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[PATCH] DVB: Fix locking problems and code cleanup

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Fix locking problems and code cleanup

Signed-off-by: Andrew de Quincey <adq_dvb@lidskialf.net>
Signed-off-by: Johannes Stezenbach <js@linuxtv.org>
Signed-off-by: Mauro Carvalho Chehab <mchehab@brturbo.com.br>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
This commit is contained in:
Andrew de Quincey
2005-12-01 00:51:49 -08:00
committed by Linus Torvalds
parent 69459f3d2f
commit ded9284684
1 changed files with 23 additions and 46 deletions
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69
drivers/media/dvb/dvb-core/dvb_ca_en50221.c
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@@ -35,7 +35,7 @@
#include <linux/moduleparam.h> #include <linux/moduleparam.h>
#include <linux/vmalloc.h> #include <linux/vmalloc.h>
#include <linux/delay.h> #include <linux/delay.h>
#include <linux/rwsem.h> #include <linux/spinlock.h>
#include <linux/sched.h> #include <linux/sched.h>
#include "dvb_ca_en50221.h" #include "dvb_ca_en50221.h"
@@ -111,9 +111,6 @@ struct dvb_ca_slot {
/* size of the buffer to use when talking to the CAM */ /* size of the buffer to use when talking to the CAM */
int link_buf_size; int link_buf_size;
/* semaphore for syncing access to slot structure */
struct rw_semaphore sem;
/* buffer for incoming packets */ /* buffer for incoming packets */
struct dvb_ringbuffer rx_buffer; struct dvb_ringbuffer rx_buffer;
@@ -602,14 +599,11 @@ static int dvb_ca_en50221_read_data(struct dvb_ca_private *ca, int slot, u8 * eb
if (ebuf == NULL) { if (ebuf == NULL) {
int buf_free; int buf_free;
down_read(&ca->slot_info[slot].sem);
if (ca->slot_info[slot].rx_buffer.data == NULL) { if (ca->slot_info[slot].rx_buffer.data == NULL) {
up_read(&ca->slot_info[slot].sem);
status = -EIO; status = -EIO;
goto exit; goto exit;
} }
buf_free = dvb_ringbuffer_free(&ca->slot_info[slot].rx_buffer); buf_free = dvb_ringbuffer_free(&ca->slot_info[slot].rx_buffer);
up_read(&ca->slot_info[slot].sem);
if (buf_free < (ca->slot_info[slot].link_buf_size + DVB_RINGBUFFER_PKTHDRSIZE)) { if (buf_free < (ca->slot_info[slot].link_buf_size + DVB_RINGBUFFER_PKTHDRSIZE)) {
status = -EAGAIN; status = -EAGAIN;
@@ -680,14 +674,11 @@ static int dvb_ca_en50221_read_data(struct dvb_ca_private *ca, int slot, u8 * eb
/* OK, add it to the receive buffer, or copy into external buffer if supplied */ /* OK, add it to the receive buffer, or copy into external buffer if supplied */
if (ebuf == NULL) { if (ebuf == NULL) {
down_read(&ca->slot_info[slot].sem);
if (ca->slot_info[slot].rx_buffer.data == NULL) { if (ca->slot_info[slot].rx_buffer.data == NULL) {
up_read(&ca->slot_info[slot].sem);
status = -EIO; status = -EIO;
goto exit; goto exit;
} }
dvb_ringbuffer_pkt_write(&ca->slot_info[slot].rx_buffer, buf, bytes_read); dvb_ringbuffer_pkt_write(&ca->slot_info[slot].rx_buffer, buf, bytes_read);
up_read(&ca->slot_info[slot].sem);
} else { } else {
memcpy(ebuf, buf, bytes_read); memcpy(ebuf, buf, bytes_read);
} }
@@ -802,12 +793,8 @@ static int dvb_ca_en50221_slot_shutdown(struct dvb_ca_private *ca, int slot)
{ {
dprintk("%s\n", __FUNCTION__); dprintk("%s\n", __FUNCTION__);
down_write(&ca->slot_info[slot].sem);
ca->pub->slot_shutdown(ca->pub, slot); ca->pub->slot_shutdown(ca->pub, slot);
