NLM: Fix reclaim races

[linux-2.6/suspend2-2.6.18.git] / drivers / edac / edac_mc.h

/*
 * MC kernel module
 * (C) 2003 Linux Networx (http://lnxi.com)
 * This file may be distributed under the terms of the
 * GNU General Public License.
 *
 * Written by Thayne Harbaugh
 * Based on work by Dan Hollis <goemon at anime dot net> and others.
 *      http://www.anime.net/~goemon/linux-ecc/
 *
 * NMI handling support added by
 *     Dave Peterson <dsp@llnl.gov> <dave_peterson@pobox.com>
 *
 * $Id: edac_mc.h,v 1.4.2.10 2005/10/05 00:43:44 dsp_llnl Exp $
 *
 */

#ifndef _EDAC_MC_H_
#define _EDAC_MC_H_

#include <linux/config.h>
#include <linux/kernel.h>
#include <linux/types.h>
#include <linux/module.h>
#include <linux/spinlock.h>
#include <linux/smp.h>
#include <linux/pci.h>
#include <linux/time.h>
#include <linux/nmi.h>
#include <linux/rcupdate.h>
#include <linux/completion.h>
#include <linux/kobject.h>

#define EDAC_MC_LABEL_LEN       31
#define MC_PROC_NAME_MAX_LEN 7

#if PAGE_SHIFT < 20
#define PAGES_TO_MiB( pages )   ( ( pages ) >> ( 20 - PAGE_SHIFT ) )
#else                           /* PAGE_SHIFT > 20 */
#define PAGES_TO_MiB( pages )   ( ( pages ) << ( PAGE_SHIFT - 20 ) )
#endif

#define edac_printk(level, prefix, fmt, arg...) \
        printk(level "EDAC " prefix ": " fmt, ##arg)

#define edac_mc_printk(mci, level, fmt, arg...) \
        printk(level "EDAC MC%d: " fmt, mci->mc_idx, ##arg)

#define edac_mc_chipset_printk(mci, level, prefix, fmt, arg...) \
        printk(level "EDAC " prefix " MC%d: " fmt, mci->mc_idx, ##arg)

/* prefixes for edac_printk() and edac_mc_printk() */
#define EDAC_MC "MC"
#define EDAC_PCI "PCI"
#define EDAC_DEBUG "DEBUG"

#ifdef CONFIG_EDAC_DEBUG
extern int edac_debug_level;

#define edac_debug_printk(level, fmt, arg...)                            \
        do {                                                             \
                if (level <= edac_debug_level)                           \
                        edac_printk(KERN_DEBUG, EDAC_DEBUG, fmt, ##arg); \
        } while(0)

#define debugf0( ... ) edac_debug_printk(0, __VA_ARGS__ )
#define debugf1( ... ) edac_debug_printk(1, __VA_ARGS__ )
#define debugf2( ... ) edac_debug_printk(2, __VA_ARGS__ )
#define debugf3( ... ) edac_debug_printk(3, __VA_ARGS__ )
#define debugf4( ... ) edac_debug_printk(4, __VA_ARGS__ )

#else  /* !CONFIG_EDAC_DEBUG */

#define debugf0( ... )
#define debugf1( ... )
#define debugf2( ... )
#define debugf3( ... )
#define debugf4( ... )

#endif  /* !CONFIG_EDAC_DEBUG */

#define edac_xstr(s) edac_str(s)
#define edac_str(s) #s
#define EDAC_MOD_STR edac_xstr(KBUILD_BASENAME)

#define BIT(x) (1 << (x))

#define PCI_VEND_DEV(vend, dev) PCI_VENDOR_ID_ ## vend, \
        PCI_DEVICE_ID_ ## vend ## _ ## dev

/* memory devices */
enum dev_type {
        DEV_UNKNOWN = 0,
        DEV_X1,
        DEV_X2,
        DEV_X4,
        DEV_X8,
        DEV_X16,
        DEV_X32,                /* Do these parts exist? */
        DEV_X64                 /* Do these parts exist? */
};

