lustre/obdecho/echo.c

   1 /* -*- mode: c; c-basic-offset: 8; indent-tabs-mode: nil; -*-
   2  * vim:expandtab:shiftwidth=8:tabstop=8:
   3  *
   4  *  linux/fs/ext2_obd/ext2_obd.c
   5  *
   6  * Copyright (C) 2001  Cluster File Systems, Inc.
   7  *
   8  * This code is issued under the GNU General Public License.
   9  * See the file COPYING in this distribution
  10  *
  11  * by Peter Braam <braam@clusterfs.com>
  12  */
  13
  14 #define EXPORT_SYMTAB
  15
  16 #include <linux/version.h>
  17 #include <linux/module.h>
  18 #include <linux/fs.h>
  19 #include <linux/stat.h>
  20 #include <linux/locks.h>
  21 #include <linux/ext2_fs.h>
  22 #include <linux/quotaops.h>
  23 #include <asm/unistd.h>
  24
  25 #define DEBUG_SUBSYSTEM S_ECHO
  26
  27 #include <linux/obd_support.h>
  28 #include <linux/obd_class.h>
  29 #include <linux/obd_echo.h>
  30
  31 extern struct obd_device obd_dev[MAX_OBD_DEVICES];
  32 static struct obdo OA;
  33 static obd_count GEN;
  34 static long echo_pages = 0;
  35
  36 static int echo_getattr(struct obd_conn *conn, struct obdo *oa)
  37 {
  38         memcpy(oa, &OA, sizeof(*oa));
  39         oa->o_mode = ++GEN;
  40
  41         return 0;
  42 }
  43
  44 int echo_preprw(int cmd, struct obd_conn *conn, int objcount,
  45                 struct obd_ioobj *obj, int niocount, struct niobuf *nb,
  46                 struct niobuf *res)
  47 {
  48         int rc = 0;
  49         int i;
  50
  51         ENTRY;
  52         memset(res, 0, sizeof(*res) * niocount);
  53
  54         CDEBUG(D_CACHE, "%s %d obdos with %d IOs\n",
  55                cmd == OBD_BRW_READ ? "reading" : "writing", objcount, niocount);
  56
  57         for (i = 0; i < objcount; i++, obj++) {
  58                 int j;
  59
  60                 for (j = 0 ; j < obj->ioo_bufcnt ; j++, nb++, res++) {
  61                         unsigned long address;
  62
  63                         address = get_zeroed_page(GFP_KERNEL);
  64                         if (!address) {
  65                                 /* FIXME: cleanup old pages on error */
  66                                 EXIT;
  67                                 rc = -ENOMEM;
  68                         }
  69                         echo_pages++;
  70
  71                         /*
  72                         if (cmd == OBD_BRW_READ) {
  73                                 __u64 *data = address;
  74
  75                                 data[0] = obj->ioo_id;
  76                                 data[1] = j;
  77                                 data[2] = nb->offset;
  78                                 data[3] = nb->len;
  79                         }
  80                         */
  81
  82                         res->addr = address;
  83                         res->offset = nb->offset;
  84                         res->page = virt_to_page(address);
  85                         res->len = PAGE_SIZE;
  86                         // r->flags
  87                 }
  88         }
  89
  90         return rc;
  91 }
  92
  93 int echo_commitrw(int cmd, struct obd_conn *conn, int objcount,
  94                   struct obd_ioobj *obj, int niocount, struct niobuf *res)
  95 {
  96         int i;
  97         int rc = 0;
  98         ENTRY;
  99
 100         CDEBUG(D_CACHE, "%s %d obdos with %d IOs\n",
 101                cmd == OBD_BRW_READ ? "reading" : "writing", objcount, niocount);
 102
 103         for (i = 0; i < objcount; i++, obj++) {
 104                 int j;
 105
 106                 for (j = 0 ; j < obj->ioo_bufcnt ; j++, res++) {
 107                         unsigned long addr;
 108
 109                         if (!res) {
 110                                 /* FIXME: cleanup remaining pages */
 111                                 CERROR("NULL buf, obj %Ld (%d), buf %d/%d\n",
 112                                         obj->ioo_id, i, j, obj->ioo_bufcnt);
 113                                 rc = -EINVAL;
 114                         }
 115
 116                         addr = res->addr;
 117                         if (!addr || !kern_addr_valid(addr)) {
 118                                 /* FIXME: cleanup remaining pages */
 119                                 CERROR("bad addr %lx, id %Ld (%d), buf %d/%d\n",
 120                                        addr, obj->ioo_id, i, j,obj->ioo_bufcnt);
 121                                 rc = -EINVAL;
 122                         }
 123
 124                         free_pages(addr, 0);
 125                         echo_pages--;
 126                 }
 127         }
 128         CDEBUG(D_MALLOC, "%ld pages remain after commit\n", echo_pages);
 129         return rc;
 130 }
 131
 132 struct obd_ops echo_obd_ops = {
 133         o_connect:     gen_connect,
 134         o_disconnect:  gen_disconnect,
 135         o_getattr:     echo_getattr,
 136         o_preprw:      echo_preprw,
 137         o_commitrw:    echo_commitrw,
 138 };
 139
 140
 141 static int __init obdecho_init(void)
 142 {
 143         printk(KERN_INFO "Echo OBD driver  v0.001, braam@clusterfs.com\n");
 144
 145         return obd_register_type(&echo_obd_ops, OBD_ECHO_DEVICENAME);
 146 }
 147
 148 static void __exit obdecho_exit(void)
 149 {
 150         CERROR("%ld prep/commitrw pages leaked\n", echo_pages);
 151         obd_unregister_type(OBD_ECHO_DEVICENAME);
 152 }
 153
 154 MODULE_AUTHOR("Peter J. Braam <braam@clusterfs.com>");
 155 MODULE_DESCRIPTION("Lustre Testing Echo OBD driver v1.0");
 156 MODULE_LICENSE("GPL");
 157
 158 module_init(obdecho_init);
 159 module_exit(obdecho_exit);