[PATCH 19/29] pcmcia: call pcmcia_{read, write}_cis_mem with ops_mutex held

Dominik Brodowski linux at dominikbrodowski.net
Wed May 19 02:42:55 EDT 2010


This avoids multiple lock takings in several codepaths.

Signed-off-by: Dominik Brodowski <linux at dominikbrodowski.net>
---
 drivers/pcmcia/cistpl.c          |   21 +++++++++------------
 drivers/pcmcia/pcmcia_ioctl.c    |    4 ++++
 drivers/pcmcia/pcmcia_resource.c |   13 ++++++-------
 3 files changed, 19 insertions(+), 19 deletions(-)

diff --git a/drivers/pcmcia/cistpl.c b/drivers/pcmcia/cistpl.c
index e0b09e7..60d428b 100644
--- a/drivers/pcmcia/cistpl.c
+++ b/drivers/pcmcia/cistpl.c
@@ -129,6 +129,8 @@ static void __iomem *set_cis_map(struct pcmcia_socket *s,
 
 /**
  * pcmcia_read_cis_mem() - low-level function to read CIS memory
+ *
+ * must be called with ops_mutex held
  */
 int pcmcia_read_cis_mem(struct pcmcia_socket *s, int attr, u_int addr,
 		 u_int len, void *ptr)
@@ -138,7 +140,6 @@ int pcmcia_read_cis_mem(struct pcmcia_socket *s, int attr, u_int addr,
 
 	dev_dbg(&s->dev, "pcmcia_read_cis_mem(%d, %#x, %u)\n", attr, addr, len);
 
-	mutex_lock(&s->ops_mutex);
 	if (attr & IS_INDIRECT) {
 		/* Indirect accesses use a bunch of special registers at fixed
 		   locations in common memory */
@@ -153,7 +154,6 @@ int pcmcia_read_cis_mem(struct pcmcia_socket *s, int attr, u_int addr,
 		if (!sys) {
 			dev_dbg(&s->dev, "could not map memory\n");
 			memset(ptr, 0xff, len);
-			mutex_unlock(&s->ops_mutex);
 			return -1;
 		}
 
@@ -184,7 +184,6 @@ int pcmcia_read_cis_mem(struct pcmcia_socket *s, int attr, u_int addr,
 			if (!sys) {
 				dev_dbg(&s->dev, "could not map memory\n");
 				memset(ptr, 0xff, len);
-				mutex_unlock(&s->ops_mutex);
 				return -1;
 			}
 			end = sys + s->map_size;
@@ -198,7 +197,6 @@ int pcmcia_read_cis_mem(struct pcmcia_socket *s, int attr, u_int addr,
 			addr = 0;
 		}
 	}
-	mutex_unlock(&s->ops_mutex);
 	dev_dbg(&s->dev, "  %#2.2x %#2.2x %#2.2x %#2.2x ...\n",
 		*(u_char *)(ptr+0), *(u_char *)(ptr+1),
 		*(u_char *)(ptr+2), *(u_char *)(ptr+3));
@@ -209,7 +207,8 @@ int pcmcia_read_cis_mem(struct pcmcia_socket *s, int attr, u_int addr,
 /**
  * pcmcia_write_cis_mem() - low-level function to write CIS memory
  *
- * Probably only useful for writing one-byte registers.
+ * Probably only useful for writing one-byte registers. Must be called
+ * with ops_mutex held.
  */
 void pcmcia_write_cis_mem(struct pcmcia_socket *s, int attr, u_int addr,
 		   u_int len, void *ptr)
@@ -220,7 +219,6 @@ void pcmcia_write_cis_mem(struct pcmcia_socket *s, int attr, u_int addr,
 	dev_dbg(&s->dev,
 		"pcmcia_write_cis_mem(%d, %#x, %u)\n", attr, addr, len);
 
-	mutex_lock(&s->ops_mutex);
 	if (attr & IS_INDIRECT) {
 		/* Indirect accesses use a bunch of special registers at fixed
 		   locations in common memory */
@@ -234,7 +232,6 @@ void pcmcia_write_cis_mem(struct pcmcia_socket *s, int attr, u_int addr,
 				((cis_width) ? MAP_16BIT : 0));
 		if (!sys) {
 			dev_dbg(&s->dev, "could not map memory\n");
-			mutex_unlock(&s->ops_mutex);
 			return; /* FIXME: Error */
 		}
 
@@ -260,7 +257,6 @@ void pcmcia_write_cis_mem(struct pcmcia_socket *s, int attr, u_int addr,
 			sys = set_cis_map(s, card_offset, flags);
 			if (!sys) {
 				dev_dbg(&s->dev, "could not map memory\n");
-				mutex_unlock(&s->ops_mutex);
 				return; /* FIXME: error */
 			}
 
@@ -275,7 +271,6 @@ void pcmcia_write_cis_mem(struct pcmcia_socket *s, int attr, u_int addr,
 			addr = 0;
 		}
 	}
-	mutex_unlock(&s->ops_mutex);
 }
 
 
@@ -314,7 +309,6 @@ static int read_cis_cache(struct pcmcia_socket *s, int attr, u_int addr,
 			return 0;
 		}
 	}
-	mutex_unlock(&s->ops_mutex);
 
 	ret = pcmcia_read_cis_mem(s, attr, addr, len, ptr);
 
@@ -326,11 +320,11 @@ static int read_cis_cache(struct pcmcia_socket *s, int attr, u_int addr,
 			cis->len = len;
 			cis->attr = attr;
 			memcpy(cis->cache, ptr, len);
-			mutex_lock(&s->ops_mutex);
 			list_add(&cis->node, &s->cis_cache);
-			mutex_unlock(&s->ops_mutex);
 		}
 	}
+	mutex_unlock(&s->ops_mutex);
+
 	return ret;
 }
 
