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authorDaniel Baumann <daniel.baumann@progress-linux.org>2024-04-07 18:49:45 +0000
committerDaniel Baumann <daniel.baumann@progress-linux.org>2024-04-07 18:49:45 +0000
commit2c3c1048746a4622d8c89a29670120dc8fab93c4 (patch)
tree848558de17fb3008cdf4d861b01ac7781903ce39 /drivers/mtd/mtdchar.c
parentInitial commit. (diff)
downloadlinux-2c3c1048746a4622d8c89a29670120dc8fab93c4.tar.xz
linux-2c3c1048746a4622d8c89a29670120dc8fab93c4.zip
Adding upstream version 6.1.76.upstream/6.1.76
Signed-off-by: Daniel Baumann <daniel.baumann@progress-linux.org>
Diffstat (limited to 'drivers/mtd/mtdchar.c')
-rw-r--r--drivers/mtd/mtdchar.c1439
1 files changed, 1439 insertions, 0 deletions
diff --git a/drivers/mtd/mtdchar.c b/drivers/mtd/mtdchar.c
new file mode 100644
index 000000000..8dc4f5c49
--- /dev/null
+++ b/drivers/mtd/mtdchar.c
@@ -0,0 +1,1439 @@
+// SPDX-License-Identifier: GPL-2.0-or-later
+/*
+ * Copyright © 1999-2010 David Woodhouse <dwmw2@infradead.org>
+ */
+
+#include <linux/device.h>
+#include <linux/fs.h>
+#include <linux/mm.h>
+#include <linux/err.h>
+#include <linux/init.h>
+#include <linux/kernel.h>
+#include <linux/module.h>
+#include <linux/slab.h>
+#include <linux/sched.h>
+#include <linux/mutex.h>
+#include <linux/backing-dev.h>
+#include <linux/compat.h>
+#include <linux/mount.h>
+#include <linux/blkpg.h>
+#include <linux/magic.h>
+#include <linux/major.h>
+#include <linux/mtd/mtd.h>
+#include <linux/mtd/partitions.h>
+#include <linux/mtd/map.h>
+
+#include <linux/uaccess.h>
+
+#include "mtdcore.h"
+
+/*
+ * Data structure to hold the pointer to the mtd device as well
+ * as mode information of various use cases.
+ */
+struct mtd_file_info {
+ struct mtd_info *mtd;
+ enum mtd_file_modes mode;
+};
+
+static loff_t mtdchar_lseek(struct file *file, loff_t offset, int orig)
+{
+ struct mtd_file_info *mfi = file->private_data;
+ return fixed_size_llseek(file, offset, orig, mfi->mtd->size);
+}
+
+static int mtdchar_open(struct inode *inode, struct file *file)
+{
+ int minor = iminor(inode);
+ int devnum = minor >> 1;
+ int ret = 0;
+ struct mtd_info *mtd;
+ struct mtd_file_info *mfi;
+
+ pr_debug("MTD_open\n");
+
+ /* You can't open the RO devices RW */
+ if ((file->f_mode & FMODE_WRITE) && (minor & 1))
+ return -EACCES;
+
+ mtd = get_mtd_device(NULL, devnum);
+
+ if (IS_ERR(mtd))
+ return PTR_ERR(mtd);
+
+ if (mtd->type == MTD_ABSENT) {
+ ret = -ENODEV;
+ goto out1;
+ }
+
+ /* You can't open it RW if it's not a writeable device */
+ if ((file->f_mode & FMODE_WRITE) && !(mtd->flags & MTD_WRITEABLE)) {
+ ret = -EACCES;
+ goto out1;
+ }
+
+ mfi = kzalloc(sizeof(*mfi), GFP_KERNEL);
+ if (!mfi) {
+ ret = -ENOMEM;
+ goto out1;
+ }
+ mfi->mtd = mtd;
+ file->private_data = mfi;
+ return 0;
+
+out1:
+ put_mtd_device(mtd);
+ return ret;
+} /* mtdchar_open */
+
+/*====================================================================*/
+
+static int mtdchar_close(struct inode *inode, struct file *file)
+{
+ struct mtd_file_info *mfi = file->private_data;
+ struct mtd_info *mtd = mfi->mtd;
+
+ pr_debug("MTD_close\n");
+
+ /* Only sync if opened RW */
+ if ((file->f_mode & FMODE_WRITE))
+ mtd_sync(mtd);
+
+ put_mtd_device(mtd);
+ file->private_data = NULL;
+ kfree(mfi);
+
+ return 0;
+} /* mtdchar_close */
+
+/* Back in June 2001, dwmw2 wrote:
+ *
+ * FIXME: This _really_ needs to die. In 2.5, we should lock the
+ * userspace buffer down and use it directly with readv/writev.
+ *
+ * The implementation below, using mtd_kmalloc_up_to, mitigates
+ * allocation failures when the system is under low-memory situations
+ * or if memory is highly fragmented at the cost of reducing the
+ * performance of the requested transfer due to a smaller buffer size.
+ *
+ * A more complex but more memory-efficient implementation based on
+ * get_user_pages and iovecs to cover extents of those pages is a
+ * longer-term goal, as intimated by dwmw2 above. However, for the
+ * write case, this requires yet more complex head and tail transfer
+ * handling when those head and tail offsets and sizes are such that
+ * alignment requirements are not met in the NAND subdriver.
