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path: root/drivers/mtd/mtdchar.c
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Diffstat (limited to 'drivers/mtd/mtdchar.c')
-rw-r--r--drivers/mtd/mtdchar.c124
1 files changed, 105 insertions, 19 deletions
diff --git a/drivers/mtd/mtdchar.c b/drivers/mtd/mtdchar.c
index 5b081cb8435..000d65ea55a 100644
--- a/drivers/mtd/mtdchar.c
+++ b/drivers/mtd/mtdchar.c
@@ -15,12 +15,15 @@
#include <linux/smp_lock.h>
#include <linux/backing-dev.h>
#include <linux/compat.h>
+#include <linux/mount.h>
#include <linux/mtd/mtd.h>
#include <linux/mtd/compatmac.h>
#include <asm/uaccess.h>
+#define MTD_INODE_FS_MAGIC 0x11307854
+static struct vfsmount *mtd_inode_mnt __read_mostly;
/*
* Data structure to hold the pointer to the mtd device as well
@@ -28,6 +31,7 @@
*/
struct mtd_file_info {
struct mtd_info *mtd;
+ struct inode *ino;
enum mtd_file_modes mode;
};
@@ -64,12 +68,10 @@ static int mtd_open(struct inode *inode, struct file *file)
int ret = 0;
struct mtd_info *mtd;
struct mtd_file_info *mfi;
+ struct inode *mtd_ino;
DEBUG(MTD_DEBUG_LEVEL0, "MTD_open\n");
- if (devnum >= MAX_MTD_DEVICES)
- return -ENODEV;
-
/* You can't open the RO devices RW */
if ((file->f_mode & FMODE_WRITE) && (minor & 1))
return -EACCES;
@@ -88,11 +90,23 @@ static int mtd_open(struct inode *inode, struct file *file)
goto out;
}
- if (mtd->backing_dev_info)
- file->f_mapping->backing_dev_info = mtd->backing_dev_info;
+ mtd_ino = iget_locked(mtd_inode_mnt->mnt_sb, devnum);
+ if (!mtd_ino) {
+ put_mtd_device(mtd);
+ ret = -ENOMEM;
+ goto out;
+ }
+ if (mtd_ino->i_state & I_NEW) {
+ mtd_ino->i_private = mtd;
+ mtd_ino->i_mode = S_IFCHR;
+ mtd_ino->i_data.backing_dev_info = mtd->backing_dev_info;
+ unlock_new_inode(mtd_ino);
+ }
+ file->f_mapping = mtd_ino->i_mapping;
/* You can't open it RW if it's not a writeable device */
if ((file->f_mode & FMODE_WRITE) && !(mtd->flags & MTD_WRITEABLE)) {
+ iput(mtd_ino);
put_mtd_device(mtd);
ret = -EACCES;
goto out;
@@ -100,10 +114,12 @@ static int mtd_open(struct inode *inode, struct file *file)
mfi = kzalloc(sizeof(*mfi), GFP_KERNEL);
if (!mfi) {
+ iput(mtd_ino);
put_mtd_device(mtd);
ret = -ENOMEM;
goto out;
}
+ mfi->ino = mtd_ino;
mfi->mtd = mtd;
file->private_data = mfi;
@@ -125,6 +141,8 @@ static int mtd_close(struct inode *inode, struct file *file)
if ((file->f_mode & FMODE_WRITE) && mtd->sync)
mtd->sync(mtd);
+ iput(mfi->ino);
+
put_mtd_device(mtd);
file->private_data = NULL;
kfree(mfi);
@@ -373,7 +391,7 @@ static int mtd_do_writeoob(struct file *file, struct mtd_info *mtd,
if (!mtd->write_oob)
ret = -EOPNOTSUPP;
else
- ret = access_ok(VERIFY_READ, ptr, length) ? 0 : EFAULT;
+ ret = access_ok(VERIFY_READ, ptr, length) ? 0 : -EFAULT;
if (ret)
return ret;
@@ -450,8 +468,7 @@ static int mtd_do_readoob(struct mtd_info *mtd, uint64_t start,
return ret;
}
-static int mtd_ioctl(struct inode *inode, struct file *file,
- u_int cmd, u_long arg)
+static int mtd_ioctl(struct file *file, u_int cmd, u_long arg)
{
struct mtd_file_info *mfi = file->private_data;
struct mtd_info *mtd = mfi->mtd;
@@ -482,7 +499,7 @@ static int mtd_ioctl(struct inode *inode, struct file *file,
{
uint32_t ur_idx;
struct mtd_erase_region_info *kr;
- struct region_info_user *ur = (struct region_info_user *) argp;
+ struct region_info_user __user *ur = argp;
if (get_user(ur_idx, &(ur->regionindex)))
return -EFAULT;
