* Core registration and callback routines for MTD
* drivers and users.
*
+ * bdi bits are:
+ * Copyright © 2006 Red Hat, Inc. All Rights Reserved.
+ * Written by David Howells (dhowells@redhat.com)
*/
#include <linux/module.h>
#include <linux/kernel.h>
#include <linux/ptrace.h>
-#include <linux/slab.h>
#include <linux/string.h>
#include <linux/timer.h>
#include <linux/major.h>
#include <linux/init.h>
#include <linux/mtd/compatmac.h>
#include <linux/proc_fs.h>
+#include <linux/idr.h>
+#include <linux/backing-dev.h>
+#include <linux/gfp.h>
#include <linux/mtd/mtd.h>
#include "mtdcore.h"
+/*
+ * backing device capabilities for non-mappable devices (such as NAND flash)
+ * - permits private mappings, copies are taken of the data
+ */
+struct backing_dev_info mtd_bdi_unmappable = {
+ .capabilities = BDI_CAP_MAP_COPY,
+};
+
+/*
+ * backing device capabilities for R/O mappable devices (such as ROM)
+ * - permits private mappings, copies are taken of the data
+ * - permits non-writable shared mappings
+ */
+struct backing_dev_info mtd_bdi_ro_mappable = {
+ .capabilities = (BDI_CAP_MAP_COPY | BDI_CAP_MAP_DIRECT |
+ BDI_CAP_EXEC_MAP | BDI_CAP_READ_MAP),
+};
+
+/*
+ * backing device capabilities for writable mappable devices (such as RAM)
+ * - permits private mappings, copies are taken of the data
+ * - permits non-writable shared mappings
+ */
+struct backing_dev_info mtd_bdi_rw_mappable = {
+ .capabilities = (BDI_CAP_MAP_COPY | BDI_CAP_MAP_DIRECT |
+ BDI_CAP_EXEC_MAP | BDI_CAP_READ_MAP |
+ BDI_CAP_WRITE_MAP),
+};
+
+static int mtd_cls_suspend(struct device *dev, pm_message_t state);
+static int mtd_cls_resume(struct device *dev);
+
+static struct class mtd_class = {
+ .name = "mtd",
+ .owner = THIS_MODULE,
+ .suspend = mtd_cls_suspend,
+ .resume = mtd_cls_resume,
+};
+
+static DEFINE_IDR(mtd_idr);
/* 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);
+
+struct mtd_info *__mtd_next_device(int i)
+{
+ return idr_get_next(&mtd_idr, &i);
+}
+EXPORT_SYMBOL_GPL(__mtd_next_device);
static LIST_HEAD(mtd_notifiers);
+
+#if defined(CONFIG_MTD_CHAR) || defined(CONFIG_MTD_CHAR_MODULE)
+#define MTD_DEVT(index) MKDEV(MTD_CHAR_MAJOR, (index)*2)
+#else
+#define MTD_DEVT(index) 0
+#endif
+
+/* REVISIT once MTD uses the driver model better, whoever allocates
+ * the mtd_info will probably want to use the release() hook...
