From 045e9a5d51ced27bfcbdb78071534ce6fd36b33d Mon Sep 17 00:00:00 2001 From: Nicolas Pitre Date: Tue, 8 Feb 2005 19:12:53 +0000 Subject: [PATCH] [MTD] Unabuse file-f_mode for OTP purpose Signed-off-by: Nicolas Pitre Signed-off-by: Thomas Gleixner --- drivers/mtd/mtdchar.c | 48 ++++++++++++++++++++++++------------------- 1 file changed, 27 insertions(+), 21 deletions(-) diff --git a/drivers/mtd/mtdchar.c b/drivers/mtd/mtdchar.c index 6ea2d8058a4..548b89204aa 100644 --- a/drivers/mtd/mtdchar.c +++ b/drivers/mtd/mtdchar.c @@ -1,5 +1,5 @@ /* - * $Id: mtdchar.c,v 1.67 2005/02/08 17:45:51 nico Exp $ + * $Id: mtdchar.c,v 1.68 2005/02/08 19:12:50 nico Exp $ * * Character-device access to raw MTD devices. * @@ -59,15 +59,25 @@ static inline void mtdchar_devfs_exit(void) #define mtdchar_devfs_exit() do { } while(0) #endif +/* + * We use file->private_data to store a pointer to the MTDdevice. + * Since alighment is at least 32 bits, we have 2 bits free for OTP + * modes as well. + */ + +#define TO_MTD(file) (struct mtd_info *)((long)((file)->private_data) & ~3L) -/* Well... let's abuse the unused bits in file->f_mode for those */ -#define MTD_MODE_OTP_FACT 0x1000 -#define MTD_MODE_OTP_USER 0x2000 -#define MTD_MODE_MASK 0xf000 +#define MTD_MODE_OTP_FACT 1 +#define MTD_MODE_OTP_USER 2 +#define MTD_MODE(file) ((long)((file)->private_data) & 3) + +#define SET_MTD_MODE(file, mode) \ + do { long __p = (long)((file)->private_data); \ + (file)->private_data = (void *)((__p & ~3L) | mode); } while (0) static loff_t mtd_lseek (struct file *file, loff_t offset, int orig) { - struct mtd_info *mtd = file->private_data; + struct mtd_info *mtd = TO_MTD(file); switch (orig) { case 0: @@ -111,10 +121,6 @@ static int mtd_open(struct inode *inode, struct file *file) if ((file->f_mode & 2) && (minor & 1)) return -EACCES; - /* make sure the locally abused bits are initialy clear */ - if (file->f_mode & MTD_MODE_MASK) - return -EWOULDBLOCK; - mtd = get_mtd_device(NULL, devnum); if (!mtd) @@ -144,7 +150,7 @@ static int mtd_close(struct inode *inode, struct file *file) DEBUG(MTD_DEBUG_LEVEL0, "MTD_close\n"); - mtd = file->private_data; + mtd = TO_MTD(file); if (mtd->sync) mtd->sync(mtd); @@ -161,7 +167,7 @@ static int mtd_close(struct inode *inode, struct file *file) static ssize_t mtd_read(struct file *file, char __user *buf, size_t count,loff_t *ppos) { - struct mtd_info *mtd = file->private_data; + struct mtd_info *mtd = TO_MTD(file); size_t retlen=0; size_t total_retlen=0; int ret=0; @@ -188,7 +194,7 @@ static ssize_t mtd_read(struct file *file, char __user *buf, size_t count,loff_t if (!kbuf) return -ENOMEM; - switch (file->f_mode & MTD_MODE_MASK) { + switch (MTD_MODE(file)) { case MTD_MODE_OTP_FACT: ret = mtd->read_fact_prot_reg(mtd, *ppos, len, &retlen, kbuf); break; @@ -231,7 +237,7 @@ static ssize_t mtd_read(struct file *file, char __user *buf, size_t count,loff_t static ssize_t mtd_write(struct file *file, const char __user *buf, size_t count,loff_t *ppos) { - struct mtd_info *mtd = file->private_data; + struct mtd_info *mtd = TO_MTD(file); char *kbuf; size_t retlen; size_t total_retlen=0; @@ -266,7 +272,7 @@ static ssize_t mtd_write(struct file *file, const char __user *buf, size_t count return -EFAULT; } - switch (file->f_mode & MTD_MODE_MASK) { + switch (MTD_MODE(file)) { case MTD_MODE_OTP_FACT: ret = -EROFS; break; @@ -310,7 +316,7 @@ static void mtdchar_erase_callback (struct erase_info *instr) static int mtd_ioctl(struct inode *inode, struct file *file, u_int cmd, u_long arg) { - struct mtd_info *mtd = file->private_data; + struct mtd_info *mtd = TO_MTD(file); void __user *argp = (void __user *)arg; int ret = 0; u_long size; @@ -558,19 +564,19 @@ static int mtd_ioctl(struct inode *inode, struct file *file, int mode; if (copy_from_user(&mode, argp, sizeof(int))) return -EFAULT; - file->f_mode &= ~MTD_MODE_MASK; + SET_MTD_MODE(file, 0); switch (mode) { case MTD_OTP_FACTORY: if (!mtd->read_fact_prot_reg) ret = -EOPNOTSUPP; else - file->f_mode |= MTD_MODE_OTP_FACT; + SET_MTD_MODE(file, MTD_MODE_OTP_FACT); break; case MTD_OTP_USER: if (!mtd->read_fact_prot_reg) ret = -EOPNOTSUPP; else - file->f_mode |= MTD_MODE_OTP_USER; + SET_MTD_MODE(file, MTD_MODE_OTP_USER); break; default: ret = -EINVAL; @@ -587,7 +593,7 @@ static int mtd_ioctl(struct inode *inode, struct file *file, if (!buf) return -ENOMEM; ret = -EOPNOTSUPP; - switch (file->f_mode & MTD_MODE_MASK) { + switch (MTD_MODE(file)) { case MTD_MODE_OTP_FACT: if (mtd->get_fact_prot_info) ret = mtd->get_fact_prot_info(mtd, buf, 4096); @@ -614,7 +620,7 @@ static int mtd_ioctl(struct inode *inode, struct file *file, { struct otp_info info; - if ((file->f_mode & MTD_MODE_MASK) != MTD_MODE_OTP_USER) + if (MTD_MODE(file) != MTD_MODE_OTP_USER) return -EINVAL; if (copy_from_user(&info, argp, sizeof(info))) return -EFAULT; -- 2.41.0