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         llap->llap_queued = 0;
  65         page = llap->llap_page;
  66
  67         LASSERT(PageLocked(page));
  68
  69         if (rc == 0)  {
  70                 if (cmd == OBD_BRW_READ)
  71                         SetPageUptodate(page);
  72         } else {
  73                 SetPageError(page);
  74         }
  75
  76         LL_CDEBUG_PAGE(page, "io complete, unlocking\n");
  77
  78         unlock_page(page);
  79
  80         if (0 && cmd == OBD_BRW_WRITE) {
  81                 llap_write_complete(page->mapping->host, llap);
  82                 ll_try_done_writing(page->mapping->host);
  83         }
  84
  85         page_cache_release(page);
  86 }
  87
  88 static int ll_writepage_24(struct page *page)
  89 {
  90         struct inode *inode = page->mapping->host;
  91         struct obd_export *exp;
  92         struct ll_async_page *llap;
  93         int rc = 0;
  94         ENTRY;
  95
  96         LASSERT(!PageDirty(page));
  97         LASSERT(PageLocked(page));
  98
  99         exp = ll_i2obdexp(inode);
 100         if (exp == NULL)
 101                 GOTO(out, rc = -EINVAL);
 102
 103         llap = llap_from_page(page);
 104         if (IS_ERR(llap))
 105                 GOTO(out, rc = PTR_ERR(llap));
 106
 107         page_cache_get(page);
 108         if (llap->llap_queued) {
 109                 LL_CDEBUG_PAGE(page, "marking urgent\n");
 110                 rc = obd_set_async_flags(exp, ll_i2info(inode)->lli_smd, NULL,
 111                                          llap->llap_cookie, ASYNC_READY |
 112                                          ASYNC_URGENT);
 113         } else {
 114                 rc = obd_queue_async_io(exp, ll_i2info(inode)->lli_smd, NULL,
 115                                         llap->llap_cookie, OBD_BRW_WRITE, 0, 0,
 116                                         OBD_BRW_CREATE, ASYNC_READY |
 117                                         ASYNC_URGENT);
 118                 if (rc == 0) {
 119                         LL_CDEBUG_PAGE(page, "mmap write queued\n");
 120                         llap->llap_queued = 1;
 121                 }
 122         }
 123         if (rc)
 124                 page_cache_release(page);
 125 out:
 126         if (rc)
 127                 unlock_page(page);
 128         RETURN(rc);
 129 }
 130
 131 static int ll_direct_IO_24(int rw, struct inode *inode, struct kiobuf *iobuf,
 132                            unsigned long blocknr, int blocksize)
 133 {
 134         struct ll_inode_info *lli = ll_i2info(inode);
 135         struct lov_stripe_md *lsm = lli->lli_smd;
 136         struct brw_page *pga;
 137         struct ptlrpc_request_set *set;
 138         struct obdo oa;
 139         int length, i, flags, rc = 0;
 140         loff_t offset;
 141         ENTRY;
 142
 143         if (!lsm || !lsm->lsm_object_id)
 144                 RETURN(-EBADF);
 145
 146         /* FIXME: io smaller than PAGE_SIZE is broken on ia64 */
 147         if ((iobuf->offset & (PAGE_SIZE - 1)) ||
 148             (iobuf->length & (PAGE_SIZE - 1)))
 149                 RETURN(-EINVAL);
 150
 151         set = ptlrpc_prep_set();
 152         if (set == NULL)
 153                 RETURN(-ENOMEM);
 154
 155         OBD_ALLOC(pga, sizeof(*pga) * iobuf->nr_pages);
 156         if (!pga) {
 157                 ptlrpc_set_destroy(set);
 158                 RETURN(-ENOMEM);
 159         }
 160
 161         flags = (rw == WRITE ? OBD_BRW_CREATE : 0) /* | OBD_BRW_DIRECTIO */;
 162         offset = ((obd_off)blocknr << inode->i_blkbits);
 163         length = iobuf->length;
 164
 165         for (i = 0, length = iobuf->length; length > 0;
 166              length -= pga[i].count, offset += pga[i].count, i++) { /*i last!*/
 167                 pga[i].pg = iobuf->maplist[i];
 168                 pga[i].off = offset;
 169                 /* To the end of the page, or the length, whatever is less */
 170                 pga[i].count = min_t(int, PAGE_SIZE - (offset & ~PAGE_MASK),
 171                                      length);
 172                 pga[i].flag = flags;
 173                 if (rw == READ)
 174                         POISON_PAGE(iobuf->maplist[i], 0x0d);
 175         }
 176
 177         ll_inode_fill_obdo(inode, rw, &oa);
 178
 179         if (rw == WRITE)
 180                 lprocfs_counter_add(ll_i2sbi(inode)->ll_stats,
 181                                     LPROC_LL_DIRECT_WRITE, iobuf->length);
 182         else
 183                 lprocfs_counter_add(ll_i2sbi(inode)->ll_stats,
 184                                     LPROC_LL_DIRECT_READ, iobuf->length);
 185         rc = obd_brw_async(rw == WRITE ? OBD_BRW_WRITE : OBD_BRW_READ,
 186                            ll_i2obdexp(inode), &oa, lsm, iobuf->nr_pages, pga,
 187                            set, NULL);
 188         if (rc) {
 189                 CDEBUG(rc == -ENOSPC ? D_INODE : D_ERROR,
 190                        "error from obd_brw_async: rc = %d\n", rc);
 191         } else {
 192                 rc = ptlrpc_set_wait(set);
 193                 if (rc)
 194                         CERROR("error from callback: rc = %d\n", rc);
 195         }
 196         ptlrpc_set_destroy(set);
 197         if (rc == 0) {
 198                 rc = iobuf->length;
 199                 obdo_to_inode(inode, &oa, OBD_MD_FLBLOCKS);
 200         }
 201
 202         OBD_FREE(pga, sizeof(*pga) * iobuf->nr_pages);
 203         RETURN(rc);
 204 }
 205
 206 struct address_space_operations ll_aops = {
 207         readpage: ll_readpage,
 208         direct_IO: ll_direct_IO_24,
 209         writepage: ll_writepage_24,
 210         prepare_write: ll_prepare_write,
 211         commit_write: ll_commit_write,
 212         removepage: ll_removepage,
 213         bmap: NULL
 214 };