Quoting Sahil Mehta (2016-08-01 12:23:16) > 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 <sme...@linux.vnet.ibm.com> > --- > v2: -use u32s drc_index and count instead of u32 ic[] > in dlpar_memory > v3: -add logic to handle invalid drc_index input > v4: -none > > arch/powerpc/platforms/pseries/hotplug-memory.c | 90 > +++++++++++++++++++++++ > 1 file changed, 90 insertions(+) > > diff --git a/arch/powerpc/platforms/pseries/hotplug-memory.c > b/arch/powerpc/platforms/pseries/hotplug-memory.c > index 2d4ceb3..dd5eb38 100644 > --- a/arch/powerpc/platforms/pseries/hotplug-memory.c > +++ b/arch/powerpc/platforms/pseries/hotplug-memory.c > @@ -503,6 +503,92 @@ static int dlpar_memory_remove_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 = 0; i < end_index; i++) {
Shouldn't this be i = start_index? Otherwise it seems we'd attempt to satisfy the request using LMBs outside of the requested range. > + 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; > + > + 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) > @@ -829,6 +915,10 @@ 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.indexed_count[0]; > + drc_index = hp_elog->_drc_u.indexed_count[1]; > + rc = dlpar_memory_remove_by_ic(count, drc_index, > prop); > } else { > rc = -EINVAL; > } > > _______________________________________________ > Linuxppc-dev mailing list > Linuxppc-dev@lists.ozlabs.org > https://lists.ozlabs.org/listinfo/linuxppc-dev