x86/sev: Rename snp_init() in boot/compressed/sev.c

The snp_init() function in boot/compressed/sev.c is local to that file, is
not called from outside of the file and is independent of the snp_init()
function in kernel/sev.c. Change the name to better differentiate when
each function is used.

Move the renamed snp_init() and related functions up in the file to avoid
having to add a forward declaration and make the function static.

No functional change.

Signed-off-by: Tom Lendacky <thomas.lendacky@amd.com>
Signed-off-by: Borislav Petkov (AMD) <bp@alien8.de>
Link: https://lore.kernel.org/r/afda29585c2724b9698003f24cefa77eb35f4ffb.1713974291.git.thomas.lendacky@amd.com

diff --git a/arch/x86/boot/compressed/sev.c b/arch/x86/boot/compressed/sev.c
index ec71846d28c9ed1230fc910954974aca73e51fcf..5ad0ff4664f14dad019925ef28b0532f770cdf55 100644 (file)
--- a/arch/x86/boot/compressed/sev.c
+++ b/arch/x86/boot/compressed/sev.c
@@ -413,6 +413,85 @@ void snp_check_features(void)
        }
 }
 
+/* Search for Confidential Computing blob in the EFI config table. */
+static struct cc_blob_sev_info *find_cc_blob_efi(struct boot_params *bp)
+{
+       unsigned long cfg_table_pa;
+       unsigned int cfg_table_len;
+       int ret;
+
+       ret = efi_get_conf_table(bp, &cfg_table_pa, &cfg_table_len);
+       if (ret)
+               return NULL;
+
+       return (struct cc_blob_sev_info *)efi_find_vendor_table(bp, cfg_table_pa,
+                                                               cfg_table_len,
+                                                               EFI_CC_BLOB_GUID);
+}
+
+/*
+ * Initial set up of SNP relies on information provided by the
+ * Confidential Computing blob, which can be passed to the boot kernel
+ * by firmware/bootloader in the following ways:
+ *
+ * - via an entry in the EFI config table
+ * - via a setup_data structure, as defined by the Linux Boot Protocol
+ *
+ * Scan for the blob in that order.
+ */
+static struct cc_blob_sev_info *find_cc_blob(struct boot_params *bp)
+{
+       struct cc_blob_sev_info *cc_info;
+
+       cc_info = find_cc_blob_efi(bp);
+       if (cc_info)
+               goto found_cc_info;
+
+       cc_info = find_cc_blob_setup_data(bp);
+       if (!cc_info)
+               return NULL;
+
+found_cc_info:
+       if (cc_info->magic != CC_BLOB_SEV_HDR_MAGIC)
+               sev_es_terminate(SEV_TERM_SET_GEN, GHCB_SNP_UNSUPPORTED);
+
+       return cc_info;
+}
+
+/*
+ * Indicate SNP based on presence of SNP-specific CC blob. Subsequent checks
+ * will verify the SNP CPUID/MSR bits.
+ */
+static bool early_snp_init(struct boot_params *bp)
+{
+       struct cc_blob_sev_info *cc_info;
+
+       if (!bp)
+               return false;
+
+       cc_info = find_cc_blob(bp);
+       if (!cc_info)
+               return false;
+
+       /*
+        * If a SNP-specific Confidential Computing blob is present, then
+        * firmware/bootloader have indicated SNP support. Verifying this
+        * involves CPUID checks which will be more reliable if the SNP
+        * CPUID table is used. See comments over snp_setup_cpuid_table() for
+        * more details.
+        */
+       setup_cpuid_table(cc_info);
+
+       /*
+        * Pass run-time kernel a pointer to CC info via boot_params so EFI
+        * config table doesn't need to be searched again during early startup
+        * phase.
+        */
+       bp->cc_blob_address = (u32)(unsigned long)cc_info;
+
+       return true;
+}
+
 /*
  * sev_check_cpu_support - Check for SEV support in the CPU capabilities
  *
@@ -463,7 +542,7 @@ void sev_enable(struct boot_params *bp)
                bp->cc_blob_address = 0;
 
        /*
-        * Do an initial SEV capability check before snp_init() which
+        * Do an initial SEV capability check before early_snp_init() which
         * loads the CPUID page and the same checks afterwards are done
         * without the hypervisor and are trustworthy.
         *
@@ -478,7 +557,7 @@ void sev_enable(struct boot_params *bp)
         * Setup/preliminary detection of SNP. This will be sanity-checked
         * against CPUID/MSR values later.
         */
-       snp = snp_init(bp);
+       snp = early_snp_init(bp);
 
        /* Now repeat the checks with the SNP CPUID table. */
 
@@ -535,85 +614,6 @@ u64 sev_get_status(void)
        return m.q;
 }
 
-/* Search for Confidential Computing blob in the EFI config table. */
-static struct cc_blob_sev_info *find_cc_blob_efi(struct boot_params *bp)
-{
-       unsigned long cfg_table_pa;
-       unsigned int cfg_table_len;
-       int ret;
-
-       ret = efi_get_conf_table(bp, &cfg_table_pa, &cfg_table_len);
-       if (ret)
-               return NULL;
-
-       return (struct cc_blob_sev_info *)efi_find_vendor_table(bp, cfg_table_pa,
-                                                               cfg_table_len,
-                                                               EFI_CC_BLOB_GUID);
-}
-
-/*
- * Initial set up of SNP relies on information provided by the
- * Confidential Computing blob, which can be passed to the boot kernel
- * by firmware/bootloader in the following ways:
- *
- * - via an entry in the EFI config table
- * - via a setup_data structure, as defined by the Linux Boot Protocol
- *
- * Scan for the blob in that order.
- */
-static struct cc_blob_sev_info *find_cc_blob(struct boot_params *bp)
-{
-       struct cc_blob_sev_info *cc_info;
-
-       cc_info = find_cc_blob_efi(bp);
-       if (cc_info)
-               goto found_cc_info;
-
-       cc_info = find_cc_blob_setup_data(bp);
-       if (!cc_info)
-               return NULL;
-
-found_cc_info:
-       if (cc_info->magic != CC_BLOB_SEV_HDR_MAGIC)
-               sev_es_terminate(SEV_TERM_SET_GEN, GHCB_SNP_UNSUPPORTED);
-
-       return cc_info;
-}
-
-/*
- * Indicate SNP based on presence of SNP-specific CC blob. Subsequent checks
- * will verify the SNP CPUID/MSR bits.
- */
-bool snp_init(struct boot_params *bp)
-{
-       struct cc_blob_sev_info *cc_info;
-
-       if (!bp)
-               return false;
-
-       cc_info = find_cc_blob(bp);
-       if (!cc_info)
-               return false;
-
-       /*
-        * If a SNP-specific Confidential Computing blob is present, then
-        * firmware/bootloader have indicated SNP support. Verifying this
-        * involves CPUID checks which will be more reliable if the SNP
-        * CPUID table is used. See comments over snp_setup_cpuid_table() for
-        * more details.
-        */
-       setup_cpuid_table(cc_info);
-
-       /*
-        * Pass run-time kernel a pointer to CC info via boot_params so EFI
-        * config table doesn't need to be searched again during early startup
-        * phase.
-        */
-       bp->cc_blob_address = (u32)(unsigned long)cc_info;
-
-       return true;
-}
-
 void sev_prep_identity_maps(unsigned long top_level_pgt)
 {
        /*