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Coda: replace BKL with mutex

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Replace the BKL with a mutex to protect the venus_comm structure which
binds the mountpoint with the character device and holds the upcall
queues.

Signed-off-by: Yoshihisa Abe <yoshiabe@cs.cmu.edu>
Signed-off-by: Jan Harkes <jaharkes@cs.cmu.edu>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
This commit is contained in:
Yoshihisa Abe
2010-10-25 02:03:46 -04:00
committed by Linus Torvalds
parent f7cc02b871
commit da47c19e5c
4 changed files with 70 additions and 50 deletions
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28
fs/coda/psdev.c
View File

@@ -35,7 +35,7 @@
#include <linux/poll.h>
#include <linux/init.h>
#include <linux/list.h>
#include <linux/smp_lock.h>
#include <linux/mutex.h>
#include <linux/device.h>
#include <asm/io.h>
#include <asm/system.h>
@@ -67,8 +67,10 @@ static unsigned int coda_psdev_poll(struct file *file, poll_table * wait)
unsigned int mask = POLLOUT | POLLWRNORM;
poll_wait(file, &vcp->vc_waitq, wait);
mutex_lock(&vcp->vc_mutex);
if (!list_empty(&vcp->vc_pending))
mask |= POLLIN | POLLRDNORM;
mutex_unlock(&vcp->vc_mutex);
return mask;
}
@@ -143,7 +145,7 @@ static ssize_t coda_psdev_write(struct file *file, const char __user *buf,
}
/* Look for the message on the processing queue. */
lock_kernel();
mutex_lock(&vcp->vc_mutex);
list_for_each(lh, &vcp->vc_processing) {
tmp = list_entry(lh, struct upc_req , uc_chain);
if (tmp->uc_unique == hdr.unique) {
@@ -152,7 +154,7 @@ static ssize_t coda_psdev_write(struct file *file, const char __user *buf,
break;
}
}
unlock_kernel();
mutex_unlock(&vcp->vc_mutex);
if (!req) {
printk("psdev_write: msg (%d, %d) not found\n",
@@ -207,7 +209,7 @@ static ssize_t coda_psdev_read(struct file * file, char __user * buf,
if (nbytes == 0)
return 0;
lock_kernel();
mutex_lock(&vcp->vc_mutex);
add_wait_queue(&vcp->vc_waitq, &wait);
set_current_state(TASK_INTERRUPTIBLE);
@@ -221,7 +223,9 @@ static ssize_t coda_psdev_read(struct file * file, char __user * buf,
retval = -ERESTARTSYS;
break;
}
mutex_unlock(&vcp->vc_mutex);
schedule();
mutex_lock(&vcp->vc_mutex);
}
set_current_state(TASK_RUNNING);
@@ -254,7 +258,7 @@ static ssize_t coda_psdev_read(struct file * file, char __user * buf,
CODA_FREE(req->uc_data, sizeof(struct coda_in_hdr));
kfree(req);
out:
unlock_kernel();
mutex_unlock(&vcp->vc_mutex);
return (count ? count : retval);
}
@@ -267,10 +271,10 @@ static int coda_psdev_open(struct inode * inode, struct file * file)
if (idx < 0 || idx >= MAX_CODADEVS)
return -ENODEV;
lock_kernel();
err = -EBUSY;
vcp = &coda_comms[idx];
mutex_lock(&vcp->vc_mutex);
if (!vcp->vc_inuse) {
vcp->vc_inuse++;
@@ -284,7 +288,7 @@ static int coda_psdev_open(struct inode * inode, struct file * file)
err = 0;
}
unlock_kernel();
mutex_unlock(&vcp->vc_mutex);
return err;
}
@@ -299,7 +303,7 @@ static int coda_psdev_release(struct inode * inode, struct file * file)
return -1;
}
lock_kernel();
mutex_lock(&vcp->vc_mutex);
/* Wakeup clients so they can return. */
list_for_each_entry_safe(req, tmp, &vcp->vc_pending, uc_chain) {
@@ -324,7 +328,7 @@ static int coda_psdev_release(struct inode * inode, struct file * file)
file->private_data = NULL;
vcp->vc_inuse--;
unlock_kernel();
mutex_unlock(&vcp->vc_mutex);
return 0;
}
@@ -353,9 +357,11 @@ static int init_coda_psdev(void)
err = PTR_ERR(coda_psdev_class);
goto out_chrdev;
}
for (i = 0; i < MAX_CODADEVS; i++)
for (i = 0; i < MAX_CODADEVS; i++) {
mutex_init(&(&coda_comms[i])->vc_mutex);
device_create(coda_psdev_class, NULL,
MKDEV(CODA_PSDEV_MAJOR, i), NULL, "cfs%d", i);
}
coda_sysctl_init();
goto out;