#define DEV_FLAG_UNKNOWN        BIT(DEV_UNKNOWN)
#define DEV_FLAG_X1             BIT(DEV_X1)
#define DEV_FLAG_X2             BIT(DEV_X2)
#define DEV_FLAG_X4             BIT(DEV_X4)
#define DEV_FLAG_X8             BIT(DEV_X8)
#define DEV_FLAG_X16            BIT(DEV_X16)
#define DEV_FLAG_X32            BIT(DEV_X32)
#define DEV_FLAG_X64            BIT(DEV_X64)

/* memory types */
enum mem_type {
        MEM_EMPTY = 0,          /* Empty csrow */
        MEM_RESERVED,           /* Reserved csrow type */
        MEM_UNKNOWN,            /* Unknown csrow type */
        MEM_FPM,                /* Fast page mode */
        MEM_EDO,                /* Extended data out */
        MEM_BEDO,               /* Burst Extended data out */
        MEM_SDR,                /* Single data rate SDRAM */
        MEM_RDR,                /* Registered single data rate SDRAM */
        MEM_DDR,                /* Double data rate SDRAM */
        MEM_RDDR,               /* Registered Double data rate SDRAM */
        MEM_RMBS                /* Rambus DRAM */
};

#define MEM_FLAG_EMPTY          BIT(MEM_EMPTY)
#define MEM_FLAG_RESERVED       BIT(MEM_RESERVED)
#define MEM_FLAG_UNKNOWN        BIT(MEM_UNKNOWN)
#define MEM_FLAG_FPM            BIT(MEM_FPM)
#define MEM_FLAG_EDO            BIT(MEM_EDO)
#define MEM_FLAG_BEDO           BIT(MEM_BEDO)
#define MEM_FLAG_SDR            BIT(MEM_SDR)
#define MEM_FLAG_RDR            BIT(MEM_RDR)
#define MEM_FLAG_DDR            BIT(MEM_DDR)
#define MEM_FLAG_RDDR           BIT(MEM_RDDR)
#define MEM_FLAG_RMBS           BIT(MEM_RMBS)

/* chipset Error Detection and Correction capabilities and mode */
enum edac_type {
        EDAC_UNKNOWN = 0,       /* Unknown if ECC is available */
        EDAC_NONE,              /* Doesnt support ECC */
        EDAC_RESERVED,          /* Reserved ECC type */
        EDAC_PARITY,            /* Detects parity errors */
        EDAC_EC,                /* Error Checking - no correction */
        EDAC_SECDED,            /* Single bit error correction, Double detection */
        EDAC_S2ECD2ED,          /* Chipkill x2 devices - do these exist? */
        EDAC_S4ECD4ED,          /* Chipkill x4 devices */
        EDAC_S8ECD8ED,          /* Chipkill x8 devices */
        EDAC_S16ECD16ED,        /* Chipkill x16 devices */
};

#define EDAC_FLAG_UNKNOWN       BIT(EDAC_UNKNOWN)
#define EDAC_FLAG_NONE          BIT(EDAC_NONE)
#define EDAC_FLAG_PARITY        BIT(EDAC_PARITY)
#define EDAC_FLAG_EC            BIT(EDAC_EC)
#define EDAC_FLAG_SECDED        BIT(EDAC_SECDED)
#define EDAC_FLAG_S2ECD2ED      BIT(EDAC_S2ECD2ED)
#define EDAC_FLAG_S4ECD4ED      BIT(EDAC_S4ECD4ED)
#define EDAC_FLAG_S8ECD8ED      BIT(EDAC_S8ECD8ED)
#define EDAC_FLAG_S16ECD16ED    BIT(EDAC_S16ECD16ED)

