[IA64-SGI] Fix sn_flush_device_kernel & spinlock initialization
Prarit Bhargava [Fri, 23 Dec 2005 18:33:25 +0000 (13:33 -0500)]
This patch separates the sn_flush_device_list struct into kernel and
common (both kernel and PROM accessible) structures.  As it was, if the
size of a spinlock_t changed (due to additional CONFIG options, etc.) the
sal call which populated the sn_flush_device_list structs would erroneously
write data (and cause memory corruption and/or a panic).

This patch does the following:

1.  Removes sn_flush_device_list and adds sn_flush_device_common and
sn_flush_device_kernel.

2.  Adds a new SAL call to populate a sn_flush_device_common struct per
device, not per widget as previously done.

3.  Correctly initializes each device's sn_flush_device_kernel spinlock_t
struct (before it was only doing each widget's first device).

Signed-off-by: Prarit Bhargava <prarit@sgi.com>
Signed-off-by: Tony Luck <tony.luck@intel.com>

arch/ia64/sn/include/xtalk/hubdev.h
arch/ia64/sn/kernel/io_init.c
arch/ia64/sn/pci/pcibr/pcibr_dma.c
arch/ia64/sn/pci/pcibr/pcibr_provider.c
include/asm-ia64/sn/sn_sal.h

index 71c2b27..4d417c3 100644 (file)
 #define IIO_NUM_ITTES   7
 #define HUB_NUM_BIG_WINDOW      (IIO_NUM_ITTES - 1)
 
-struct sn_flush_device_list {
+/* This struct is shared between the PROM and the kernel.
+ * Changes to this struct will require corresponding changes to the kernel.
+ */
+struct sn_flush_device_common {
        int sfdl_bus;
        int sfdl_slot;
        int sfdl_pin;
-       struct bar_list {
+       struct common_bar_list {
                unsigned long start;
                unsigned long end;
        } sfdl_bar_list[6];
@@ -40,14 +43,19 @@ struct sn_flush_device_list {
        uint32_t sfdl_persistent_busnum;
        uint32_t sfdl_persistent_segment;
        struct pcibus_info *sfdl_pcibus_info;
+};
+
+/* This struct is kernel only and is not used by the PROM */
+struct sn_flush_device_kernel {
        spinlock_t sfdl_flush_lock;
+       struct sn_flush_device_common *common;
 };
 
 /*
- * **widget_p - Used as an array[wid_num][device] of sn_flush_device_list.
+ * **widget_p - Used as an array[wid_num][device] of sn_flush_device_kernel.
  */
 struct sn_flush_nasid_entry  {
-       struct sn_flush_device_list **widget_p; /* Used as a array of wid_num */
+       struct sn_flush_device_kernel **widget_p; // Used as an array of wid_num
        uint64_t iio_itte[8];
 };
 
index 318087e..258d9d7 100644 (file)
@@ -76,11 +76,12 @@ static struct sn_pcibus_provider sn_pci_default_provider = {
 };
 
 /*
- * Retrieve the DMA Flush List given nasid.  This list is needed 
- * to implement the WAR - Flush DMA data on PIO Reads.
+ * Retrieve the DMA Flush List given nasid, widget, and device.
+ * This list is needed to implement the WAR - Flush DMA data on PIO Reads.
  */
-static inline uint64_t
-sal_get_widget_dmaflush_list(u64 nasid, u64 widget_num, u64 address)
+static inline u64
+sal_get_device_dmaflush_list(u64 nasid, u64 widget_num, u64 device_num,
+                            u64 address)
 {
 
        struct ia64_sal_retval ret_stuff;
@@ -88,17 +89,17 @@ sal_get_widget_dmaflush_list(u64 nasid, u64 widget_num, u64 address)
        ret_stuff.v0 = 0;
 
