diff options
Diffstat (limited to 'linux-2.4.x/drivers/mtd/mtdcore.c')
| -rw-r--r-- | linux-2.4.x/drivers/mtd/mtdcore.c | 326 |
1 files changed, 165 insertions, 161 deletions
diff --git a/linux-2.4.x/drivers/mtd/mtdcore.c b/linux-2.4.x/drivers/mtd/mtdcore.c index d40f144..8fde482 100644 --- a/linux-2.4.x/drivers/mtd/mtdcore.c +++ b/linux-2.4.x/drivers/mtd/mtdcore.c @@ -1,5 +1,5 @@ /* - * $Id: mtdcore.c,v 1.32 2002/03/07 18:38:10 joern Exp $ + * $Id: mtdcore.c,v 1.49 2006/03/29 08:40:13 dwmw2 Exp $ * * Core registration and callback routines for MTD * drivers and users. @@ -17,17 +17,21 @@ #include <linux/major.h> #include <linux/fs.h> #include <linux/ioctl.h> -#include <stdarg.h> +#include <linux/init.h> #include <linux/mtd/compatmac.h> -#ifdef CONFIG_PROC_FS #include <linux/proc_fs.h> -#endif #include <linux/mtd/mtd.h> -static DECLARE_MUTEX(mtd_table_mutex); -static struct mtd_info *mtd_table[MAX_MTD_DEVICES]; -static struct mtd_notifier *mtd_notifiers = NULL; +/* These are exported solely for the purpose of mtd_blkdevs.c. You + should not use them for _anything_ else */ +DEFINE_MUTEX(mtd_table_mutex); +struct mtd_info *mtd_table[MAX_MTD_DEVICES]; + +EXPORT_SYMBOL_GPL(mtd_table_mutex); +EXPORT_SYMBOL_GPL(mtd_table); + +static LIST_HEAD(mtd_notifiers); /** * add_mtd_device - register an MTD device @@ -43,27 +47,34 @@ int add_mtd_device(struct mtd_info *mtd) { int i; - down(&mtd_table_mutex); + mutex_lock(&mtd_table_mutex); - for (i=0; i< MAX_MTD_DEVICES; i++) - if (!mtd_table[i]) - { - struct mtd_notifier *not=mtd_notifiers; + for (i=0; i < MAX_MTD_DEVICES; i++) + if (!mtd_table[i]) { + struct list_head *this; mtd_table[i] = mtd; mtd->index = i; + mtd->usecount = 0; + DEBUG(0, "mtd: Giving out device %d to %s\n",i, mtd->name); - while (not) - { - (*(not->add))(mtd); - not = not->next; + /* No need to get a refcount on the module containing + the notifier, since we hold the mtd_table_mutex */ + list_for_each(this, &mtd_notifiers) { + struct mtd_notifier *not = list_entry(this, struct mtd_notifier, list); + not->add(mtd); } - up(&mtd_table_mutex); - MOD_INC_USE_COUNT; + + mutex_unlock(&mtd_table_mutex); + /* We _know_ we aren't being removed, because + our caller is still holding us here. So none + of this try_ nonsense, and no bitching about it + either. :) */ + __module_get(THIS_MODULE); return 0; } - - up(&mtd_table_mutex); + + mutex_unlock(&mtd_table_mutex); return 1; } @@ -79,29 +90,34 @@ int add_mtd_device(struct mtd_info *mtd) int del_mtd_device (struct mtd_info *mtd) { - struct mtd_notifier *not=mtd_notifiers; - int i; - - down(&mtd_table_mutex); - - for (i=0; i < MAX_MTD_DEVICES; i++) - { - if (mtd_table[i] == mtd) - { - while (not) - { - (*(not->remove))(mtd); - not = not->next; - } - mtd_table[i] = NULL; - up (&mtd_table_mutex); - MOD_DEC_USE_COUNT; - return 0; + int ret; + + mutex_lock(&mtd_table_mutex); + + if (mtd_table[mtd->index] != mtd) { + ret = -ENODEV; + } else if (mtd->usecount) { + printk(KERN_NOTICE "Removing MTD device #%d (%s) with use count %d\n", + mtd->index, mtd->name, mtd->usecount); + ret = -EBUSY; + } else { + struct list_head *this; + + /* No need to get a refcount on the module containing + the notifier, since we hold the mtd_table_mutex */ + list_for_each(this, &mtd_notifiers) { + struct mtd_notifier *not = list_entry(this, struct mtd_notifier, list); + not->remove(mtd); } + + mtd_table[mtd->index] = NULL; + + module_put(THIS_MODULE); + ret = 0; } - up(&mtd_table_mutex); - return 1; + mutex_unlock(&mtd_table_mutex); + return ret; } /** @@ -117,23 +133,22 @@ void register_mtd_user (struct mtd_notifier *new) { int i; - down(&mtd_table_mutex); + mutex_lock(&mtd_table_mutex); - new->next = mtd_notifiers; - mtd_notifiers = new; + list_add(&new->list, &mtd_notifiers); + + __module_get(THIS_MODULE); - MOD_INC_USE_COUNT; - for (i=0; i< MAX_MTD_DEVICES; i++) if (mtd_table[i]) new->add(mtd_table[i]); - up(&mtd_table_mutex); + mutex_unlock(&mtd_table_mutex); } /** - * register_mtd_user - unregister a 'user' of MTD devices. - * @new: pointer to notifier info structure + * unregister_mtd_user - unregister a 'user' of MTD devices. + * @old: pointer to notifier info structure * * Removes a callback function pair from the list of 'users' to be * notified upon addition or removal of MTD devices. Causes the @@ -143,34 +158,24 @@ void register_mtd_user (struct mtd_notifier *new) int unregister_mtd_user (struct mtd_notifier *old) { - struct mtd_notifier **prev = &mtd_notifiers; - struct mtd_notifier *cur; int i; - down(&mtd_table_mutex); + mutex_lock(&mtd_table_mutex); - while ((cur = *prev)) { - if (cur == old) { - *prev = cur->next; + module_put(THIS_MODULE); - MOD_DEC_USE_COUNT; + for (i=0; i< MAX_MTD_DEVICES; i++) + if (mtd_table[i]) + old->remove(mtd_table[i]); - for (i=0; i< MAX_MTD_DEVICES; i++) - if (mtd_table[i]) - old->remove(mtd_table[i]); - - up(&mtd_table_mutex); - return 0; - } - prev = &cur->next; - } - up(&mtd_table_mutex); - return 1; + list_del(&old->list); + mutex_unlock(&mtd_table_mutex); + return 0; } /** - * __get_mtd_device - obtain a validated handle for an MTD device + * get_mtd_device - obtain a validated handle for an MTD device * @mtd: last known address of the required MTD device * @num: internal device number of the required MTD device * @@ -178,16 +183,15 @@ int unregister_mtd_user (struct mtd_notifier *old) * table, if any. Given an address and num == -1, search the device table * for a device with that address and return if it's still present. Given * both, return the num'th driver only if its address matches. Return NULL - * if not. get_mtd_device() increases the use count, but - * __get_mtd_device() doesn't - you should generally use get_mtd_device(). + * if not. */ - -struct mtd_info *__get_mtd_device(struct mtd_info *mtd, int num) + +struct mtd_info *get_mtd_device(struct mtd_info *mtd, int num) { struct mtd_info *ret = NULL; int i; - down(&mtd_table_mutex); + mutex_lock(&mtd_table_mutex); if (num == -1) { for (i=0; i< MAX_MTD_DEVICES; i++) @@ -198,58 +202,104 @@ struct mtd_info *__get_mtd_device(struct mtd_info *mtd, int num) if (mtd && mtd != ret) ret = NULL; } - - up(&mtd_table_mutex); + + if (ret && !try_module_get(ret->owner)) + ret = NULL; + + if (ret) + ret->usecount++; + + mutex_unlock(&mtd_table_mutex); return ret; } -EXPORT_SYMBOL(add_mtd_device); -EXPORT_SYMBOL(del_mtd_device); -EXPORT_SYMBOL(__get_mtd_device); -EXPORT_SYMBOL(register_mtd_user); -EXPORT_SYMBOL(unregister_mtd_user); - -/*====================================================================*/ -/* Power management code */ +void put_mtd_device(struct mtd_info *mtd) +{ + int c; -#ifdef CONFIG_PM + mutex_lock(&mtd_table_mutex); + c = --mtd->usecount; + mutex_unlock(&mtd_table_mutex); + BUG_ON(c < 0); -#include <linux/pm.h> + module_put(mtd->owner); +} -static struct pm_dev *mtd_pm_dev = NULL; +/* default_mtd_writev - default mtd writev method for MTD devices that + * dont implement their own + */ -static int mtd_pm_callback(struct pm_dev *dev, pm_request_t rqst, void *data) +int default_mtd_writev(struct mtd_info *mtd, const struct kvec *vecs, + unsigned long count, loff_t to, size_t *retlen) { - int ret = 0, i; - - if (down_trylock(&mtd_table_mutex)) - return -EAGAIN; - if (rqst == PM_SUSPEND) { - for (i = 0; ret == 0 && i < MAX_MTD_DEVICES; i++) { - if (mtd_table[i] && mtd_table[i]->suspend) - ret = mtd_table[i]->suspend(mtd_table[i]); + unsigned long i; + size_t totlen = 0, thislen; + int ret = 0; + + if(!mtd->write) { + ret = -EROFS; + } else { + for (i=0; i<count; i++) { + if (!vecs[i].iov_len) + continue; + ret = mtd->write(mtd, to, vecs[i].iov_len, &thislen, vecs[i].iov_base); + totlen += thislen; + if (ret || thislen != vecs[i].iov_len) + break; + to += vecs[i].iov_len; } - } else i = MAX_MTD_DEVICES-1; + } + if (retlen) + *retlen = totlen; + return ret; +} + + +/* default_mtd_readv - default mtd readv