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author | Artem Bityutskiy <Artem.Bityutskiy@nokia.com> | 2007-12-16 16:59:31 +0200 |
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committer | Artem Bityutskiy <Artem.Bityutskiy@nokia.com> | 2007-12-26 19:15:17 +0200 |
commit | 9f961b57568960a150cc9781c52824c9093a0514 (patch) | |
tree | 345d60347d63bdc9973a2447d84024776b73dd2f /drivers/mtd/ubi/build.c | |
parent | 16f557ecbf96dd13d13788a6f62d4d97ae73b1f9 (diff) | |
download | op-kernel-dev-9f961b57568960a150cc9781c52824c9093a0514.zip op-kernel-dev-9f961b57568960a150cc9781c52824c9093a0514.tar.gz |
UBI: add UBI control device
This patch is a preparation to make UBI devices dynamic. It
adds an UBI control device which has dynamically allocated
major number and registers itself as "ubi_ctrl". It does not
do anything so far. The idea is that this device will allow
to attach/detach MTD devices from userspace.
This is symilar to what the Linux device mapper has.
The next things to do are:
* Fix UBI, because it now assumes UBI devices cannot go away
* Implement control device ioctls which will attach/detach MTD
devices
Signed-off-by: Artem Bityutskiy <Artem.Bityutskiy@nokia.com>
Diffstat (limited to 'drivers/mtd/ubi/build.c')
-rw-r--r-- | drivers/mtd/ubi/build.c | 52 |
1 files changed, 42 insertions, 10 deletions
diff --git a/drivers/mtd/ubi/build.c b/drivers/mtd/ubi/build.c index b3efb2f..3f37b16 100644 --- a/drivers/mtd/ubi/build.c +++ b/drivers/mtd/ubi/build.c @@ -21,11 +21,16 @@ */ /* - * This file includes UBI initialization and building of UBI devices. At the - * moment UBI devices may only be added while UBI is initialized, but dynamic - * device add/remove functionality is planned. Also, at the moment we only - * attach UBI devices by scanning, which will become a bottleneck when flashes - * reach certain large size. Then one may improve UBI and add other methods. + * This file includes UBI initialization and building of UBI devices. + * + * When UBI is initialized, it attaches all the MTD devices specified as the + * module load parameters or the kernel boot parameters. If MTD devices were + * specified, UBI does not attach any MTD device, but it is possible to do + * later using the "UBI control device". + * + * At the moment we only attach UBI devices by scanning, which will become a + * bottleneck when flashes reach certain large size. Then one may improve UBI + * and add other methods, although it does not seem to be easy to do. */ #include <linux/err.h> @@ -33,6 +38,7 @@ #include <linux/moduleparam.h> #include <linux/stringify.h> #include <linux/stat.h> +#include <linux/miscdevice.h> #include <linux/log2.h> #include "ubi.h" @@ -70,6 +76,12 @@ struct kmem_cache *ubi_ltree_slab; /* Slab cache for wear-leveling entries */ struct kmem_cache *ubi_wl_entry_slab; +/* UBI control character device */ +static struct miscdevice ubi_ctrl_cdev = { + .minor = MISC_DYNAMIC_MINOR, + .name = "ubi_ctrl", + .fops = &ubi_ctrl_cdev_operations, +}; /* "Show" method for files in '/<sysfs>/class/ubi/' */ static ssize_t ubi_version_show(struct class *class, char *buf) @@ -701,19 +713,31 @@ static int __init ubi_init(void) return -EINVAL; } + /* Create base sysfs directory and sysfs files */ ubi_class = class_create(THIS_MODULE, UBI_NAME_STR); - if (IS_ERR(ubi_class)) - return PTR_ERR(ubi_class); + if (IS_ERR(ubi_class)) { + err = PTR_ERR(ubi_class); + printk(KERN_ERR "UBI error: cannot create UBI class\n"); + goto out; + } err = class_create_file(ubi_class, &ubi_version); - if (err) + if (err) { + printk(KERN_ERR "UBI error: cannot create sysfs file\n"); goto out_class; + } + + err = misc_register(&ubi_ctrl_cdev); + if (err) { + printk(KERN_ERR "UBI error: cannot register device\n"); + goto out_version; + } ubi_ltree_slab = kmem_cache_create("ubi_ltree_slab", sizeof(struct ubi_ltree_entry), 0, 0, <ree_entry_ctor); if (!ubi_ltree_slab) - goto out_version; + goto out_dev_unreg; ubi_wl_entry_slab = kmem_cache_create("ubi_wl_entry_slab", sizeof(struct ubi_wl_entry), @@ -727,8 +751,11 @@ static int __init ubi_init(void) cond_resched(); err = attach_mtd_dev(p->name, p->vid_hdr_offs, p->data_offs); - if (err) + if (err) { + printk(KERN_ERR "UBI error: cannot attach %s\n", + p->name); goto out_detach; + } } return 0; @@ -739,10 +766,14 @@ out_detach: kmem_cache_destroy(ubi_wl_entry_slab); out_ltree: kmem_cache_destroy(ubi_ltree_slab); +out_dev_unreg: + misc_deregister(&ubi_ctrl_cdev); out_version: class_remove_file(ubi_class, &ubi_version); out_class: class_destroy(ubi_class); +out: + printk(KERN_ERR "UBI error: cannot initialize UBI, error %d\n", err); return err; } module_init(ubi_init); @@ -756,6 +787,7 @@ static void __exit ubi_exit(void) detach_mtd_dev(ubi_devices[i]); kmem_cache_destroy(ubi_wl_entry_slab); kmem_cache_destroy(ubi_ltree_slab); + misc_deregister(&ubi_ctrl_cdev); class_remove_file(ubi_class, &ubi_version); class_destroy(ubi_class); } |