@@ -386,6 +380,7 @@ int verify_cis_cache(struct pcmcia_socket *s)
 			   "no memory for verifying CIS\n");
 		return -ENOMEM;
 	}
+	mutex_lock(&s->ops_mutex);
 	list_for_each_entry(cis, &s->cis_cache, node) {
 		int len = cis->len;
 
@@ -395,10 +390,12 @@ int verify_cis_cache(struct pcmcia_socket *s)
 		ret = pcmcia_read_cis_mem(s, cis->attr, cis->addr, len, buf);
 		if (ret || memcmp(buf, cis->cache, len) != 0) {
 			kfree(buf);
+			mutex_unlock(&s->ops_mutex);
 			return -1;
 		}
 	}
 	kfree(buf);
+	mutex_unlock(&s->ops_mutex);
 	return 0;
 }
 
diff --git a/drivers/pcmcia/pcmcia_ioctl.c b/drivers/pcmcia/pcmcia_ioctl.c
index a42a6c7..ef0c5f1 100644
--- a/drivers/pcmcia/pcmcia_ioctl.c
+++ b/drivers/pcmcia/pcmcia_ioctl.c
@@ -301,7 +301,9 @@ static int pccard_get_status(struct pcmcia_socket *s,
 	    (c->IntType & (INT_MEMORY_AND_IO | INT_ZOOMED_VIDEO))) {
 		u_char reg;
 		if (c->CardValues & PRESENT_PIN_REPLACE) {
+			mutex_lock(&s->ops_mutex);
 			pcmcia_read_cis_mem(s, 1, (c->ConfigBase+CISREG_PRR)>>1, 1, &reg);
+			mutex_unlock(&s->ops_mutex);
 			status->CardState |=
 				(reg & PRR_WP_STATUS) ? CS_EVENT_WRITE_PROTECT : 0;
 			status->CardState |=
@@ -315,7 +317,9 @@ static int pccard_get_status(struct pcmcia_socket *s,
 			status->CardState |= CS_EVENT_READY_CHANGE;
 		}
 		if (c->CardValues & PRESENT_EXT_STATUS) {
+			mutex_lock(&s->ops_mutex);
 			pcmcia_read_cis_mem(s, 1, (c->ConfigBase+CISREG_ESR)>>1, 1, &reg);
+			mutex_unlock(&s->ops_mutex);
 			status->CardState |=
 				(reg & ESR_REQ_ATTN) ? CS_EVENT_REQUEST_ATTENTION : 0;
 		}
diff --git a/drivers/pcmcia/pcmcia_resource.c b/drivers/pcmcia/pcmcia_resource.c
index c6419c1..29f91fa 100644
--- a/drivers/pcmcia/pcmcia_resource.c
+++ b/drivers/pcmcia/pcmcia_resource.c
@@ -123,6 +123,7 @@ int pcmcia_access_configuration_register(struct pcmcia_device *p_dev,
 	config_t *c;
 	int addr;
 	u_char val;
+	int ret = 0;
 
 	if (!p_dev || !p_dev->function_config)
 		return -EINVAL;
@@ -139,11 +140,10 @@ int pcmcia_access_configuration_register(struct pcmcia_device *p_dev,
 	}
 
 	addr = (c->ConfigBase + reg->Offset) >> 1;
-	mutex_unlock(&s->ops_mutex);
 
 	switch (reg->Action) {
 	case CS_READ:
-		pcmcia_read_cis_mem(s, 1, addr, 1, &val);
+		ret = pcmcia_read_cis_mem(s, 1, addr, 1, &val);
 		reg->Value = val;
 		break;
 	case CS_WRITE:
@@ -152,10 +152,11 @@ int pcmcia_access_configuration_register(struct pcmcia_device *p_dev,
 		break;
 	default:
 		dev_dbg(&s->dev, "Invalid conf register request\n");
-		return -EINVAL;
+		ret = -EINVAL;
 		break;
 	}
-	return 0;
+	mutex_unlock(&s->ops_mutex);
+	return ret;
 } /* pcmcia_access_configuration_register */
 EXPORT_SYMBOL(pcmcia_access_configuration_register);
 
@@ -436,7 +437,6 @@ int pcmcia_request_configuration(struct pcmcia_device *p_dev,
 		s->socket.io_irq = 0;
 	s->ops->set_socket(s, &s->socket);
 	s->lock_count++;
-	mutex_unlock(&s->ops_mutex);
 
 	/* Set up CIS configuration registers */
 	base = c->ConfigBase = req->ConfigBase;
@@ -485,7 +485,6 @@ int pcmcia_request_configuration(struct pcmcia_device *p_dev,
 
 	/* Configure I/O windows */
 	if (c->state & CONFIG_IO_REQ) {
-		mutex_lock(&s->ops_mutex);
 		iomap.speed = io_speed;
 		for (i = 0; i < MAX_IO_WIN; i++)
 			if (s->io[i].res) {
@@ -504,11 +503,11 @@ int pcmcia_request_configuration(struct pcmcia_device *p_dev,
 				s->ops->set_io_map(s, &iomap);
 				s->io[i].Config++;
 			}
-		mutex_unlock(&s->ops_mutex);
 	}
 
 	c->state |= CONFIG_LOCKED;
 	p_dev->_locked = 1;
+	mutex_unlock(&s->ops_mutex);
 	return 0;
 } /* pcmcia_request_configuration */
 EXPORT_SYMBOL(pcmcia_request_configuration);
-- 
1.6.3.3




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