+ */
+
+static ssize_t mtdchar_read(struct file *file, char __user *buf, size_t count,
+ loff_t *ppos)
+{
+ struct mtd_file_info *mfi = file->private_data;
+ struct mtd_info *mtd = mfi->mtd;
+ size_t retlen;
+ size_t total_retlen=0;
+ int ret=0;
+ int len;
+ size_t size = count;
+ char *kbuf;
+
+ pr_debug("MTD_read\n");
+
+ if (*ppos + count > mtd->size) {
+ if (*ppos < mtd->size)
+ count = mtd->size - *ppos;
+ else
+ count = 0;
+ }
+
+ if (!count)
+ return 0;
+
+ kbuf = mtd_kmalloc_up_to(mtd, &size);
+ if (!kbuf)
+ return -ENOMEM;
+
+ while (count) {
+ len = min_t(size_t, count, size);
+
+ switch (mfi->mode) {
+ case MTD_FILE_MODE_OTP_FACTORY:
+ ret = mtd_read_fact_prot_reg(mtd, *ppos, len,
+ &retlen, kbuf);
+ break;
+ case MTD_FILE_MODE_OTP_USER:
+ ret = mtd_read_user_prot_reg(mtd, *ppos, len,
+ &retlen, kbuf);
+ break;
+ case MTD_FILE_MODE_RAW:
+ {
+ struct mtd_oob_ops ops = {};
+
+ ops.mode = MTD_OPS_RAW;
+ ops.datbuf = kbuf;
+ ops.oobbuf = NULL;
+ ops.len = len;
+
+ ret = mtd_read_oob(mtd, *ppos, &ops);
+ retlen = ops.retlen;
+ break;
+ }
+ default:
+ ret = mtd_read(mtd, *ppos, len, &retlen, kbuf);
+ }
+ /* Nand returns -EBADMSG on ECC errors, but it returns
+ * the data. For our userspace tools it is important
+ * to dump areas with ECC errors!
+ * For kernel internal usage it also might return -EUCLEAN
+ * to signal the caller that a bitflip has occurred and has
+ * been corrected by the ECC algorithm.
+ * Userspace software which accesses NAND this way
+ * must be aware of the fact that it deals with NAND
+ */
+ if (!ret || mtd_is_bitflip_or_eccerr(ret)) {
+ *ppos += retlen;
+ if (copy_to_user(buf, kbuf, retlen)) {
+ kfree(kbuf);
+ return -EFAULT;
+ }
+ else
+ total_retlen += retlen;
+
+ count -= retlen;
+ buf += retlen;
+ if (retlen == 0)
+ count = 0;
+ }
+ else {
+ kfree(kbuf);
+ return ret;
+ }
+
+ }
+
+ kfree(kbuf);
+ return total_retlen;
+} /* mtdchar_read */
+
+static ssize_t mtdchar_write(struct file *file, const char __user *buf, size_t count,
+ loff_t *ppos)
+{
+ struct mtd_file_info *mfi = file->private_data;
+ struct mtd_info *mtd = mfi->mtd;
+ size_t size = count;
+ char *kbuf;
+ size_t retlen;
+ size_t total_retlen=0;
+ int ret=0;
+ int len;
+
+ pr_debug("MTD_write\n");
+
+ if (*ppos >= mtd->size)
+ return -ENOSPC;
+
+ if (*ppos + count > mtd->size)
+ count = mtd->size - *ppos;
+
+ if (!count)
+ return 0;
+
+ kbuf = mtd_kmalloc_up_to(mtd, &size);
+ if (!kbuf)
+ return -ENOMEM;
+
+ while (count) {
+ len = min_t(size_t, count, size);
+
+ if (copy_from_user(kbuf, buf, len)) {
+ kfree(kbuf);
+ return -EFAULT;
+ }
+
+ switch (mfi->mode) {
+ case MTD_FILE_MODE_OTP_FACTORY:
+ ret = -EROFS;
+ break;
+ case MTD_FILE_MODE_OTP_USER:
+ ret = mtd_write_user_prot_reg(mtd, *ppos, len,
+ &retlen, kbuf);
+ break;
+
+ case MTD_FILE_MODE_RAW:
+ {
+ struct mtd_oob_ops ops = {};
+
+ ops.mode = MTD_OPS_RAW;
+ ops.datbuf = kbuf;
+ ops.oobbuf = NULL;
+ ops.ooboffs = 0;
+ ops.len = len;
+
+ ret = mtd_write_oob(mtd, *ppos, &ops);
+ retlen = ops.retlen;
+ break;
+ }
+
+ default:
+ ret = mtd_write(mtd, *ppos, len, &retlen, kbuf);
+ }
+
+ /*
+ * Return -ENOSPC only if no data could be written at all.
+ * Otherwise just return the number of bytes that actually
+ * have been written.
+ */
+ if ((ret == -ENOSPC) && (total_retlen))
+ break;
+
+ if (!ret) {
+ *ppos += retlen;
+ total_retlen += retlen;
+ count -= retlen;
+ buf += retlen;
+ }
+ else {
+ kfree(kbuf);
+ return ret;
+ }
+ }
+
+ kfree(kbuf);
+ return total_retlen;
+} /* mtdchar_write */
+
+/*======================================================================
+
+ IOCTL calls for getting device parameters.
