x86/PCI: MMCONFIG: centralize MCFG structure management

This patch encapsulate pci_mmcfg_config[] updates.  All alloc/free is now
done in pci_mmconfig_add() and free_all_mcfg(), so all updates to
pci_mmcfg_config[] and pci_mmcfg_config_num are in those two functions.

This replaces the previous sequence of extend_mmcfg(), fill_one_mmcfg()
with the single pci_mmconfig_add() interface.  This interface is currently
static but will eventually be used in the host bridge hot-add path.

Reviewed-by: Yinghai Lu <yinghai@kernel.org>
Signed-off-by: Bjorn Helgaas <bjorn.helgaas@hp.com>
Signed-off-by: Jesse Barnes <jbarnes@virtuousgeek.org>

1 files changed, 39 insertions, 46 deletions

diff --git a/arch/x86/pci/mmconfig-shared.c b/arch/x86/pci/mmconfig-shared.c
index 7a7b6ba3abb..62a8ecd9698 100644
--- a/arch/x86/pci/mmconfig-shared.c
+++ b/arch/x86/pci/mmconfig-shared.c
@@ -26,14 +26,24 @@
 /* Indicate if the mmcfg resources have been placed into the resource table. */
 static int __initdata pci_mmcfg_resources_inserted;
 
-static __init int extend_mmcfg(int num)
+static __init void free_all_mmcfg(void)
+{
+        pci_mmcfg_arch_free();
+        pci_mmcfg_config_num = 0;
+        kfree(pci_mmcfg_config);
+        pci_mmcfg_config = NULL;
+}
+
+static __init struct acpi_mcfg_allocation *pci_mmconfig_add(int segment,
+        int start, int end, u64 addr)
 {
         struct acpi_mcfg_allocation *new;
-        int new_num = pci_mmcfg_config_num + num;
+        int new_num = pci_mmcfg_config_num + 1;
+        int i = pci_mmcfg_config_num;
 
         new = kzalloc(sizeof(pci_mmcfg_config[0]) * new_num, GFP_KERNEL);
         if (!new)
-                return -1;
+                return NULL;
 
         if (pci_mmcfg_config) {
                 memcpy(new, pci_mmcfg_config,
@@ -42,18 +52,13 @@ static __init int extend_mmcfg(int num)
         }
         pci_mmcfg_config = new;
 
-        return 0;
-}
-
-static __init void fill_one_mmcfg(u64 addr, int segment, int start, int end)
-{
-        int i = pci_mmcfg_config_num;
-
         pci_mmcfg_config_num++;
         pci_mmcfg_config[i].address = addr;
         pci_mmcfg_config[i].pci_segment = segment;
         pci_mmcfg_config[i].start_bus_number = start;
         pci_mmcfg_config[i].end_bus_number = end;
+
+        return &pci_mmcfg_config[i];
 }
 
 static const char __init *pci_mmcfg_e7520(void)
@@ -65,11 +70,9 @@ static const char __init *pci_mmcfg_e7520(void)
         if (win == 0x0000 || win == 0xf000)
                 return NULL;
 
-        if (extend_mmcfg(1) == -1)
+        if (pci_mmconfig_add(0, 0, 255, win << 16) == NULL)
                 return NULL;
 
-        fill_one_mmcfg(win << 16, 0, 0, 255);
-
         return "Intel Corporation E7520 Memory Controller Hub";
 }
 
@@ -111,11 +114,9 @@ static const char __init *pci_mmcfg_intel_945(void)
         if ((pciexbar & mask) >= 0xf0000000U)
                 return NULL;
 
-        if (extend_mmcfg(1) == -1)
+        if (pci_mmconfig_add(0, 0, (len >> 20) - 1, pciexbar & mask) == NULL)
                 return NULL;
 
-        fill_one_mmcfg(pciexbar & mask, 0, 0, (len >> 20) - 1);
-
         return "Intel Corporation 945G/GZ/P/PL Express Memory Controller Hub";
 }
 
@@ -124,7 +125,7 @@ static const char __init *pci_mmcfg_amd_fam10h(void)
         u32 low, high, address;
         u64 base, msr;
         int i;
-        unsigned segnbits = 0, busnbits;
+        unsigned segnbits = 0, busnbits, end_bus;
 
         if (!(pci_probe & PCI_CHECK_ENABLE_AMD_MMCONF))
                 return NULL;
@@ -158,11 +159,13 @@ static const char __init *pci_mmcfg_amd_fam10h(void)
                 busnbits = 8;
         }
 
