---

 libmultipath/discovery.c |  109 +++++++++++++++++++++++++++++++++++++----------

 libmultipath/sysfs.c     |   86 +++++++++++++++++++++++++++++++------

 libmultipath/sysfs.h     |    2 

 3 files changed, 161 insertions(+), 36 deletions(-)

Index: multipath-tools-130222/libmultipath/discovery.c

===================================================================

--- multipath-tools-130222.orig/libmultipath/discovery.c

+++ multipath-tools-130222/libmultipath/discovery.c

@@ -162,7 +162,6 @@ declare_sysfs_get_str(cutype);

 declare_sysfs_get_str(vendor);

 declare_sysfs_get_str(model);

 declare_sysfs_get_str(rev);

-declare_sysfs_get_str(state);

 declare_sysfs_get_str(dev);

 int

@@ -315,9 +314,14 @@ static void

 sysfs_set_rport_tmo(struct multipath *mpp, struct path *pp)

 {

 	struct udev_device *rport_dev = NULL;

-	char value[11];

+	char value[16];

 	char rport_id[32];

+	int delay_fast_io_fail = 0;

+	int current_dev_loss = 0;

+	int ret;

+	if (!mpp->dev_loss && mpp->fast_io_fail == MP_FAST_IO_FAIL_UNSET)

+		return;

 	sprintf(rport_id, "rport-%d:%d-%d",

 		pp->sg_id.host_no, pp->sg_id.channel, pp->sg_id.transport_id);

 	rport_dev = udev_device_new_from_subsystem_sysname(conf->udev,

@@ -330,33 +334,85 @@ sysfs_set_rport_tmo(struct multipath *mp

 	condlog(4, "target%d:%d:%d -> %s", pp->sg_id.host_no,

 		pp->sg_id.channel, pp->sg_id.scsi_id, rport_id);

-	snprintf(value, 11, "%u", mpp->dev_loss);

-	if (mpp->dev_loss &&

-	    sysfs_attr_set_value(rport_dev, "dev_loss_tmo", value, 11) <= 0) {

-		if ((mpp->fast_io_fail == MP_FAST_IO_FAIL_UNSET ||

-		     mpp->fast_io_fail == MP_FAST_IO_FAIL_OFF)

-		    && mpp->dev_loss > 600) {

-			condlog(3, "%s: limiting dev_loss_tmo to 600, since "

-				"fast_io_fail is not set", mpp->alias);

-			snprintf(value, 11, "%u", 600);

-			if (sysfs_attr_set_value(rport_dev, "dev_loss_tmo",

-						 value, 11) <= 0)

-				condlog(0, "%s failed to set dev_loss_tmo",

-					mpp->alias);

+	memset(value, 0, 16);

+	if (mpp->fast_io_fail != MP_FAST_IO_FAIL_UNSET) {

+		ret = sysfs_attr_get_value(rport_dev, "dev_loss_tmo",

+					   value, 16);

+		if (ret <= 0) {

+			condlog(0, "%s: failed to read dev_loss_tmo value, "

+				"error %d", rport_id, -ret);

 			goto out;

 		}

+		if (sscanf(value, "%u\n", &current_dev_loss) != 1) {

+			condlog(0, "%s: Cannot parse dev_loss_tmo "

+				"attribute '%s'", rport_id, value);

+			goto out;

+		}

+		if ((mpp->dev_loss &&

+		     mpp->fast_io_fail >= (int)mpp->dev_loss) ||

+	            (!mpp->dev_loss &&

+                     mpp->fast_io_fail >= (int)current_dev_loss)) {

+			condlog(3, "%s: limiting fast_io_fail_tmo to %d, since "

+                        	"it must be less than dev_loss_tmo",

+				rport_id, mpp->dev_loss - 1);

+			if (mpp->dev_loss)

+				mpp->fast_io_fail = mpp->dev_loss - 1;

+			else

+				mpp->fast_io_fail = current_dev_loss - 1;

+		}

+		if (mpp->fast_io_fail >= (int)current_dev_loss)

+			delay_fast_io_fail = 1;

+	}

+	if (mpp->dev_loss > 600 &&

+	    (mpp->fast_io_fail == MP_FAST_IO_FAIL_OFF ||

+             mpp->fast_io_fail == MP_FAST_IO_FAIL_UNSET)) {

+		condlog(3, "%s: limiting dev_loss_tmo to 600, since "

+			"fast_io_fail is unset or off", rport_id);

+		mpp->dev_loss = 600;