+
+======================================================================*/
+
+static int otp_select_filemode(struct mtd_file_info *mfi, int mode)
+{
+ struct mtd_info *mtd = mfi->mtd;
+ size_t retlen;
+
+ switch (mode) {
+ case MTD_OTP_FACTORY:
+ if (mtd_read_fact_prot_reg(mtd, -1, 0, &retlen, NULL) ==
+ -EOPNOTSUPP)
+ return -EOPNOTSUPP;
+
+ mfi->mode = MTD_FILE_MODE_OTP_FACTORY;
+ break;
+ case MTD_OTP_USER:
+ if (mtd_read_user_prot_reg(mtd, -1, 0, &retlen, NULL) ==
+ -EOPNOTSUPP)
+ return -EOPNOTSUPP;
+
+ mfi->mode = MTD_FILE_MODE_OTP_USER;
+ break;
+ case MTD_OTP_OFF:
+ mfi->mode = MTD_FILE_MODE_NORMAL;
+ break;
+ default:
+ return -EINVAL;
+ }
+
+ return 0;
+}
+
+static int mtdchar_writeoob(struct file *file, struct mtd_info *mtd,
+ uint64_t start, uint32_t length, void __user *ptr,
+ uint32_t __user *retp)
+{
+ struct mtd_info *master = mtd_get_master(mtd);
+ struct mtd_file_info *mfi = file->private_data;
+ struct mtd_oob_ops ops = {};
+ uint32_t retlen;
+ int ret = 0;
+
+ if (length > 4096)
+ return -EINVAL;
+
+ if (!master->_write_oob)
+ return -EOPNOTSUPP;
+
+ ops.ooblen = length;
+ ops.ooboffs = start & (mtd->writesize - 1);
+ ops.datbuf = NULL;
+ ops.mode = (mfi->mode == MTD_FILE_MODE_RAW) ? MTD_OPS_RAW :
+ MTD_OPS_PLACE_OOB;
+
+ if (ops.ooboffs && ops.ooblen > (mtd->oobsize - ops.ooboffs))
+ return -EINVAL;
+
+ ops.oobbuf = memdup_user(ptr, length);
+ if (IS_ERR(ops.oobbuf))
+ return PTR_ERR(ops.oobbuf);
+
+ start &= ~((uint64_t)mtd->writesize - 1);
+ ret = mtd_write_oob(mtd, start, &ops);
+
+ if (ops.oobretlen > 0xFFFFFFFFU)
+ ret = -EOVERFLOW;
+ retlen = ops.oobretlen;
+ if (copy_to_user(retp, &retlen, sizeof(length)))
+ ret = -EFAULT;
+
+ kfree(ops.oobbuf);
+ return ret;
+}
+
+static int mtdchar_readoob(struct file *file, struct mtd_info *mtd,
+ uint64_t start, uint32_t length, void __user *ptr,
+ uint32_t __user *retp)
+{
+ struct mtd_file_info *mfi = file->private_data;
+ struct mtd_oob_ops ops = {};
+ int ret = 0;
+
+ if (length > 4096)
+ return -EINVAL;
+
+ ops.ooblen = length;
+ ops.ooboffs = start & (mtd->writesize - 1);
+ ops.datbuf = NULL;
+ ops.mode = (mfi->mode == MTD_FILE_MODE_RAW) ? MTD_OPS_RAW :
+ MTD_OPS_PLACE_OOB;
+
+ if (ops.ooboffs && ops.ooblen > (mtd->oobsize - ops.ooboffs))
+ return -EINVAL;
+
+ ops.oobbuf = kmalloc(length, GFP_KERNEL);
+ if (!ops.oobbuf)
+ return -ENOMEM;
+
+ start &= ~((uint64_t)mtd->writesize - 1);
+ ret = mtd_read_oob(mtd, start, &ops);
+
+ if (put_user(ops.oobretlen, retp))
+ ret = -EFAULT;
+ else if (ops.oobretlen && copy_to_user(ptr, ops.oobbuf,
+ ops.oobretlen))
+ ret = -EFAULT;
+
+ kfree(ops.oobbuf);
+
+ /*
+ * NAND returns -EBADMSG on ECC errors, but it returns the OOB
+ * data. For our userspace tools it is important to dump areas
+ * with ECC errors!
+ * For kernel internal usage it also might return -EUCLEAN
+ * to signal the caller that a bitflip has occurred and has
+ * been corrected by the ECC algorithm.
+ *
+ * Note: currently the standard NAND function, nand_read_oob_std,
+ * does not calculate ECC for the OOB area, so do not rely on
+ * this behavior unless you have replaced it with your own.
+ */
+ if (mtd_is_bitflip_or_eccerr(ret))
+ return 0;
+
+ return ret;
+}
+
+/*
+ * Copies (and truncates, if necessary) OOB layout information to the
+ * deprecated layout struct, nand_ecclayout_user. This is necessary only to
+ * support the deprecated API ioctl ECCGETLAYOUT while allowing all new
+ * functionality to use mtd_ooblayout_ops flexibly (i.e. mtd_ooblayout_ops
+ * can describe any kind of OOB layout with almost zero overhead from a
+ * memory usage point of view).
+ */
+static int shrink_ecclayout(struct mtd_info *mtd,
+ struct nand_ecclayout_user *to)
+{
+ struct mtd_oob_region oobregion;
+ int i, section = 0, ret;
+
+ if (!mtd || !to)
+ return -EINVAL;
+
+ memset(to, 0, sizeof(*to));
+
+ to->eccbytes = 0;
+ for (i = 0; i < MTD_MAX_ECCPOS_ENTRIES;) {
+ u32 eccpos;
+
+ ret = mtd_ooblayout_ecc(mtd, section++, &oobregion);
+ if (ret < 0) {
+ if (ret != -ERANGE)
+ return ret;
+
+ break;
+ }
+
+ eccpos = oobregion.offset;
+ for (; i < MTD_MAX_ECCPOS_ENTRIES &&
+ eccpos < oobregion.offset + oobregion.length; i++) {
+ to->eccpos[i] = eccpos++;
+ to->eccbytes++;
+ }
+ }
+
+ for (i = 0; i < MTD_MAX_OOBFREE_ENTRIES; i++) {
