powerpc/pseries: Implement indexed-count hotplug memory add

Indexed-count add for memory hotplug guarantees that a contiguous block
of <count> lmbs beginning at a specified <drc index> will be assigned,
any LMBs in this range that are not already assigned will be DLPAR added.
Because of Qemu's per-DIMM memory management, the addition of a contiguous
block of memory currently requires a series of individual calls to add
each LMB in the block. Indexed-count add reduces this series of calls to
a single call for the entire block.

Signed-off-by: Sahil Mehta <sahilmehta17@gmail.com>
Signed-off-by: Nathan Fontenot <nfont@linux.vnet.ibm.com>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>

diff --git a/arch/powerpc/include/asm/rtas.h b/arch/powerpc/include/asm/rtas.h
index 076b89247ab58f2f10a534773c560c086b0bd1a0..ec9dd79398ee975a4d343bca6ad91debdefda857 100644 (file)
--- a/arch/powerpc/include/asm/rtas.h
+++ b/arch/powerpc/include/asm/rtas.h
@@ -307,6 +307,7 @@ struct pseries_hp_errorlog {
        union {
                __be32  drc_index;
                __be32  drc_count;
+               struct { __be32 count, index; } ic;
                char    drc_name[1];
        } _drc_u;
 };
@@ -323,6 +324,7 @@ struct pseries_hp_errorlog {
 #define PSERIES_HP_ELOG_ID_DRC_NAME    1
 #define PSERIES_HP_ELOG_ID_DRC_INDEX   2
 #define PSERIES_HP_ELOG_ID_DRC_COUNT   3
+#define PSERIES_HP_ELOG_ID_DRC_IC      4
 
 struct pseries_errorlog *get_pseries_errorlog(struct rtas_error_log *log,
                                              uint16_t section_id);

diff --git a/arch/powerpc/platforms/pseries/dlpar.c b/arch/powerpc/platforms/pseries/dlpar.c
index d3a81e746fc48c3d06b30728cc2c4164487f1b85..193e052fa0dd888fe62b0fc85ac3cb4669b2c249 100644 (file)
--- a/arch/powerpc/platforms/pseries/dlpar.c
+++ b/arch/powerpc/platforms/pseries/dlpar.c
@@ -354,11 +354,17 @@ static int handle_dlpar_errorlog(struct pseries_hp_errorlog *hp_elog)
        switch (hp_elog->id_type) {
        case PSERIES_HP_ELOG_ID_DRC_COUNT:
                hp_elog->_drc_u.drc_count =
-                                       be32_to_cpu(hp_elog->_drc_u.drc_count);
+                               be32_to_cpu(hp_elog->_drc_u.drc_count);
                break;
        case PSERIES_HP_ELOG_ID_DRC_INDEX:
                hp_elog->_drc_u.drc_index =
-                                       be32_to_cpu(hp_elog->_drc_u.drc_index);
+                               be32_to_cpu(hp_elog->_drc_u.drc_index);
+               break;
+       case PSERIES_HP_ELOG_ID_DRC_IC:
+               hp_elog->_drc_u.ic.count =
+                               be32_to_cpu(hp_elog->_drc_u.ic.count);
+               hp_elog->_drc_u.ic.index =
+                               be32_to_cpu(hp_elog->_drc_u.ic.index);
        }
 
        switch (hp_elog->resource) {
@@ -467,7 +473,33 @@ static int dlpar_parse_id_type(char **cmd, struct pseries_hp_errorlog *hp_elog)
        if (!arg)
                return -EINVAL;
 
-       if (sysfs_streq(arg, "index")) {
+       if (sysfs_streq(arg, "indexed-count")) {
+               hp_elog->id_type = PSERIES_HP_ELOG_ID_DRC_IC;
+               arg = strsep(cmd, " ");
+               if (!arg) {
+                       pr_err("No DRC count specified.\n");
+                       return -EINVAL;
+               }
+
+               if (kstrtou32(arg, 0, &count)) {
+                       pr_err("Invalid DRC count specified.\n");
+                       return -EINVAL;
+               }
+
+               arg = strsep(cmd, " ");
+               if (!arg) {
+                       pr_err("No DRC Index specified.\n");
+                       return -EINVAL;
+               }
+
+               if (kstrtou32(arg, 0, &index)) {
+                       pr_err("Invalid DRC Index specified.\n");
+                       return -EINVAL;
+               }
+
+               hp_elog->_drc_u.ic.count = cpu_to_be32(count);
+               hp_elog->_drc_u.ic.index = cpu_to_be32(index);
+       } else if (sysfs_streq(arg, "index")) {
                hp_elog->id_type = PSERIES_HP_ELOG_ID_DRC_INDEX;
                arg = strsep(cmd, " ");
                if (!arg) {

diff --git a/arch/powerpc/platforms/pseries/hotplug-memory.c b/arch/powerpc/platforms/pseries/hotplug-memory.c
index b3b92814ce871a33a7ce2ca4d2acc79559c19046..ad8b3a606a8e92e3ae707996b3a06937d4156f51 100644 (file)
--- a/arch/powerpc/platforms/pseries/hotplug-memory.c
+++ b/arch/powerpc/platforms/pseries/hotplug-memory.c
@@ -779,6 +779,97 @@ static int dlpar_memory_add_by_index(u32 drc_index, struct property *prop)
        return rc;
 }
 
