powerpc/feature-fixups: Refactor entry fixups patching

Several fonctions have the same loop for patching instructions.

Introduce function do_patch_entry_fixups() to refactor those loops.

Signed-off-by: Christophe Leroy <christophe.leroy@csgroup.eu>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Link: https://lore.kernel.org/r/79eeff7b20a98f7136da5f79b1f7c436928f27f3.1669969781.git.christophe.leroy@csgroup.eu

diff --git a/arch/powerpc/lib/feature-fixups.c b/arch/powerpc/lib/feature-fixups.c
index 31f40f5..93b3f8e 100644 (file)
--- a/arch/powerpc/lib/feature-fixups.c
+++ b/arch/powerpc/lib/feature-fixups.c
@@ -118,9 +118,33 @@ void do_feature_fixups(unsigned long value, void *fixup_start, void *fixup_end)
 }
 
 #ifdef CONFIG_PPC_BOOK3S_64
+static int do_patch_entry_fixups(long *start, long *end, unsigned int *instrs,
+                                bool do_fallback, void *fallback)
+{
+       int i;
+
+       for (i = 0; start < end; start++, i++) {
+               unsigned int *dest = (void *)start + *start;
+
+               pr_devel("patching dest %lx\n", (unsigned long)dest);
+
+               // See comment in do_entry_flush_fixups() RE order of patching
+               if (do_fallback) {
+                       patch_instruction(dest, ppc_inst(instrs[0]));
+                       patch_instruction(dest + 2, ppc_inst(instrs[2]));
+                       patch_branch(dest + 1, (unsigned long)fallback, BRANCH_SET_LINK);
+               } else {
+                       patch_instruction(dest + 1, ppc_inst(instrs[1]));
+                       patch_instruction(dest + 2, ppc_inst(instrs[2]));
+                       patch_instruction(dest, ppc_inst(instrs[0]));
+               }
+       }
+       return i;
+}
+
 static void do_stf_entry_barrier_fixups(enum stf_barrier_type types)
 {
-       unsigned int instrs[3], *dest;
+       unsigned int instrs[3];
        long *start, *end;
        int i;
 
@@ -144,23 +168,8 @@ static void do_stf_entry_barrier_fixups(enum stf_barrier_type types)
                instrs[i++] = PPC_RAW_ORI(_R31, _R31, 0); /* speculation barrier */
        }
 
-       for (i = 0; start < end; start++, i++) {
-               dest = (void *)start + *start;
-
-               pr_devel("patching dest %lx\n", (unsigned long)dest);
-
-               // See comment in do_entry_flush_fixups() RE order of patching
-               if (types & STF_BARRIER_FALLBACK) {
-                       patch_instruction(dest, ppc_inst(instrs[0]));
-                       patch_instruction(dest + 2, ppc_inst(instrs[2]));
-                       patch_branch(dest + 1,
-                                    (unsigned long)&stf_barrier_fallback, BRANCH_SET_LINK);
-               } else {
-                       patch_instruction(dest + 1, ppc_inst(instrs[1]));
-                       patch_instruction(dest + 2, ppc_inst(instrs[2]));
-                       patch_instruction(dest, ppc_inst(instrs[0]));
-               }
-       }
+       i = do_patch_entry_fixups(start, end, instrs, types & STF_BARRIER_FALLBACK,
+                                 &stf_barrier_fallback);
 
        printk(KERN_DEBUG "stf-barrier: patched %d entry locations (%s barrier)\n", i,
                (types == STF_BARRIER_NONE)                  ? "no" :
@@ -325,7 +334,7 @@ void do_uaccess_flush_fixups(enum l1d_flush_type types)
 static int __do_entry_flush_fixups(void *data)
 {
        enum l1d_flush_type types = *(enum l1d_flush_type *)data;
-       unsigned int instrs[3], *dest;
+       unsigned int instrs[3];
        long *start, *end;
        int i;
 
@@ -375,42 +384,13 @@ static int __do_entry_flush_fixups(void *data)
 
        start = PTRRELOC(&__start___entry_flush_fixup);
        end = PTRRELOC(&__stop___entry_flush_fixup);
-       for (i = 0; start < end; start++, i++) {
-               dest = (void *)start + *start;
-
-               pr_devel("patching dest %lx\n", (unsigned long)dest);
-
-               if (types == L1D_FLUSH_FALLBACK) {
-                       patch_instruction(dest, ppc_inst(instrs[0]));
-                       patch_instruction(dest + 2, ppc_inst(instrs[2]));
-                       patch_branch(dest + 1,
-                                    (unsigned long)&entry_flush_fallback, BRANCH_SET_LINK);
-               } else {
-                       patch_instruction(dest + 1, ppc_inst(instrs[1]));
-                       patch_instruction(dest + 2, ppc_inst(instrs[2]));
-                       patch_instruction(dest, ppc_inst(instrs[0]));
-               }
-       }
+       i = do_patch_entry_fixups(start, end, instrs, types == L1D_FLUSH_FALLBACK,
+                                 &entry_flush_fallback);
 
        start = PTRRELOC(&__start___scv_entry_flush_fixup);
        end = PTRRELOC(&__stop___scv_entry_flush_fixup);
-       for (; start < end; start++, i++) {
-               dest = (void *)start + *start;
-
-               pr_devel("patching dest %lx\n", (unsigned long)dest);
-
-               if (types == L1D_FLUSH_FALLBACK) {
-                       patch_instruction(dest, ppc_inst(instrs[0]));
-                       patch_instruction(dest + 2, ppc_inst(instrs[2]));
-                       patch_branch(dest + 1,
-                                    (unsigned long)&scv_entry_flush_fallback, BRANCH_SET_LINK);
-               } else {
-                       patch_instruction(dest + 1, ppc_inst(instrs[1]));
-                       patch_instruction(dest + 2, ppc_inst(instrs[2]));
-                       patch_instruction(dest, ppc_inst(instrs[0]));
-               }
-       }
-
+       i += do_patch_entry_fixups(start, end, instrs, types == L1D_FLUSH_FALLBACK,
+                                  &scv_entry_flush_fallback);
 
        printk(KERN_DEBUG "entry-flush: patched %d locations (%s flush)\n", i,
                (types == L1D_FLUSH_NONE)       ? "no" :