mirror of
https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git
synced 2024-08-27 11:19:37 +00:00
![Chengguang Xu](/assets/img/avatar_default.png)
Change error code to -ENOMEM from -EIO because the error is related to memory allocating. Signed-off-by: Chengguang Xu <cgxu519@gmail.com> Message-Id: <1557066367-4783-2-git-send-email-cgxu519@gmail.com> Signed-off-by: Max Filippov <jcmvbkbc@gmail.com>
371 lines
8.2 KiB
C
371 lines
8.2 KiB
C
/*
|
|
* arch/xtensa/platforms/iss/simdisk.c
|
|
*
|
|
* This file is subject to the terms and conditions of the GNU General Public
|
|
* License. See the file "COPYING" in the main directory of this archive
|
|
* for more details.
|
|
*
|
|
* Copyright (C) 2001-2013 Tensilica Inc.
|
|
* Authors Victor Prupis
|
|
*/
|
|
|
|
#include <linux/module.h>
|
|
#include <linux/moduleparam.h>
|
|
#include <linux/kernel.h>
|
|
#include <linux/init.h>
|
|
#include <linux/string.h>
|
|
#include <linux/blkdev.h>
|
|
#include <linux/bio.h>
|
|
#include <linux/proc_fs.h>
|
|
#include <linux/uaccess.h>
|
|
#include <platform/simcall.h>
|
|
|
|
#define SIMDISK_MAJOR 240
|
|
#define SIMDISK_MINORS 1
|
|
#define MAX_SIMDISK_COUNT 10
|
|
|
|
struct simdisk {
|
|
const char *filename;
|
|
spinlock_t lock;
|
|
struct request_queue *queue;
|
|
struct gendisk *gd;
|
|
struct proc_dir_entry *procfile;
|
|
int users;
|
|
unsigned long size;
|
|
int fd;
|
|
};
|
|
|
|
|
|
static int simdisk_count = CONFIG_BLK_DEV_SIMDISK_COUNT;
|
|
module_param(simdisk_count, int, S_IRUGO);
|
|
MODULE_PARM_DESC(simdisk_count, "Number of simdisk units.");
|
|
|
|
static int n_files;
|
|
static const char *filename[MAX_SIMDISK_COUNT] = {
|
|
#ifdef CONFIG_SIMDISK0_FILENAME
|
|
CONFIG_SIMDISK0_FILENAME,
|
|
#ifdef CONFIG_SIMDISK1_FILENAME
|
|
CONFIG_SIMDISK1_FILENAME,
|
|
#endif
|
|
#endif
|
|
};
|
|
|
|
static int simdisk_param_set_filename(const char *val,
|
|
const struct kernel_param *kp)
|
|
{
|
|
if (n_files < ARRAY_SIZE(filename))
|
|
filename[n_files++] = val;
|
|
else
|
|
return -EINVAL;
|
|
return 0;
|
|
}
|
|
|
|
static const struct kernel_param_ops simdisk_param_ops_filename = {
|
|
.set = simdisk_param_set_filename,
|
|
};
|
|
module_param_cb(filename, &simdisk_param_ops_filename, &n_files, 0);
|
|
MODULE_PARM_DESC(filename, "Backing storage filename.");
|
|
|
|
static int simdisk_major = SIMDISK_MAJOR;
|
|
|
|
static void simdisk_transfer(struct simdisk *dev, unsigned long sector,
|
|
unsigned long nsect, char *buffer, int write)
|
|
{
|
|
unsigned long offset = sector << SECTOR_SHIFT;
|
|
unsigned long nbytes = nsect << SECTOR_SHIFT;
|
|
|
|
if (offset > dev->size || dev->size - offset < nbytes) {
|
|
pr_notice("Beyond-end %s (%ld %ld)\n",
|
|
write ? "write" : "read", offset, nbytes);
|
|
return;
|
|
}
|
|
|
|
spin_lock(&dev->lock);
|
|
while (nbytes > 0) {
|
|
unsigned long io;
|
|
|
|
simc_lseek(dev->fd, offset, SEEK_SET);
|
|
READ_ONCE(*buffer);
|
|
if (write)
|
|
io = simc_write(dev->fd, buffer, nbytes);
|
|
else
|
|
io = simc_read(dev->fd, buffer, nbytes);
|
|
if (io == -1) {
|
|
pr_err("SIMDISK: IO error %d\n", errno);
|
|
break;
|
|
}
|
|
buffer += io;
|
|
offset += io;
|
|
nbytes -= io;
|
|
}
|
|
spin_unlock(&dev->lock);
|
|
}
|
|
|
|
static blk_qc_t simdisk_make_request(struct request_queue *q, struct bio *bio)
|
|
{
|
|