+ */
+static void mtd_release(struct device *dev)
+{
+ dev_t index = MTD_DEVT(dev_to_mtd(dev)->index);
+
+ /* remove /dev/mtdXro node if needed */
+ if (index)
+ device_destroy(&mtd_class, index + 1);
+}
+
+static int mtd_cls_suspend(struct device *dev, pm_message_t state)
+{
+ struct mtd_info *mtd = dev_to_mtd(dev);
+
+ if (mtd && mtd->suspend)
+ return mtd->suspend(mtd);
+ else
+ return 0;
+}
+
+static int mtd_cls_resume(struct device *dev)
+{
+ struct mtd_info *mtd = dev_to_mtd(dev);
+
+ if (mtd && mtd->resume)
+ mtd->resume(mtd);
+ return 0;
+}
+
+static ssize_t mtd_type_show(struct device *dev,
+ struct device_attribute *attr, char *buf)
+{
+ struct mtd_info *mtd = dev_to_mtd(dev);
+ char *type;
+
+ switch (mtd->type) {
+ case MTD_ABSENT:
+ type = "absent";
+ break;
+ case MTD_RAM:
+ type = "ram";
+ break;
+ case MTD_ROM:
+ type = "rom";
+ break;
+ case MTD_NORFLASH:
+ type = "nor";
+ break;
+ case MTD_NANDFLASH:
+ type = "nand";
+ break;
+ case MTD_DATAFLASH:
+ type = "dataflash";
+ break;
+ case MTD_UBIVOLUME:
+ type = "ubi";
+ break;
+ default:
+ type = "unknown";
+ }
+
+ return snprintf(buf, PAGE_SIZE, "%s\n", type);
+}
+static DEVICE_ATTR(type, S_IRUGO, mtd_type_show, NULL);
+
+static ssize_t mtd_flags_show(struct device *dev,
+ struct device_attribute *attr, char *buf)
+{
+ struct mtd_info *mtd = dev_to_mtd(dev);
+
+ return snprintf(buf, PAGE_SIZE, "0x%lx\n", (unsigned long)mtd->flags);
+
+}
+static DEVICE_ATTR(flags, S_IRUGO, mtd_flags_show, NULL);
+
+static ssize_t mtd_size_show(struct device *dev,
+ struct device_attribute *attr, char *buf)
+{
+ struct mtd_info *mtd = dev_to_mtd(dev);
+
+ return snprintf(buf, PAGE_SIZE, "%llu\n",
+ (unsigned long long)mtd->size);
+
+}
+static DEVICE_ATTR(size, S_IRUGO, mtd_size_show, NULL);
+
+static ssize_t mtd_erasesize_show(struct device *dev,
+ struct device_attribute *attr, char *buf)
+{
+ struct mtd_info *mtd = dev_to_mtd(dev);
+
+ return snprintf(buf, PAGE_SIZE, "%lu\n", (unsigned long)mtd->erasesize);
+
+}
+static DEVICE_ATTR(erasesize, S_IRUGO, mtd_erasesize_show, NULL);
+
+static ssize_t mtd_writesize_show(struct device *dev,
+ struct device_attribute *attr, char *buf)
+{
+ struct mtd_info *mtd = dev_to_mtd(dev);
+
+ return snprintf(buf, PAGE_SIZE, "%lu\n", (unsigned long)mtd->writesize);
+
+}
+static DEVICE_ATTR(writesize, S_IRUGO, mtd_writesize_show, NULL);
+
+static ssize_t mtd_subpagesize_show(struct device *dev,
+ struct device_attribute *attr, char *buf)
+{
+ struct mtd_info *mtd = dev_to_mtd(dev);
+ unsigned int subpagesize = mtd->writesize >> mtd->subpage_sft;
+
+ return snprintf(buf, PAGE_SIZE, "%u\n", subpagesize);
+
+}
+static DEVICE_ATTR(subpagesize, S_IRUGO, mtd_subpagesize_show, NULL);
+
+static ssize_t mtd_oobsize_show(struct device *dev,
+ struct device_attribute *attr, char *buf)
+{
+ struct mtd_info *mtd = dev_to_mtd(dev);
+