-        if (extend_mmcfg(1 << segnbits) == -1)
-                return NULL;
-
+        end_bus = (1 << busnbits) - 1;
         for (i = 0; i < (1 << segnbits); i++)
-                fill_one_mmcfg(base + (1<<28) * i, i, 0, (1 << busnbits) - 1);
+                if (pci_mmconfig_add(i, 0, end_bus,
+                                     base + (1<<28) * i) == NULL) {
+                        free_all_mmcfg();
+                        return NULL;
+                }
 
         return "AMD Family 10h NB";
 }
@@ -210,16 +213,14 @@ static const char __init *pci_mmcfg_nvidia_mcp55(void)
                 if (!(extcfg & extcfg_enable_mask))
                         continue;
 
-                if (extend_mmcfg(1) == -1)
-                        continue;
-
                 size_index = (extcfg & extcfg_size_mask) >> extcfg_size_shift;
                 base = extcfg & extcfg_base_mask[size_index];
                 /* base could > 4G */
                 base <<= extcfg_base_lshift;
                 start = (extcfg & extcfg_start_mask) >> extcfg_start_shift;
                 end = start + extcfg_sizebus[size_index] - 1;
-                fill_one_mmcfg(base, 0, start, end);
+                if (pci_mmconfig_add(0, start, end, base) == NULL)
+                        continue;
                 mcp55_mmconf_found++;
         }
 
@@ -303,8 +304,7 @@ static int __init pci_mmcfg_check_hostbridge(void)
         if (!raw_pci_ops)
                 return 0;
 
-        pci_mmcfg_config_num = 0;
-        pci_mmcfg_config = NULL;
+        free_all_mmcfg();
 
         for (i = 0; i < ARRAY_SIZE(pci_mmcfg_probes); i++) {
                 bus =  pci_mmcfg_probes[i].bus;
@@ -516,10 +516,7 @@ static void __init pci_mmcfg_reject_broken(int early)
 
 reject:
         printk(KERN_INFO "PCI: Not using MMCONFIG.\n");
-        pci_mmcfg_arch_free();
-        kfree(pci_mmcfg_config);
-        pci_mmcfg_config = NULL;
-        pci_mmcfg_config_num = 0;
+        free_all_mmcfg();
 }
 
 static int __initdata known_bridge;
@@ -556,7 +553,7 @@ static int __init pci_parse_mcfg(struct acpi_table_header *header)
         struct acpi_table_mcfg *mcfg;
         struct acpi_mcfg_allocation *cfg_table, *cfg;
         unsigned long i;
-        int entries, config_size;
+        int entries;
 
         if (!header)
                 return -EINVAL;
@@ -564,7 +561,7 @@ static int __init pci_parse_mcfg(struct acpi_table_header *header)
         mcfg = (struct acpi_table_mcfg *)header;
 
         /* how many config structures do we have */
-        pci_mmcfg_config_num = 0;
+        free_all_mmcfg();
         entries = 0;
         i = header->length - sizeof(struct acpi_table_mcfg);
         while (i >= sizeof(struct acpi_mcfg_allocation)) {
@@ -576,25 +573,21 @@ static int __init pci_parse_mcfg(struct acpi_table_header *header)
                 return -ENODEV;
         }
 
-        config_size = entries * sizeof(*pci_mmcfg_config);
-        pci_mmcfg_config = kmalloc(config_size, GFP_KERNEL);
-        if (!pci_mmcfg_config) {
-                printk(KERN_WARNING PREFIX
-                       "No memory for MCFG config tables\n");
-                return -ENOMEM;
-        }
-
-        memcpy(pci_mmcfg_config, &mcfg[1], config_size);
-        pci_mmcfg_config_num = entries;
-
         cfg_table = (struct acpi_mcfg_allocation *) &mcfg[1];
         for (i = 0; i < entries; i++) {
                 cfg = &cfg_table[i];
                 if (acpi_mcfg_check_entry(mcfg, cfg)) {
-                        kfree(pci_mmcfg_config);
-                        pci_mmcfg_config_num = 0;
+                        free_all_mmcfg();
                         return -ENODEV;
                 }
+
+                if (pci_mmconfig_add(cfg->pci_segment, cfg->start_bus_number,
+                                   cfg->end_bus_number, cfg->address) == NULL) {
+                        printk(KERN_WARNING PREFIX
+                               "no memory for MCFG entries\n");
+                        free_all_mmcfg();
+                        return -ENOMEM;
+                }
         }
 
         return 0;