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Diffstat (limited to 'libsysfs/sysfs_class.c')
-rw-r--r--libsysfs/sysfs_class.c201
1 files changed, 127 insertions, 74 deletions
diff --git a/libsysfs/sysfs_class.c b/libsysfs/sysfs_class.c
index 16eaf6e514..cd86912142 100644
--- a/libsysfs/sysfs_class.c
+++ b/libsysfs/sysfs_class.c
@@ -160,6 +160,11 @@ struct sysfs_class_device *sysfs_open_class_device_path
}
strcpy(cdev->path, path);
+ if ((sysfs_remove_trailing_slash(cdev->path)) != 0) {
+ dprintf("Invalid path to class device %s\n", cdev->path);
+ sysfs_close_class_device(cdev);
+ return NULL;
+ }
set_classdev_classname(cdev);
return cdev;
@@ -179,6 +184,10 @@ struct dlist *sysfs_get_class_devices(struct sysfs_class *cls)
errno = EINVAL;
return NULL;
}
+
+ if (cls->devices != NULL)
+ return cls->devices;
+
if (cls->directory == NULL) {
cls->directory = sysfs_open_directory(cls->path);
if (cls->directory == NULL)
@@ -226,16 +235,16 @@ struct sysfs_class *sysfs_open_class(const unsigned char *name)
dprintf("Sysfs not supported on this system\n");
return NULL;
}
- if (sysfs_trailing_slash(classpath) == 0)
- strcat(classpath, "/");
/*
* We shall now treat "block" also as a class. Hence, check here
* if "name" is "block" and proceed accordingly
*/
if (strcmp(name, SYSFS_BLOCK_NAME) == 0) {
+ strcat(classpath, "/");
strcat(classpath, SYSFS_BLOCK_NAME);
} else {
+ strcat(classpath, "/");
strcat(classpath, SYSFS_CLASS_NAME);
strcat(classpath, "/");
strcat(classpath, name);
@@ -252,6 +261,11 @@ struct sysfs_class *sysfs_open_class(const unsigned char *name)
}
strcpy(cls->name, name);
strcpy(cls->path, classpath);
+ if ((sysfs_remove_trailing_slash(cls->path)) != 0) {
+ dprintf("Invalid path to class device %s\n", cls->path);
+ sysfs_close_class(cls);
+ return NULL;
+ }
return cls;
}
@@ -264,8 +278,6 @@ struct sysfs_class *sysfs_open_class(const unsigned char *name)
struct sysfs_class_device *sysfs_get_class_device(struct sysfs_class *class,
unsigned char *name)
{
- struct dlist *devlist = NULL;
-
if (class == NULL || name == NULL) {
errno = EINVAL;
return NULL;
@@ -273,7 +285,7 @@ struct sysfs_class_device *sysfs_get_class_device(struct sysfs_class *class,
if (class->devices == NULL) {
class->devices = sysfs_get_class_devices(class);
- if (devlist == NULL)
+ if (class->devices == NULL)
return NULL;
}
return (struct sysfs_class_device *)dlist_find_custom(class->devices,
@@ -291,14 +303,21 @@ struct sysfs_device *sysfs_get_classdev_device
(struct sysfs_class_device *clsdev)
{
struct sysfs_link *devlink = NULL;
+ unsigned char devpath[SYSFS_PATH_MAX];
if (clsdev == NULL) {
errno = EINVAL;
return NULL;
}
-
- if (clsdev->sysdevice != NULL)
- return (clsdev->sysdevice);
+ strcpy(devpath, clsdev->path);
+ strcat(devpath, "/device");
+ if ((sysfs_path_is_link(devpath)) != 0) {
+ if (clsdev->sysdevice != NULL) {
+ sysfs_close_device(clsdev->sysdevice);
+ clsdev->sysdevice = NULL;
+ }
+ return NULL;
+ }
if (clsdev->directory == NULL) {
clsdev->directory = sysfs_open_directory(clsdev->path);
@@ -306,8 +325,24 @@ struct sysfs_device *sysfs_get_classdev_device
return NULL;
}
devlink = sysfs_get_directory_link(clsdev->directory, "device");
- if (devlink == NULL)
+ if (devlink == NULL) {