method for MTD devices that dont + * implement their own + */ - if (rqst == PM_RESUME || ret) { - for ( ; i >= 0; i--) { - if (mtd_table[i] && mtd_table[i]->resume) - mtd_table[i]->resume(mtd_table[i]); +int default_mtd_readv(struct mtd_info *mtd, struct kvec *vecs, + unsigned long count, loff_t from, size_t *retlen) +{ + unsigned long i; + size_t totlen = 0, thislen; + int ret = 0; + + if(!mtd->read) { + ret = -EIO; + } else { + for (i=0; i<count; i++) { + if (!vecs[i].iov_len) + continue; + ret = mtd->read(mtd, from, vecs[i].iov_len, &thislen, vecs[i].iov_base); + totlen += thislen; + if (ret || thislen != vecs[i].iov_len) + break; + from += vecs[i].iov_len; } } - up(&mtd_table_mutex); + if (retlen) + *retlen = totlen; return ret; } -#endif -/*====================================================================*/ -/* Support for /proc/mtd */ + +EXPORT_SYMBOL(add_mtd_device); +EXPORT_SYMBOL(del_mtd_device); +EXPORT_SYMBOL(get_mtd_device); +EXPORT_SYMBOL(put_mtd_device); +EXPORT_SYMBOL(register_mtd_user); +EXPORT_SYMBOL(unregister_mtd_user); +EXPORT_SYMBOL(default_mtd_writev); +EXPORT_SYMBOL(default_mtd_readv); #ifdef CONFIG_PROC_FS -#if LINUX_VERSION_CODE >= KERNEL_VERSION(2,2,0) +/*====================================================================*/ +/* Support for /proc/mtd */ + static struct proc_dir_entry *proc_mtd; -#endif static inline int mtd_proc_info (char *buf, int i) { @@ -262,18 +312,13 @@ static inline int mtd_proc_info (char *buf, int i) this->erasesize, this->name); } -static int mtd_read_proc ( char *page, char **start, off_t off,int count -#if LINUX_VERSION_CODE >= KERNEL_VERSION(2,2,0) - ,int *eof, void *data_unused -#else - ,int unused -#endif - ) +static int mtd_read_proc (char *page, char **start, off_t off, int count, + int *eof, void *data_unused) { int len, l, i; off_t begin = 0; - down(&mtd_table_mutex); + mutex_lock(&mtd_table_mutex); len = sprintf(page, "dev: size erasesize name\n"); for (i=0; i< MAX_MTD_DEVICES; i++) { @@ -288,78 +333,37 @@ static int mtd_read_proc ( char *page, char **start, off_t off,int count } } -#if LINUX_VERSION_CODE >= KERNEL_VERSION(2,2,0) *eof = 1; -#endif done: - up(&mtd_table_mutex); + mutex_unlock(&mtd_table_mutex); if (off >= len+begin) return 0; *start = page + (off-begin); return ((count < begin+len-off) ? count : begin+len-off); } -#if LINUX_VERSION_CODE < KERNEL_VERSION(2,2,0) -struct proc_dir_entry mtd_proc_entry = { - 0, /* low_ino: the inode -- dynamic */ - 3, "mtd", /* len of name and name */ - S_IFREG | S_IRUGO, /* mode */ - 1, 0, 0, /* nlinks, owner, group */ - 0, NULL, /* size - unused; operations -- use default */ - &mtd_read_proc, /* function used to read data */ - /* nothing more */ - }; -#endif - -#endif /* CONFIG_PROC_FS */ - /*====================================================================*/ /* Init code */ -int __init init_mtd(void) +static int __init init_mtd(void) { -#ifdef CONFIG_PROC_FS -#if LINUX_VERSION_CODE >= KERNEL_VERSION(2,2,0) - if ((proc_mtd = create_proc_entry( "mtd", 0, 0 ))) - proc_mtd->read_proc = mtd_read_proc; -#else - proc_register_dynamic(&proc_root,&mtd_proc_entry); -#endif -#endif - -#if LINUX_VERSION_CODE < 0x20212 - init_mtd_devices(); -#endif - -#ifdef CONFIG_PM - mtd_pm_dev = pm_register(PM_UNKNOWN_DEV, 0, mtd_pm_callback); -#endif + if ((proc_mtd = create_proc_entry( "mtd", 0, NULL ))) + proc_mtd->read_proc = mtd_read_proc; return 0; } static void __exit cleanup_mtd(void) { -#ifdef CONFIG_PM - if (mtd_pm_dev) { - pm_unregister(mtd_pm_dev); - mtd_pm_dev = NULL; - } -#endif - -#ifdef CONFIG_PROC_FS -#if LINUX_VERSION_CODE >= KERNEL_VERSION(2,2,0) if (proc_mtd) - remove_proc_entry( "mtd", 0); -#else - proc_unregister(&proc_root,mtd_proc_entry.low_ino); -#endif -#endif + remove_proc_entry( "mtd", NULL); } module_init(init_mtd); module_exit(cleanup_mtd); +#endif /* CONFIG_PROC_FS */ + MODULE_LICENSE("GPL"); MODULE_AUTHOR("David Woodhouse <dwmw2@infradead.org>"); |