@@ -822,6 +839,17 @@ static int mtd_ioctl(struct inode *inode, struct file *file,
return ret;
} /* memory_ioctl */
+static long mtd_unlocked_ioctl(struct file *file, u_int cmd, u_long arg)
+{
+ int ret;
+
+ lock_kernel();
+ ret = mtd_ioctl(file, cmd, arg);
+ unlock_kernel();
+
+ return ret;
+}
+
#ifdef CONFIG_COMPAT
struct mtd_oob_buf32 {
@@ -836,7 +864,6 @@ struct mtd_oob_buf32 {
static long mtd_compat_ioctl(struct file *file, unsigned int cmd,
unsigned long arg)
{
- struct inode *inode = file->f_path.dentry->d_inode;
struct mtd_file_info *mfi = file->private_data;
struct mtd_info *mtd = mfi->mtd;
void __user *argp = compat_ptr(arg);
@@ -874,7 +901,7 @@ static long mtd_compat_ioctl(struct file *file, unsigned int cmd,
break;
}
default:
- ret = mtd_ioctl(inode, file, cmd, (unsigned long)argp);
+ ret = mtd_ioctl(file, cmd, (unsigned long)argp);
}
unlock_kernel();
@@ -942,7 +969,7 @@ static const struct file_operations mtd_fops = {
.llseek = mtd_lseek,
.read = mtd_read,
.write = mtd_write,
- .ioctl = mtd_ioctl,
+ .unlocked_ioctl = mtd_unlocked_ioctl,
#ifdef CONFIG_COMPAT
.compat_ioctl = mtd_compat_ioctl,
#endif
@@ -954,22 +981,81 @@ static const struct file_operations mtd_fops = {
#endif
};
+static int mtd_inodefs_get_sb(struct file_system_type *fs_type, int flags,
+ const char *dev_name, void *data,
+ struct vfsmount *mnt)
+{
+ return get_sb_pseudo(fs_type, "mtd_inode:", NULL, MTD_INODE_FS_MAGIC,
+ mnt);
+}
+
+static struct file_system_type mtd_inodefs_type = {
+ .name = "mtd_inodefs",
+ .get_sb = mtd_inodefs_get_sb,
+ .kill_sb = kill_anon_super,
+};
+
+static void mtdchar_notify_add(struct mtd_info *mtd)
+{
+}
+
+static void mtdchar_notify_remove(struct mtd_info *mtd)
+{
+ struct inode *mtd_ino = ilookup(mtd_inode_mnt->mnt_sb, mtd->index);
+
+ if (mtd_ino) {
+ /* Destroy the inode if it exists */
+ mtd_ino->i_nlink = 0;
+ iput(mtd_ino);
+ }
+}
+
+static struct mtd_notifier mtdchar_notifier = {
+ .add = mtdchar_notify_add,
+ .remove = mtdchar_notify_remove,
+};
+
static int __init init_mtdchar(void)
{
- int status;
+ int ret;
- status = register_chrdev(MTD_CHAR_MAJOR, "mtd", &mtd_fops);
- if (status < 0) {
- printk(KERN_NOTICE "Can't allocate major number %d for Memory Technology Devices.\n",
- MTD_CHAR_MAJOR);
+ ret = __register_chrdev(MTD_CHAR_MAJOR, 0, 1 << MINORBITS,
+ "mtd", &mtd_fops);
+ if (ret < 0) {
+ pr_notice("Can't allocate major number %d for "
+ "Memory Technology Devices.\n", MTD_CHAR_MAJOR);
+ return ret;
}
- return status;
+ ret = register_filesystem(&mtd_inodefs_type);
+ if (ret) {
+ pr_notice("Can't register mtd_inodefs filesystem: %d\n", ret);
+ goto err_unregister_chdev;
+ }
+
+ mtd_inode_mnt = kern_mount(&mtd_inodefs_type);
+ if (IS_ERR(mtd_inode_mnt)) {
+ ret = PTR_ERR(mtd_inode_mnt);
+ pr_notice("Error mounting mtd_inodefs filesystem: %d\n", ret);
+ goto err_unregister_filesystem;
+ }
+ register_mtd_user(&mtdchar_notifier);
+
+ return ret;
+
+err_unregister_filesystem:
+ unregister_filesystem(&mtd_inodefs_type);
+err_unregister_chdev:
+ __unregister_chrdev(MTD_CHAR_MAJOR, 0, 1 << MINORBITS, "mtd");
+ return ret;
}
static void __exit cleanup_mtdchar(void)
{
- unregister_chrdev(MTD_CHAR_MAJOR, "mtd");
+ unregister_mtd_user(&mtdchar_notifier);
+ mntput(mtd_inode_mnt);
+ unregister_filesystem(&mtd_inodefs_type);
+ __unregister_chrdev(MTD_CHAR_MAJOR, 0, 1 << MINORBITS, "mtd");
}
module_init(init_mtdchar);
generated by cgit v1.2.3-70-g09d2 (git 2.46.0) at 2024-12-02 05:59:37 +0000