diff options
| -rw-r--r-- | drivers/s390/cio/chp.c | 35 | ||||
| -rw-r--r-- | drivers/s390/cio/chp.h | 6 |
2 files changed, 27 insertions, 14 deletions
diff --git a/drivers/s390/cio/chp.c b/drivers/s390/cio/chp.c index 6c9fa15aac7b..b1addd78689d 100644 --- a/drivers/s390/cio/chp.c +++ b/drivers/s390/cio/chp.c @@ -1,7 +1,7 @@ /* * drivers/s390/cio/chp.c * - * Copyright IBM Corp. 1999,2007 + * Copyright IBM Corp. 1999,2010 * Author(s): Cornelia Huck (cornelia.huck@de.ibm.com) * Arnd Bergmann (arndb@de.ibm.com) * Peter Oberparleiter <peter.oberparleiter@de.ibm.com> @@ -241,11 +241,13 @@ static ssize_t chp_status_show(struct device *dev, struct device_attribute *attr, char *buf) { struct channel_path *chp = to_channelpath(dev); + int status; - if (!chp) - return 0; - return (chp_get_status(chp->chpid) ? sprintf(buf, "online\n") : - sprintf(buf, "offline\n")); + mutex_lock(&chp->lock); + status = chp->state; + mutex_unlock(&chp->lock); + + return status ? sprintf(buf, "online\n") : sprintf(buf, "offline\n"); } static ssize_t chp_status_write(struct device *dev, @@ -261,15 +263,18 @@ static ssize_t chp_status_write(struct device *dev, if (!num_args) return count; - if (!strnicmp(cmd, "on", 2) || !strcmp(cmd, "1")) + if (!strnicmp(cmd, "on", 2) || !strcmp(cmd, "1")) { + mutex_lock(&cp->lock); error = s390_vary_chpid(cp->chpid, 1); - else if (!strnicmp(cmd, "off", 3) || !strcmp(cmd, "0")) + mutex_unlock(&cp->lock); + } else if (!strnicmp(cmd, "off", 3) || !strcmp(cmd, "0")) { + mutex_lock(&cp->lock); error = s390_vary_chpid(cp->chpid, 0); - else + mutex_unlock(&cp->lock); + } else error = -EINVAL; return error < 0 ? error : count; - } static DEVICE_ATTR(status, 0644, chp_status_show, chp_status_write); @@ -315,10 +320,12 @@ static ssize_t chp_type_show(struct device *dev, struct device_attribute *attr, char *buf) { struct channel_path *chp = to_channelpath(dev); + u8 type; - if (!chp) - return 0; - return sprintf(buf, "%x\n", chp->desc.desc); + mutex_lock(&chp->lock); + type = chp->desc.desc; + mutex_unlock(&chp->lock); + return sprintf(buf, "%x\n", type); } static DEVICE_ATTR(type, 0444, chp_type_show, NULL); @@ -395,6 +402,7 @@ int chp_new(struct chp_id chpid) chp->state = 1; chp->dev.parent = &channel_subsystems[chpid.cssid]->device; chp->dev.release = chp_release; + mutex_init(&chp->lock); /* Obtain channel path description and fill it in. */ ret = chsc_determine_base_channel_path_desc(chpid, &chp->desc); @@ -464,7 +472,10 @@ void *chp_get_chp_desc(struct chp_id chpid) desc = kmalloc(sizeof(struct channel_path_desc), GFP_KERNEL); if (!desc) return NULL; + + mutex_lock(&chp->lock); memcpy(desc, &chp->desc, sizeof(struct channel_path_desc)); + mutex_unlock(&chp->lock); return desc; } diff --git a/drivers/s390/cio/chp.h b/drivers/s390/cio/chp.h index 26c3d2246176..695ec20f1c59 100644 --- a/drivers/s390/cio/chp.h +++ b/drivers/s390/cio/chp.h @@ -1,7 +1,7 @@ /* * drivers/s390/cio/chp.h * - * Copyright IBM Corp. 2007 + * Copyright IBM Corp. 2007,2010 * Author(s): Peter Oberparleiter <peter.oberparleiter@de.ibm.com> */ @@ -10,6 +10,7 @@ #include <linux/types.h> #include <linux/device.h> +#include <linux/mutex.h> #include <asm/chpid.h> #include "chsc.h" #include "css.h" @@ -40,14 +41,15 @@ static inline int chp_test_bit(u8 *bitmap, int num) struct channel_path { + struct device dev; struct chp_id chpid; + struct mutex lock; /* Serialize access to below members. */ int state; struct channel_path_desc desc; /* Channel-measurement related stuff: */ int cmg; int shared; void *cmg_chars; - struct device dev; }; int chp_get_status(struct chp_id chpid); |