+static int dlpar_memory_add_by_ic(u32 lmbs_to_add, u32 drc_index,
+                                 struct property *prop)
+{
+       struct of_drconf_cell *lmbs;
+       u32 num_lmbs, *p;
+       int i, rc, start_lmb_found;
+       int lmbs_available = 0, start_index = 0, end_index;
+
+       pr_info("Attempting to hot-add %u LMB(s) at index %x\n",
+               lmbs_to_add, drc_index);
+
+       if (lmbs_to_add == 0)
+               return -EINVAL;
+
+       p = prop->value;
+       num_lmbs = *p++;
+       lmbs = (struct of_drconf_cell *)p;
+       start_lmb_found = 0;
+
+       /* Navigate to drc_index */
+       while (start_index < num_lmbs) {
+               if (lmbs[start_index].drc_index == drc_index) {
+                       start_lmb_found = 1;
+                       break;
+               }
+
+               start_index++;
+       }
+
+       if (!start_lmb_found)
+               return -EINVAL;
+
+       end_index = start_index + lmbs_to_add;
+
+       /* Validate that the LMBs in this range are not reserved */
+       for (i = start_index; i < end_index; i++) {
+               if (lmbs[i].flags & DRCONF_MEM_RESERVED)
+                       break;
+
+               lmbs_available++;
+       }
+
+       if (lmbs_available < lmbs_to_add)
+               return -EINVAL;
+
+       for (i = start_index; i < end_index; i++) {
+               if (lmbs[i].flags & DRCONF_MEM_ASSIGNED)
+                       continue;
+
+               rc = dlpar_acquire_drc(lmbs[i].drc_index);
+               if (rc)
+                       break;
+
+               rc = dlpar_add_lmb(&lmbs[i]);
+               if (rc) {
+                       dlpar_release_drc(lmbs[i].drc_index);
+                       break;
+               }
+
+               lmbs[i].reserved = 1;
+       }
+
+       if (rc) {
+               pr_err("Memory indexed-count-add failed, removing any added LMBs\n");
+
+               for (i = start_index; i < end_index; i++) {
+                       if (!lmbs[i].reserved)
+                               continue;
+
+                       rc = dlpar_remove_lmb(&lmbs[i]);
+                       if (rc)
+                               pr_err("Failed to remove LMB, drc index %x\n",
+                                      be32_to_cpu(lmbs[i].drc_index));
+                       else
+                               dlpar_release_drc(lmbs[i].drc_index);
+               }
+               rc = -EINVAL;
+       } else {
+               for (i = start_index; i < end_index; i++) {
+                       if (!lmbs[i].reserved)
+                               continue;
+
+                       pr_info("Memory at %llx (drc index %x) was hot-added\n",
+                               lmbs[i].base_addr, lmbs[i].drc_index);
+                       lmbs[i].reserved = 0;
+               }
+       }
+
+       return rc;
+}
+
 int dlpar_memory(struct pseries_hp_errorlog *hp_elog)
 {
        struct device_node *dn;
@@ -786,9 +877,6 @@ int dlpar_memory(struct pseries_hp_errorlog *hp_elog)
        u32 count, drc_index;
        int rc;
 
-       count = hp_elog->_drc_u.drc_count;
-       drc_index = hp_elog->_drc_u.drc_index;
-
        lock_device_hotplug();
 
        dn = of_find_node_by_path("/ibm,dynamic-reconfiguration-memory");
@@ -805,22 +893,35 @@ int dlpar_memory(struct pseries_hp_errorlog *hp_elog)
 
        switch (hp_elog->action) {
        case PSERIES_HP_ELOG_ACTION_ADD:
-               if (hp_elog->id_type == PSERIES_HP_ELOG_ID_DRC_COUNT)
+               if (hp_elog->id_type == PSERIES_HP_ELOG_ID_DRC_COUNT) {
+                       count = hp_elog->_drc_u.drc_count;
                        rc = dlpar_memory_add_by_count(count, prop);
-               else if (hp_elog->id_type == PSERIES_HP_ELOG_ID_DRC_INDEX)
+               } else if (hp_elog->id_type == PSERIES_HP_ELOG_ID_DRC_INDEX) {
+                       drc_index = hp_elog->_drc_u.drc_index;
                        rc = dlpar_memory_add_by_index(drc_index, prop);
-               else
+               } else if (hp_elog->id_type == PSERIES_HP_ELOG_ID_DRC_IC) {
+                       count = hp_elog->_drc_u.ic.count;
+                       drc_index = hp_elog->_drc_u.ic.index;
+                       rc = dlpar_memory_add_by_ic(count, drc_index, prop);
+               } else {
                        rc = -EINVAL;
+               }
+
                break;
        case PSERIES_HP_ELOG_ACTION_REMOVE:
-               if (hp_elog->id_type == PSERIES_HP_ELOG_ID_DRC_COUNT)
+               if (hp_elog->id_type == PSERIES_HP_ELOG_ID_DRC_COUNT) {
+                       count = hp_elog->_drc_u.drc_count;
                        rc = dlpar_memory_remove_by_count(count, prop);
-               else if (hp_elog->id_type == PSERIES_HP_ELOG_ID_DRC_INDEX)
+               } else if (hp_elog->id_type == PSERIES_HP_ELOG_ID_DRC_INDEX) {
+                       drc_index = hp_elog->_drc_u.drc_index;
                        rc = dlpar_memory_remove_by_index(drc_index, prop);
-               else
+               } else {
                        rc = -EINVAL;
+               }
+
                break;
        case PSERIES_HP_ELOG_ACTION_READD:
+               drc_index = hp_elog->_drc_u.drc_index;
                rc = dlpar_memory_readd_by_index(drc_index, prop);
                break;
        default: