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Staging: Use proper mutexes in the tsi-148 VME driver

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The VME core and tsi-148 driver currently use semaphores as mutexes. Switch to proper
mutex implementation.

Signed-off-by: Martyn Welch <martyn.welch@gefanuc.com>
Reviewed-by: Emilio G. Cota <cota@braap.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
This commit is contained in:
Martyn Welch 2009-08-11 16:20:22 +01:00 committed by Greg Kroah-Hartman
parent 238add523b
commit 400822fec4
3 changed files with 71 additions and 83 deletions
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86
drivers/staging/vme/bridges/vme_tsi148.c
View File

@ -76,13 +76,13 @@ void (*lm_callback[4])(int); /* Called in interrupt handler, be careful! */
void *crcsr_kernel;
dma_addr_t crcsr_bus;
struct vme_master_resource *flush_image;
struct semaphore vme_rmw; /* Only one RMW cycle at a time */
struct semaphore vme_int; /*
struct mutex vme_rmw; /* Only one RMW cycle at a time */
struct mutex vme_int; /*
* Only one VME interrupt can be
* generated at a time, provide locking
*/
struct semaphore vme_irq; /* Locking for VME irq callback configuration */
struct semaphore vme_lm; /* Locking for location monitor operations */
struct mutex vme_irq; /* Locking for VME irq callback configuration */
struct mutex vme_lm; /* Locking for location monitor operations */
static char driver_name[] = "vme_tsi148";
@ -445,11 +445,10 @@ int tsi148_request_irq(int level, int statid,
{
u32 tmp;
/* Get semaphore */
down(&(vme_irq));
mutex_lock(&(vme_irq));
if(tsi148_bridge->irq[level - 1].callback[statid].func) {
up(&(vme_irq));
mutex_unlock(&(vme_irq));
printk("VME Interrupt already taken\n");
return -EBUSY;
}
@ -468,8 +467,7 @@ int tsi148_request_irq(int level, int statid,
tmp |= TSI148_LCSR_INTEN_IRQEN[level - 1];
iowrite32be(tmp, tsi148_bridge->base + TSI148_LCSR_INTEN);
/* Release semaphore */
up(&(vme_irq));
mutex_unlock(&(vme_irq));
return 0;
}
@ -482,8 +480,7 @@ void tsi148_free_irq(int level, int statid)
u32 tmp;
struct pci_dev *pdev;
/* Get semaphore */
down(&(vme_irq));
mutex_lock(&(vme_irq));
tsi148_bridge->irq[level - 1].count--;
@ -505,22 +502,18 @@ void tsi148_free_irq(int level, int statid)
tsi148_bridge->irq[level - 1].callback[statid].func = NULL;
tsi148_bridge->irq[level - 1].callback[statid].priv_data = NULL;
/* Release semaphore */
up(&(vme_irq));
mutex_unlock(&(vme_irq));
}
/*
* Generate a VME bus interrupt at the requested level & vector. Wait for
* interrupt to be acked.
*
* Only one interrupt can be generated at a time - so add a semaphore.
*/
int tsi148_generate_irq(int level, int statid)
{
u32 tmp;
/* Get semaphore */
down(&(vme_int));
mutex_lock(&(vme_int));
/* Read VICR register */
tmp = ioread32be(tsi148_bridge->base + TSI148_LCSR_VICR);
@ -537,8 +530,7 @@ int tsi148_generate_irq(int level, int statid)
/* XXX Consider implementing a timeout? */
wait_event_interruptible(iack_queue, tsi148_iack_received());
/* Release semaphore */
up(&(vme_int));
mutex_unlock(&(vme_int));
return 0;
}
@ -1379,7 +1371,7 @@ skip_chk:
}
/* XXX We need to change vme_master_resource->sem to a spinlock so that read
/* XXX We need to change vme_master_resource->mtx to a spinlock so that read
* and write functions can be used in an interrupt context
*/
ssize_t tsi148_master_write(struct vme_master_resource *image, void *buf,
@ -1455,7 +1447,7 @@ unsigned int tsi148_master_rmw(struct vme_master_resource *image,
i = image->number;
/* Locking as we can only do one of these at a time */
down(&(vme_rmw));
mutex_lock(&(vme_rmw));
/* Lock image */
spin_lock(&(image->lock));
@ -1490,7 +1482,7 @@ unsigned int tsi148_master_rmw(struct vme_master_resource *image,
spin_unlock(&(image->lock));
up(&(vme_rmw));
mutex_unlock(&(vme_rmw));
return result;
}
@ -1867,7 +1859,7 @@ int tsi148_dma_list_exec(struct vme_dma_list *list)
ctrlr = list->parent;
down(&(ctrlr->sem));
mutex_lock(&(ctrlr->mtx));
channel = ctrlr->number;
@ -1878,7 +1870,7 @@ int tsi148_dma_list_exec(struct vme_dma_list *list)
* Return busy.
*/
/* Need to add to pending here */
up(&(ctrlr->sem));
mutex_unlock(&(ctrlr->mtx));
return -EBUSY;
} else {
list_add(&(list->list), &(ctrlr->running));
@ -1932,7 +1924,7 @@ int tsi148_dma_list_exec(struct vme_dma_list *list)