+ ret = mtd_ooblayout_free(mtd, i, &oobregion);
+ if (ret < 0) {
+ if (ret != -ERANGE)
+ return ret;
+
+ break;
+ }
+
+ to->oobfree[i].offset = oobregion.offset;
+ to->oobfree[i].length = oobregion.length;
+ to->oobavail += to->oobfree[i].length;
+ }
+
+ return 0;
+}
+
+static int get_oobinfo(struct mtd_info *mtd, struct nand_oobinfo *to)
+{
+ struct mtd_oob_region oobregion;
+ int i, section = 0, ret;
+
+ if (!mtd || !to)
+ return -EINVAL;
+
+ memset(to, 0, sizeof(*to));
+
+ to->eccbytes = 0;
+ for (i = 0; i < ARRAY_SIZE(to->eccpos);) {
+ u32 eccpos;
+
+ ret = mtd_ooblayout_ecc(mtd, section++, &oobregion);
+ if (ret < 0) {
+ if (ret != -ERANGE)
+ return ret;
+
+ break;
+ }
+
+ if (oobregion.length + i > ARRAY_SIZE(to->eccpos))
+ return -EINVAL;
+
+ eccpos = oobregion.offset;
+ for (; eccpos < oobregion.offset + oobregion.length; i++) {
+ to->eccpos[i] = eccpos++;
+ to->eccbytes++;
+ }
+ }
+
+ for (i = 0; i < 8; i++) {
+ ret = mtd_ooblayout_free(mtd, i, &oobregion);
+ if (ret < 0) {
+ if (ret != -ERANGE)
+ return ret;
+
+ break;
+ }
+
+ to->oobfree[i][0] = oobregion.offset;
+ to->oobfree[i][1] = oobregion.length;
+ }
+
+ to->useecc = MTD_NANDECC_AUTOPLACE;
+
+ return 0;
+}
+
+static int mtdchar_blkpg_ioctl(struct mtd_info *mtd,
+ struct blkpg_ioctl_arg *arg)
+{
+ struct blkpg_partition p;
+
+ if (!capable(CAP_SYS_ADMIN))
+ return -EPERM;
+
+ if (copy_from_user(&p, arg->data, sizeof(p)))
+ return -EFAULT;
+
+ switch (arg->op) {
+ case BLKPG_ADD_PARTITION:
+
+ /* Only master mtd device must be used to add partitions */
+ if (mtd_is_partition(mtd))
+ return -EINVAL;
+
+ /* Sanitize user input */
+ p.devname[BLKPG_DEVNAMELTH - 1] = '\0';
+
+ return mtd_add_partition(mtd, p.devname, p.start, p.length);
+
+ case BLKPG_DEL_PARTITION:
+
+ if (p.pno < 0)
+ return -EINVAL;
+
+ return mtd_del_partition(mtd, p.pno);
+
+ default:
+ return -EINVAL;
+ }
+}
+
+static void adjust_oob_length(struct mtd_info *mtd, uint64_t start,
+ struct mtd_oob_ops *ops)
+{
+ uint32_t start_page, end_page;
+ u32 oob_per_page;
+
+ if (ops->len == 0 || ops->ooblen == 0)
+ return;
+
+ start_page = mtd_div_by_ws(start, mtd);
+ end_page = mtd_div_by_ws(start + ops->len - 1, mtd);
+ oob_per_page = mtd_oobavail(mtd, ops);
+
+ ops->ooblen = min_t(size_t, ops->ooblen,
+ (end_page - start_page + 1) * oob_per_page);
+}
+
+static noinline_for_stack int
+mtdchar_write_ioctl(struct mtd_info *mtd, struct mtd_write_req __user *argp)
+{
+ struct mtd_info *master = mtd_get_master(mtd);
+ struct mtd_write_req req;
+ const void __user *usr_data, *usr_oob;
+ uint8_t *datbuf = NULL, *oobbuf = NULL;
+ size_t datbuf_len, oobbuf_len;
+ int ret = 0;
+
+ if (copy_from_user(&req, argp, sizeof(req)))
+ return -EFAULT;
+
+ usr_data = (const void __user *)(uintptr_t)req.usr_data;
+ usr_oob = (const void __user *)(uintptr_t)req.usr_oob;
+
+ if (!master->_write_oob)
+ return -EOPNOTSUPP;
+
+ if (!usr_data)
+ req.len = 0;
+
+ if (!usr_oob)
+ req.ooblen = 0;
+
+ req.len &= 0xffffffff;
+ req.ooblen &= 0xffffffff;
+
+ if (req.start + req.len > mtd->size)
+ return -EINVAL;
+
+ datbuf_len = min_t(size_t, req.len, mtd->erasesize);
+ if (datbuf_len > 0) {
+ datbuf = kvmalloc(datbuf_len, GFP_KERNEL);
+ if (!datbuf)
+ return -ENOMEM;
+ }
+
+ oobbuf_len = min_t(size_t, req.ooblen, mtd->erasesize);
+ if (oobbuf_len > 0) {
+ oobbuf = kvmalloc(oobbuf_len, GFP_KERNEL);
+ if (!oobbuf) {
+ kvfree(datbuf);
+ return -ENOMEM;
+ }
+ }
+
+ while (req.len > 0 || (!usr_data && req.ooblen > 0)) {
+ struct mtd_oob_ops ops = {
+ .mode = req.mode,
+ .len = min_t(size_t, req.len, datbuf_len),
+ .ooblen = min_t(size_t, req.ooblen, oobbuf_len),
+ .datbuf = datbuf,
+ .oobbuf = oobbuf,
+ };
+
+ /*
+ * Shorten non-page-aligned, eraseblock-sized writes so that
+ * the write ends on an eraseblock boundary. This is necessary
+ * for adjust_oob_length() to properly handle non-page-aligned
+ * writes.
+ */
+ if (ops.len == mtd->erasesize)
+ ops.len -= mtd_mod_by_ws(req.start + ops.len, mtd);
+
+ /*
+ * For writes which are not OOB-only, adjust the amount of OOB
+ * data written according to the number of data pages written.
+ * This is necessary to prevent OOB data from being skipped
+ * over in data+OOB writes requiring multiple mtd_write_oob()
+ * calls to be completed.