+ if (clsdev->sysdevice != NULL) {
+ dprintf("Device link no longer exists\n");
+ sysfs_close_device(clsdev->sysdevice);
+ clsdev->sysdevice = NULL;
+ }
return NULL;
+ }
+
+ if (clsdev->sysdevice != NULL) {
+ if (!strncmp(devlink->target, clsdev->sysdevice->path,
+ SYSFS_PATH_MAX))
+ /* sysdevice hasn't changed */
+ return (clsdev->sysdevice);
+ else
+ /* come here only if the device link for has changed */
+ sysfs_close_device(clsdev->sysdevice);
+ }
clsdev->sysdevice = sysfs_open_device_path(devlink->target);
if (clsdev->sysdevice == NULL)
@@ -329,31 +364,56 @@ struct sysfs_driver *sysfs_get_classdev_driver
(struct sysfs_class_device *clsdev)
{
struct sysfs_link *drvlink = NULL;
+ unsigned char drvpath[SYSFS_PATH_MAX];
if (clsdev == NULL) {
errno = EINVAL;
return NULL;
}
-
- if (clsdev->driver != NULL)
- return (clsdev->driver);
-
+ strcpy(drvpath, clsdev->path);
+ strcat(drvpath, "/driver");
+ if ((sysfs_path_is_link(drvpath)) != 0) {
+ if (clsdev->driver != NULL) {
+ sysfs_close_driver(clsdev->driver);
+ clsdev->driver = NULL;
+ }
+ return NULL;
+ }
+
if (clsdev->directory == NULL) {
clsdev->directory = sysfs_open_directory(clsdev->path);
if (clsdev->directory == NULL)
return NULL;
}
drvlink = sysfs_get_directory_link(clsdev->directory, "driver");
- if (drvlink != NULL) {
- clsdev->driver = sysfs_open_driver_path(drvlink->target);
- if (clsdev->driver == NULL)
- return NULL;
-
+ if (drvlink == NULL) {
+ if (clsdev->driver != NULL) {
+ dprintf("Driver link no longer exists\n");
+ sysfs_close_driver(clsdev->driver);
+ clsdev->driver = NULL;
+ }
+ return NULL;
+ }
+ if (clsdev->driver != NULL) {
+ if (!strncmp(drvlink->target, clsdev->driver->path,
+ SYSFS_PATH_MAX))
+ /* driver hasn't changed */
+ return (clsdev->driver);
+ else
+ /* come here only if the device link for has changed */
+ sysfs_close_driver(clsdev->driver);
}
+
+ clsdev->driver = sysfs_open_driver_path(drvlink->target);
+ if (clsdev->driver == NULL)
+ return NULL;
+ if (clsdev->sysdevice != NULL)
+ strcpy(clsdev->sysdevice->driver_name, clsdev->driver->name);
+
return (clsdev->driver);
}
-
-/*
+
+/**
* get_blockdev_parent: Get the parent class device for a "block" subsystem
* device if present
* @clsdev: block subsystem class device whose parent needs to be found
@@ -361,48 +421,34 @@ struct sysfs_driver *sysfs_get_classdev_driver
*/
static int get_blockdev_parent(struct sysfs_class_device *clsdev)
{
- unsigned char parent_path[SYSFS_PATH_MAX], value[256], *c = NULL;
-
- memset(parent_path, 0, SYSFS_PATH_MAX);
- strcpy(parent_path, clsdev->path);
+ unsigned char parent_path[SYSFS_PATH_MAX], *c = NULL;
+ strcpy(parent_path, clsdev->path);
c = strstr(parent_path, SYSFS_BLOCK_NAME);
if (c == NULL) {
- dprintf("Class device %s does not belong to BLOCK subsystem",
+ dprintf("Class device %s does not belong to BLOCK subsystem\n",
clsdev->name);
return 1;
}
-
+
c += strlen(SYSFS_BLOCK_NAME);
if (*c == '/')
c++;
else
goto errout;
-
- /* validate whether the given class device is a partition or not */
- if ((strncmp(c, clsdev->name, strlen(clsdev->name))) == 0) {
- dprintf("%s not a partition\n", clsdev->name);
- return 1;
- }
- c = strchr(c, '/');
- if (c == NULL)
- goto errout;
- *c = '\0';