/* scrubbing capabilities */
enum scrub_type {
        SCRUB_UNKNOWN = 0,      /* Unknown if scrubber is available */
        SCRUB_NONE,             /* No scrubber */
        SCRUB_SW_PROG,          /* SW progressive (sequential) scrubbing */
        SCRUB_SW_SRC,           /* Software scrub only errors */
        SCRUB_SW_PROG_SRC,      /* Progressive software scrub from an error */
        SCRUB_SW_TUNABLE,       /* Software scrub frequency is tunable */
        SCRUB_HW_PROG,          /* HW progressive (sequential) scrubbing */
        SCRUB_HW_SRC,           /* Hardware scrub only errors */
        SCRUB_HW_PROG_SRC,      /* Progressive hardware scrub from an error */
        SCRUB_HW_TUNABLE        /* Hardware scrub frequency is tunable */
};

#define SCRUB_FLAG_SW_PROG      BIT(SCRUB_SW_PROG)
#define SCRUB_FLAG_SW_SRC       BIT(SCRUB_SW_SRC_CORR)
#define SCRUB_FLAG_SW_PROG_SRC  BIT(SCRUB_SW_PROG_SRC_CORR)
#define SCRUB_FLAG_SW_TUN       BIT(SCRUB_SW_SCRUB_TUNABLE)
#define SCRUB_FLAG_HW_PROG      BIT(SCRUB_HW_PROG)
#define SCRUB_FLAG_HW_SRC       BIT(SCRUB_HW_SRC_CORR)
#define SCRUB_FLAG_HW_PROG_SRC  BIT(SCRUB_HW_PROG_SRC_CORR)
#define SCRUB_FLAG_HW_TUN       BIT(SCRUB_HW_TUNABLE)

/* FIXME - should have notify capabilities: NMI, LOG, PROC, etc */

/*
 * There are several things to be aware of that aren't at all obvious:
 *
 *
 * SOCKETS, SOCKET SETS, BANKS, ROWS, CHIP-SELECT ROWS, CHANNELS, etc..
 *
 * These are some of the many terms that are thrown about that don't always
 * mean what people think they mean (Inconceivable!).  In the interest of
 * creating a common ground for discussion, terms and their definitions
 * will be established.
 *
 * Memory devices:      The individual chip on a memory stick.  These devices
 *                      commonly output 4 and 8 bits each.  Grouping several
 *                      of these in parallel provides 64 bits which is common
 *                      for a memory stick.
 *
 * Memory Stick:        A printed circuit board that agregates multiple
 *                      memory devices in parallel.  This is the atomic
 *                      memory component that is purchaseable by Joe consumer
 *                      and loaded into a memory socket.
 *
 * Socket:              A physical connector on the motherboard that accepts
 *                      a single memory stick.
 *
 * Channel:             Set of memory devices on a memory stick that must be
 *                      grouped in parallel with one or more additional
 *                      channels from other memory sticks.  This parallel
 *                      grouping of the output from multiple channels are
 *                      necessary for the smallest granularity of memory access.
 *                      Some memory controllers are capable of single channel -
 *                      which means that memory sticks can be loaded
 *                      individually.  Other memory controllers are only
 *                      capable of dual channel - which means that memory
 *                      sticks must be loaded as pairs (see "socket set").
 *
 * Chip-select row:     All of the memory devices that are selected together.
 *                      for a single, minimum grain of memory access.
 *                      This selects all of the parallel memory devices across
 *                      all of the parallel channels.  Common chip-select rows
 *                      for single channel are 64 bits, for dual channel 128
 *                      bits.
 *
 * Single-Ranked stick: A Single-ranked stick has 1 chip-select row of memmory.
 *                      Motherboards commonly drive two chip-select pins to
 *                      a memory stick. A single-ranked stick, will occupy
 *                      only one of those rows. The other will be unused.
 *
 * Double-Ranked stick: A double-ranked stick has two chip-select rows which
 *                      access different sets of memory devices.  The two
 *                      rows cannot be accessed concurrently.
 *
 * Double-sided stick:  DEPRECATED TERM, see Double-Ranked stick.
 *                      A double-sided stick has two chip-select rows which
 *                      access different sets of memory devices.  The two
 *                      rows cannot be accessed concurrently.  "Double-sided"
 *                      is irrespective of the memory devices being mounted
 *                      on both sides of the memory stick.
 *
 * Socket set:          All of the memory sticks that are required for for
 *                      a single memory access or all of the memory sticks
 *                      spanned by a chip-select row.  A single socket set
 *                      has two chip-select rows and if double-sided sticks
 *                      are used these will occupy those chip-select rows.
 *
 * Bank:                This term is avoided because it is unclear when
 *                      needing to distinguish between chip-select rows and
 *                      socket sets.
 *
 * Controller pages:
 *
 * Physical pages:
 *
 * Virtual pages:
 *
 *
 * STRUCTURE ORGANIZATION AND CHOICES
 *
 *
 *
 * PS - I enjoyed writing all that about as much as you enjoyed reading it.
 */