+ return snprintf(buf, PAGE_SIZE, "%lu\n", (unsigned long)mtd->oobsize);
+
+}
+static DEVICE_ATTR(oobsize, S_IRUGO, mtd_oobsize_show, NULL);
+
+static ssize_t mtd_numeraseregions_show(struct device *dev,
+ struct device_attribute *attr, char *buf)
+{
+ struct mtd_info *mtd = dev_to_mtd(dev);
+
+ return snprintf(buf, PAGE_SIZE, "%u\n", mtd->numeraseregions);
+
+}
+static DEVICE_ATTR(numeraseregions, S_IRUGO, mtd_numeraseregions_show,
+ NULL);
+
+static ssize_t mtd_name_show(struct device *dev,
+ struct device_attribute *attr, char *buf)
+{
+ struct mtd_info *mtd = dev_to_mtd(dev);
+
+ return snprintf(buf, PAGE_SIZE, "%s\n", mtd->name);
+
+}
+static DEVICE_ATTR(name, S_IRUGO, mtd_name_show, NULL);
+
+static struct attribute *mtd_attrs[] = {
+ &dev_attr_type.attr,
+ &dev_attr_flags.attr,
+ &dev_attr_size.attr,
+ &dev_attr_erasesize.attr,
+ &dev_attr_writesize.attr,
+ &dev_attr_subpagesize.attr,
+ &dev_attr_oobsize.attr,
+ &dev_attr_numeraseregions.attr,
+ &dev_attr_name.attr,
+ NULL,
+};
+
+static struct attribute_group mtd_group = {
+ .attrs = mtd_attrs,
+};
+
+static const struct attribute_group *mtd_groups[] = {
+ &mtd_group,
+ NULL,
+};
+
+static struct device_type mtd_devtype = {
+ .name = "mtd",
+ .groups = mtd_groups,
+ .release = mtd_release,
+};
+
/**
* add_mtd_device - register an MTD device
* @mtd: pointer to new MTD device info structure
* Add a device to the list of MTD devices present in the system, and
* notify each currently active MTD 'user' of its arrival. Returns
* zero on success or 1 on failure, which currently will only happen
- * if the number of present devices exceeds MAX_MTD_DEVICES (i.e. 16)
+ * if there is insufficient memory or a sysfs error.
*/
int add_mtd_device(struct mtd_info *mtd)
{
- int i;
+ struct mtd_notifier *not;
+ int i, error;
+
+ if (!mtd->backing_dev_info) {
+ switch (mtd->type) {
+ case MTD_RAM:
+ mtd->backing_dev_info = &mtd_bdi_rw_mappable;
+ break;
+ case MTD_ROM:
+ mtd->backing_dev_info = &mtd_bdi_ro_mappable;
+ break;
+ default:
+ mtd->backing_dev_info = &mtd_bdi_unmappable;
+ break;
+ }
+ }
BUG_ON(mtd->writesize == 0);
mutex_lock(&mtd_table_mutex);
- for (i=0; i < MAX_MTD_DEVICES; i++)
- if (!mtd_table[i]) {
- struct mtd_notifier *not;
-
- mtd_table[i] = mtd;
- mtd->index = i;
- mtd->usecount = 0;
-
- if (is_power_of_2(mtd->erasesize))
- mtd->erasesize_shift = ffs(mtd->erasesize) - 1;
- else
- mtd->erasesize_shift = 0;
-
- if (is_power_of_2(mtd->writesize))
- mtd->writesize_shift = ffs(mtd->writesize) - 1;
- else
- mtd->writesize_shift = 0;
-
- mtd->erasesize_mask = (1 << mtd->erasesize_shift) - 1;
- mtd->writesize_mask = (1 << mtd->writesize_shift) - 1;
-
- /* Some chips always power up locked. Unlock them now */
- if ((mtd->flags & MTD_WRITEABLE)
- && (mtd->flags & MTD_POWERUP_LOCK) && mtd->unlock) {
- if (mtd->unlock(mtd, 0, mtd->size))
- printk(KERN_WARNING