ca->slot_info[slot].slot_state = DVB_CA_SLOTSTATE_NONE; ca->slot_info[slot].slot_state = DVB_CA_SLOTSTATE_NONE;
vfree(ca->slot_info[slot].rx_buffer.data);
ca->slot_info[slot].rx_buffer.data = NULL;
up_write(&ca->slot_info[slot].sem);
/* need to wake up all processes to check if they're now /* need to wake up all processes to check if they're now
trying to write to a defunct CAM */ trying to write to a defunct CAM */
@@ -893,7 +880,7 @@ void dvb_ca_en50221_frda_irq(struct dvb_ca_en50221 *pubca, int slot)
case DVB_CA_SLOTSTATE_RUNNING: case DVB_CA_SLOTSTATE_RUNNING:
if (ca->open) if (ca->open)
dvb_ca_en50221_read_data(ca, slot, NULL, 0); dvb_ca_en50221_thread_wakeup(ca);
break; break;
} }
} }
@@ -1127,16 +1114,16 @@ static int dvb_ca_en50221_thread(void *data)
break; break;
} }
rxbuf = vmalloc(RX_BUFFER_SIZE); if (ca->slot_info[slot].rx_buffer.data == NULL) {
if (rxbuf == NULL) { rxbuf = vmalloc(RX_BUFFER_SIZE);
printk("dvb_ca adapter %d: Unable to allocate CAM rx buffer :(\n", ca->dvbdev->adapter->num); if (rxbuf == NULL) {
ca->slot_info[slot].slot_state = DVB_CA_SLOTSTATE_INVALID; printk("dvb_ca adapter %d: Unable to allocate CAM rx buffer :(\n", ca->dvbdev->adapter->num);
dvb_ca_en50221_thread_update_delay(ca); ca->slot_info[slot].slot_state = DVB_CA_SLOTSTATE_INVALID;
break; dvb_ca_en50221_thread_update_delay(ca);
break;
}
dvb_ringbuffer_init(&ca->slot_info[slot].rx_buffer, rxbuf, RX_BUFFER_SIZE);
} }
down_write(&ca->slot_info[slot].sem);
dvb_ringbuffer_init(&ca->slot_info[slot].rx_buffer, rxbuf, RX_BUFFER_SIZE);
up_write(&ca->slot_info[slot].sem);
ca->pub->slot_ts_enable(ca->pub, slot); ca->pub->slot_ts_enable(ca->pub, slot);
ca->slot_info[slot].slot_state = DVB_CA_SLOTSTATE_RUNNING; ca->slot_info[slot].slot_state = DVB_CA_SLOTSTATE_RUNNING;
@@ -1148,11 +1135,7 @@ static int dvb_ca_en50221_thread(void *data)
if (!ca->open) if (!ca->open)
continue; continue;
// no need to poll if the CAM supports IRQs // poll slots for data
if (ca->slot_info[slot].da_irq_supported)
break;
// poll mode
pktcount = 0; pktcount = 0;
while ((status = dvb_ca_en50221_read_data(ca, slot, NULL, 0)) > 0) { while ((status = dvb_ca_en50221_read_data(ca, slot, NULL, 0)) > 0) {
if (!ca->open) if (!ca->open)
@@ -1367,12 +1350,13 @@ exit:
/** /**
* Condition for waking up in dvb_ca_en50221_io_read_condition * Condition for waking up in dvb_ca_en50221_io_read_condition
*/ */
static int dvb_ca_en50221_io_read_condition(struct dvb_ca_private *ca, int *result, int *_slot) static int dvb_ca_en50221_io_read_condition(struct dvb_ca_private *ca,
int *result, int *_slot)
{ {
int slot; int slot;
int slot_count = 0; int slot_count = 0;
int idx; int idx;
int fraglen; size_t fraglen;
int connection_id = -1; int connection_id = -1;
int found = 0; int found = 0;
u8 hdr[2]; u8 hdr[2];
@@ -1382,10 +1366,7 @@ static int dvb_ca_en50221_io_read_condition(struct dvb_ca_private *ca, int *resu
if (ca->slot_info[slot].slot_state != DVB_CA_SLOTSTATE_RUNNING) if (ca->slot_info[slot].slot_state != DVB_CA_SLOTSTATE_RUNNING)
goto nextslot; goto nextslot;
down_read(&ca->slot_info[slot].sem);
if (ca->slot_info[slot].rx_buffer.data == NULL) { if (ca->slot_info[slot].rx_buffer.data == NULL) {
up_read(&ca->slot_info[slot].sem);
return 0; return 0;
} }