        SAL_CALL_NOLOCK(ret_stuff,
-                       (u64) SN_SAL_IOIF_GET_WIDGET_DMAFLUSH_LIST,
-                       (u64) nasid, (u64) widget_num, (u64) address, 0, 0, 0,
-                       0);
-       return ret_stuff.v0;
+                       (u64) SN_SAL_IOIF_GET_DEVICE_DMAFLUSH_LIST,
+                       (u64) nasid, (u64) widget_num,
+                       (u64) device_num, (u64) address, 0, 0, 0);
+       return ret_stuff.status;
 
 }
 
 /*
  * Retrieve the hub device info structure for the given nasid.
  */
-static inline uint64_t sal_get_hubdev_info(u64 handle, u64 address)
+static inline u64 sal_get_hubdev_info(u64 handle, u64 address)
 {
 
        struct ia64_sal_retval ret_stuff;
@@ -114,7 +115,7 @@ static inline uint64_t sal_get_hubdev_info(u64 handle, u64 address)
 /*
  * Retrieve the pci bus information given the bus number.
  */
-static inline uint64_t sal_get_pcibus_info(u64 segment, u64 busnum, u64 address)
+static inline u64 sal_get_pcibus_info(u64 segment, u64 busnum, u64 address)
 {
 
        struct ia64_sal_retval ret_stuff;
@@ -130,7 +131,7 @@ static inline uint64_t sal_get_pcibus_info(u64 segment, u64 busnum, u64 address)
 /*
  * Retrieve the pci device information given the bus and device|function number.
  */
-static inline uint64_t
+static inline u64
 sal_get_pcidev_info(u64 segment, u64 bus_number, u64 devfn, u64 pci_dev, 
                        u64 sn_irq_info)
 {
@@ -170,12 +171,12 @@ sn_pcidev_info_get(struct pci_dev *dev)
  */
 static void sn_fixup_ionodes(void)
 {
-
-       struct sn_flush_device_list *sn_flush_device_list;
+       struct sn_flush_device_kernel *sn_flush_device_kernel;
+       struct sn_flush_device_kernel *dev_entry;
        struct hubdev_info *hubdev;
-       uint64_t status;
-       uint64_t nasid;
-       int i, widget;
+       u64 status;
+       u64 nasid;
+       int i, widget, device;
 
        /*
         * Get SGI Specific HUB chipset information.
@@ -186,7 +187,7 @@ static void sn_fixup_ionodes(void)
                nasid = cnodeid_to_nasid(i);
                hubdev->max_segment_number = 0xffffffff;
                hubdev->max_pcibus_number = 0xff;
-               status = sal_get_hubdev_info(nasid, (uint64_t) __pa(hubdev));
+               status = sal_get_hubdev_info(nasid, (u64) __pa(hubdev));
                if (status)
                        continue;
 
@@ -213,38 +214,49 @@ static void sn_fixup_ionodes(void)
 
                hubdev->hdi_flush_nasid_list.widget_p =
                    kmalloc((HUB_WIDGET_ID_MAX + 1) *
-                           sizeof(struct sn_flush_device_list *), GFP_KERNEL);
-
+                           sizeof(struct sn_flush_device_kernel *),
+                           GFP_KERNEL);
                memset(hubdev->hdi_flush_nasid_list.widget_p, 0x0,
                       (HUB_WIDGET_ID_MAX + 1) *
-                      sizeof(struct sn_flush_device_list *));
+                      sizeof(struct sn_flush_device_kernel *));
 
