@@ -106,12 +106,8 @@ static unsigned long find_trampoline_placement(void)
return bios_start - TRAMPOLINE_32BIT_SIZE;
}
-struct paging_config paging_prepare(void *rmode)
+bool trampoline_pgtable_init(struct boot_params *boot_params)
{
- struct paging_config paging_config = {};
-
- /* Initialize boot_params. Required for cmdline_find_option_bool(). */
- boot_params = rmode;
/*
* Check if LA57 is desired and supported.
@@ -125,26 +121,10 @@ struct paging_config paging_prepare(void *rmode)
*
* That's substitute for boot_cpu_has() in early boot code.
*/
- if (IS_ENABLED(CONFIG_X86_5LEVEL) &&
- !cmdline_find_option_bool("no5lvl") &&
- native_cpuid_eax(0) >= 7 &&
- (native_cpuid_ecx(7) & (1 << (X86_FEATURE_LA57 & 31)))) {
- paging_config.l5_required = 1;
- }
-
- paging_config.trampoline_start = find_trampoline_placement();
-
- trampoline_32bit = (unsigned long *)paging_config.trampoline_start;
-
- /* Preserve trampoline memory */
- memcpy(trampoline_save, trampoline_32bit, TRAMPOLINE_32BIT_SIZE);
-
- /* Clear trampoline memory first */
- memset(trampoline_32bit, 0, TRAMPOLINE_32BIT_SIZE);
-
- /* Copy trampoline code in place */
- memcpy(trampoline_32bit + TRAMPOLINE_32BIT_CODE_OFFSET / sizeof(unsigned long),
- &trampoline_32bit_src, TRAMPOLINE_32BIT_CODE_SIZE);
+ bool l5_required = IS_ENABLED(CONFIG_X86_5LEVEL) &&
+ !cmdline_find_option_bool("no5lvl") &&
+ native_cpuid_eax(0) >= 7 &&
+ (native_cpuid_ecx(7) & (1 << (X86_FEATURE_LA57 & 31)));
/*
* The code below prepares page table in trampoline memory.
@@ -160,10 +140,10 @@ struct paging_config paging_prepare(void *rmode)
* We are not going to use the page table in trampoline memory if we
* are already in the desired paging mode.
*/
- if (paging_config.l5_required == !!(native_read_cr4() & X86_CR4_LA57))
+ if (l5_required == !!(native_read_cr4() & X86_CR4_LA57))
goto out;
- if (paging_config.l5_required) {
+ if (l5_required) {
/*
* For 4- to 5-level paging transition, set up current CR3 as
* the first and the only entry in a new top-level page table.
@@ -185,6 +165,45 @@ struct paging_config paging_prepare(void *rmode)
(void *)src, PAGE_SIZE);
}
+out:
+ return l5_required;
+}
+
+struct paging_config paging_prepare(void *rmode)
+{
+ struct paging_config paging_config = {};
+ bool early_trampoline_alloc = 0;
+
+ /* Initialize boot_params. Required for cmdline_find_option_bool(). */
+ boot_params = rmode;
+
+ /*
+ * We only need to find trampoline placement, if we have
+ * not already done it from libstub.
+ */
+
+ paging_config.trampoline_start = find_trampoline_placement();
+ trampoline_32bit = (unsigned long *)paging_config.trampoline_start;
+ early_trampoline_alloc = 0;
+
+ /*
+ * Preserve trampoline memory.
+ * When trampoline is located in memory
+ * owned by us, i.e. allocated in EFISTUB,
+ * we don't care about previous contents
+ * of this memory so copying can also be skipped.
+ */
+ memcpy(trampoline_save, trampoline_32bit, TRAMPOLINE_32BIT_SIZE);
+
+ /* Clear trampoline memory first */
+ memset(trampoline_32bit, 0, TRAMPOLINE_32BIT_SIZE);
+
+ /* Copy trampoline code in place */
+ memcpy(trampoline_32bit + TRAMPOLINE_32BIT_CODE_OFFSET / sizeof(unsigned long),
+ &trampoline_32bit_src, TRAMPOLINE_32BIT_CODE_SIZE);
+
+ paging_config.l5_required = trampoline_pgtable_init(boot_params);
+
out:
return paging_config;
}