- "%s: unlock failed, "
- "writes may not work\n",
- mtd->name);
- }
+ do {
+ if (!idr_pre_get(&mtd_idr, GFP_KERNEL))
+ goto fail_locked;
+ error = idr_get_new(&mtd_idr, mtd, &i);
+ } while (error == -EAGAIN);
+
+ if (error)
+ goto fail_locked;
+
+ mtd->index = i;
+ mtd->usecount = 0;
+
+ if (is_power_of_2(mtd->erasesize))
+ mtd->erasesize_shift = ffs(mtd->erasesize) - 1;
+ else
+ mtd->erasesize_shift = 0;
+
+ if (is_power_of_2(mtd->writesize))
+ mtd->writesize_shift = ffs(mtd->writesize) - 1;
+ else
+ mtd->writesize_shift = 0;
+
+ mtd->erasesize_mask = (1 << mtd->erasesize_shift) - 1;
+ mtd->writesize_mask = (1 << mtd->writesize_shift) - 1;
+
+ /* Some chips always power up locked. Unlock them now */
+ if ((mtd->flags & MTD_WRITEABLE)
+ && (mtd->flags & MTD_POWERUP_LOCK) && mtd->unlock) {
+ if (mtd->unlock(mtd, 0, mtd->size))
+ printk(KERN_WARNING
+ "%s: unlock failed, writes may not work\n",
+ mtd->name);
+ }
- DEBUG(0, "mtd: Giving out device %d to %s\n",i, mtd->name);
- /* No need to get a refcount on the module containing
- the notifier, since we hold the mtd_table_mutex */
- list_for_each_entry(not, &mtd_notifiers, list)
- not->add(mtd);
-
- 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;
- }
+ /* Caller should have set dev.parent to match the
+ * physical device.
+ */
+ mtd->dev.type = &mtd_devtype;
+ mtd->dev.class = &mtd_class;
+ mtd->dev.devt = MTD_DEVT(i);
+ dev_set_name(&mtd->dev, "mtd%d", i);
+ dev_set_drvdata(&mtd->dev, mtd);
+ if (device_register(&mtd->dev) != 0)
+ goto fail_added;
+
+ if (MTD_DEVT(i))
+ device_create(&mtd_class, mtd->dev.parent,
+ MTD_DEVT(i) + 1,
+ NULL, "mtd%dro", i);
+
+ DEBUG(0, "mtd: Giving out device %d to %s\n", i, mtd->name);
+ /* No need to get a refcount on the module containing
+ the notifier, since we hold the mtd_table_mutex */
+ list_for_each_entry(not, &mtd_notifiers, list)
+ not->add(mtd);
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;
+
+fail_added:
+ idr_remove(&mtd_idr, i);
+fail_locked:
+ mutex_unlock(&mtd_table_mutex);
return 1;
}
int del_mtd_device (struct mtd_info *mtd)
{
int ret;
+ struct mtd_notifier *not;
mutex_lock(&mtd_table_mutex);
- if (mtd_table[mtd->index] != mtd) {
+ if (idr_find(&mtd_idr, mtd->index) != mtd) {
ret = -ENODEV;
- } else if (mtd->usecount) {
+ goto out_error;
+ }
+
+ /* No need to get a refcount on the module containing
+ the notifier, since we hold the mtd_table_mutex */
+ list_for_each_entry(not, &mtd_notifiers, list)
+ not->remove(mtd);
+
+ 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 mtd_notifier *not;
-
- /* No need to get a refcount on the module containing
- the notifier, since we hold the mtd_table_mutex */
- list_for_each_entry(not, &mtd_notifiers, list)
- not->remove(mtd);
+ device_unregister(&mtd->dev);
- mtd_table[mtd->index] = NULL;
+ idr_remove(&mtd_idr, mtd->index);
module_put(THIS_MODULE);
