#include <linux/module.h>
#include <linux/kernel.h>
#include <linux/ptrace.h>
+#include <linux/seq_file.h>
#include <linux/string.h>
#include <linux/timer.h>
#include <linux/major.h>
#include <linux/gfp.h>
#include <linux/mtd/mtd.h>
+#include <linux/mtd/partitions.h>
#include "mtdcore.h"
/*
* if the requested device does not appear to be present in the list.
*/
-int del_mtd_device (struct mtd_info *mtd)
+int del_mtd_device(struct mtd_info *mtd)
{
int ret;
struct mtd_notifier *not;
return ret;
}
+/**
+ * mtd_device_register - register an MTD device.
+ *
+ * @master: the MTD device to register
+ * @parts: the partitions to register - only valid if nr_parts > 0
+ * @nr_parts: the number of partitions in parts. If zero then the full MTD
+ * device is registered
+ *
+ * Register an MTD device with the system and optionally, a number of
+ * partitions. If nr_parts is 0 then the whole device is registered, otherwise
+ * only the partitions are registered. To register both the full device *and*
+ * the partitions, call mtd_device_register() twice, once with nr_parts == 0
+ * and once equal to the number of partitions.
+ */
+int mtd_device_register(struct mtd_info *master,
+ const struct mtd_partition *parts,
+ int nr_parts)
+{
+ return parts ? add_mtd_partitions(master, parts, nr_parts) :
+ add_mtd_device(master);
+}
+EXPORT_SYMBOL_GPL(mtd_device_register);
+
+/**
+ * mtd_device_unregister - unregister an existing MTD device.
+ *
+ * @master: the MTD device to unregister. This will unregister both the master
+ * and any partitions if registered.
+ */
+int mtd_device_unregister(struct mtd_info *master)
+{
+ int err;
+
+ err = del_mtd_partitions(master);
+ if (err)
+ return err;
+
+ if (!device_is_registered(&master->dev))
+ return 0;
+
+ return del_mtd_device(master);
+}
+EXPORT_SYMBOL_GPL(mtd_device_unregister);
+
/**
* register_mtd_user - register a 'user' of MTD devices.
* @new: pointer to notifier info structure
list_add(&new->list, &mtd_notifiers);
- __module_get(THIS_MODULE);
+ __module_get(THIS_MODULE);
mtd_for_each_device(mtd)
new->add(mtd);
return -ENODEV;
if (mtd->get_device) {
-
err = mtd->get_device(mtd);
if (err) {
if (!mtd)
goto out_unlock;
- if (!try_module_get(mtd->owner))
+ err = __get_mtd_device(mtd);
+ if (err)
goto out_unlock;
- if (mtd->get_device) {
- err = mtd->get_device(mtd);
- if (err)
- goto out_put;
- }
-
- mtd->usecount++;
mutex_unlock(&mtd_table_mutex);
return mtd;
-out_put:
- module_put(mtd->owner);
out_unlock:
mutex_unlock(&mtd_table_mutex);
return ERR_PTR(err);
return ret;
}
-EXPORT_SYMBOL_GPL(add_mtd_device);
-EXPORT_SYMBOL_GPL(del_mtd_device);
+/**
+ * mtd_kmalloc_up_to - allocate a contiguous buffer up to the specified size
+ * @size: A pointer to the ideal or maximum size of the allocation. Points
+ * to the actual allocation size on success.
+ *
+ * This routine attempts to allocate a contiguous kernel buffer up to
+ * the specified size, backing off the size of the request exponentially
+ * until the request succeeds or until the allocation size falls below
+ * the system page size. This attempts to make sure it does not adversely
+ * impact system performance, so when allocating more than one page, we
+ * ask the memory allocator to avoid re-trying, swapping, writing back
+ * or performing I/O.
+ *
+ * Note, this function also makes sure that the allocated buffer is aligned to
+ * the MTD device's min. I/O unit, i.e. the "mtd->writesize" value.