bus_addr = virt_to_bus(&(entry->descriptor));
up(&(ctrlr->sem));
mutex_unlock(&(ctrlr->mtx));
reg_split(bus_addr, &bus_addr_high, &bus_addr_low);
@ -1959,9 +1951,9 @@ int tsi148_dma_list_exec(struct vme_dma_list *list)
}
/* Remove list from running list */
down(&(ctrlr->sem));
mutex_lock(&(ctrlr->mtx));
list_del(&(list->list));
up(&(ctrlr->sem));
mutex_unlock(&(ctrlr->mtx));
return retval;
}
@ -1999,13 +1991,12 @@ int tsi148_lm_set(unsigned long long lm_base, vme_address_t aspace,
u32 lm_base_high, lm_base_low, lm_ctl = 0;
int i;
/* Get semaphore */
down(&(vme_lm));
mutex_lock(&(vme_lm));
/* If we already have a callback attached, we can't move it! */
for (i = 0; i < 4; i++) {
if(lm_callback[i] != NULL) {
up(&(vme_lm));
mutex_unlock(&(vme_lm));
printk("Location monitor callback attached, can't "
"reset\n");
return -EBUSY;
@ -2026,7 +2017,7 @@ int tsi148_lm_set(unsigned long long lm_base, vme_address_t aspace,
lm_ctl |= TSI148_LCSR_LMAT_AS_A64;
break;
default:
up(&(vme_lm));
mutex_unlock(&(vme_lm));
printk("Invalid address space\n");
return -EINVAL;
break;
@ -2047,7 +2038,7 @@ int tsi148_lm_set(unsigned long long lm_base, vme_address_t aspace,
iowrite32be(lm_base_low, tsi148_bridge->base + TSI148_LCSR_LMBAL);
iowrite32be(lm_ctl, tsi148_bridge->base + TSI148_LCSR_LMAT);
up(&(vme_lm));
mutex_unlock(&(vme_lm));
return 0;
}
@ -2060,8 +2051,7 @@ int tsi148_lm_get(unsigned long long *lm_base, vme_address_t *aspace,
{
u32 lm_base_high, lm_base_low, lm_ctl, enabled = 0;
/* Get semaphore */
down(&(vme_lm));
mutex_lock(&(vme_lm));
lm_base_high = ioread32be(tsi148_bridge->base + TSI148_LCSR_LMBAU);
lm_base_low = ioread32be(tsi148_bridge->base + TSI148_LCSR_LMBAL);
@ -2094,7 +2084,7 @@ int tsi148_lm_get(unsigned long long *lm_base, vme_address_t *aspace,
if (lm_ctl & TSI148_LCSR_LMAT_DATA)
*cycle |= VME_DATA;
up(&(vme_lm));
mutex_unlock(&(vme_lm));
return enabled;
}
@ -2108,20 +2098,19 @@ int tsi148_lm_attach(int monitor, void (*callback)(int))
{
u32 lm_ctl, tmp;
/* Get semaphore */
down(&(vme_lm));
mutex_lock(&(vme_lm));
/* Ensure that the location monitor is configured - need PGM or DATA */
lm_ctl = ioread32be(tsi148_bridge->base + TSI148_LCSR_LMAT);
if ((lm_ctl & (TSI148_LCSR_LMAT_PGM | TSI148_LCSR_LMAT_DATA)) == 0) {
up(&(vme_lm));
mutex_unlock(&(vme_lm));
printk("Location monitor not properly configured\n");
return -EINVAL;
}
/* Check that a callback isn't already attached */
if (lm_callback[monitor] != NULL) {
up(&(vme_lm));
mutex_unlock(&(vme_lm));
printk("Existing callback attached\n");
return -EBUSY;
}
@ -2144,7 +2133,7 @@ int tsi148_lm_attach(int monitor, void (*callback)(int))
iowrite32be(lm_ctl, tsi148_bridge->base + TSI148_LCSR_LMAT);
}
up(&(vme_lm));
mutex_unlock(&(vme_lm));
return 0;
}
@ -2156,8 +2145,7 @@ int tsi148_lm_detach(int monitor)
{
u32 lm_en, tmp;
/* Get semaphore */
down(&(vme_lm));
mutex_lock(&(vme_lm));
/* Disable Location Monitor and ensure previous interrupts are clear */
lm_en = ioread32be(tsi148_bridge->base + TSI148_LCSR_INTEN);
@ -2182,7 +2170,7 @@ int tsi148_lm_detach(int monitor)
iowrite32be(tmp, tsi148_bridge->base + TSI148_LCSR_LMAT);
}
up(&(vme_lm));
mutex_unlock(&(vme_lm));
return 0;
}
@ -2347,10 +2335,10 @@ static int tsi148_probe(struct pci_dev *pdev, const struct pci_device_id *id)
init_waitqueue_head(&dma_queue[0]);
init_waitqueue_head(&dma_queue[1]);
init_waitqueue_head(&iack_queue);
init_MUTEX(&(vme_int));
init_MUTEX(&(vme_irq));
init_MUTEX(&(vme_rmw));
init_MUTEX(&(vme_lm));
mutex_init(&(vme_int));
mutex_init(&(vme_irq));
mutex_init(&(vme_rmw));
mutex_init(&(vme_lm));
tsi148_bridge->parent = &(pdev->dev);
strcpy(tsi148_bridge->name, driver_name);
@ -2436,7 +2424,7 @@ static int tsi148_probe(struct pci_dev *pdev, const struct pci_device_id *id)
goto err_slave;
}
slave_image->parent = tsi148_bridge;
init_MUTEX(&(slave_image->sem));
mutex_init(&(slave_image->mtx));
slave_image->locked = 0;
slave_image->number = i;
slave_image->address_attr = VME_A16 | VME_A24 | VME_A32 |
@ -2462,7 +2450,7 @@ static int tsi148_probe(struct pci_dev *pdev, const struct pci_device_id *id)
goto err_dma;
}
dma_ctrlr->parent = tsi148_bridge;
init_MUTEX(&(dma_ctrlr->sem));
mutex_init(&(dma_ctrlr->mtx));
dma_ctrlr->locked = 0;
dma_ctrlr->number = i;
INIT_LIST_HEAD(&(dma_ctrlr->pending));