ret = 0;
}
+out_error:
mutex_unlock(&mtd_table_mutex);
return ret;
}
void register_mtd_user (struct mtd_notifier *new)
{
- int i;
+ struct mtd_info *mtd;
mutex_lock(&mtd_table_mutex);
__module_get(THIS_MODULE);
- for (i=0; i< MAX_MTD_DEVICES; i++)
- if (mtd_table[i])
- new->add(mtd_table[i]);
+ mtd_for_each_device(mtd)
+ new->add(mtd);
mutex_unlock(&mtd_table_mutex);
}
int unregister_mtd_user (struct mtd_notifier *old)
{
- int i;
+ struct mtd_info *mtd;
mutex_lock(&mtd_table_mutex);
module_put(THIS_MODULE);
- for (i=0; i< MAX_MTD_DEVICES; i++)
- if (mtd_table[i])
- old->remove(mtd_table[i]);
+ mtd_for_each_device(mtd)
+ old->remove(mtd);
list_del(&old->list);
mutex_unlock(&mtd_table_mutex);
struct mtd_info *get_mtd_device(struct mtd_info *mtd, int num)
{
- struct mtd_info *ret = NULL;
- int i, err = -ENODEV;
+ struct mtd_info *ret = NULL, *other;
+ int err = -ENODEV;
mutex_lock(&mtd_table_mutex);
if (num == -1) {
- for (i=0; i< MAX_MTD_DEVICES; i++)
- if (mtd_table[i] == mtd)
- ret = mtd_table[i];
- } else if (num < MAX_MTD_DEVICES) {
- ret = mtd_table[num];
+ mtd_for_each_device(other) {
+ if (other == mtd) {
+ ret = mtd;
+ break;
+ }
+ }
+ } else if (num >= 0) {
+ ret = idr_find(&mtd_idr, num);
if (mtd && mtd != ret)
ret = NULL;
}
- if (!ret)
- goto out_unlock;
-
- if (!try_module_get(ret->owner))
- goto out_unlock;
-
- if (ret->get_device) {
- err = ret->get_device(ret);
- if (err)
- goto out_put;
+ if (!ret) {
+ ret = ERR_PTR(err);
+ goto out;
}
- ret->usecount++;
+ err = __get_mtd_device(ret);
+ if (err)
+ ret = ERR_PTR(err);
+out:
mutex_unlock(&mtd_table_mutex);
return ret;
+}
-out_put:
- module_put(ret->owner);
-out_unlock:
- mutex_unlock(&mtd_table_mutex);
- return ERR_PTR(err);
+
+int __get_mtd_device(struct mtd_info *mtd)
+{
+ int err;
+
+ if (!try_module_get(mtd->owner))
+ return -ENODEV;
+
+ if (mtd->get_device) {
+
+ err = mtd->get_device(mtd);
+
+ if (err) {
+ module_put(mtd->owner);
+ return err;
+ }
+ }
+ mtd->usecount++;
+ return 0;
}
/**
struct mtd_info *get_mtd_device_nm(const char *name)
{
- int i, err = -ENODEV;
- struct mtd_info *mtd = NULL;
+ int err = -ENODEV;
+ struct mtd_info *mtd = NULL, *other;
mutex_lock(&mtd_table_mutex);
- for (i = 0; i < MAX_MTD_DEVICES; i++) {
- if (mtd_table[i] && !strcmp(name, mtd_table[i]->name)) {
- mtd = mtd_table[i];
+ mtd_for_each_device(other) {
+ if (!strcmp(name, other->name)) {
+ mtd = other;
break;
}
}
void put_mtd_device(struct mtd_info *mtd)
{
- int c;
-
mutex_lock(&mtd_table_mutex);
- c = --mtd->usecount;
+ __put_mtd_device(mtd);
+ mutex_unlock(&mtd_table_mutex);
+
+}
+
+void __put_mtd_device(struct mtd_info *mtd)
+{
+ --mtd->usecount;
+ BUG_ON(mtd->usecount < 0);
+
if (mtd->put_device)
mtd->put_device(mtd);
- mutex_unlock(&mtd_table_mutex);
- BUG_ON(c < 0);
module_put(mtd->owner);
}
EXPORT_SYMBOL_GPL(del_mtd_device);
EXPORT_SYMBOL_GPL(get_mtd_device);