+ */
+ adjust_oob_length(mtd, req.start, &ops);
+
+ if (copy_from_user(datbuf, usr_data, ops.len) ||
+ copy_from_user(oobbuf, usr_oob, ops.ooblen)) {
+ ret = -EFAULT;
+ break;
+ }
+
+ ret = mtd_write_oob(mtd, req.start, &ops);
+ if (ret)
+ break;
+
+ req.start += ops.retlen;
+ req.len -= ops.retlen;
+ usr_data += ops.retlen;
+
+ req.ooblen -= ops.oobretlen;
+ usr_oob += ops.oobretlen;
+ }
+
+ kvfree(datbuf);
+ kvfree(oobbuf);
+
+ return ret;
+}
+
+static noinline_for_stack int
+mtdchar_read_ioctl(struct mtd_info *mtd, struct mtd_read_req __user *argp)
+{
+ struct mtd_info *master = mtd_get_master(mtd);
+ struct mtd_read_req req;
+ void __user *usr_data, *usr_oob;
+ uint8_t *datbuf = NULL, *oobbuf = NULL;
+ size_t datbuf_len, oobbuf_len;
+ size_t orig_len, orig_ooblen;
+ int ret = 0;
+
+ if (copy_from_user(&req, argp, sizeof(req)))
+ return -EFAULT;
+
+ orig_len = req.len;
+ orig_ooblen = req.ooblen;
+
+ usr_data = (void __user *)(uintptr_t)req.usr_data;
+ usr_oob = (void __user *)(uintptr_t)req.usr_oob;
+
+ if (!master->_read_oob)
+ return -EOPNOTSUPP;
+
+ if (!usr_data)
+ req.len = 0;
+
+ if (!usr_oob)
+ req.ooblen = 0;
+
+ req.ecc_stats.uncorrectable_errors = 0;
+ req.ecc_stats.corrected_bitflips = 0;
+ req.ecc_stats.max_bitflips = 0;
+
+ req.len &= 0xffffffff;
+ req.ooblen &= 0xffffffff;
+
+ if (req.start + req.len > mtd->size) {
+ ret = -EINVAL;
+ goto out;
+ }
+
+ datbuf_len = min_t(size_t, req.len, mtd->erasesize);
+ if (datbuf_len > 0) {
+ datbuf = kvmalloc(datbuf_len, GFP_KERNEL);
+ if (!datbuf) {
+ ret = -ENOMEM;
+ goto out;
+ }
+ }
+
+ oobbuf_len = min_t(size_t, req.ooblen, mtd->erasesize);
+ if (oobbuf_len > 0) {
+ oobbuf = kvmalloc(oobbuf_len, GFP_KERNEL);
+ if (!oobbuf) {
+ ret = -ENOMEM;
+ goto out;
+ }
+ }
+
+ while (req.len > 0 || (!usr_data && req.ooblen > 0)) {
+ struct mtd_req_stats stats;
+ struct mtd_oob_ops ops = {
+ .mode = req.mode,
+ .len = min_t(size_t, req.len, datbuf_len),
+ .ooblen = min_t(size_t, req.ooblen, oobbuf_len),
+ .datbuf = datbuf,
+ .oobbuf = oobbuf,
+ .stats = &stats,
+ };
+
+ /*
+ * Shorten non-page-aligned, eraseblock-sized reads so that the
+ * read ends on an eraseblock boundary. This is necessary in
+ * order to prevent OOB data for some pages from being
+ * duplicated in the output of non-page-aligned reads requiring
+ * multiple mtd_read_oob() calls to be completed.
+ */
+ if (ops.len == mtd->erasesize)
+ ops.len -= mtd_mod_by_ws(req.start + ops.len, mtd);
+
+ ret = mtd_read_oob(mtd, (loff_t)req.start, &ops);
+
+ req.ecc_stats.uncorrectable_errors +=
+ stats.uncorrectable_errors;
+ req.ecc_stats.corrected_bitflips += stats.corrected_bitflips;
+ req.ecc_stats.max_bitflips =
+ max(req.ecc_stats.max_bitflips, stats.max_bitflips);
+
+ if (ret && !mtd_is_bitflip_or_eccerr(ret))
+ break;
+
+ if (copy_to_user(usr_data, ops.datbuf, ops.retlen) ||
+ copy_to_user(usr_oob, ops.oobbuf, ops.oobretlen)) {
+ ret = -EFAULT;
+ break;
+ }
+
+ req.start += ops.retlen;
+ req.len -= ops.retlen;
+ usr_data += ops.retlen;
+
+ req.ooblen -= ops.oobretlen;
+ usr_oob += ops.oobretlen;
+ }
+
+ /*
+ * As multiple iterations of the above loop (and therefore multiple
+ * mtd_read_oob() calls) may be necessary to complete the read request,
+ * adjust the final return code to ensure it accounts for all detected
+ * ECC errors.
+ */
+ if (!ret || mtd_is_bitflip(ret)) {
+ if (req.ecc_stats.uncorrectable_errors > 0)
+ ret = -EBADMSG;
+ else if (req.ecc_stats.corrected_bitflips > 0)
+ ret = -EUCLEAN;
+ }
+
+out:
+ req.len = orig_len - req.len;
+ req.ooblen = orig_ooblen - req.ooblen;
+
+ if (copy_to_user(argp, &req, sizeof(req)))
+ ret = -EFAULT;
+
+ kvfree(datbuf);
+ kvfree(oobbuf);
+
+ return ret;
+}
+
+static int mtdchar_ioctl(struct file *file, u_int cmd, u_long arg)
+{
+ struct mtd_file_info *mfi = file->private_data;
+ struct mtd_info *mtd = mfi->mtd;
+ struct mtd_info *master = mtd_get_master(mtd);
+ void __user *argp = (void __user *)arg;
+ int ret = 0;
+ struct mtd_info_user info;
+
+ pr_debug("MTD_ioctl\n");
+
+ /*
+ * Check the file mode to require "dangerous" commands to have write
+ * permissions.