60
drivers/staging/vme/vme.c
View File

@ -28,15 +28,15 @@
#include <linux/device.h>
#include <linux/dma-mapping.h>
#include <linux/syscalls.h>
#include <linux/semaphore.h>
#include <linux/mutex.h>
#include <linux/spinlock.h>
#include "vme.h"
#include "vme_bridge.h"
/* Bitmask and semaphore to keep track of bridge numbers */
/* Bitmask and mutex to keep track of bridge numbers */
static unsigned int vme_bus_numbers;
DECLARE_MUTEX(vme_bus_num_sem);
DEFINE_MUTEX(vme_bus_num_mtx);
static void __exit vme_exit (void);
static int __init vme_init (void);
@ -251,17 +251,17 @@ struct vme_resource * vme_slave_request(struct device *dev,
}
/* Find an unlocked and compatible image */
down(&(slave_image->sem));
mutex_lock(&(slave_image->mtx));
if(((slave_image->address_attr & address) == address) &&
((slave_image->cycle_attr & cycle) == cycle) &&
(slave_image->locked == 0)) {
slave_image->locked = 1;
up(&(slave_image->sem));
mutex_unlock(&(slave_image->mtx));
allocated_image = slave_image;
break;
}
up(&(slave_image->sem));
mutex_unlock(&(slave_image->mtx));
}
/* No free image */
@ -280,9 +280,9 @@ struct vme_resource * vme_slave_request(struct device *dev,
err_alloc:
/* Unlock image */
down(&(slave_image->sem));
mutex_lock(&(slave_image->mtx));
slave_image->locked = 0;
up(&(slave_image->sem));
mutex_unlock(&(slave_image->mtx));
err_image:
err_bus:
return NULL;
@ -365,12 +365,12 @@ void vme_slave_free(struct vme_resource *resource)
}
/* Unlock image */
down(&(slave_image->sem));
mutex_lock(&(slave_image->mtx));
if (slave_image->locked == 0)
printk(KERN_ERR "Image is already free\n");
slave_image->locked = 0;
up(&(slave_image->sem));
mutex_unlock(&(slave_image->mtx));
/* Free up resource memory */
kfree(resource);
@ -668,14 +668,14 @@ struct vme_resource *vme_request_dma(struct device *dev)
}
/* Find an unlocked controller */
down(&(dma_ctrlr->sem));
mutex_lock(&(dma_ctrlr->mtx));
if(dma_ctrlr->locked == 0) {
dma_ctrlr->locked = 1;
up(&(dma_ctrlr->sem));
mutex_unlock(&(dma_ctrlr->mtx));
allocated_ctrlr = dma_ctrlr;
break;
}
up(&(dma_ctrlr->sem));
mutex_unlock(&(dma_ctrlr->mtx));
}
/* Check to see if we found a resource */
@ -694,9 +694,9 @@ struct vme_resource *vme_request_dma(struct device *dev)
err_alloc:
/* Unlock image */
down(&(dma_ctrlr->sem));
mutex_lock(&(dma_ctrlr->mtx));
dma_ctrlr->locked = 0;
up(&(dma_ctrlr->sem));
mutex_unlock(&(dma_ctrlr->mtx));
err_ctrlr:
err_bus:
return NULL;
@ -726,7 +726,7 @@ struct vme_dma_list *vme_new_dma_list(struct vme_resource *resource)
}
INIT_LIST_HEAD(&(dma_list->entries));
dma_list->parent = ctrlr;
init_MUTEX(&(dma_list->sem));
mutex_init(&(dma_list->mtx));
return dma_list;
}
@ -876,14 +876,14 @@ int vme_dma_list_add(struct vme_dma_list *list, struct vme_dma_attr *src,
return -EINVAL;
}
if (down_trylock(&(list->sem))) {
if (mutex_trylock(&(list->mtx))) {
printk("Link List already submitted\n");
