 @@ static int ubiblock_notify(struct notifier_block *nb,
case UBI_VOLUME_REMOVED:
ubiblock_remove(&nt->vi, true);
break;
+ case UBI_VOLUME_SHUTDOWN:
+ ubiblock_shutdown(&nt->vi);
+ break;
case UBI_VOLUME_RESIZED:
ubiblock_resize(&nt->vi);
break;
diff --git a/drivers/mtd/ubi/build.c b/drivers/mtd/ubi/build.c
index c153373c13dab..ccee4a28ffe97 100644
--- a/drivers/mtd/ubi/build.c
+++ b/drivers/mtd/ubi/build.c
@@ -1088,7 +1088,6 @@ int ubi_detach_mtd_dev(int ubi_num, int anyway, bool have_lock)
return -EINVAL;
spin_lock(&ubi_devices_lock);
- put_device(&ubi->dev);
ubi->ref_count -= 1;
if (ubi->ref_count) {
if (!anyway) {
@@ -1099,6 +1098,12 @@ int ubi_detach_mtd_dev(int ubi_num, int anyway, bool have_lock)
ubi_err(ubi, "%s reference count %d, destroy anyway",
ubi->ubi_name, ubi->ref_count);
}
+ 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/vmt.c b/drivers/mtd/ubi/vmt.c
index 2c867d16f89f7..eed4b57c61bda 100644
--- a/drivers/mtd/ubi/vmt.c
+++ b/drivers/mtd/ubi/vmt.c
@@ -352,6 +352,11 @@ int ubi_remove_volume(struct ubi_volume_desc *desc, int no_vtbl)
err = -EBUSY;
goto out_unlock;
}
+ 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 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,
};
--
2.41.0
Split ubi_init() function into early function to be called by
device_initcall() and keep cmdline attachment in late_initcall().
(when building ubi as module, both is still done in a single
module_init() call)
Register MTD notifier and attach MTD devices which are marked as
compatible with 'linux,ubi' in OF device-tree when being added, detach
UBI device from MTD device when it is being removed.
For existing users this should not change anything besides automatic
removal of (dead) UBI devices when their underlying MTD devices are
already gone, e.g. in case of MTD driver module or (SPI) bus driver
module being removed.
For new users this opens up the option to attach UBI using device-tree
which then happens early and in parallel with other drivers being
probed which slightly reduces the total boot time.
Attachment no longer happening late is also a requirement for other
drivers to make use of UBI, e.g. drivers/nvmem/u-boot-env.c can now
be extended to support U-Boot environment stored in UBI volumes.
Signed-off-by: Daniel Golle <[email protected]>
---
drivers/mtd/ubi/block.c | 2 +-
drivers/mtd/ubi/build.c | 153 +++++++++++++++++++++++++++++-----------
drivers/mtd/ubi/cdev.c | 2 +-
drivers/mtd/ubi/ubi.h | 2 +-
4 files changed, 115 insertions(+), 44 deletions(-)
diff --git a/drivers/mtd/ubi/block.c b/drivers/mtd/ubi/block.c
index e0618bbde3613..99b5f502c9dbc 100644
--- a/drivers/mtd/ubi/block.c
+++ b/drivers/mtd/ubi/block.c
@@ -470,7 +470,7 @@ int ubiblock_remove(struct ubi_volume_info *vi, bool force)
}
/* Found a device, let's lock it so we can check if it's busy */
- mutex_lock(&dev->dev_mutex);
+ mutex_lock_nested(&dev->dev_mutex, SINGLE_DEPTH_NESTING);
if (dev->refcnt > 0 && !force) {
ret = -EBUSY;
goto out_unlock_dev;
diff --git a/drivers/mtd/ubi/build.c b/drivers/mtd/ubi/build.c
index 8b91a55ec0d28..c153373c13dab 100644
--- a/drivers/mtd/ubi/build.c
+++ b/drivers/mtd/ubi/build.c
@@ -27,6 +27,7 @@
#include <linux/log2.h>
#include <linux/kthread.h>
#include <linux/kernel.h>
+#include <linux/of.h>
#include <linux/slab.h>
#include <linux/major.h>
#include "ubi.h"
@@ -1065,6 +1066,7 @@ int ubi_attach_mtd_dev(struct mtd_info *mtd, int ubi_num,
* ubi_detach_mtd_dev - detach an MTD device.
* @ubi_num: UBI device number to detach from
* @anyway: detach MTD even if device reference count is not zero
+ * @have_lock: called by MTD notifier holding mtd_table_mutex
*
* This function destroys an UBI device number @ubi_num and detaches the
* underlying MTD device. Returns zero in case of success and %-EBUSY if the
@@ -1074,7 +1076,7 @@ int ubi_attach_mtd_dev(struct mtd_info *mtd, int ubi_num,
* Note, the invocations of this function has to be serialized by the
* @ubi_devices_mutex.