struct channel_info {
        int chan_idx;           /* channel index */
        u32 ce_count;           /* Correctable Errors for this CHANNEL */
        char label[EDAC_MC_LABEL_LEN + 1];  /* DIMM label on motherboard */
        struct csrow_info *csrow;       /* the parent */
};

struct csrow_info {
        unsigned long first_page;       /* first page number in dimm */
        unsigned long last_page;        /* last page number in dimm */
        unsigned long page_mask;        /* used for interleaving -
                                         * 0UL for non intlv
                                         */
        u32 nr_pages;           /* number of pages in csrow */
        u32 grain;              /* granularity of reported error in bytes */
        int csrow_idx;          /* the chip-select row */
        enum dev_type dtype;    /* memory device type */
        u32 ue_count;           /* Uncorrectable Errors for this csrow */
        u32 ce_count;           /* Correctable Errors for this csrow */
        enum mem_type mtype;    /* memory csrow type */
        enum edac_type edac_mode;       /* EDAC mode for this csrow */
        struct mem_ctl_info *mci;       /* the parent */

        struct kobject kobj;    /* sysfs kobject for this csrow */
        struct completion kobj_complete;

        /* FIXME the number of CHANNELs might need to become dynamic */
        u32 nr_channels;
        struct channel_info *channels;
};

struct mem_ctl_info {
        struct list_head link;  /* for global list of mem_ctl_info structs */
        unsigned long mtype_cap;        /* memory types supported by mc */
        unsigned long edac_ctl_cap;     /* Mem controller EDAC capabilities */
        unsigned long edac_cap; /* configuration capabilities - this is
                                 * closely related to edac_ctl_cap.  The
                                 * difference is that the controller may be
                                 * capable of s4ecd4ed which would be listed
                                 * in edac_ctl_cap, but if channels aren't
                                 * capable of s4ecd4ed then the edac_cap would
                                 * not have that capability.
                                 */
        unsigned long scrub_cap;        /* chipset scrub capabilities */
        enum scrub_type scrub_mode;     /* current scrub mode */

        /* pointer to edac checking routine */
        void (*edac_check) (struct mem_ctl_info * mci);
        /*
         * Remaps memory pages: controller pages to physical pages.
         * For most MC's, this will be NULL.
         */
        /* FIXME - why not send the phys page to begin with? */
        unsigned long (*ctl_page_to_phys) (struct mem_ctl_info * mci,
                                        unsigned long page);
        int mc_idx;
        int nr_csrows;
        struct csrow_info *csrows;
        /*
         * FIXME - what about controllers on other busses? - IDs must be
         * unique.  pdev pointer should be sufficiently unique, but
         * BUS:SLOT.FUNC numbers may not be unique.
         */
        struct pci_dev *pdev;
        const char *mod_name;
        const char *mod_ver;
        const char *ctl_name;
        char proc_name[MC_PROC_NAME_MAX_LEN + 1];
        void *pvt_info;
        u32 ue_noinfo_count;    /* Uncorrectable Errors w/o info */
        u32 ce_noinfo_count;    /* Correctable Errors w/o info */
        u32 ue_count;           /* Total Uncorrectable Errors for this MC */
        u32 ce_count;           /* Total Correctable Errors for this MC */
        unsigned long start_time;       /* mci load start time (in jiffies) */

