From d0f7e5b4a0a1b83e515c9fd894d74ed36d7da5c1 Mon Sep 17 00:00:00 2001
From: Karel Zak <kzak@redhat.com>
Date: Tue, 23 Oct 2012 10:57:59 +0200
Subject: [PATCH] include/sysfs: add SCSI host:channel:target:lun support

Signed-off-by: Karel Zak <kzak@redhat.com>
---
 include/sysfs.h    | 11 +++++++++++
 lib/sysfs.c        | 42 +++++++++++++++++++++++++++++++++++++++---
 misc-utils/lsblk.c | 25 ++-----------------------
 3 files changed, 52 insertions(+), 26 deletions(-)

diff --git a/include/sysfs.h b/include/sysfs.h
index 9e47a5571..10875d421 100644
--- a/include/sysfs.h
+++ b/include/sysfs.h
@@ -21,6 +21,13 @@ struct sysfs_cxt {
 	int	dir_fd;		/* /sys/block/<name> */
 	char	*dir_path;
 	struct sysfs_cxt *parent;
+
+	unsigned int	scsi_host,
+			scsi_channel,
+			scsi_target,
+			scsi_lun;
+
+	unsigned int	has_hctl : 1;
 };
 
 #define UL_SYSFSCXT_EMPTY { 0, -1, NULL, NULL }
@@ -65,4 +72,8 @@ extern int sysfs_is_partition_dirent(DIR *dir, struct dirent *d,
 
 extern int sysfs_devno_to_wholedisk(dev_t dev, char *diskname,
             size_t len, dev_t *diskdevno);
+
+extern int sysfs_scsi_get_hctl(struct sysfs_cxt *cxt, int *h,
+			       int *c, int *t, int *l);
+
 #endif /* UTIL_LINUX_SYSFS_H */
diff --git a/lib/sysfs.c b/lib/sysfs.c
index 1384acda6..4cb6284ca 100644
--- a/lib/sysfs.c
+++ b/lib/sysfs.c
@@ -173,10 +173,9 @@ void sysfs_deinit(struct sysfs_cxt *cxt)
 	       close(cxt->dir_fd);
 	free(cxt->dir_path);
 
-	cxt->devno = 0;
+	memset(cxt, 0, sizeof(*cxt));
+
 	cxt->dir_fd = -1;
-	cxt->parent = NULL;
-	cxt->dir_path = NULL;
 }
 
 int sysfs_stat(struct sysfs_cxt *cxt, const char *attr, struct stat *st)
@@ -636,6 +635,43 @@ err:
     return -1;
 }
 
+
+int sysfs_scsi_get_hctl(struct sysfs_cxt *cxt, int *h, int *c, int *t, int *l)
+{
+	char buf[PATH_MAX], *hctl;
+	ssize_t len;
+
+	if (!cxt)
+		return -EINVAL;
+	if (cxt->has_hctl)
+		goto done;
+
+	len = sysfs_readlink(cxt, "device", buf, sizeof(buf));
+	if (len < 0)
+		return len;
+
+	buf[len] = '\0';
+	hctl = strrchr(buf, '/') + 1;
+	if (!hctl)
+		return -1;
+
+	if (sscanf(hctl, "%d:%d:%d:%d", &cxt->scsi_host, &cxt->scsi_channel,
+				&cxt->scsi_target, &cxt->scsi_lun) != 4)
+		return -1;
+
+	cxt->has_hctl = 1;
+done:
+	if (h)
+		*h = cxt->scsi_host;
+	if (c)
+		*c = cxt->scsi_channel;
+	if (t)
+		*t = cxt->scsi_target;
+	if (l)
+		*l = cxt->scsi_lun;
+	return 0;
+}
+
 #ifdef TEST_PROGRAM_SYSFS
 #include <errno.h>
 #include <err.h>
diff --git a/misc-utils/lsblk.c b/misc-utils/lsblk.c
index 547723c68..c3803d826 100644
--- a/misc-utils/lsblk.c
+++ b/misc-utils/lsblk.c
@@ -577,27 +577,6 @@ static char *get_type(struct blkdev_cxt *cxt)
 	return res;
 }
 
-/* H:C:T:L - Host:Channel:Target:LUN */
-static int get_hctl(struct blkdev_cxt *cxt, int *h, int *c, int *t, int *l)
-{
-	char buf[PATH_MAX], *hctl;
-	ssize_t len;
-
-	len = sysfs_readlink(&cxt->sysfs, "device", buf, sizeof(buf));
-	if (len < 0)
-		return 0;
-
-	buf[len] = '\0';
-	hctl = strrchr(buf, '/') + 1;
-	if (!hctl)
-		return 0;
-
-	if (sscanf(hctl, "%d:%d:%d:%d", h, c, t, l) != 4)
-		return 0;
-
-	return 1;
-}
-
 static char *_sysfs_host_string(const char *type, int host, const char *attr)
 {
 	char path[PATH_MAX], tmp[64] = {0};
@@ -671,7 +650,7 @@ static char *get_transport(struct blkdev_cxt *cxt)
 	int host, channel, target, lun;
 	char *attr;
 
-	if (!get_hctl(cxt, &host, &channel, &target, &lun))
+	if (sysfs_scsi_get_hctl(&cxt->sysfs, &host, &channel, &target, &lun) != 0)
 		return NULL;
 
 	/* SPI - Serial Peripheral Interface */
@@ -923,7 +902,7 @@ static void set_tt_data(struct blkdev_cxt *cxt, int col, int id, struct tt_line
 	case COL_HCTL:
 	{
 		int h, c, t, l;
-		if (get_hctl(cxt, &h, &c, &t, &l)) {
+		if (sysfs_scsi_get_hctl(&cxt->sysfs, &h, &c, &t, &l) == 0) {
 			snprintf(buf, sizeof(buf), "%d:%d:%d:%d", h, c, t, l);
 			tt_line_set_data(ln, col, xstrdup(buf));
 		}