 	}

-	if (mpp->fast_io_fail != MP_FAST_IO_FAIL_UNSET){

+	if (mpp->fast_io_fail != MP_FAST_IO_FAIL_UNSET) {

 		if (mpp->fast_io_fail == MP_FAST_IO_FAIL_OFF)

 			sprintf(value, "off");

 		else if (mpp->fast_io_fail == MP_FAST_IO_FAIL_ZERO)

 			sprintf(value, "0");

+		else if (delay_fast_io_fail)

+			snprintf(value, 16, "%u", current_dev_loss - 1);

 		else

-			snprintf(value, 11, "%u", mpp->fast_io_fail);

-		if (sysfs_attr_set_value(rport_dev, "fast_io_fail_tmo",

-					 value, 11) <= 0) {

-			condlog(0, "%s failed to set fast_io_fail_tmo",

-				mpp->alias);

+			snprintf(value, 16, "%u", mpp->fast_io_fail);

+		ret = sysfs_attr_set_value(rport_dev, "fast_io_fail_tmo",

+					   value, strlen(value));

+		if (ret <= 0) {

+			if (ret == -EBUSY)

+				condlog(3, "%s: rport blocked", rport_id);

+			else

+				condlog(0, "%s: failed to set fast_io_fail_tmo to %s, error %d",

+					rport_id, value, -ret);

+			goto out;

+		}

+	}

+	if (mpp->dev_loss) {

+		snprintf(value, 16, "%u", mpp->dev_loss);

+		ret = sysfs_attr_set_value(rport_dev, "dev_loss_tmo",

+					   value, strlen(value));

+		if (ret <= 0) {

+			if (ret == -EBUSY)

+				condlog(3, "%s: rport blocked", rport_id);

+			else

+				condlog(0, "%s: failed to set dev_loss_tmo to %s, error %d",

+					rport_id, value, -ret);

+			goto out;

+		}

+	}

+	if (delay_fast_io_fail) {

+		snprintf(value, 16, "%u", mpp->fast_io_fail);

+		ret = sysfs_attr_set_value(rport_dev, "fast_io_fail_tmo",

+					   value, strlen(value));

+		if (ret <= 0) {

+			if (ret == -EBUSY)

+				condlog(3, "%s: rport blocked", rport_id);

+			else

+				condlog(0, "%s: failed to set fast_io_fail_tmo to %s, error %d",

+					rport_id, value, -ret);

 		}

 	}

 out:

@@ -394,7 +450,7 @@ sysfs_set_session_tmo(struct multipath *

 		} else {

 			snprintf(value, 11, "%u", mpp->fast_io_fail);

 			if (sysfs_attr_set_value(session_dev, "recovery_tmo",

-						 value, 11)) {

+						 value, 11) <= 0) {

 				condlog(3, "%s: Failed to set recovery_tmo, "

 					" error %d", pp->dev, errno);

 			}

@@ -752,6 +808,9 @@ cciss_sysfs_pathinfo (struct path * pp)

 static int

 common_sysfs_pathinfo (struct path * pp)

 {

+	if (!pp)

+		return 1;

+

 	if (!pp->udev) {

 		condlog(4, "%s: udev not initialised", pp->dev);

 		return 1;

@@ -793,7 +852,8 @@ path_offline (struct path * pp)

 		return PATH_DOWN;

 	}

-	if (sysfs_get_state(parent, buff, SCSI_STATE_SIZE))

+	memset(buff, 0x0, SCSI_STATE_SIZE);

+	if (sysfs_attr_get_value(parent, "state", buff, SCSI_STATE_SIZE) <= 0)

 		return PATH_DOWN;

 	condlog(3, "%s: path state = %s", pp->dev, buff);

@@ -983,6 +1043,9 @@ pathinfo (struct path *pp, vector hwtabl

 {

 	int path_state;

+	if (!pp)

+		return 1;

+

 	condlog(3, "%s: mask = 0x%x", pp->dev, mask);

 	/*

Index: multipath-tools-130222/libmultipath/sysfs.c

===================================================================

--- multipath-tools-130222.orig/libmultipath/sysfs.c

+++ multipath-tools-130222/libmultipath/sysfs.c

@@ -38,7 +38,12 @@

 #include "debug.h"

 #include "devmapper.h"

-ssize_t sysfs_attr_set_value(struct udev_device *dev, const char *attr_name,

+/*

+ * When we modify an attribute value we cannot rely on libudev for now,

+ * as libudev lacks the capability to update an attribute value.

+ * So for modified attributes we need to implement our own function.