        /* this stuff is for safe removal of mc devices from global list while
         * NMI handlers may be traversing list
         */
        struct rcu_head rcu;
        struct completion complete;

        /* edac sysfs device control */
        struct kobject edac_mci_kobj;
        struct completion kobj_complete;
};

/* write all or some bits in a byte-register*/
static inline void pci_write_bits8(struct pci_dev *pdev, int offset, u8 value,
                u8 mask)
{
        if (mask != 0xff) {
                u8 buf;

                pci_read_config_byte(pdev, offset, &buf);
                value &= mask;
                buf &= ~mask;
                value |= buf;
        }

        pci_write_config_byte(pdev, offset, value);
}

/* write all or some bits in a word-register*/
static inline void pci_write_bits16(struct pci_dev *pdev, int offset,
                u16 value, u16 mask)
{
        if (mask != 0xffff) {
                u16 buf;

                pci_read_config_word(pdev, offset, &buf);
                value &= mask;
                buf &= ~mask;
                value |= buf;
        }

        pci_write_config_word(pdev, offset, value);
}

/* write all or some bits in a dword-register*/
static inline void pci_write_bits32(struct pci_dev *pdev, int offset,
                u32 value, u32 mask)
{
        if (mask != 0xffff) {
                u32 buf;

                pci_read_config_dword(pdev, offset, &buf);
                value &= mask;
                buf &= ~mask;
                value |= buf;
        }

        pci_write_config_dword(pdev, offset, value);
}

#ifdef CONFIG_EDAC_DEBUG
void edac_mc_dump_channel(struct channel_info *chan);
void edac_mc_dump_mci(struct mem_ctl_info *mci);
void edac_mc_dump_csrow(struct csrow_info *csrow);
#endif  /* CONFIG_EDAC_DEBUG */

extern int edac_mc_add_mc(struct mem_ctl_info *mci);
extern struct mem_ctl_info * edac_mc_del_mc(struct pci_dev *pdev);
extern int edac_mc_find_csrow_by_page(struct mem_ctl_info *mci,
                                        unsigned long page);
extern void edac_mc_scrub_block(unsigned long page, unsigned long offset,
                u32 size);

/*
 * The no info errors are used when error overflows are reported.
 * There are a limited number of error logging registers that can
 * be exausted.  When all registers are exhausted and an additional
 * error occurs then an error overflow register records that an
 * error occured and the type of error, but doesn't have any
 * further information.  The ce/ue versions make for cleaner
 * reporting logic and function interface - reduces conditional
 * statement clutter and extra function arguments.
 */
extern void edac_mc_handle_ce(struct mem_ctl_info *mci,
                unsigned long page_frame_number, unsigned long offset_in_page,
                unsigned long syndrome, int row, int channel,
                const char *msg);
extern void edac_mc_handle_ce_no_info(struct mem_ctl_info *mci,
                const char *msg);
extern void edac_mc_handle_ue(struct mem_ctl_info *mci,
                unsigned long page_frame_number, unsigned long offset_in_page,
                int row, const char *msg);
extern void edac_mc_handle_ue_no_info(struct mem_ctl_info *mci,
                const char *msg);

/*
 * This kmalloc's and initializes all the structures.
 * Can't be used if all structures don't have the same lifetime.
 */
extern struct mem_ctl_info *edac_mc_alloc(unsigned sz_pvt, unsigned nr_csrows,
                unsigned nr_chans);

/* Free an mc previously allocated by edac_mc_alloc() */
extern void edac_mc_free(struct mem_ctl_info *mci);

#endif                          /* _EDAC_MC_H_ */