struct simdisk *dev = q->queuedata;
|
|
struct bio_vec bvec;
|
|
struct bvec_iter iter;
|
|
sector_t sector = bio->bi_iter.bi_sector;
|
|
|
|
bio_for_each_segment(bvec, bio, iter) {
|
|
char *buffer = kmap_atomic(bvec.bv_page) + bvec.bv_offset;
|
|
unsigned len = bvec.bv_len >> SECTOR_SHIFT;
|
|
|
|
simdisk_transfer(dev, sector, len, buffer,
|
|
bio_data_dir(bio) == WRITE);
|
|
sector += len;
|
|
kunmap_atomic(buffer);
|
|
}
|
|
|
|
bio_endio(bio);
|
|
return BLK_QC_T_NONE;
|
|
}
|
|
|
|
static int simdisk_open(struct block_device *bdev, fmode_t mode)
|
|
{
|
|
struct simdisk *dev = bdev->bd_disk->private_data;
|
|
|
|
spin_lock(&dev->lock);
|
|
if (!dev->users)
|
|
check_disk_change(bdev);
|
|
++dev->users;
|
|
spin_unlock(&dev->lock);
|
|
return 0;
|
|
}
|
|
|
|
static void simdisk_release(struct gendisk *disk, fmode_t mode)
|
|
{
|
|
struct simdisk *dev = disk->private_data;
|
|
spin_lock(&dev->lock);
|
|
--dev->users;
|
|
spin_unlock(&dev->lock);
|
|
}
|
|
|
|
static const struct block_device_operations simdisk_ops = {
|
|
.owner = THIS_MODULE,
|
|
.open = simdisk_open,
|
|
.release = simdisk_release,
|
|
};
|
|
|
|
static struct simdisk *sddev;
|
|
static struct proc_dir_entry *simdisk_procdir;
|
|
|
|
static int simdisk_attach(struct simdisk *dev, const char *filename)
|
|
{
|
|
int err = 0;
|
|
|
|
filename = kstrdup(filename, GFP_KERNEL);
|
|
if (filename == NULL)
|
|
return -ENOMEM;
|
|
|
|
spin_lock(&dev->lock);
|
|
|
|
if (dev->fd != -1) {
|
|
err = -EBUSY;
|
|
goto out;
|
|
}
|
|
dev->fd = simc_open(filename, O_RDWR, 0);
|
|
if (dev->fd == -1) {
|
|
pr_err("SIMDISK: Can't open %s: %d\n", filename, errno);
|
|
err = -ENODEV;
|
|
goto out;
|
|
}
|
|
dev->size = simc_lseek(dev->fd, 0, SEEK_END);
|
|
set_capacity(dev->gd, dev->size >> SECTOR_SHIFT);
|
|
dev->filename = filename;
|
|
pr_info("SIMDISK: %s=%s\n", dev->gd->disk_name, dev->filename);
|
|
out:
|
|
if (err)
|
|
kfree(filename);
|
|
spin_unlock(&dev->lock);
|
|
|
|
return err;
|
|
}
|
|
|
|
static int simdisk_detach(struct simdisk *dev)
|
|
{
|
|
int err = 0;
|
|
|
|
spin_lock(&dev->lock);
|
|
|
|
if (dev->users != 0) {
|
|
err = -EBUSY;
|
|
} else if (dev->fd != -1) {
|
|
if (simc_close(dev->fd)) {
|
|
pr_err("SIMDISK: error closing %s: %d\n",
|
|
dev->filename, errno);
|
|
err = -EIO;
|
|
} else {
|
|
pr_info("SIMDISK: %s detached from %s\n",
|
|
dev->gd->disk_name, dev->filename);
|
|
dev->fd = -1;
|
|
kfree(dev->filename);
|
|
dev->filename = NULL;
|
|
}
|
|
}
|
|
spin_unlock(&dev->lock);
|
|
return err;
|
|
}
|
|
|
|
static ssize_t proc_read_simdisk(struct file *file, char __user *buf,
|
|
size_t size, loff_t *ppos)
|
|
{
|
|
struct simdisk *dev = PDE_DATA(file_inode(file));
|
|
const char *s = dev->filename;
|
|
if (s) {
|
|
ssize_t n = simple_read_from_buffer(buf, size, ppos,
|
|
s, strlen(s));
|
|
if (n < 0)
|
|
return n;
|
|
buf += n;
|
|
size -= n;
|
|
}
|
|
return simple_read_from_buffer(buf, size, ppos, "\n", 1);
|
|
}
|
|
|
|
static ssize_t proc_write_simdisk(struct file *file, const char __user *buf,
|
|
size_t count, loff_t *ppos)
|
|
{
|
|
char *tmp = memdup_user_nul(buf, count);
|
|
struct simdisk *dev = PDE_DATA(file_inode(file));
|
|
int err;
|
|
|
|
if (IS_ERR(tmp))
|
|
return PTR_ERR(tmp);
|
|
|
|
err = simdisk_detach(dev);
|
|
if (err != 0)
|
|
goto out_free;
