lustre/llite/rw24.c

   1 /* -*- mode: c; c-basic-offset: 8; indent-tabs-mode: nil; -*-
   2  * vim:expandtab:shiftwidth=8:tabstop=8:
   3  *
   4  * Lustre Lite I/O page cache for the 2.4 kernel version
   5  *
   6  *  Copyright (c) 2001-2003 Cluster File Systems, Inc.
   7  *
   8  *   This file is part of Lustre, http://www.lustre.org.
   9  *
  10  *   Lustre is free software; you can redistribute it and/or
  11  *   modify it under the terms of version 2 of the GNU General Public
  12  *   License as published by the Free Software Foundation.
  13  *
  14  *   Lustre is distributed in the hope that it will be useful,
  15  *   but WITHOUT ANY WARRANTY; without even the implied warranty of
  16  *   MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  17  *   GNU General Public License for more details.
  18  *
  19  *   You should have received a copy of the GNU General Public License
  20  *   along with Lustre; if not, write to the Free Software
  21  *   Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA.
  22  */
  23
  24 #include <linux/config.h>
  25 #include <linux/kernel.h>
  26 #include <linux/mm.h>
  27 #include <linux/string.h>
  28 #include <linux/stat.h>
  29 #include <linux/errno.h>
  30 #include <linux/smp_lock.h>
  31 #include <linux/unistd.h>
  32 #include <linux/version.h>
  33 #include <asm/system.h>
  34 #include <asm/uaccess.h>
  35
  36 #include <linux/fs.h>
  37 #include <linux/iobuf.h>
  38 #include <linux/stat.h>
  39 #include <asm/uaccess.h>
  40 #include <asm/segment.h>
  41 #include <linux/mm.h>
  42 #include <linux/pagemap.h>
  43 #include <linux/smp_lock.h>
  44
  45 #define DEBUG_SUBSYSTEM S_LLITE
  46
  47 #include <linux/lustre_mds.h>
  48 #include <linux/lustre_lite.h>
  49 #include "llite_internal.h"
  50 #include <linux/lustre_compat25.h>
  51
  52 /* called for each page in a completed rpc.*/
  53 void ll_ap_completion_24(void *data, int cmd, int rc)
  54 {
  55         struct ll_async_page *llap;
  56         struct page *page;
  57
  58         llap = llap_from_cookie(data);
  59         if (IS_ERR(llap)) {
  60                 EXIT;
  61                 return;
  62         }
  63
  64         page = llap->llap_page;
  65         LASSERT(PageLocked(page));
  66
  67         if (rc == 0)  {
  68                 if (cmd == OBD_BRW_READ) {
  69                         if (!llap->llap_defer_uptodate)
  70                                 SetPageUptodate(page);
  71                 } else {
  72                         llap->llap_write_queued = 0;
  73                 }
  74         } else {
  75                 SetPageError(page);
  76         }
  77
  78         LL_CDEBUG_PAGE(page, "io complete, unlocking\n");
  79
  80         unlock_page(page);
  81
  82         if (0 && cmd == OBD_BRW_WRITE) {
  83                 llap_write_complete(page->mapping->host, llap);
  84                 ll_try_done_writing(page->mapping->host);
  85         }
  86
  87         page_cache_release(page);
  88 }
  89
  90 static int ll_writepage_24(struct page *page)
  91 {
  92         struct inode *inode = page->mapping->host;
  93         struct obd_export *exp;
  94         struct ll_async_page *llap;
  95         int rc = 0;
  96         ENTRY;
  97
  98         LASSERT(!PageDirty(page));
  99         LASSERT(PageLocked(page));
 100
 101         exp = ll_i2obdexp(inode);
 102         if (exp == NULL)
 103                 GOTO(out, rc = -EINVAL);
 104
 105         llap = llap_from_page(page);
 106         if (IS_ERR(llap))
 107                 GOTO(out, rc = PTR_ERR(llap));
 108
 109         page_cache_get(page);
 110         if (llap->llap_write_queued) {
 111                 LL_CDEBUG_PAGE(page, "marking urgent\n");
 112                 rc = obd_set_async_flags(exp, ll_i2info(inode)->lli_smd, NULL,
 113                                          llap->llap_cookie, ASYNC_READY |
 114                                          ASYNC_URGENT);
 115         } else {
 116                 llap->llap_write_queued = 1;
 117                 rc = obd_queue_async_io(exp, ll_i2info(inode)->lli_smd, NULL,
