diff options
Diffstat (limited to 'drivers/nvdimm/bus.c')
| -rw-r--r-- | drivers/nvdimm/bus.c | 25 |
1 files changed, 20 insertions, 5 deletions
diff --git a/drivers/nvdimm/bus.c b/drivers/nvdimm/bus.c index a8b6949a8778..23d4a1728cdf 100644 --- a/drivers/nvdimm/bus.c +++ b/drivers/nvdimm/bus.c @@ -715,7 +715,7 @@ EXPORT_SYMBOL_GPL(nd_cmd_in_size); u32 nd_cmd_out_size(struct nvdimm *nvdimm, int cmd, const struct nd_cmd_desc *desc, int idx, const u32 *in_field, - const u32 *out_field) + const u32 *out_field, unsigned long remainder) { if (idx >= desc->out_num) return UINT_MAX; @@ -727,9 +727,24 @@ u32 nd_cmd_out_size(struct nvdimm *nvdimm, int cmd, return in_field[1]; else if (nvdimm && cmd == ND_CMD_VENDOR && idx == 2) return out_field[1]; - else if (!nvdimm && cmd == ND_CMD_ARS_STATUS && idx == 2) - return out_field[1] - 8; - else if (cmd == ND_CMD_CALL) { + else if (!nvdimm && cmd == ND_CMD_ARS_STATUS && idx == 2) { + /* + * Per table 9-276 ARS Data in ACPI 6.1, out_field[1] is + * "Size of Output Buffer in bytes, including this + * field." + */ + if (out_field[1] < 4) + return 0; + /* + * ACPI 6.1 is ambiguous if 'status' is included in the + * output size. If we encounter an output size that + * overshoots the remainder by 4 bytes, assume it was + * including 'status'. + */ + if (out_field[1] - 8 == remainder) + return remainder; + return out_field[1] - 4; + } else if (cmd == ND_CMD_CALL) { struct nd_cmd_pkg *pkg = (struct nd_cmd_pkg *) in_field; return pkg->nd_size_out; @@ -876,7 +891,7 @@ static int __nd_ioctl(struct nvdimm_bus *nvdimm_bus, struct nvdimm *nvdimm, /* process an output envelope */ for (i = 0; i < desc->out_num; i++) { u32 out_size = nd_cmd_out_size(nvdimm, cmd, desc, i, - (u32 *) in_env, (u32 *) out_env); + (u32 *) in_env, (u32 *) out_env, 0); u32 copy; if (out_size == UINT_MAX) { |