|
|
|
|
if (count > 0 && tmp[count - 1] == '\n')
|
|
tmp[count - 1] = 0;
|
|
|
|
if (tmp[0])
|
|
err = simdisk_attach(dev, tmp);
|
|
|
|
if (err == 0)
|
|
err = count;
|
|
out_free:
|
|
kfree(tmp);
|
|
return err;
|
|
}
|
|
|
|
static const struct file_operations fops = {
|
|
.read = proc_read_simdisk,
|
|
.write = proc_write_simdisk,
|
|
.llseek = default_llseek,
|
|
};
|
|
|
|
static int __init simdisk_setup(struct simdisk *dev, int which,
|
|
struct proc_dir_entry *procdir)
|
|
{
|
|
char tmp[2] = { '0' + which, 0 };
|
|
|
|
dev->fd = -1;
|
|
dev->filename = NULL;
|
|
spin_lock_init(&dev->lock);
|
|
dev->users = 0;
|
|
|
|
dev->queue = blk_alloc_queue(GFP_KERNEL);
|
|
if (dev->queue == NULL) {
|
|
pr_err("blk_alloc_queue failed\n");
|
|
goto out_alloc_queue;
|
|
}
|
|
|
|
blk_queue_make_request(dev->queue, simdisk_make_request);
|
|
dev->queue->queuedata = dev;
|
|
|
|
dev->gd = alloc_disk(SIMDISK_MINORS);
|
|
if (dev->gd == NULL) {
|
|
pr_err("alloc_disk failed\n");
|
|
goto out_alloc_disk;
|
|
}
|
|
dev->gd->major = simdisk_major;
|
|
dev->gd->first_minor = which;
|
|
dev->gd->fops = &simdisk_ops;
|
|
dev->gd->queue = dev->queue;
|
|
dev->gd->private_data = dev;
|
|
snprintf(dev->gd->disk_name, 32, "simdisk%d", which);
|
|
set_capacity(dev->gd, 0);
|
|
add_disk(dev->gd);
|
|
|
|
dev->procfile = proc_create_data(tmp, 0644, procdir, &fops, dev);
|
|
return 0;
|
|
|
|
out_alloc_disk:
|
|
blk_cleanup_queue(dev->queue);
|
|
dev->queue = NULL;
|
|
out_alloc_queue:
|
|
return -ENOMEM;
|
|
}
|
|
|
|
static int __init simdisk_init(void)
|
|
{
|
|
int i;
|
|
|
|
if (register_blkdev(simdisk_major, "simdisk") < 0) {
|
|
pr_err("SIMDISK: register_blkdev: %d\n", simdisk_major);
|
|
return -EIO;
|
|
}
|
|
pr_info("SIMDISK: major: %d\n", simdisk_major);
|
|
|
|
if (n_files > simdisk_count)
|
|
simdisk_count = n_files;
|
|
if (simdisk_count > MAX_SIMDISK_COUNT)
|
|
simdisk_count = MAX_SIMDISK_COUNT;
|
|
|
|
sddev = kmalloc_array(simdisk_count, sizeof(*sddev), GFP_KERNEL);
|
|
if (sddev == NULL)
|
|
goto out_unregister;
|
|
|
|
simdisk_procdir = proc_mkdir("simdisk", 0);
|
|
if (simdisk_procdir == NULL)
|
|
goto out_free_unregister;
|
|
|
|
for (i = 0; i < simdisk_count; ++i) {
|
|
if (simdisk_setup(sddev + i, i, simdisk_procdir) == 0) {
|
|
if (filename[i] != NULL && filename[i][0] != 0 &&
|
|
(n_files == 0 || i < n_files))
|
|
simdisk_attach(sddev + i, filename[i]);
|
|
}
|
|
}
|
|
|
|
return 0;
|
|
|
|
out_free_unregister:
|
|
kfree(sddev);
|
|
out_unregister:
|
|
unregister_blkdev(simdisk_major, "simdisk");
|
|
return -ENOMEM;
|
|
}
|
|
module_init(simdisk_init);
|
|
|
|
static void simdisk_teardown(struct simdisk *dev, int which,
|
|
struct proc_dir_entry *procdir)
|
|
{
|
|
char tmp[2] = { '0' + which, 0 };
|
|
|
|
simdisk_detach(dev);
|
|
if (dev->gd)
|
|
del_gendisk(dev->gd);
|
|
if (dev->queue)
|
|
blk_cleanup_queue(dev->queue);
|
|
remove_proc_entry(tmp, procdir);
|
|
}
|
|
|
|
static void __exit simdisk_exit(void)
|
|
{
|
|
int i;
|
|
|
|
for (i = 0; i < simdisk_count; ++i)
|
|
simdisk_teardown(sddev + i, i, simdisk_procdir);
|
|
remove_proc_entry("simdisk", 0);
|
|
kfree(sddev);
|
|
unregister_blkdev(simdisk_major, "simdisk");
|
|
}
|
|
module_exit(simdisk_exit);
|
|
|
|
MODULE_ALIAS_BLOCKDEV_MAJOR(SIMDISK_MAJOR);
|
|
|
|
MODULE_LICENSE("GPL");
|