edac: Create a dimm struct and move the labels into it

The way a DIMM is currently represented implies that they're
linked into a per-csrow struct. However, some drivers don't see
csrows, as they're ridden behind some chip like the AMB's
on FBDIMM's, for example.

This forced drivers to fake^Wvirtualize a csrow struct, and to create
a mess under csrow/channel original's concept.

Move the DIMM labels into a per-DIMM struct, and add there
the real location of the socket, in terms of csrow/channel.
Latter patches will modify the location to properly represent the
memory architecture.

All other drivers will use a per-csrow type of location.
Some of those drivers will require a latter conversion, as
they also fake the csrows internally.

TODO: While this patch doesn't change the existing behavior, on
csrows-based memory controllers, a csrow/channel pair points to a memory
rank. There's a known bug at the EDAC core that allows having different
labels for the same DIMM, if it has more than one rank. A latter patch
is need to merge the several ranks for a DIMM into the same dimm_info
struct, in order to avoid having different labels for the same DIMM.

The edac_mc_alloc() will now contain a per-dimm initialization loop that
will be changed by latter patches in order to match other types of
memory architectures.

Reviewed-by: Aristeu Rozanski <arozansk@redhat.com>
Reviewed-by: Borislav Petkov <borislav.petkov@amd.com>
Cc: Doug Thompson <norsk5@yahoo.com>
Cc: Ranganathan Desikan <ravi@jetztechnologies.com>
Cc: "Arvind R." <arvino55@gmail.com>
Cc: "Niklas Söderlund" <niklas.soderlund@ericsson.com>
Signed-off-by: Mauro Carvalho Chehab <mchehab@redhat.com>
diff --git a/drivers/edac/edac_mc_sysfs.c b/drivers/edac/edac_mc_sysfs.c
index e9a28f5..af66b22 100644
--- a/drivers/edac/edac_mc_sysfs.c
+++ b/drivers/edac/edac_mc_sysfs.c
@@ -170,11 +170,11 @@
 				char *data, int channel)
 {
 	/* if field has not been initialized, there is nothing to send */
-	if (!csrow->channels[channel].label[0])
+	if (!csrow->channels[channel].dimm->label[0])
 		return 0;
 
 	return snprintf(data, EDAC_MC_LABEL_LEN, "%s\n",
-			csrow->channels[channel].label);
+			csrow->channels[channel].dimm->label);
 }
 
 static ssize_t channel_dimm_label_store(struct csrow_info *csrow,
@@ -184,8 +184,8 @@
 	ssize_t max_size = 0;
 
 	max_size = min((ssize_t) count, (ssize_t) EDAC_MC_LABEL_LEN - 1);
-	strncpy(csrow->channels[channel].label, data, max_size);
-	csrow->channels[channel].label[max_size] = '\0';
+	strncpy(csrow->channels[channel].dimm->label, data, max_size);
+	csrow->channels[channel].dimm->label[max_size] = '\0';
 
 	return max_size;
 }
@@ -952,9 +952,8 @@
 	/* CSROW error: backout what has already been registered,  */
 fail1:
 	for (i--; i >= 0; i--) {
-		if (csrow->nr_pages > 0) {
+		if (mci->csrows[i].nr_pages > 0)
 			kobject_put(&mci->csrows[i].kobj);
-		}
 	}
 
 	/* remove the mci instance's attributes, if any */