+ */
+ switch (cmd) {
+ /* "safe" commands */
+ case MEMGETREGIONCOUNT:
+ case MEMGETREGIONINFO:
+ case MEMGETINFO:
+ case MEMREADOOB:
+ case MEMREADOOB64:
+ case MEMREAD:
+ case MEMISLOCKED:
+ case MEMGETOOBSEL:
+ case MEMGETBADBLOCK:
+ case OTPSELECT:
+ case OTPGETREGIONCOUNT:
+ case OTPGETREGIONINFO:
+ case ECCGETLAYOUT:
+ case ECCGETSTATS:
+ case MTDFILEMODE:
+ case BLKPG:
+ case BLKRRPART:
+ break;
+
+ /* "dangerous" commands */
+ case MEMERASE:
+ case MEMERASE64:
+ case MEMLOCK:
+ case MEMUNLOCK:
+ case MEMSETBADBLOCK:
+ case MEMWRITEOOB:
+ case MEMWRITEOOB64:
+ case MEMWRITE:
+ case OTPLOCK:
+ case OTPERASE:
+ if (!(file->f_mode & FMODE_WRITE))
+ return -EPERM;
+ break;
+
+ default:
+ return -ENOTTY;
+ }
+
+ switch (cmd) {
+ case MEMGETREGIONCOUNT:
+ if (copy_to_user(argp, &(mtd->numeraseregions), sizeof(int)))
+ return -EFAULT;
+ break;
+
+ case MEMGETREGIONINFO:
+ {
+ uint32_t ur_idx;
+ struct mtd_erase_region_info *kr;
+ struct region_info_user __user *ur = argp;
+
+ if (get_user(ur_idx, &(ur->regionindex)))
+ return -EFAULT;
+
+ if (ur_idx >= mtd->numeraseregions)
+ return -EINVAL;
+
+ kr = &(mtd->eraseregions[ur_idx]);
+
+ if (put_user(kr->offset, &(ur->offset))
+ || put_user(kr->erasesize, &(ur->erasesize))
+ || put_user(kr->numblocks, &(ur->numblocks)))
+ return -EFAULT;
+
+ break;
+ }
+
+ case MEMGETINFO:
+ memset(&info, 0, sizeof(info));
+ info.type = mtd->type;
+ info.flags = mtd->flags;
+ info.size = mtd->size;
+ info.erasesize = mtd->erasesize;
+ info.writesize = mtd->writesize;
+ info.oobsize = mtd->oobsize;
+ /* The below field is obsolete */
+ info.padding = 0;
+ if (copy_to_user(argp, &info, sizeof(struct mtd_info_user)))
+ return -EFAULT;
+ break;
+
+ case MEMERASE:
+ case MEMERASE64:
+ {
+ struct erase_info *erase;
+
+ erase=kzalloc(sizeof(struct erase_info),GFP_KERNEL);
+ if (!erase)
+ ret = -ENOMEM;
+ else {
+ if (cmd == MEMERASE64) {
+ struct erase_info_user64 einfo64;
+
+ if (copy_from_user(&einfo64, argp,
+ sizeof(struct erase_info_user64))) {
+ kfree(erase);
+ return -EFAULT;
+ }
+ erase->addr = einfo64.start;
+ erase->len = einfo64.length;
+ } else {
+ struct erase_info_user einfo32;
+
+ if (copy_from_user(&einfo32, argp,
+ sizeof(struct erase_info_user))) {
+ kfree(erase);
+ return -EFAULT;
+ }
+ erase->addr = einfo32.start;
+ erase->len = einfo32.length;
+ }
+
+ ret = mtd_erase(mtd, erase);
+ kfree(erase);
+ }
+ break;
+ }
+
+ case MEMWRITEOOB:
+ {
+ struct mtd_oob_buf buf;
+ struct mtd_oob_buf __user *buf_user = argp;
+
+ /* NOTE: writes return length to buf_user->length */
+ if (copy_from_user(&buf, argp, sizeof(buf)))
+ ret = -EFAULT;
+ else
+ ret = mtdchar_writeoob(file, mtd, buf.start, buf.length,
+ buf.ptr, &buf_user->length);
+ break;
+ }
+
+ case MEMREADOOB:
+ {
+ struct mtd_oob_buf buf;
+ struct mtd_oob_buf __user *buf_user = argp;
+
+ /* NOTE: writes return length to buf_user->start */
+ if (copy_from_user(&buf, argp, sizeof(buf)))
+ ret = -EFAULT;
+ else
+ ret = mtdchar_readoob(file, mtd, buf.start, buf.length,
+ buf.ptr, &buf_user->start);
+ break;
+ }
+
+ case MEMWRITEOOB64:
+ {
+ struct mtd_oob_buf64 buf;
+ struct mtd_oob_buf64 __user *buf_user = argp;
+
+ if (copy_from_user(&buf, argp, sizeof(buf)))
+ ret = -EFAULT;
+ else
+ ret = mtdchar_writeoob(file, mtd, buf.start, buf.length,
+ (void __user *)(uintptr_t)buf.usr_ptr,
+ &buf_user->length);
+ break;
+ }
+
+ case MEMREADOOB64:
+ {
+ struct mtd_oob_buf64 buf;
+ struct mtd_oob_buf64 __user *buf_user = argp;
+
+ if (copy_from_user(&buf, argp, sizeof(buf)))
+ ret = -EFAULT;
+ else
+ ret = mtdchar_readoob(file, mtd, buf.start, buf.length,
+ (void __user *)(uintptr_t)buf.usr_ptr,
+ &buf_user->length);
+ break;
+ }
+
+ case MEMWRITE:
+ {
+ ret = mtdchar_write_ioctl(mtd,
+ (struct mtd_write_req __user *)arg);
+ break;
+ }
+
+ case MEMREAD:
+ {
+ ret = mtdchar_read_ioctl(mtd,
+ (struct mtd_read_req __user *)arg);
+ break;
+ }
+
+ case MEMLOCK:
+ {
+ struct erase_info_user einfo;
+
+ if (copy_from_user(&einfo, argp, sizeof(einfo)))
+ return -EFAULT;
+
+ ret = mtd_lock(mtd, einfo.start, einfo.length);
+ break;
+ }
+
+ case MEMUNLOCK:
+ {
+ struct erase_info_user einfo;
+
+ if (copy_from_user(&einfo, argp, sizeof(einfo)))
+ return -EFAULT;
+
