/*
 * (C) 2001 Clemson University and The University of Chicago
 *
 * Changes by Acxiom Corporation to add proc file handler for pvfs2 client
 * parameters, Copyright Acxiom Corporation, 2005.
 *
 * See COPYING in top-level directory.
 */

#include "protocol.h"
#include "orangefs-kernel.h"
#include "orangefs-debugfs.h"
#include "orangefs-sysfs.h"

/* ORANGEFS_VERSION is a ./configure define */
#ifndef ORANGEFS_VERSION
#define ORANGEFS_VERSION "upstream"
#endif

/*
 * global variables declared here
 */

struct orangefs_stats orangefs_stats;

/* the size of the hash tables for ops in progress */
int hash_table_size = 509;

static ulong module_parm_debug_mask;
__u64 orangefs_gossip_debug_mask;
int op_timeout_secs = ORANGEFS_DEFAULT_OP_TIMEOUT_SECS;
int slot_timeout_secs = ORANGEFS_DEFAULT_SLOT_TIMEOUT_SECS;
int orangefs_dcache_timeout_msecs = 50;
int orangefs_getattr_timeout_msecs = 50;

MODULE_LICENSE("GPL");
MODULE_AUTHOR("ORANGEFS Development Team");
MODULE_DESCRIPTION("The Linux Kernel VFS interface to ORANGEFS");
MODULE_PARM_DESC(module_parm_debug_mask, "debugging level (see orangefs-debug.h for values)");
MODULE_PARM_DESC(op_timeout_secs, "Operation timeout in seconds");
MODULE_PARM_DESC(slot_timeout_secs, "Slot timeout in seconds");
MODULE_PARM_DESC(hash_table_size,
                 "size of hash table for operations in progress");

static struct file_system_type orangefs_fs_type = {
        .name = "pvfs2",
        .mount = orangefs_mount,
        .kill_sb = orangefs_kill_sb,
        .owner = THIS_MODULE,
};

module_param(hash_table_size, int, 0);
module_param(module_parm_debug_mask, ulong, 0644);
module_param(op_timeout_secs, int, 0);
module_param(slot_timeout_secs, int, 0);

/*
 * Blocks non-priority requests from being queued for servicing.  This
 * could be used for protecting the request list data structure, but
 * for now it's only being used to stall the op addition to the request
 * list
 */
DEFINE_MUTEX(orangefs_request_mutex);

/* hash table for storing operations waiting for matching downcall */
struct list_head *orangefs_htable_ops_in_progress;
DEFINE_SPINLOCK(orangefs_htable_ops_in_progress_lock);

/* list for queueing upcall operations */
LIST_HEAD(orangefs_request_list);

/* used to protect the above orangefs_request_list */
DEFINE_SPINLOCK(orangefs_request_list_lock);

/* used for incoming request notification */
DECLARE_WAIT_QUEUE_HEAD(orangefs_request_list_waitq);

static int __init orangefs_init(void)
{
        int ret = -1;
        __u32 i = 0;

        if (op_timeout_secs < 0)
                op_timeout_secs = 0;

        if (slot_timeout_secs < 0)
                slot_timeout_secs = 0;

        /* initialize global book keeping data structures */
        ret = op_cache_initialize();
        if (ret < 0)
                goto out;

        ret = orangefs_inode_cache_initialize();
        if (ret < 0)
                goto cleanup_op;

        orangefs_htable_ops_in_progress =
            kcalloc(hash_table_size, sizeof(struct list_head), GFP_KERNEL);
        if (!orangefs_htable_ops_in_progress) {
                ret = -ENOMEM;
                goto cleanup_inode;
        }

        /* initialize a doubly linked at each hash table index */
        for (i = 0; i < hash_table_size; i++)
                INIT_LIST_HEAD(&orangefs_htable_ops_in_progress[i]);

        ret = fsid_key_table_initialize();
        if (ret < 0)
                goto cleanup_progress_table;

        /*
         * Build the contents of /sys/kernel/debug/orangefs/debug-help
         * from the keywords in the kernel keyword/mask array.
         *
         * The keywords in the client keyword/mask array are
         * unknown at boot time.
         *
         * orangefs_prepare_debugfs_help_string will be used again
         * later to rebuild the debug-help-string after the client starts
         * and passes along the needed info. The argument signifies
         * which time orangefs_prepare_debugfs_help_string is being
         * called.
         */
        ret = orangefs_prepare_debugfs_help_string(1);
        if (ret)
                goto cleanup_key_table;

        ret = orangefs_debugfs_init(module_parm_debug_mask);
        if (ret)
                goto debugfs_init_failed;

        ret = orangefs_sysfs_init();
        if (ret)
                goto sysfs_init_failed;

        /* Initialize the orangefsdev subsystem. */
        ret = orangefs_dev_init();
        if (ret < 0) {
                gossip_err("%s: could not initialize device subsystem %d!\n",
                           __func__,
                           ret);
                goto cleanup_device;
        }

        ret = register_filesystem(&orangefs_fs_type);
        if (ret == 0) {
                pr_info("%s: module version %s loaded\n",
                        __func__,
                        ORANGEFS_VERSION);
                ret = 0;
                goto out;
        }

        orangefs_sysfs_exit();

cleanup_device:
        orangefs_dev_cleanup();

sysfs_init_failed:

debugfs_init_failed:
        orangefs_debugfs_cleanup();

cleanup_key_table:
        fsid_key_table_finalize();

cleanup_progress_table:
        kfree(orangefs_htable_ops_in_progress);

cleanup_inode:
        orangefs_inode_cache_finalize();

cleanup_op:
        op_cache_finalize();

out:
        return ret;
}

static void __exit orangefs_exit(void)
{
        int i = 0;
        gossip_debug(GOSSIP_INIT_DEBUG, "orangefs: orangefs_exit called\n");

        unregister_filesystem(&orangefs_fs_type);
        orangefs_debugfs_cleanup();
        orangefs_sysfs_exit();
        fsid_key_table_finalize();
        orangefs_dev_cleanup();
        BUG_ON(!list_empty(&orangefs_request_list));
        for (i = 0; i < hash_table_size; i++)
                BUG_ON(!list_empty(&orangefs_htable_ops_in_progress[i]));

        orangefs_inode_cache_finalize();
        op_cache_finalize();

        kfree(orangefs_htable_ops_in_progress);

        pr_info("orangefs: module version %s unloaded\n", ORANGEFS_VERSION);
}

/*
 * What we do in this function is to walk the list of operations
 * that are in progress in the hash table and mark them as purged as well.
 */
void purge_inprogress_ops(void)
{
        int i;

        for (i = 0; i < hash_table_size; i++) {
                struct orangefs_kernel_op_s *op;
                struct orangefs_kernel_op_s *next;

                spin_lock(&orangefs_htable_ops_in_progress_lock);
                list_for_each_entry_safe(op,
                                         next,
                                         &orangefs_htable_ops_in_progress[i],
                                         list) {
                        set_op_state_purged(op);
                        gossip_debug(GOSSIP_DEV_DEBUG,
                                     "%s: op:%s: op_state:%d: process:%s:\n",
                                     __func__,
                                     get_opname_string(op),
                                     op->op_state,
                                     current->comm);
                }
                spin_unlock(&orangefs_htable_ops_in_progress_lock);
        }
}

module_init(orangefs_init);
module_exit(orangefs_exit);