+ */

+ssize_t sysfs_attr_get_value(struct udev_device *dev, const char *attr_name,

 			     char * value, size_t value_len)

 {

 	char devpath[PATH_SIZE];

@@ -54,28 +59,83 @@ ssize_t sysfs_attr_set_value(struct udev

 	condlog(4, "open '%s'", devpath);

 	if (stat(devpath, &statbuf) != 0) {

 		condlog(4, "stat '%s' failed: %s", devpath, strerror(errno));

-		return 0;

+		return -errno;

 	}

 	/* skip directories */

-	if (S_ISDIR(statbuf.st_mode))

-		return 0;

+	if (S_ISDIR(statbuf.st_mode)) {

+		condlog(4, "%s is a directory", devpath);

+		return -EISDIR;

+	}

 	/* skip non-writeable files */

-	if ((statbuf.st_mode & S_IWUSR) == 0)

+	if ((statbuf.st_mode & S_IRUSR) == 0) {

+		condlog(4, "%s is not readable", devpath);

+		return -EPERM;

+	}

+

+	/* read attribute value */

+	fd = open(devpath, O_RDONLY);

+	if (fd < 0) {

+		condlog(4, "attribute '%s' can not be opened: %s",

+			devpath, strerror(errno));

+		return -errno;

+	}

+	size = read(fd, value, value_len);

+	if (size < 0) {

+		condlog(4, "read from %s failed: %s", devpath, strerror(errno));

+		size = -errno;

+	} else if (size == value_len) {

+		condlog(4, "overflow while reading from %s", devpath);

+		size = 0;

+	}

+

+	close(fd);

+	return size;

+}

+

+ssize_t sysfs_attr_set_value(struct udev_device *dev, const char *attr_name,

+			     char * value, size_t value_len)

+{

+	char devpath[PATH_SIZE];

+	struct stat statbuf;

+	int fd;

+	ssize_t size = -1;

+

+	if (!dev || !attr_name || !value || !value_len)

 		return 0;

+	snprintf(devpath, PATH_SIZE, "%s/%s", udev_device_get_syspath(dev),

+		 attr_name);

+	condlog(4, "open '%s'", devpath);

+	if (stat(devpath, &statbuf) != 0) {

+		condlog(4, "stat '%s' failed: %s", devpath, strerror(errno));

+		return -errno;

+	}

+

+	/* skip directories */

+	if (S_ISDIR(statbuf.st_mode)) {

+		condlog(4, "%s is a directory", devpath);

+		return -EISDIR;

+	}

+

+	/* skip non-writeable files */

+	if ((statbuf.st_mode & S_IWUSR) == 0) {

+		condlog(4, "%s is not writeable", devpath);

+		return -EPERM;

+	}

+

 	/* write attribute value */

 	fd = open(devpath, O_WRONLY);

 	if (fd < 0) {

 		condlog(4, "attribute '%s' can not be opened: %s",

 			devpath, strerror(errno));

-		return 0;

+		return -errno;

 	}

 	size = write(fd, value, value_len);

 	if (size < 0) {

 		condlog(4, "write to %s failed: %s", devpath, strerror(errno));

-		size = 0;

+		size = -errno;

 	} else if (size < value_len) {

 		condlog(4, "tried to write %ld to %s. Wrote %ld",

 			(long)value_len, devpath, (long)size);

@@ -89,14 +149,14 @@ ssize_t sysfs_attr_set_value(struct udev

 int

 sysfs_get_size (struct path *pp, unsigned long long * size)

 {

-	const char * attr;

+	char attr[255];

 	int r;

-	if (!pp->udev)

+	if (!pp->udev || !size)

 		return 1;

-	attr = udev_device_get_sysattr_value(pp->udev, "size");

-	if (!attr) {

+	attr[0] = '\0';

+	if (sysfs_attr_get_value(pp->udev, "size", attr, 255) == 0) {

 		condlog(3, "%s: No size attribute in sysfs", pp->dev);

 		return 1;

 	}

@@ -104,8 +164,8 @@ sysfs_get_size (struct path *pp, unsigne

 	r = sscanf(attr, "%llu\n", size);

 	if (r != 1) {

-		condlog(3, "%s: Cannot parse size attribute '%s'",

-			pp->dev, attr);

+		condlog(3, "%s: Cannot parse size attribute", pp->dev);

+		*size = 0;

 		return 1;

 	}

Index: multipath-tools-130222/libmultipath/sysfs.h

===================================================================

--- multipath-tools-130222.orig/libmultipath/sysfs.h

+++ multipath-tools-130222/libmultipath/sysfs.h

@@ -7,6 +7,8 @@

 ssize_t sysfs_attr_set_value(struct udev_device *dev, const char *attr_name,

 			     char * value, size_t value_len);

+ssize_t sysfs_attr_get_value(struct udev_device *dev, const char *attr_name,

+			     char * value, size_t value_len);

 int sysfs_get_size (struct path *pp, unsigned long long * size);

 int sysfs_check_holders(char * check_devt, char * new_devt);

 #endif