*/
-int ubi_detach_mtd_dev(int ubi_num, int anyway)
+int ubi_detach_mtd_dev(int ubi_num, int anyway, bool have_lock)
{
struct ubi_device *ubi;
@@ -1111,6 +1113,7 @@ int ubi_detach_mtd_dev(int ubi_num, int anyway)
if (!ubi_dbg_chk_fastmap(ubi))
ubi_update_fastmap(ubi);
#endif
+
/*
* Before freeing anything, we have to stop the background thread to
* prevent it from doing anything on this device while we are freeing.
@@ -1130,7 +1133,11 @@ int ubi_detach_mtd_dev(int ubi_num, int anyway)
vfree(ubi->peb_buf);
vfree(ubi->fm_buf);
ubi_msg(ubi, "mtd%d is detached", ubi->mtd->index);
- put_mtd_device(ubi->mtd);
+ if (have_lock)
+ __put_mtd_device(ubi->mtd);
+ else
+ put_mtd_device(ubi->mtd);
+
put_device(&ubi->dev);
return 0;
}
@@ -1207,43 +1214,51 @@ 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);
+ mutex_unlock(&ubi_devices_mutex);
if (err < 0)
- return err;
+ __put_mtd_device(mtd);
+}
- err = misc_register(&ubi_ctrl_cdev);
- if (err) {
- pr_err("UBI error: cannot register device\n");
- goto out;
- }
+static void ubi_notify_remove(struct mtd_info *mtd)
+{
+ int i;
- 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;
- }
+ /* called while holding mtd_table_mutex */
+ mutex_lock_nested(&ubi_devices_mutex, SINGLE_DEPTH_NESTING);
+ for (i = 0; i < UBI_MAX_DEVICES; i++)
+ if (ubi_devices[i] &&
+ ubi_devices[i]->mtd->index == mtd->index)
+ ubi_detach_mtd_dev(ubi_devices[i]->ubi_num, 1, true);
+ mutex_unlock(&ubi_devices_mutex);
+}
- 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++) {
@@ -1291,25 +1306,79 @@ 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, false);
+ 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:
@@ -1319,18 +1388,20 @@ 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]) {
mutex_lock(&ubi_devices_mutex);
- ubi_detach_mtd_dev(ubi_devices[i]->ubi_num, 1);
+ ubi_detach_mtd_dev(ubi_devices[i]->ubi_num, 1, false);
mutex_unlock(&ubi_devices_mutex);
}
ubi_debugfs_exit();
diff --git a/drivers/mtd/ubi/cdev.c b/drivers/mtd/ubi/cdev.c
index bb55e863dd296..0ba6aa6a2e11d 100644
--- a/drivers/mtd/ubi/cdev.c
+++ b/drivers/mtd/ubi/cdev.c
@@ -1065,7 +1065,7 @@ static long ctrl_cdev_ioctl(struct file *file, unsigned int cmd,
}
mutex_lock(&ubi_devices_mutex);
- err = ubi_detach_mtd_dev(ubi_num, 0);
+ err = ubi_detach_mtd_dev(ubi_num, 0, false);
mutex_unlock(&ubi_devices_mutex);
break;
}
diff --git a/drivers/mtd/ubi/ubi.h b/drivers/mtd/ubi/ubi.h
index 44c0eeaf1e1b0..54093858f3385 100644
--- a/drivers/mtd/ubi/ubi.h
+++ b/drivers/mtd/ubi/ubi.h
@@ -939,7 +939,7 @@ int ubi_io_write_vid_hdr(struct ubi_device *ubi, int pnum,
int ubi_attach_mtd_dev(struct mtd_info *mtd, int ubi_num,
int vid_hdr_offset, int max_beb_per1024,
bool disable_fm);
-int ubi_detach_mtd_dev(int ubi_num, int anyway);
+int ubi_detach_mtd_dev(int ubi_num, int anyway, bool have_lock);
struct ubi_device *ubi_get_device(int ubi_num);
void ubi_put_device(struct ubi_device *ubi);
struct ubi_device *ubi_get_by_major(int major);
--
2.41.0
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 <[email protected]>
---
drivers/mtd/ubi/vmt.c | 31 +++++++++++++++++++++++++++++++
1 file changed, 31 insertions(+)
diff --git a/drivers/mtd/ubi/vmt.c b/drivers/mtd/ubi/vmt.c
index eed4b57c61bda..3b997256cfba7 100644
--- a/drivers/mtd/ubi/vmt.c
+++ b/drivers/mtd/ubi/vmt.c
@@ -124,6 +124,35 @@ 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 reg;
+
+ 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;
+
+ /*
+ * volume id (reg) in device tree greater than UBI_MAX_VOLUMES
+ * can be used to match by volname only
+ */
+ if (!fwnode_property_read_u32(fw_vol, "reg", ®) &&
+ reg < UBI_MAX_VOLUMES && vol->vol_id != reg)
+ continue;
+
+ return fw_vol;
+ }
+
+ return NULL;
+}
+
/**
* ubi_create_volume - create volume.
* @ubi: UBI device description object
@@ -223,6 +252,7 @@ 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
@@ -597,6 +627,7 @@ 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);
--
2.41.0