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powerpc/feature-fixups: Refactor entry fixups patching

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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
This commit is contained in:
Christophe Leroy 2022-12-02 09:31:40 +01:00 committed by Michael Ellerman
parent 84ecfe6f38
commit 6076dc349b
1 changed files with 32 additions and 52 deletions
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84
arch/powerpc/lib/feature-fixups.c
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@ -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" :