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

RCS file: /cvs/lvm2/LVM2/lib/filters/filter-sysfs.c,v

retrieving revision 1.17

retrieving revision 1.18

diff -u -r1.17 -r1.18

--- LVM2/lib/filters/filter-sysfs.c	2007/08/22 14:38:16	1.17

+++ LVM2/lib/filters/filter-sysfs.c	2007/10/10 11:31:21	1.18

@@ -20,12 +20,14 @@

 #include <dirent.h>

-static int _locate_sysfs_blocks(const char *proc, char *path, size_t len)

+static int _locate_sysfs_blocks(const char *proc, char *path, size_t len,

+				unsigned *sysfs_depth)

 {

 	char proc_mounts[PATH_MAX];

-	int r = 0;

 	FILE *fp;

 	char *split[4], buffer[PATH_MAX + 16];

+	const char *sys_mnt = NULL;

+	struct stat info;

 	if (!*proc) {

 		log_verbose("No proc filesystem found: skipping sysfs filter");

@@ -46,10 +48,7 @@

 	while (fgets(buffer, sizeof(buffer), fp)) {

 		if (dm_split_words(buffer, 4, 0, split) == 4 &&

 		    !strcmp(split[2], "sysfs")) {

-			if (dm_snprintf(path, len, "%s/%s", split[1],

-					 "block") >= 0) {

-				r = 1;

-			}

+			sys_mnt = split[1];

 			break;

 		}

 	}

@@ -57,7 +56,70 @@

 	if (fclose(fp))

 		log_sys_error("fclose", proc_mounts);

-	return r;

+	if (!sys_mnt) {

+		log_error("Failed to find sysfs mount point");

+		return 0;

+	}

+

+	/*

+	 * unified classification directory for all kernel subsystems

+	 *

+	 * /sys/subsystem/block/devices

+	 * |-- sda -> ../../../devices/pci0000:00/0000:00:1f.2/host0/target0:0:0/0:0:0:0/block/sda

+	 * |-- sda1 -> ../../../devices/pci0000:00/0000:00:1f.2/host0/target0:0:0/0:0:0:0/block/sda/sda1

+	 *  `-- sr0 -> ../../../devices/pci0000:00/0000:00:1f.2/host1/target1:0:0/1:0:0:0/block/sr0

+	 *

+	 */

+	if (dm_snprintf(path, len, "%s/%s", sys_mnt,

+			"subsystem/block/devices") >= 0) {

+		if (!stat(path, &info)) {

+			*sysfs_depth = 0;

+			return 1;

+		}

+	}

+

+	/*

+	 * block subsystem as a class

+	 *

+	 * /sys/class/block

+	 * |-- sda -> ../../devices/pci0000:00/0000:00:1f.2/host0/target0:0:0/0:0:0:0/block/sda

+	 * |-- sda1 -> ../../devices/pci0000:00/0000:00:1f.2/host0/target0:0:0/0:0:0:0/block/sda/sda1

+	 *  `-- sr0 -> ../../devices/pci0000:00/0000:00:1f.2/host1/target1:0:0/1:0:0:0/block/sr0

+	 *

+	 */

+	if (dm_snprintf(path, len, "%s/%s", sys_mnt, "class/block") >= 0) {

+		if (!stat(path, &info)) {

+			*sysfs_depth = 0;

+			return 1;

+		}

+	}

+

+	/*

+	 * old block subsystem layout with nested directories

+	 *

+	 * /sys/block/

+	 * |-- sda

+	 * |   |-- capability

+	 * |   |-- dev

+	 * ...

+	 * |   |-- sda1

+	 * |   |   |-- dev

+	 * ...

+	 * |

+	 * `-- sr0

+	 *     |-- capability

+	 *     |-- dev

+	 * ...