@@ -1403,10 +1384,7 @@ static int dvb_ca_en50221_io_read_condition(struct dvb_ca_private *ca, int *resu
idx = dvb_ringbuffer_pkt_next(&ca->slot_info[slot].rx_buffer, idx, &fraglen); idx = dvb_ringbuffer_pkt_next(&ca->slot_info[slot].rx_buffer, idx, &fraglen);
} }
if (!found) nextslot:
up_read(&ca->slot_info[slot].sem);
nextslot:
slot = (slot + 1) % ca->slot_count; slot = (slot + 1) % ca->slot_count;
slot_count++; slot_count++;
} }
@@ -1511,8 +1489,7 @@ static ssize_t dvb_ca_en50221_io_read(struct file *file, char __user * buf,
goto exit; goto exit;
status = pktlen; status = pktlen;
exit: exit:
up_read(&ca->slot_info[slot].sem);
return status; return status;
} }
@@ -1544,11 +1521,11 @@ static int dvb_ca_en50221_io_open(struct inode *inode, struct file *file)
for (i = 0; i < ca->slot_count; i++) { for (i = 0; i < ca->slot_count; i++) {
if (ca->slot_info[i].slot_state == DVB_CA_SLOTSTATE_RUNNING) { if (ca->slot_info[i].slot_state == DVB_CA_SLOTSTATE_RUNNING) {
down_write(&ca->slot_info[i].sem);
if (ca->slot_info[i].rx_buffer.data != NULL) { if (ca->slot_info[i].rx_buffer.data != NULL) {
/* it is safe to call this here without locks because
* ca->open == 0. Data is not read in this case */
dvb_ringbuffer_flush(&ca->slot_info[i].rx_buffer); dvb_ringbuffer_flush(&ca->slot_info[i].rx_buffer);
} }
up_write(&ca->slot_info[i].sem);
} }
} }
@@ -1607,7 +1584,6 @@ static unsigned int dvb_ca_en50221_io_poll(struct file *file, poll_table * wait)
dprintk("%s\n", __FUNCTION__); dprintk("%s\n", __FUNCTION__);
if (dvb_ca_en50221_io_read_condition(ca, &result, &slot) == 1) { if (dvb_ca_en50221_io_read_condition(ca, &result, &slot) == 1) {
up_read(&ca->slot_info[slot].sem);
mask |= POLLIN; mask |= POLLIN;
} }
@@ -1619,7 +1595,6 @@ static unsigned int dvb_ca_en50221_io_poll(struct file *file, poll_table * wait)
poll_wait(file, &ca->wait_queue, wait); poll_wait(file, &ca->wait_queue, wait);
if (dvb_ca_en50221_io_read_condition(ca, &result, &slot) == 1) { if (dvb_ca_en50221_io_read_condition(ca, &result, &slot) == 1) {
up_read(&ca->slot_info[slot].sem);
mask |= POLLIN; mask |= POLLIN;
} }
@@ -1709,7 +1684,6 @@ int dvb_ca_en50221_init(struct dvb_adapter *dvb_adapter,
ca->slot_info[i].slot_state = DVB_CA_SLOTSTATE_NONE; ca->slot_info[i].slot_state = DVB_CA_SLOTSTATE_NONE;
atomic_set(&ca->slot_info[i].camchange_count, 0); atomic_set(&ca->slot_info[i].camchange_count, 0);
ca->slot_info[i].camchange_type = DVB_CA_EN50221_CAMCHANGE_REMOVED; ca->slot_info[i].camchange_type = DVB_CA_EN50221_CAMCHANGE_REMOVED;
init_rwsem(&ca->slot_info[i].sem);
} }
if (signal_pending(current)) { if (signal_pending(current)) {
@@ -1729,7 +1703,7 @@ int dvb_ca_en50221_init(struct dvb_adapter *dvb_adapter,
ca->thread_pid = ret; ca->thread_pid = ret;
return 0; return 0;
error: error:
if (ca != NULL) { if (ca != NULL) {
if (ca->dvbdev != NULL) if (ca->dvbdev != NULL)
dvb_unregister_device(ca->dvbdev); dvb_unregister_device(ca->dvbdev);
@@ -1771,6 +1745,9 @@ void dvb_ca_en50221_release(struct dvb_ca_en50221 *pubca)
for (i = 0; i < ca->slot_count; i++) { for (i = 0; i < ca->slot_count; i++) {
dvb_ca_en50221_slot_shutdown(ca, i); dvb_ca_en50221_slot_shutdown(ca, i);
if (ca->slot_info[i].rx_buffer.data != NULL) {
vfree(ca->slot_info[i].rx_buffer.data);
}
} }
kfree(ca->slot_info); kfree(ca->slot_info);
dvb_unregister_device(ca->dvbdev); dvb_unregister_device(ca->dvbdev);