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-rw-r--r--libblkid/sysfs2.c119
1 files changed, 119 insertions, 0 deletions
diff --git a/libblkid/sysfs2.c b/libblkid/sysfs2.c
new file mode 100644
index 000000000..a04b20a37
--- /dev/null
+++ b/libblkid/sysfs2.c
@@ -0,0 +1,119 @@
+/*
+ * sysfs based topology -- gathers topology information from Linux sysfs
+ *
+ * Copyright (C) 2009 Karel Zak <kzak@redhat.com>
+ *
+ * This file may be redistributed under the terms of the
+ * GNU Lesser General Public License.
+ *
+ * For more information see Linux kernel Documentation/ABI/testing/sysfs-block.
+ */
+#include <stdio.h>
+#include <string.h>
+#include <stdlib.h>
+#include <inttypes.h>
+#include <sys/types.h>
+#include <sys/stat.h>
+#include <unistd.h>
+#include <errno.h>
+
+#include "sysfs.h"
+#include "topology.h"
+
+/*
+ * Sysfs topology values (since 2.6.31, May 2009).
+ */
+static struct topology_val {
+
+ /* /sys/dev/block/<maj>:<min>/<ATTR> */
+ const char *attr;
+
+ /* functions to set probing resut */
+ int (*set_ulong)(blkid_probe, unsigned long);
+ int (*set_int)(blkid_probe, int);
+
+} topology_vals[] = {
+ { "alignment_offset", NULL, blkid_topology_set_alignment_offset },
+ { "queue/minimum_io_size", blkid_topology_set_minimum_io_size },
+ { "queue/optimal_io_size", blkid_topology_set_optimal_io_size },
+ { "queue/physical_block_size", blkid_topology_set_physical_sector_size },
+};
+
+static int probe_sysfs_tp(blkid_probe pr,
+ const struct blkid_idmag *mag __attribute__((__unused__)))
+{
+ dev_t dev, disk = 0;
+ int rc;
+ struct sysfs_cxt sysfs = UL_SYSFSCXT_EMPTY,
+ parent = UL_SYSFSCXT_EMPTY;
+ size_t i, count = 0;
+
+ dev = blkid_probe_get_devno(pr);
+ if (!dev || sysfs_init(&sysfs, dev, NULL) != 0)
+ return 1;
+
+ rc = 1; /* nothing (default) */
+
+ for (i = 0; i < ARRAY_SIZE(topology_vals); i++) {
+ struct topology_val *val = &topology_vals[i];
+ int ok = sysfs_has_attribute(&sysfs, val->attr);
+
+ rc = 1; /* nothing */
+
+ if (!ok) {
+ if (!disk) {
+ /*
+ * Read atrributes from "disk" if the current
+ * device is a partition.
+ */
+ disk = blkid_probe_get_wholedisk_devno(pr);
+ if (disk && disk != dev) {
+ if (sysfs_init(&parent, disk, NULL) != 0)
+ goto done;
+
+ sysfs.parent = &parent;
+ ok = sysfs_has_attribute(&sysfs,
+ val->attr);
+ }
+ }
+ if (!ok)
+ continue; /* attribute does not exist */
+ }
+
+ if (val->set_ulong) {
+ uint64_t data;
+
+ if (sysfs_read_u64(&sysfs, val->attr, &data) != 0)
+ continue;
+ rc = val->set_ulong(pr, (unsigned long) data);
+
+ } else if (val->set_int) {
+ int64_t data;
+
+ if (sysfs_read_s64(&sysfs, val->attr, &data) != 0)
+ continue;
+ rc = val->set_int(pr, (int) data);
+ }
+
+ if (rc < 0)
+ goto done; /* error */
+ if (rc == 0)
+ count++;
+ }
+
+done:
+ sysfs_deinit(&sysfs);
+ sysfs_deinit(&parent);
+
+ if (count)
+ return 0; /* success */
+ return rc; /* error or nothing */
+}
+
+const struct blkid_idinfo sysfs_tp_idinfo =
+{
+ .name = "sysfs",
+ .probefunc = probe_sysfs_tp,
+ .magics = BLKID_NONE_MAGIC
+};
+