[RFC PATCH v1 25/42] vm_planes: drop unused per-plane vcpu_count

[Sriram Nambakam <snambakam@linux.microsoft.com>]

Under the in-kernel "Option B" secure-plane model the secure plane runs
on plane-0's existing vCPU thread and is left stopped until the first VTL
call, so a plane never owns a distinct set of vCPUs. The vcpu_count field
in struct vm_plane_config (and the matching parse-state copy) is no longer
consulted by anything in the kernel: drop the field, its VCPU_COUNT config
key parsing, its zero-init and its presence check.

No functional change; the value was already unused on the boot path.

Signed-off-by: Sriram Nambakam <snambakam@linux.microsoft.com>
---
 include/linux/vm_planes.h |  1 -
 init/vm_planes.c          | 11 -----------
 2 files changed, 12 deletions(-)

diff --git a/include/linux/vm_planes.h b/include/linux/vm_planes.h
index 47f05fa80039..1130557cf5aa 100644
--- a/include/linux/vm_planes.h
+++ b/include/linux/vm_planes.h
@@ -20,7 +20,6 @@ struct vm_plane_config {
 	phys_addr_t load_offset;
 	phys_addr_t memory_size;
 	phys_addr_t entry_point;
-	unsigned int vcpu_count;
 	unsigned int kernel_format;
 	char kernel[VM_PLANE_KERNEL_NAME_MAX];
 	char cmdline[VM_PLANE_CMDLINE_MAX];
diff --git a/init/vm_planes.c b/init/vm_planes.c
index 274c0015fe76..10c7facdb1af 100644
--- a/init/vm_planes.c
+++ b/init/vm_planes.c
@@ -25,7 +25,6 @@ static bool __initdata enable_vm_planes_requested;
 struct vm_plane_parse_state {
 	phys_addr_t load_offset;
 	phys_addr_t memory_size;
-	unsigned int vcpu_count;
 	unsigned int kernel_format;
 	char kernel[VM_PLANE_KERNEL_NAME_MAX];
 	char cmdline[VM_PLANE_CMDLINE_MAX];
@@ -275,14 +274,6 @@ static int __init parse_plane_cfg_line(const char *line, size_t len,
 		return 0;
 	}
 
-	if (!strcmp(key, "VCPU_COUNT")) {
-		if (parsed_u64 == 0 || parsed_u64 > UINT_MAX)
-			return -EINVAL;
-		plane_cfg[plane_id].vcpu_count = (unsigned int)parsed_u64;
-		state[plane_id].vcpu_count = (unsigned int)parsed_u64;
-		return 0;
-	}
-
 	return -ENOENT;
 }
 
@@ -314,7 +305,6 @@ static int __init parse_vm_planes_kconfig(const char *buf, size_t len,
 	for (i = 0; i < *plane_count; i++) {
 		state[i].load_offset = VM_PLANES_UNSET_VALUE;
 		state[i].memory_size = VM_PLANES_UNSET_VALUE;
-		state[i].vcpu_count = 0;
 		state[i].kernel[0] = '\0';
 		state[i].cmdline[0] = '\0';
 	}
@@ -336,7 +326,6 @@ static int __init parse_vm_planes_kconfig(const char *buf, size_t len,
 	for (i = 1; i < *plane_count; i++) {
 		if (state[i].load_offset == VM_PLANES_UNSET_VALUE ||
 		    state[i].memory_size == VM_PLANES_UNSET_VALUE ||
-		    !state[i].vcpu_count ||
 		    !state[i].kernel[0])
 			return -EINVAL;
 	}
-- 
2.55.0