 118                                         llap->llap_cookie, OBD_BRW_WRITE, 0, 0,
 119                                         OBD_BRW_CREATE, ASYNC_READY |
 120                                         ASYNC_URGENT);
 121                 if (rc == 0)
 122                         LL_CDEBUG_PAGE(page, "mmap write queued\n");
 123                 else
 124                         llap->llap_write_queued = 0;
 125         }
 126         if (rc)
 127                 page_cache_release(page);
 128 out:
 129         if (rc)
 130                 unlock_page(page);
 131         RETURN(rc);
 132 }
 133
 134 static int ll_direct_IO_24(int rw, struct inode *inode, struct kiobuf *iobuf,
 135                            unsigned long blocknr, int blocksize)
 136 {
 137         struct ll_inode_info *lli = ll_i2info(inode);
 138         struct lov_stripe_md *lsm = lli->lli_smd;
 139         struct brw_page *pga;
 140         struct ptlrpc_request_set *set;
 141         struct obdo oa;
 142         int length, i, flags, rc = 0;
 143         loff_t offset;
 144         ENTRY;
 145
 146         if (!lsm || !lsm->lsm_object_id)
 147                 RETURN(-EBADF);
 148
 149         /* FIXME: io smaller than PAGE_SIZE is broken on ia64 */
 150         if ((iobuf->offset & (PAGE_SIZE - 1)) ||
 151             (iobuf->length & (PAGE_SIZE - 1)))
 152                 RETURN(-EINVAL);
 153
 154         set = ptlrpc_prep_set();
 155         if (set == NULL)
 156                 RETURN(-ENOMEM);
 157
 158         OBD_ALLOC(pga, sizeof(*pga) * iobuf->nr_pages);
 159         if (!pga) {
 160                 ptlrpc_set_destroy(set);
 161                 RETURN(-ENOMEM);
 162         }
 163
 164         flags = (rw == WRITE ? OBD_BRW_CREATE : 0) /* | OBD_BRW_DIRECTIO */;
 165         offset = ((obd_off)blocknr << inode->i_blkbits);
 166         length = iobuf->length;
 167
 168         for (i = 0, length = iobuf->length; length > 0;
 169              length -= pga[i].count, offset += pga[i].count, i++) { /*i last!*/
 170                 pga[i].pg = iobuf->maplist[i];
 171                 pga[i].off = offset;
 172                 /* To the end of the page, or the length, whatever is less */
 173                 pga[i].count = min_t(int, PAGE_SIZE - (offset & ~PAGE_MASK),
 174                                      length);
 175                 pga[i].flag = flags;
 176                 if (rw == READ)
 177                         POISON_PAGE(iobuf->maplist[i], 0x0d);
 178         }
 179
 180         ll_inode_fill_obdo(inode, rw, &oa);
 181
 182         if (rw == WRITE)
 183                 lprocfs_counter_add(ll_i2sbi(inode)->ll_stats,
 184                                     LPROC_LL_DIRECT_WRITE, iobuf->length);
 185         else
 186                 lprocfs_counter_add(ll_i2sbi(inode)->ll_stats,
 187                                     LPROC_LL_DIRECT_READ, iobuf->length);
 188         rc = obd_brw_async(rw == WRITE ? OBD_BRW_WRITE : OBD_BRW_READ,
 189                            ll_i2obdexp(inode), &oa, lsm, iobuf->nr_pages, pga,
 190                            set, NULL);
 191         if (rc) {
 192                 CDEBUG(rc == -ENOSPC ? D_INODE : D_ERROR,
 193                        "error from obd_brw_async: rc = %d\n", rc);
 194         } else {
 195                 rc = ptlrpc_set_wait(set);
 196                 if (rc)
 197                         CERROR("error from callback: rc = %d\n", rc);
 198         }
 199         ptlrpc_set_destroy(set);
 200         if (rc == 0) {
 201                 rc = iobuf->length;
 202                 obdo_to_inode(inode, &oa, OBD_MD_FLBLOCKS);
 203         }
 204
 205         OBD_FREE(pga, sizeof(*pga) * iobuf->nr_pages);
 206         RETURN(rc);
 207 }
 208
 209 struct address_space_operations ll_aops = {
 210         readpage: ll_readpage,
 211         direct_IO: ll_direct_IO_24,
 212         writepage: ll_writepage_24,
 213         prepare_write: ll_prepare_write,
 214         commit_write: ll_commit_write,
 215         removepage: ll_removepage,
 216         sync_page: ll_sync_page,
 217         bmap: NULL
 218 };