+ ret = mtd_unlock(mtd, einfo.start, einfo.length);
+ break;
+ }
+
+ case MEMISLOCKED:
+ {
+ struct erase_info_user einfo;
+
+ if (copy_from_user(&einfo, argp, sizeof(einfo)))
+ return -EFAULT;
+
+ ret = mtd_is_locked(mtd, einfo.start, einfo.length);
+ break;
+ }
+
+ /* Legacy interface */
+ case MEMGETOOBSEL:
+ {
+ struct nand_oobinfo oi;
+
+ if (!master->ooblayout)
+ return -EOPNOTSUPP;
+
+ ret = get_oobinfo(mtd, &oi);
+ if (ret)
+ return ret;
+
+ if (copy_to_user(argp, &oi, sizeof(struct nand_oobinfo)))
+ return -EFAULT;
+ break;
+ }
+
+ case MEMGETBADBLOCK:
+ {
+ loff_t offs;
+
+ if (copy_from_user(&offs, argp, sizeof(loff_t)))
+ return -EFAULT;
+ return mtd_block_isbad(mtd, offs);
+ }
+
+ case MEMSETBADBLOCK:
+ {
+ loff_t offs;
+
+ if (copy_from_user(&offs, argp, sizeof(loff_t)))
+ return -EFAULT;
+ return mtd_block_markbad(mtd, offs);
+ }
+
+ case OTPSELECT:
+ {
+ int mode;
+ if (copy_from_user(&mode, argp, sizeof(int)))
+ return -EFAULT;
+
+ mfi->mode = MTD_FILE_MODE_NORMAL;
+
+ ret = otp_select_filemode(mfi, mode);
+
+ file->f_pos = 0;
+ break;
+ }
+
+ case OTPGETREGIONCOUNT:
+ case OTPGETREGIONINFO:
+ {
+ struct otp_info *buf = kmalloc(4096, GFP_KERNEL);
+ size_t retlen;
+ if (!buf)
+ return -ENOMEM;
+ switch (mfi->mode) {
+ case MTD_FILE_MODE_OTP_FACTORY:
+ ret = mtd_get_fact_prot_info(mtd, 4096, &retlen, buf);
+ break;
+ case MTD_FILE_MODE_OTP_USER:
+ ret = mtd_get_user_prot_info(mtd, 4096, &retlen, buf);
+ break;
+ default:
+ ret = -EINVAL;
+ break;
+ }
+ if (!ret) {
+ if (cmd == OTPGETREGIONCOUNT) {
+ int nbr = retlen / sizeof(struct otp_info);
+ ret = copy_to_user(argp, &nbr, sizeof(int));
+ } else
+ ret = copy_to_user(argp, buf, retlen);
+ if (ret)
+ ret = -EFAULT;
+ }
+ kfree(buf);
+ break;
+ }
+
+ case OTPLOCK:
+ case OTPERASE:
+ {
+ struct otp_info oinfo;
+
+ if (mfi->mode != MTD_FILE_MODE_OTP_USER)
+ return -EINVAL;
+ if (copy_from_user(&oinfo, argp, sizeof(oinfo)))
+ return -EFAULT;
+ if (cmd == OTPLOCK)
+ ret = mtd_lock_user_prot_reg(mtd, oinfo.start, oinfo.length);
+ else
+ ret = mtd_erase_user_prot_reg(mtd, oinfo.start, oinfo.length);
+ break;
+ }
+
+ /* This ioctl is being deprecated - it truncates the ECC layout */
+ case ECCGETLAYOUT:
+ {
+ struct nand_ecclayout_user *usrlay;
+
+ if (!master->ooblayout)
+ return -EOPNOTSUPP;
+
+ usrlay = kmalloc(sizeof(*usrlay), GFP_KERNEL);
+ if (!usrlay)
+ return -ENOMEM;
+
+ shrink_ecclayout(mtd, usrlay);
+
+ if (copy_to_user(argp, usrlay, sizeof(*usrlay)))
+ ret = -EFAULT;
+ kfree(usrlay);
+ break;
+ }
+
+ case ECCGETSTATS:
+ {
+ if (copy_to_user(argp, &mtd->ecc_stats,
+ sizeof(struct mtd_ecc_stats)))
+ return -EFAULT;
+ break;
+ }
+
+ case MTDFILEMODE:
+ {
+ mfi->mode = 0;
+
+ switch(arg) {
+ case MTD_FILE_MODE_OTP_FACTORY:
+ case MTD_FILE_MODE_OTP_USER:
+ ret = otp_select_filemode(mfi, arg);
+ break;
+
+ case MTD_FILE_MODE_RAW:
+ if (!mtd_has_oob(mtd))
+ return -EOPNOTSUPP;
+ mfi->mode = arg;
+ break;
+
+ case MTD_FILE_MODE_NORMAL:
+ break;
+ default:
+ ret = -EINVAL;
+ }
+ file->f_pos = 0;
+ break;
+ }
+
+ case BLKPG:
+ {
+ struct blkpg_ioctl_arg __user *blk_arg = argp;
+ struct blkpg_ioctl_arg a;
+
+ if (copy_from_user(&a, blk_arg, sizeof(a)))
+ ret = -EFAULT;
+ else
+ ret = mtdchar_blkpg_ioctl(mtd, &a);
+ break;
+ }
+
+ case BLKRRPART:
+ {
+ /* No reread partition feature. Just return ok */
+ ret = 0;
+ break;
+ }
+ }
+
+ return ret;
+} /* memory_ioctl */
+
+static long mtdchar_unlocked_ioctl(struct file *file, u_int cmd, u_long arg)
+{
+ struct mtd_file_info *mfi = file->private_data;
+ struct mtd_info *mtd = mfi->mtd;
+ struct mtd_info *master = mtd_get_master(mtd);
+ int ret;
+
+ mutex_lock(&master->master.chrdev_lock);
+ ret = mtdchar_ioctl(file, cmd, arg);
+ mutex_unlock(&master->master.chrdev_lock);
+
+ return ret;
+}
+
+#ifdef CONFIG_COMPAT
+
+struct mtd_oob_buf32 {
+ u_int32_t start;
+ u_int32_t length;
+ compat_caddr_t ptr; /* unsigned char* */
+};
+
+#define MEMWRITEOOB32 _IOWR('M', 3, struct mtd_oob_buf32)
+#define MEMREADOOB32 _IOWR('M', 4, struct mtd_oob_buf32)
+
+static long mtdchar_compat_ioctl(struct file *file, unsigned int cmd,
+ unsigned long arg)
+{
+ struct mtd_file_info *mfi = file->private_data;
+ struct mtd_info *mtd = mfi->mtd;
+ struct mtd_info *master = mtd_get_master(mtd);
