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 #ifdef HAVE_DIO_FILE
  53 static int ll_direct_IO_24(int rw, struct file *file, struct kiobuf *iobuf,
  54                            unsigned long blocknr, int blocksize)
  55 #else
  56 static int ll_direct_IO_24(int rw, struct inode *inode, struct kiobuf *iobuf,
  57                            unsigned long blocknr, int blocksize)
  58 #endif
  59 {
  60 #ifdef HAVE_DIO_FILE
  61         struct inode *inode = file->f_dentry->d_inode;
  62 #endif
  63         struct ll_inode_info *lli = ll_i2info(inode);
  64         struct lov_stripe_md *lsm = lli->lli_smd;
  65         struct brw_page *pga;
  66         struct ptlrpc_request_set *set;
  67         struct obdo *oa = NULL;
  68         int length, i, flags, rc = 0;
  69         loff_t offset;
  70         ENTRY;
  71
  72         if (!lsm || !lsm->lsm_object_id)
  73                 RETURN(-EBADF);
  74
  75         set = ptlrpc_prep_set();
  76         if (set == NULL)
  77                 RETURN(-ENOMEM);
  78
  79         OBD_ALLOC(pga, sizeof(*pga) * iobuf->nr_pages);
  80         if (!pga) {
  81                 ptlrpc_set_destroy(set);
  82                 RETURN(-ENOMEM);
  83         }
  84
  85         flags = 0 /* | OBD_BRW_DIRECTIO */;
  86         offset = ((obd_off)blocknr * blocksize);
  87         length = iobuf->length;
  88         pga[0].page_offset = iobuf->offset;
  89         LASSERT(iobuf->offset < PAGE_SIZE);
  90
  91         for (i = 0, length = iobuf->length; length > 0;
  92              length -= pga[i].count, offset += pga[i].count, i++) { /*i last!*/
  93                 pga[i].pg = iobuf->maplist[i];
  94                 pga[i].disk_offset = offset;
  95                 /* To the end of the page, or the length, whatever is less */
  96                 pga[i].count = min_t(int, PAGE_SIZE - pga[i].page_offset,
  97                                      length);
  98                 pga[i].flag = flags;
  99                 if (rw == READ)
 100                         POISON_PAGE(iobuf->maplist[i], 0x0d);
 101         }
 102
 103         oa = obdo_alloc();
 104         if (oa == NULL) {
 105                 ptlrpc_set_destroy(set);
 106                 GOTO(out_free_pga, -ENOMEM);
 107         }
 108         ll_inode_fill_obdo(inode, rw, oa);
 109
 110         if (rw == WRITE)
 111                 lprocfs_counter_add(ll_i2sbi(inode)->ll_stats,
 112                                     LPROC_LL_DIRECT_WRITE, iobuf->length);
 113         else
 114                 lprocfs_counter_add(ll_i2sbi(inode)->ll_stats,
 115                                     LPROC_LL_DIRECT_READ, iobuf->length);
 116         rc = obd_brw_async(rw == WRITE ? OBD_BRW_WRITE : OBD_BRW_READ,
 117                            ll_i2dtexp(inode), oa, lsm, iobuf->nr_pages, pga,
 118                            set, NULL);
 119         if (rc) {
 120                 CDEBUG(rc == -ENOSPC ? D_INODE : D_ERROR,
 121                        "error from obd_brw_async: rc = %d\n", rc);
 122         } else {
 123                 rc = ptlrpc_set_wait(set);
 124                 if (rc)
 125                         CERROR("error from callback: rc = %d\n", rc);
 126         }
 127         ptlrpc_set_destroy(set);
 128         if (rc == 0 && rw == WRITE) {
 129                 void lov_increase_kms(struct obd_export *,
 130                                       struct lov_stripe_md *, obd_off size);
 131                 obd_off size = offset + length;
 132                 lov_increase_kms(ll_i2dtexp(inode), lsm, size);
 133                 if (size > inode->i_size)
 134                         inode->i_size = size;
 135         }
 136         if (rc == 0) {
 137                 rc = iobuf->length;
 138                 obdo_to_inode(inode, oa, OBD_MD_FLBLOCKS);
 139         }
 140         obdo_free(oa);
 141         EXIT;
 142 out_free_pga:
 143         OBD_FREE(pga, sizeof(*pga) * iobuf->nr_pages);
 144         return rc;
 145 }
 146
 147 struct address_space_operations ll_aops = {
 148         .readpage       = ll_readpage,
 149         .direct_IO      = ll_direct_IO_24,
 150         .writepage      = ll_writepage,
 151         .prepare_write  = ll_prepare_write,
 152         .commit_write   = ll_commit_write,
 153         .removepage     = ll_removepage,
 154         .sync_page      = NULL,
 155         .bmap           = NULL
 156 };