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lp: cdev lock_kernel() pushdown

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Signed-off-by: Jonathan Corbet <corbet@lwn.net>
This commit is contained in:
Jonathan Corbet 2008-05-15 11:29:38 -06:00
parent 12ead6b098
commit abedd296e9
1 changed files with 26 additions and 12 deletions
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38
drivers/char/lp.c
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@ -126,6 +126,7 @@
#include <linux/device.h>
#include <linux/wait.h>
#include <linux/jiffies.h>
#include <linux/smp_lock.h>
#include <linux/parport.h>
#undef LP_STATS
@ -489,14 +490,21 @@ static ssize_t lp_read(struct file * file, char __user * buf,
static int lp_open(struct inode * inode, struct file * file)
{
unsigned int minor = iminor(inode);
int ret = 0;
if (minor >= LP_NO)
return -ENXIO;
if ((LP_F(minor) & LP_EXIST) == 0)
return -ENXIO;
if (test_and_set_bit(LP_BUSY_BIT_POS, &LP_F(minor)))
return -EBUSY;
lock_kernel();
if (minor >= LP_NO) {
ret = -ENXIO;
goto out;
}
if ((LP_F(minor) & LP_EXIST) == 0) {
ret = -ENXIO;
goto out;
}
if (test_and_set_bit(LP_BUSY_BIT_POS, &LP_F(minor))) {
ret = -EBUSY;
goto out;
}
/* If ABORTOPEN is set and the printer is offline or out of paper,
we may still want to open it to perform ioctl()s. Therefore we
have commandeered O_NONBLOCK, even though it is being used in
@ -510,21 +518,25 @@ static int lp_open(struct inode * inode, struct file * file)
if (status & LP_POUTPA) {
printk(KERN_INFO "lp%d out of paper\n", minor);
LP_F(minor) &= ~LP_BUSY;
return -ENOSPC;
ret = -ENOSPC;
goto out;
} else if (!(status & LP_PSELECD)) {
printk(KERN_INFO "lp%d off-line\n", minor);
LP_F(minor) &= ~LP_BUSY;
return -EIO;
ret = -EIO;
goto out;
} else if (!(status & LP_PERRORP)) {
printk(KERN_ERR "lp%d printer error\n", minor);
LP_F(minor) &= ~LP_BUSY;
return -EIO;
ret = -EIO;
goto out;
}
}
lp_table[minor].lp_buffer = kmalloc(LP_BUFFER_SIZE, GFP_KERNEL);
if (!lp_table[minor].lp_buffer) {
LP_F(minor) &= ~LP_BUSY;
return -ENOMEM;
ret = -ENOMEM;
goto out;
}
/* Determine if the peripheral supports ECP mode */
lp_claim_parport_or_block (&lp_table[minor]);
@ -540,7 +552,9 @@ static int lp_open(struct inode * inode, struct file * file)
parport_negotiate (lp_table[minor].dev->port, IEEE1284_MODE_COMPAT);
lp_release_parport (&lp_table[minor]);
lp_table[minor].current_mode = IEEE1284_MODE_COMPAT;
return 0;
out:
unlock_kernel();
return ret;
}
static int lp_release(struct inode * inode, struct file * file)