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mem_class: use minor as index instead of searching the array 

Declare the device list with the minor numbers as the index, which saves us from
searching for a matching list entry. Remove old devfs permissions declaration.

Signed-off-by: Kay Sievers <kay.sievers@vrfy.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
This commit is contained in:
Kay Sievers 2009-07-04 16:51:29 +02:00 committed by Greg Kroah-Hartman
parent a4dbd6740d
commit 389e0cb9a1
1 changed files with 40 additions and 42 deletions
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78
drivers/char/mem.c
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@ -864,71 +864,67 @@ static const struct file_operations kmsg_fops = {
.write = kmsg_write,
};
static const struct {
unsigned int minor;
char *name;
umode_t mode;
static const struct memdev {
const char *name;
const struct file_operations *fops;
struct backing_dev_info *dev_info;
} devlist[] = { /* list of minor devices */
{1, "mem", S_IRUSR | S_IWUSR | S_IRGRP, &mem_fops,
&directly_mappable_cdev_bdi},
} devlist[] = {
[ 1] = { "mem", &mem_fops, &directly_mappable_cdev_bdi },
#ifdef CONFIG_DEVKMEM
{2, "kmem", S_IRUSR | S_IWUSR | S_IRGRP, &kmem_fops,
&directly_mappable_cdev_bdi},
[ 2] = { "kmem", &kmem_fops, &directly_mappable_cdev_bdi },
#endif
{3, "null", S_IRUGO | S_IWUGO, &null_fops, NULL},
[ 3] = {"null", &null_fops, NULL },
#ifdef CONFIG_DEVPORT
{4, "port", S_IRUSR | S_IWUSR | S_IRGRP, &port_fops, NULL},
[ 4] = { "port", &port_fops, NULL },
#endif
{5, "zero", S_IRUGO | S_IWUGO, &zero_fops, &zero_bdi},
{7, "full", S_IRUGO | S_IWUGO, &full_fops, NULL},
{8, "random", S_IRUGO | S_IWUSR, &random_fops, NULL},
{9, "urandom", S_IRUGO | S_IWUSR, &urandom_fops, NULL},
{11,"kmsg", S_IRUGO | S_IWUSR, &kmsg_fops, NULL},
[ 5] = { "zero", &zero_fops, &zero_bdi },
[ 6] = { "full", &full_fops, NULL },
[ 7] = { "random", &random_fops, NULL },
[ 9] = { "urandom", &urandom_fops, NULL },
[11] = { "kmsg", &kmsg_fops, NULL },
#ifdef CONFIG_CRASH_DUMP
{12,"oldmem", S_IRUSR | S_IWUSR | S_IRGRP, &oldmem_fops, NULL},
[12] = { "oldmem", &oldmem_fops, NULL },
#endif
};
static int memory_open(struct inode *inode, struct file *filp)
{
int ret = 0;
int i;
int minor;
const struct memdev *dev;
int ret = -ENXIO;
lock_kernel();
for (i = 0; i < ARRAY_SIZE(devlist); i++) {
if (devlist[i].minor == iminor(inode)) {
filp->f_op = devlist[i].fops;
if (devlist[i].dev_info) {
filp->f_mapping->backing_dev_info =
devlist[i].dev_info;
}
minor = iminor(inode);
if (minor >= ARRAY_SIZE(devlist))
goto out;
break;
}
}
dev = &devlist[minor];
if (!dev->fops)
goto out;
if (i == ARRAY_SIZE(devlist))
ret = -ENXIO;
filp->f_op = dev->fops;
if (dev->dev_info)
filp->f_mapping->backing_dev_info = dev->dev_info;
if (dev->fops->open)
ret = dev->fops->open(inode, filp);
else
if (filp->f_op && filp->f_op->open)
ret = filp->f_op->open(inode, filp);
ret = 0;
out:
unlock_kernel();
return ret;
}
static const struct file_operations memory_fops = {
.open = memory_open, /* just a selector for the real open */
.open = memory_open,
};
static struct class *mem_class;
static int __init chr_dev_init(void)
{
int i;
int minor;
int err;
err = bdi_init(&zero_bdi);
@ -939,10 +935,12 @@ static int __init chr_dev_init(void)
printk("unable to get major %d for memory devs\n", MEM_MAJOR);
mem_class = class_create(THIS_MODULE, "mem");
for (i = 0; i < ARRAY_SIZE(devlist); i++)
device_create(mem_class, NULL,
MKDEV(MEM_MAJOR, devlist[i].minor), NULL,
devlist[i].name);
for (minor = 1; minor < ARRAY_SIZE(devlist); minor++) {
if (!devlist[minor].name)
continue;
device_create(mem_class, NULL, MKDEV(MEM_MAJOR, minor),
NULL, devlist[minor].name);
}
return 0;
}