+ *
+ * This is called, for example by mtd_{read,write} and jffs2_scan_medium,
+ * to handle smaller (i.e. degraded) buffer allocations under low- or
+ * fragmented-memory situations where such reduced allocations, from a
+ * requested ideal, are allowed.
+ *
+ * Returns a pointer to the allocated buffer on success; otherwise, NULL.
+ */
+void *mtd_kmalloc_up_to(const struct mtd_info *mtd, size_t *size)
+{
+ gfp_t flags = __GFP_NOWARN | __GFP_WAIT |
+ __GFP_NORETRY | __GFP_NO_KSWAPD;
+ size_t min_alloc = max_t(size_t, mtd->writesize, PAGE_SIZE);
+ void *kbuf;
+
+ *size = min_t(size_t, *size, KMALLOC_MAX_SIZE);
+
+ while (*size > min_alloc) {
+ kbuf = kmalloc(*size, flags);
+ if (kbuf)
+ return kbuf;
+
+ *size >>= 1;
+ *size = ALIGN(*size, mtd->writesize);
+ }
+
+ /*
+ * For the last resort allocation allow 'kmalloc()' to do all sorts of
+ * things (write-back, dropping caches, etc) by using GFP_KERNEL.
+ */
+ return kmalloc(*size, GFP_KERNEL);
+}
+
EXPORT_SYMBOL_GPL(get_mtd_device);
EXPORT_SYMBOL_GPL(get_mtd_device_nm);
EXPORT_SYMBOL_GPL(__get_mtd_device);
EXPORT_SYMBOL_GPL(register_mtd_user);
EXPORT_SYMBOL_GPL(unregister_mtd_user);
EXPORT_SYMBOL_GPL(default_mtd_writev);
+EXPORT_SYMBOL_GPL(mtd_kmalloc_up_to);
#ifdef CONFIG_PROC_FS
static struct proc_dir_entry *proc_mtd;
-static inline int mtd_proc_info(char *buf, struct mtd_info *this)
-{
- 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)
+static int mtd_proc_show(struct seq_file *m, void *v)
{
struct mtd_info *mtd;
- int len, l;
- off_t begin = 0;
+ seq_puts(m, "dev: size erasesize name\n");
mutex_lock(&mtd_table_mutex);
-
- len = sprintf(page, "dev: size erasesize name\n");
mtd_for_each_device(mtd) {
- l = mtd_proc_info(page + len, mtd);
- len += l;
- if (len+begin > off+count)
- goto done;
- if (len+begin < off) {
- begin += len;
- len = 0;
- }
- }
-
- *eof = 1;
-
-done:
+ seq_printf(m, "mtd%d: %8.8llx %8.8x \"%s\"\n",
+ mtd->index, (unsigned long long)mtd->size,
+ mtd->erasesize, mtd->name);
+ }
mutex_unlock(&mtd_table_mutex);
- if (off >= len+begin)
- return 0;
- *start = page + (off-begin);
- return ((count < begin+len-off) ? count : begin+len-off);
+ return 0;
+}
+
+static int mtd_proc_open(struct inode *inode, struct file *file)
+{
+ return single_open(file, mtd_proc_show, NULL);
}
+static const struct file_operations mtd_proc_ops = {
+ .open = mtd_proc_open,
+ .read = seq_read,
+ .llseek = seq_lseek,
+ .release = single_release,
+};
#endif /* CONFIG_PROC_FS */
/*====================================================================*/
goto err_bdi3;
#ifdef CONFIG_PROC_FS
- if ((proc_mtd = create_proc_entry( "mtd", 0, NULL )))
- proc_mtd->read_proc = mtd_read_proc;
+ proc_mtd = proc_create("mtd", 0, NULL, &mtd_proc_ops);
#endif /* CONFIG_PROC_FS */
return 0;
static void __exit cleanup_mtd(void)
{
#ifdef CONFIG_PROC_FS
- if (proc_mtd)
+ if (proc_mtd)
remove_proc_entry( "mtd", NULL);
#endif /* CONFIG_PROC_FS */
class_unregister(&mtd_class);
git.openpandora.org / pandora-kernel.git / blobdiff