nagai/kernel
3
0
Fork 0
forked from mirrors/linux
Code Pull requests Activity

powerpc/pseries: Implement indexed-count hotplug memory remove

Browse source 
Indexed-count remove for memory hotplug guarantees that a contiguous block
of <count> lmbs beginning at a specified <index> will be unassigned (NOT
that <count> lmbs will be removed). Because of Qemu's per-DIMM memory
management, the removal of a contiguous block of memory currently
requires a series of individual calls. Indexed-count remove reduces
this series into a single call.

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>
This commit is contained in:
Sahil Mehta 2017-02-15 13:46:18 -05:00 committed by Michael Ellerman
parent 333f7b7686
commit 753843471c
1 changed files with 98 additions and 0 deletions
repo.diff.show_diff_stats Download patch file Download diff file Expand all files Collapse all files

98
arch/powerpc/platforms/pseries/hotplug-memory.c
View file

@ -601,6 +601,94 @@ static int dlpar_memory_readd_by_index(u32 drc_index, struct property *prop)
return rc;
}
static int dlpar_memory_remove_by_ic(u32 lmbs_to_remove, 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-remove %u LMB(s) at %x\n",
lmbs_to_remove, drc_index);
if (lmbs_to_remove == 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_remove;
/* Validate that there are enough LMBs to satisfy the request */
for (i = start_index; i < end_index; i++) {
if (lmbs[i].flags & DRCONF_MEM_RESERVED)
break;
lmbs_available++;
}
if (lmbs_available < lmbs_to_remove)
return -EINVAL;
for (i = start_index; i < end_index; i++) {
if (!(lmbs[i].flags & DRCONF_MEM_ASSIGNED))
continue;
rc = dlpar_remove_lmb(&lmbs[i]);
if (rc)
break;
lmbs[i].reserved = 1;
}
if (rc) {
pr_err("Memory indexed-count-remove failed, adding any removed LMBs\n");
for (i = start_index; i < end_index; i++) {
if (!lmbs[i].reserved)
continue;
rc = dlpar_add_lmb(&lmbs[i]);
if (rc)
pr_err("Failed to add LMB, drc index %x\n",
be32_to_cpu(lmbs[i].drc_index));
lmbs[i].reserved = 0;
}
rc = -EINVAL;
} else {
for (i = start_index; i < end_index; i++) {
if (!lmbs[i].reserved)
continue;
dlpar_release_drc(lmbs[i].drc_index);
pr_info("Memory at %llx (drc index %x) was hot-removed\n",
lmbs[i].base_addr, lmbs[i].drc_index);
lmbs[i].reserved = 0;
}
}
return rc;
}
#else
static inline int pseries_remove_memblock(unsigned long base,
unsigned int memblock_size)
@ -632,6 +720,12 @@ static int dlpar_memory_readd_by_index(u32 drc_index, struct property *prop)
{
return -EOPNOTSUPP;
}
static int dlpar_memory_remove_by_ic(u32 lmbs_to_remove, u32 drc_index,
struct property *prop)
{
return -EOPNOTSUPP;
}
#endif /* CONFIG_MEMORY_HOTREMOVE */
static int dlpar_add_lmb(struct of_drconf_cell *lmb)
@ -915,6 +1009,10 @@ int dlpar_memory(struct pseries_hp_errorlog *hp_elog)
} 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 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_remove_by_ic(count, drc_index, prop);
} else {
rc = -EINVAL;
}