                for (widget = 0; widget <= HUB_WIDGET_ID_MAX; widget++) {
-                       sn_flush_device_list = kmalloc(DEV_PER_WIDGET *
-                                                      sizeof(struct
-                                                             sn_flush_device_list),
-                                                      GFP_KERNEL);
-                       memset(sn_flush_device_list, 0x0,
+                       sn_flush_device_kernel = kmalloc(DEV_PER_WIDGET *
+                                                        sizeof(struct
+                                                       sn_flush_device_kernel),
+                                                       GFP_KERNEL);
+                       if (!sn_flush_device_kernel)
+                               BUG();
+                       memset(sn_flush_device_kernel, 0x0,
                               DEV_PER_WIDGET *
-                              sizeof(struct sn_flush_device_list));
-
-                       status =
-                           sal_get_widget_dmaflush_list(nasid, widget,
-                                                        (uint64_t)
-                                                        __pa
-                                                        (sn_flush_device_list));
-                       if (status) {
-                               kfree(sn_flush_device_list);
-                               continue;
+                              sizeof(struct sn_flush_device_kernel));
+
+                       dev_entry = sn_flush_device_kernel;
+                       for (device = 0; device < DEV_PER_WIDGET;
+                            device++,dev_entry++) {
+                               dev_entry->common = kmalloc(sizeof(struct
+                                                       sn_flush_device_common),
+                                                           GFP_KERNEL);
+                               if (!dev_entry->common)
+                                       BUG();
+                               memset(dev_entry->common, 0x0, sizeof(struct
+                                                      sn_flush_device_common));
+
+                               status = sal_get_device_dmaflush_list(nasid,
+                                                                       widget,
+                                                                       device,
+                                                     (u64)(dev_entry->common));
+                               if (status)
+                                       BUG();
+
+                               spin_lock_init(&dev_entry->sfdl_flush_lock);
                        }
 
-                       spin_lock_init(&sn_flush_device_list->sfdl_flush_lock);
-                       hubdev->hdi_flush_nasid_list.widget_p[widget] =
-                           sn_flush_device_list;
-               }
-
+                       if (sn_flush_device_kernel)
+                               hubdev->hdi_flush_nasid_list.widget_p[widget] =
+                                                      sn_flush_device_kernel;
+               }
        }
-
 }
 
 /*
index 3409347..e68332d 100644 (file)
@@ -218,7 +218,9 @@ void sn_dma_flush(uint64_t addr)
        uint64_t flags;
        uint64_t itte;
        struct hubdev_info *hubinfo;
-       volatile struct sn_flush_device_list *p;
+       volatile struct sn_flush_device_kernel *p;
+       volatile struct sn_flush_device_common *common;
+
        struct sn_flush_nasid_entry *flush_nasid_list;
 
        if (!sn_ioif_inited)
@@ -268,17 +270,17 @@ void sn_dma_flush(uint64_t addr)
        p = &flush_nasid_list->widget_p[wid_num][0];
 
        /* find a matching BAR */
-       for (i = 0; i < DEV_PER_WIDGET; i++) {
+       for (i = 0; i < DEV_PER_WIDGET; i++,p++) {
+               common = p->common;
                for (j = 0; j < PCI_ROM_RESOURCE; j++) {
-                       if (p->sfdl_bar_list[j].start == 0)
+                       if (common->sfdl_bar_list[j].start == 0)
                                break;
-                       if (addr >= p->sfdl_bar_list[j].start
-                           && addr <= p->sfdl_bar_list[j].end)
+                       if (addr >= common->sfdl_bar_list[j].start
+                           && addr <= common->sfdl_bar_list[j].end)
                                break;
                }
-               if (j < PCI_ROM_RESOURCE && p->sfdl_bar_list[j].start != 0)
+               if (j < PCI_ROM_RESOURCE && common->sfdl_bar_list[j].start != 0)
                        break;
-               p++;
        }
 
        /* if no matching BAR, return without doing anything. */
@@ -304,24 +306,24 @@ void sn_dma_flush(uint64_t addr)
                if ((1 << XWIDGET_PART_REV_NUM_REV(revnum)) & PV907516) {
                        return;
                } else {
-                       pcireg_wrb_flush_get(p->sfdl_pcibus_info,
-                                            (p->sfdl_slot - 1));
+                       pcireg_wrb_flush_get(common->sfdl_pcibus_info,
+                                            (common->sfdl_slot - 1));
                }
        } else {
-               spin_lock_irqsave(&((struct sn_flush_device_list *)p)->
-                                 sfdl_flush_lock, flags);
-
-               *p->sfdl_flush_addr = 0;
+               spin_lock_irqsave((spinlock_t *)&p->sfdl_flush_lock,
+                                 flags);
+               *common->sfdl_flush_addr = 0;
 
                /* force an interrupt. */
-               *(volatile uint32_t *)(p->sfdl_force_int_addr) = 1;
+               *(volatile uint32_t *)(common->sfdl_force_int_addr) = 1;
 
                /* wait for the interrupt to come back. */
-               while (*(p->sfdl_flush_addr) != 0x10f)
+               while (*(common->sfdl_flush_addr) != 0x10f)
                        cpu_relax();
 
                /* okay, everything is synched up. */
-               spin_unlock_irqrestore((spinlock_t *)&p->sfdl_flush_lock, flags);
+               spin_unlock_irqrestore((spinlock_t *)&p->sfdl_flush_lock,
+                                      flags);
        }
        return;
 }
index 1f500c8..e328e94 100644 (file)
@@ -92,7 +92,8 @@ pcibr_bus_fixup(struct pcibus_bussoft *prom_bussoft, struct pci_controller *cont
        cnodeid_t near_cnode;
        struct hubdev_info *hubdev_info;
        struct pcibus_info *soft;
-       struct sn_flush_device_list *sn_flush_device_list;
+       struct sn_flush_device_kernel *sn_flush_device_kernel;
+       struct sn_flush_device_common *common;
 
        if (! IS_PCI_BRIDGE_ASIC(prom_bussoft->bs_asic_type)) {
                return NULL;
@@ -137,20 +138,19 @@ pcibr_bus_fixup(struct pcibus_bussoft *prom_bussoft, struct pci_controller *cont
        hubdev_info = (struct hubdev_info *)(NODEPDA(cnode)->pdinfo);
 
        if (hubdev_info->hdi_flush_nasid_list.widget_p) {
-               sn_flush_device_list = hubdev_info->hdi_flush_nasid_list.
+               sn_flush_device_kernel = hubdev_info->hdi_flush_nasid_list.
                    widget_p[(int)soft->pbi_buscommon.bs_xid];
-               if (sn_flush_device_list) {
+               if (sn_flush_device_kernel) {
                        for (j = 0; j < DEV_PER_WIDGET;
-                            j++, sn_flush_device_list++) {
-                               if (sn_flush_device_list->sfdl_slot == -1)
+                            j++, sn_flush_device_kernel++) {
+                               common = sn_flush_device_kernel->common;
+                               if (common->sfdl_slot == -1)
                                        continue;
-                               if ((sn_flush_device_list->
-                                    sfdl_persistent_segment ==
+                               if ((common->sfdl_persistent_segment ==
                                     soft->pbi_buscommon.bs_persist_segment) &&
-                                    (sn_flush_device_list->
-                                    sfdl_persistent_busnum ==
+                                    (common->sfdl_persistent_busnum ==
                                     soft->pbi_buscommon.bs_persist_busnum))
-                                       sn_flush_device_list->sfdl_pcibus_info =
+                                       common->sfdl_pcibus_info =
                                            soft;
                        }
                }
index 4363ed3..8b9e10e 100644 (file)
@@ -75,7 +75,8 @@
 #define  SN_SAL_IOIF_GET_HUBDEV_INFO              0x02000055
 #define  SN_SAL_IOIF_GET_PCIBUS_INFO              0x02000056
 #define  SN_SAL_IOIF_GET_PCIDEV_INFO              0x02000057
-#define  SN_SAL_IOIF_GET_WIDGET_DMAFLUSH_LIST     0x02000058
+#define  SN_SAL_IOIF_GET_WIDGET_DMAFLUSH_LIST     0x02000058   // deprecated
+#define  SN_SAL_IOIF_GET_DEVICE_DMAFLUSH_LIST     0x0200005a
 
 #define SN_SAL_HUB_ERROR_INTERRUPT                0x02000060
 #define SN_SAL_BTE_RECOVER                        0x02000061