+	 *

+	 */

+	if (dm_snprintf(path, len, "%s/%s", sys_mnt, "block") >= 0) {

+		if (!stat(path, &info)) {

+			*sysfs_depth = 1;

+			return 1;

+		}

+	}

+

+	return 0;

 }

 /*----------------------------------------------------------------

@@ -72,11 +134,14 @@

 struct dev_set {

 	struct dm_pool *mem;

 	const char *sys_block;

+	unsigned sysfs_depth;

 	int initialised;

 	struct entry *slots[SET_BUCKETS];

 };

-static struct dev_set *_dev_set_create(struct dm_pool *mem, const char *sys_block)

+static struct dev_set *_dev_set_create(struct dm_pool *mem,

+				       const char *sys_block,

+				       unsigned sysfs_depth)

 {

 	struct dev_set *ds;

@@ -85,6 +150,7 @@

 	ds->mem = mem;

 	ds->sys_block = dm_pool_strdup(mem, sys_block);

+	ds->sysfs_depth = sysfs_depth;

 	ds->initialised = 0;

 	return ds;

@@ -168,13 +234,13 @@

 /*

  * Recurse through sysfs directories, inserting any devs found.

  */

-static int _read_devs(struct dev_set *ds, const char *dir)

+static int _read_devs(struct dev_set *ds, const char *dir, unsigned sysfs_depth)

 {

         struct dirent *d;

         DIR *dr;

-	unsigned char dtype;

 	struct stat info;

 	char path[PATH_MAX];

+	char file[PATH_MAX];

 	dev_t dev = { 0 };

 	int r = 1;

@@ -194,31 +260,22 @@

 			continue;

 		}

-		dtype = d->d_type;

-

-		if (dtype == DT_UNKNOWN) {

-			if (lstat(path, &info) >= 0) {

-				if (S_ISLNK(info.st_mode))

-					dtype = DT_LNK;

-				else if (S_ISDIR(info.st_mode))

-					dtype = DT_DIR;

-				else if (S_ISREG(info.st_mode))

-					dtype = DT_REG;

-			}

+		/* devices have a "dev" file */

+		if (dm_snprintf(file, sizeof(file), "%s/dev", path) < 0) {

+			log_error("sysfs path name too long: %s in %s",

+				  d->d_name, dir);

+			continue;

 		}

-		if (dtype == DT_DIR) {

-			if (!_read_devs(ds, path)) {

-				r = 0;

-				break;

-			}

+		if (!stat(file, &info)) {

+			/* recurse if we found a device and expect subdirs */

+			if (sysfs_depth)

+				_read_devs(ds, path, sysfs_depth - 1);

+

+			/* add the device we have found */

+			if (_read_dev(file, &dev))

+				_set_insert(ds, dev);

 		}

-

-		if ((dtype == DT_REG && !strcmp(d->d_name, "dev")))

-			if (!_read_dev(path, &dev) || !_set_insert(ds, dev)) {

-				r = 0;

-				break;

-			}

 	}

         if (closedir(dr))

@@ -229,7 +286,7 @@

 static int _init_devs(struct dev_set *ds)

 {

-	if (!_read_devs(ds, ds->sys_block)) {

+	if (!_read_devs(ds, ds->sys_block, ds->sysfs_depth)) {

 		ds->initialised = -1;

 		return 0;

 	}

@@ -267,11 +324,12 @@

 struct dev_filter *sysfs_filter_create(const char *proc)

 {

 	char sys_block[PATH_MAX];

+	unsigned sysfs_depth;

 	struct dm_pool *mem;

 	struct dev_set *ds;

 	struct dev_filter *f;

-	if (!_locate_sysfs_blocks(proc, sys_block, sizeof(sys_block)))

+	if (!_locate_sysfs_blocks(proc, sys_block, sizeof(sys_block), &sysfs_depth))

 		return NULL;

 	if (!(mem = dm_pool_create("sysfs", 256))) {

@@ -279,7 +337,7 @@

 		return NULL;

 	}

-	if (!(ds = _dev_set_create(mem, sys_block))) {

+	if (!(ds = _dev_set_create(mem, sys_block, sysfs_depth))) {

 		log_error("sysfs dev_set creation failed");

 		goto bad;

 	}