EXPORT_SYMBOL_GPL(get_mtd_device_nm);
+EXPORT_SYMBOL_GPL(__get_mtd_device);
EXPORT_SYMBOL_GPL(put_mtd_device);
+EXPORT_SYMBOL_GPL(__put_mtd_device);
EXPORT_SYMBOL_GPL(register_mtd_user);
EXPORT_SYMBOL_GPL(unregister_mtd_user);
EXPORT_SYMBOL_GPL(default_mtd_writev);
static struct proc_dir_entry *proc_mtd;
-static inline int mtd_proc_info (char *buf, int i)
+static inline int mtd_proc_info(char *buf, struct mtd_info *this)
{
- struct mtd_info *this = mtd_table[i];
-
- if (!this)
- return 0;
-
- return sprintf(buf, "mtd%d: %8.8llx %8.8x \"%s\"\n", i,
+ return sprintf(buf, "mtd%d: %8.8llx %8.8x \"%s\"\n", this->index,
(unsigned long long)this->size,
this->erasesize, this->name);
}
static int mtd_read_proc (char *page, char **start, off_t off, int count,
int *eof, void *data_unused)
{
- int len, l, i;
+ struct mtd_info *mtd;
+ int len, l;
off_t begin = 0;
mutex_lock(&mtd_table_mutex);
len = sprintf(page, "dev: size erasesize name\n");
- for (i=0; i< MAX_MTD_DEVICES; i++) {
-
- l = mtd_proc_info(page + len, i);
+ mtd_for_each_device(mtd) {
+ l = mtd_proc_info(page + len, mtd);
len += l;
if (len+begin > off+count)
goto done;
return ((count < begin+len-off) ? count : begin+len-off);
}
+#endif /* CONFIG_PROC_FS */
+
/*====================================================================*/
/* Init code */
+static int __init mtd_bdi_init(struct backing_dev_info *bdi, const char *name)
+{
+ int ret;
+
+ ret = bdi_init(bdi);
+ if (!ret)
+ ret = bdi_register(bdi, NULL, name);
+
+ if (ret)
+ bdi_destroy(bdi);
+
+ return ret;
+}
+
static int __init init_mtd(void)
{
+ int ret;
+
+ ret = class_register(&mtd_class);
+ if (ret)
+ goto err_reg;
+
+ ret = mtd_bdi_init(&mtd_bdi_unmappable, "mtd-unmap");
+ if (ret)
+ goto err_bdi1;
+
+ ret = mtd_bdi_init(&mtd_bdi_ro_mappable, "mtd-romap");
+ if (ret)
+ goto err_bdi2;
+
+ ret = mtd_bdi_init(&mtd_bdi_rw_mappable, "mtd-rwmap");
+ if (ret)
+ goto err_bdi3;
+
+#ifdef CONFIG_PROC_FS
if ((proc_mtd = create_proc_entry( "mtd", 0, NULL )))
proc_mtd->read_proc = mtd_read_proc;
+#endif /* CONFIG_PROC_FS */
return 0;
+
+err_bdi3:
+ bdi_destroy(&mtd_bdi_ro_mappable);
+err_bdi2:
+ bdi_destroy(&mtd_bdi_unmappable);
+err_bdi1:
+ class_unregister(&mtd_class);
+err_reg:
+ pr_err("Error registering mtd class or bdi: %d\n", ret);
+ return ret;
}
static void __exit cleanup_mtd(void)
{
+#ifdef CONFIG_PROC_FS
if (proc_mtd)
remove_proc_entry( "mtd", NULL);
+#endif /* CONFIG_PROC_FS */
+ class_unregister(&mtd_class);
+ bdi_destroy(&mtd_bdi_unmappable);
+ bdi_destroy(&mtd_bdi_ro_mappable);
+ bdi_destroy(&mtd_bdi_rw_mappable);
}
module_init(init_mtd);
module_exit(cleanup_mtd);
-#endif /* CONFIG_PROC_FS */
-
-
MODULE_LICENSE("GPL");
MODULE_AUTHOR("David Woodhouse <dwmw2@infradead.org>");
MODULE_DESCRIPTION("Core MTD registration and access routines");
git://ftp.safe.ca / safe / jmp / linux-2.6 / blobdiff