-
- /* Now validate if the parent has the "dev" attribute */
- memset(value, 0, 256);
- strcat(parent_path, "/dev");
- if ((sysfs_read_attribute_value(parent_path, value, 256)) != 0) {
- dprintf("Block device %s does not have a parent\n",
- clsdev->name);
- return 1;
- }
-
- c = strrchr(parent_path, '/');
+
+ /* validate whether the given class device is a partition or not */
+ if ((strncmp(c, clsdev->name, strlen(clsdev->name))) == 0) {
+ dprintf("%s not a partition\n", clsdev->name);
+ return 1;
+ }
+
+ c = strchr(c, '/');
if (c == NULL)
goto errout;
*c = '\0';
+
clsdev->parent = sysfs_open_class_device_path(parent_path);
if (clsdev->parent == NULL) {
dprintf("Error opening the parent class device at %s\n",
@@ -467,13 +513,11 @@ static int get_classdev_path(const unsigned char *classname,
dprintf("Error getting sysfs mount path\n");
return -1;
}
-
- if (sysfs_trailing_slash(path) == 0)
- strcat(path, "/");
-
if (strcmp(classname, SYSFS_BLOCK_NAME) == 0) {
+ strcat(path, "/");
strcat(path, SYSFS_BLOCK_NAME);
} else {
+ strcat(path, "/");
strcat(path, SYSFS_CLASS_NAME);
strcat(path, "/");
strcat(path, classname);
@@ -537,27 +581,41 @@ struct dlist *sysfs_get_classdev_attributes(struct sysfs_class_device *cdev)
return NULL;
}
if (cdev->directory->attributes == NULL) {
- if ((sysfs_read_dir_attributes(cdev->directory)) != 0) {
- dprintf("Error reading attributes for directory %s\n",
- cdev->directory->path);
- return NULL;
- }
- } else {
- if ((sysfs_path_is_dir(cdev->path)) != 0) {
- dprintf("Class device at %s no longer exists\n",
- cdev->path);
- return NULL;
- }
- if ((sysfs_refresh_attributes
- (cdev->directory->attributes)) != 0) {
- dprintf("Error refreshing classdev attributes\n");
+ if ((sysfs_read_dir_attributes(cdev->directory)) != 0)
return NULL;
- }
}
return (cdev->directory->attributes);
}
/**
+ * sysfs_refresh_clsassdev_attributes: refreshes the driver's list of attributes
+ * @clsdev: sysfs_class_device whose attributes to refresh
+ *
+ * NOTE: Upon return, prior references to sysfs_attributes for this classdev
+ * _may_ not be valid
+ *
+ * Returns list of attributes on success and NULL on failure
+ */
+struct dlist *sysfs_refresh_classdev_attributes
+ (struct sysfs_class_device *clsdev)
+{
+ if (clsdev == NULL) {
+ errno = EINVAL;
+ return NULL;
+ }
+
+ if (clsdev->directory == NULL)
+ return (sysfs_get_classdev_attributes(clsdev));
+
+ if ((sysfs_refresh_dir_attributes(clsdev->directory)) != 0) {
+ dprintf("Error refreshing class_device attributes\n");
+ return NULL;
+ }
+
+ return (clsdev->directory->attributes);
+}
+
+/**
* sysfs_get_classdev_attr: searches class device's attributes by name
* @clsdev: class device to look through
* @name: attribute name to get
@@ -597,15 +655,10 @@ struct sysfs_attribute *sysfs_get_classdev_attr
struct sysfs_directory) {
if ((sysfs_path_is_dir(sdir->path)) != 0)
continue;
- if (sdir->attributes == NULL) {
- cur = sysfs_get_directory_attribute(sdir,
- (unsigned char *)name);
- } else {
- if ((sysfs_refresh_attributes
- (sdir->attributes)) == 0)
- cur = sysfs_get_directory_attribute(sdir,
+ cur = sysfs_get_directory_attribute(sdir,
(unsigned char *)name);
- }
+ if (cur == NULL)
+ continue;
}
}
return cur;