+ void __user *argp = compat_ptr(arg);
+ int ret = 0;
+
+ mutex_lock(&master->master.chrdev_lock);
+
+ switch (cmd) {
+ case MEMWRITEOOB32:
+ {
+ struct mtd_oob_buf32 buf;
+ struct mtd_oob_buf32 __user *buf_user = argp;
+
+ if (!(file->f_mode & FMODE_WRITE)) {
+ ret = -EPERM;
+ break;
+ }
+
+ if (copy_from_user(&buf, argp, sizeof(buf)))
+ ret = -EFAULT;
+ else
+ ret = mtdchar_writeoob(file, mtd, buf.start,
+ buf.length, compat_ptr(buf.ptr),
+ &buf_user->length);
+ break;
+ }
+
+ case MEMREADOOB32:
+ {
+ struct mtd_oob_buf32 buf;
+ struct mtd_oob_buf32 __user *buf_user = argp;
+
+ /* NOTE: writes return length to buf->start */
+ if (copy_from_user(&buf, argp, sizeof(buf)))
+ ret = -EFAULT;
+ else
+ ret = mtdchar_readoob(file, mtd, buf.start,
+ buf.length, compat_ptr(buf.ptr),
+ &buf_user->start);
+ break;
+ }
+
+ case BLKPG:
+ {
+ /* Convert from blkpg_compat_ioctl_arg to blkpg_ioctl_arg */
+ struct blkpg_compat_ioctl_arg __user *uarg = argp;
+ struct blkpg_compat_ioctl_arg compat_arg;
+ struct blkpg_ioctl_arg a;
+
+ if (copy_from_user(&compat_arg, uarg, sizeof(compat_arg))) {
+ ret = -EFAULT;
+ break;
+ }
+
+ memset(&a, 0, sizeof(a));
+ a.op = compat_arg.op;
+ a.flags = compat_arg.flags;
+ a.datalen = compat_arg.datalen;
+ a.data = compat_ptr(compat_arg.data);
+
+ ret = mtdchar_blkpg_ioctl(mtd, &a);
+ break;
+ }
+
+ default:
+ ret = mtdchar_ioctl(file, cmd, (unsigned long)argp);
+ }
+
+ mutex_unlock(&master->master.chrdev_lock);
+
+ return ret;
+}
+
+#endif /* CONFIG_COMPAT */
+
+/*
+ * try to determine where a shared mapping can be made
+ * - only supported for NOMMU at the moment (MMU can't doesn't copy private
+ * mappings)
+ */
+#ifndef CONFIG_MMU
+static unsigned long mtdchar_get_unmapped_area(struct file *file,
+ unsigned long addr,
+ unsigned long len,
+ unsigned long pgoff,
+ unsigned long flags)
+{
+ struct mtd_file_info *mfi = file->private_data;
+ struct mtd_info *mtd = mfi->mtd;
+ unsigned long offset;
+ int ret;
+
+ if (addr != 0)
+ return (unsigned long) -EINVAL;
+
+ if (len > mtd->size || pgoff >= (mtd->size >> PAGE_SHIFT))
+ return (unsigned long) -EINVAL;
+
+ offset = pgoff << PAGE_SHIFT;
+ if (offset > mtd->size - len)
+ return (unsigned long) -EINVAL;
+
+ ret = mtd_get_unmapped_area(mtd, len, offset, flags);
+ return ret == -EOPNOTSUPP ? -ENODEV : ret;
+}
+
+static unsigned mtdchar_mmap_capabilities(struct file *file)
+{
+ struct mtd_file_info *mfi = file->private_data;
+
+ return mtd_mmap_capabilities(mfi->mtd);
+}
+#endif
+
+/*
+ * set up a mapping for shared memory segments
+ */
+static int mtdchar_mmap(struct file *file, struct vm_area_struct *vma)
+{
+#ifdef CONFIG_MMU
+ struct mtd_file_info *mfi = file->private_data;
+ struct mtd_info *mtd = mfi->mtd;
+ struct map_info *map = mtd->priv;
+
+ /* This is broken because it assumes the MTD device is map-based
+ and that mtd->priv is a valid struct map_info. It should be
+ replaced with something that uses the mtd_get_unmapped_area()
+ operation properly. */
+ if (0 /*mtd->type == MTD_RAM || mtd->type == MTD_ROM*/) {
+#ifdef pgprot_noncached
+ if (file->f_flags & O_DSYNC || map->phys >= __pa(high_memory))
+ vma->vm_page_prot = pgprot_noncached(vma->vm_page_prot);
+#endif
+ return vm_iomap_memory(vma, map->phys, map->size);
+ }
+ return -ENODEV;
+#else
+ return vma->vm_flags & VM_SHARED ? 0 : -EACCES;
+#endif
+}
+
+static const struct file_operations mtd_fops = {
+ .owner = THIS_MODULE,
+ .llseek = mtdchar_lseek,
+ .read = mtdchar_read,
+ .write = mtdchar_write,
+ .unlocked_ioctl = mtdchar_unlocked_ioctl,
+#ifdef CONFIG_COMPAT
+ .compat_ioctl = mtdchar_compat_ioctl,
+#endif
+ .open = mtdchar_open,
+ .release = mtdchar_close,
+ .mmap = mtdchar_mmap,
+#ifndef CONFIG_MMU
+ .get_unmapped_area = mtdchar_get_unmapped_area,
+ .mmap_capabilities = mtdchar_mmap_capabilities,
+#endif
+};
+
+int __init init_mtdchar(void)
+{
+ int ret;
+
+ ret = __register_chrdev(MTD_CHAR_MAJOR, 0, 1 << MINORBITS,
+ "mtd", &mtd_fops);
+ if (ret < 0) {
+ pr_err("Can't allocate major number %d for MTD\n",
+ MTD_CHAR_MAJOR);
+ return ret;
+ }
+
+ return ret;
+}
+
+void __exit cleanup_mtdchar(void)
+{
+ __unregister_chrdev(MTD_CHAR_MAJOR, 0, 1 << MINORBITS, "mtd");
+}
+
+MODULE_ALIAS_CHARDEV_MAJOR(MTD_CHAR_MAJOR);