return -EINVAL;
}
retval = bridge->dma_list_add(list, src, dest, count);
up(&(list->sem));
mutex_unlock(&(list->mtx));
return retval;
}
@ -899,11 +899,11 @@ int vme_dma_list_exec(struct vme_dma_list *list)
return -EINVAL;
}
down(&(list->sem));
mutex_lock(&(list->mtx));
retval = bridge->dma_list_exec(list);
up(&(list->sem));
mutex_unlock(&(list->mtx));
return retval;
}
@ -919,7 +919,7 @@ int vme_dma_list_free(struct vme_dma_list *list)
return -EINVAL;
}
if (down_trylock(&(list->sem))) {
if (mutex_trylock(&(list->mtx))) {
printk("Link List in use\n");
return -EINVAL;
}
@ -931,10 +931,10 @@ int vme_dma_list_free(struct vme_dma_list *list)
retval = bridge->dma_list_empty(list);
if (retval) {
printk("Unable to empty link-list entries\n");
up(&(list->sem));
mutex_unlock(&(list->mtx));
return retval;
}
up(&(list->sem));
mutex_unlock(&(list->mtx));
kfree(list);
return retval;
@ -952,20 +952,20 @@ int vme_dma_free(struct vme_resource *resource)
ctrlr = list_entry(resource->entry, struct vme_dma_resource, list);
if (down_trylock(&(ctrlr->sem))) {
if (mutex_trylock(&(ctrlr->mtx))) {
printk("Resource busy, can't free\n");
return -EBUSY;
}
if (!(list_empty(&(ctrlr->pending)) && list_empty(&(ctrlr->running)))) {
printk("Resource still processing transfers\n");
up(&(ctrlr->sem));
mutex_unlock(&(ctrlr->mtx));
return -EBUSY;
}
ctrlr->locked = 0;
up(&(ctrlr->sem));
mutex_unlock(&(ctrlr->mtx));
return 0;
}
@ -1149,23 +1149,23 @@ static int vme_alloc_bus_num(void)
{
int i;
down(&vme_bus_num_sem);
mutex_lock(&vme_bus_num_mtx);
for (i = 0; i < sizeof(vme_bus_numbers) * 8; i++) {
if (((vme_bus_numbers >> i) & 0x1) == 0) {
vme_bus_numbers |= (0x1 << i);
break;
}
}
up(&vme_bus_num_sem);
mutex_unlock(&vme_bus_num_mtx);
return i;
}
static void vme_free_bus_num(int bus)
{
down(&vme_bus_num_sem);
mutex_lock(&vme_bus_num_mtx);
vme_bus_numbers |= ~(0x1 << bus);
up(&vme_bus_num_sem);
mutex_unlock(&vme_bus_num_mtx);
}
int vme_register_bridge (struct vme_bridge *bridge)

8
drivers/staging/vme/vme_bridge.h
View File

@ -11,7 +11,7 @@ struct vme_master_resource {
struct vme_bridge *parent;
/*
* We are likely to need to access the VME bus in interrupt context, so
* protect master routines with a spinlock rather than a semaphore.
* protect master routines with a spinlock rather than a mutex.
*/
spinlock_t lock;
int locked;
@ -26,7 +26,7 @@ struct vme_master_resource {
struct vme_slave_resource {
struct list_head list;
struct vme_bridge *parent;
struct semaphore sem;
struct mutex mtx;
int locked;
int number;
vme_address_t address_attr;
@ -53,13 +53,13 @@ struct vme_dma_list {
struct list_head list;
struct vme_dma_resource *parent;
struct list_head entries;
struct semaphore sem;
struct mutex mtx;
};
struct vme_dma_resource {
struct list_head list;
struct vme_bridge *parent;
struct semaphore sem;
struct mutex mtx;
int locked;
int number;
struct list_head pending;