Change add_memory_driver_managed() to return the online type (MMOP_*) on success instead of 0. This allows callers to determine the actual online state of the memory after addition, which is important when MMOP_SYSTEM_DEFAULT is used and the actual online type depends on the system default policy.
Update virtio_mem to handle the new return value semantics by checking for rc < 0 to detect errors. Signed-off-by: Gregory Price <[email protected]> --- drivers/dax/kmem.c | 2 +- drivers/virtio/virtio_mem.c | 5 +++-- mm/memory_hotplug.c | 4 +++- 3 files changed, 7 insertions(+), 4 deletions(-) diff --git a/drivers/dax/kmem.c b/drivers/dax/kmem.c index 5e0cf94a9620..d0dd36c536a0 100644 --- a/drivers/dax/kmem.c +++ b/drivers/dax/kmem.c @@ -178,7 +178,7 @@ static int dev_dax_kmem_probe(struct dev_dax *dev_dax) range_len(&range), kmem_name, mhp_flags, MMOP_SYSTEM_DEFAULT); - if (rc) { + if (rc < 0) { dev_warn(dev, "mapping%d: %#llx-%#llx memory add failed\n", i, range.start, range.end); remove_resource(res); diff --git a/drivers/virtio/virtio_mem.c b/drivers/virtio/virtio_mem.c index b1ec8f2b9e31..4decb44f5a43 100644 --- a/drivers/virtio/virtio_mem.c +++ b/drivers/virtio/virtio_mem.c @@ -656,15 +656,16 @@ static int virtio_mem_add_memory(struct virtio_mem *vm, uint64_t addr, rc = add_memory_driver_managed(vm->mgid, addr, size, vm->resource_name, MHP_MERGE_RESOURCE | MHP_NID_IS_MGID, MMOP_SYSTEM_DEFAULT); - if (rc) { + if (rc < 0) { atomic64_sub(size, &vm->offline_size); dev_warn(&vm->vdev->dev, "adding memory failed: %d\n", rc); /* * TODO: Linux MM does not properly clean up yet in all cases * where adding of memory failed - especially on -ENOMEM. */ + return rc; } - return rc; + return 0; } /* diff --git a/mm/memory_hotplug.c b/mm/memory_hotplug.c index 515ff9d18039..41974a1ccb91 100644 --- a/mm/memory_hotplug.c +++ b/mm/memory_hotplug.c @@ -1689,7 +1689,7 @@ EXPORT_SYMBOL_GPL(add_memory); * MMOP_ONLINE_MOVABLE to online with that type, MMOP_OFFLINE to leave offline, * or MMOP_SYSTEM_DEFAULT to use the system default policy. * - * Returns 0 on success, negative error code on failure. + * Returns the online type (MMOP_*) on success, negative error code on failure. */ int add_memory_driver_managed(int nid, u64 start, u64 size, const char *resource_name, mhp_t mhp_flags, @@ -1721,6 +1721,8 @@ int add_memory_driver_managed(int nid, u64 start, u64 size, rc = __add_memory_resource(nid, res, mhp_flags, online_type); if (rc < 0) release_memory_resource(res); + else + rc = online_type; out_unlock: unlock_device_hotplug(); -- 2.52.0
