Mark Fasheh | ccd979b | 2005-12-15 14:31:24 -0800 | [diff] [blame] | 1 | /* -*- mode: c; c-basic-offset: 8; -*- |
| 2 | * vim: noexpandtab sw=8 ts=8 sts=0: |
| 3 | * |
| 4 | * mmap.c |
| 5 | * |
| 6 | * Code to deal with the mess that is clustered mmap. |
| 7 | * |
| 8 | * Copyright (C) 2002, 2004 Oracle. All rights reserved. |
| 9 | * |
| 10 | * This program is free software; you can redistribute it and/or |
| 11 | * modify it under the terms of the GNU General Public |
| 12 | * License as published by the Free Software Foundation; either |
| 13 | * version 2 of the License, or (at your option) any later version. |
| 14 | * |
| 15 | * This program is distributed in the hope that it will be useful, |
| 16 | * but WITHOUT ANY WARRANTY; without even the implied warranty of |
| 17 | * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU |
| 18 | * General Public License for more details. |
| 19 | * |
| 20 | * You should have received a copy of the GNU General Public |
| 21 | * License along with this program; if not, write to the |
| 22 | * Free Software Foundation, Inc., 59 Temple Place - Suite 330, |
| 23 | * Boston, MA 021110-1307, USA. |
| 24 | */ |
| 25 | |
| 26 | #include <linux/fs.h> |
| 27 | #include <linux/types.h> |
| 28 | #include <linux/slab.h> |
| 29 | #include <linux/highmem.h> |
| 30 | #include <linux/pagemap.h> |
| 31 | #include <linux/uio.h> |
| 32 | #include <linux/signal.h> |
| 33 | #include <linux/rbtree.h> |
| 34 | |
| 35 | #define MLOG_MASK_PREFIX ML_FILE_IO |
| 36 | #include <cluster/masklog.h> |
| 37 | |
| 38 | #include "ocfs2.h" |
| 39 | |
Mark Fasheh | 7307de8 | 2007-05-09 15:16:19 -0700 | [diff] [blame] | 40 | #include "aops.h" |
Mark Fasheh | ccd979b | 2005-12-15 14:31:24 -0800 | [diff] [blame] | 41 | #include "dlmglue.h" |
| 42 | #include "file.h" |
| 43 | #include "inode.h" |
| 44 | #include "mmap.h" |
| 45 | |
Mark Fasheh | 7307de8 | 2007-05-09 15:16:19 -0700 | [diff] [blame] | 46 | static inline int ocfs2_vm_op_block_sigs(sigset_t *blocked, sigset_t *oldset) |
| 47 | { |
| 48 | /* The best way to deal with signals in the vm path is |
| 49 | * to block them upfront, rather than allowing the |
| 50 | * locking paths to return -ERESTARTSYS. */ |
| 51 | sigfillset(blocked); |
| 52 | |
| 53 | /* We should technically never get a bad return value |
| 54 | * from sigprocmask */ |
| 55 | return sigprocmask(SIG_BLOCK, blocked, oldset); |
| 56 | } |
| 57 | |
| 58 | static inline int ocfs2_vm_op_unblock_sigs(sigset_t *oldset) |
| 59 | { |
| 60 | return sigprocmask(SIG_SETMASK, oldset, NULL); |
| 61 | } |
| 62 | |
Nick Piggin | d0217ac | 2007-07-19 01:47:03 -0700 | [diff] [blame] | 63 | static int ocfs2_fault(struct vm_area_struct *area, struct vm_fault *vmf) |
Mark Fasheh | ccd979b | 2005-12-15 14:31:24 -0800 | [diff] [blame] | 64 | { |
Mark Fasheh | ccd979b | 2005-12-15 14:31:24 -0800 | [diff] [blame] | 65 | sigset_t blocked, oldset; |
Nick Piggin | d0217ac | 2007-07-19 01:47:03 -0700 | [diff] [blame] | 66 | int error, ret; |
Mark Fasheh | ccd979b | 2005-12-15 14:31:24 -0800 | [diff] [blame] | 67 | |
Nick Piggin | d0217ac | 2007-07-19 01:47:03 -0700 | [diff] [blame] | 68 | mlog_entry("(area=%p, page offset=%lu)\n", area, vmf->pgoff); |
Mark Fasheh | ccd979b | 2005-12-15 14:31:24 -0800 | [diff] [blame] | 69 | |
Nick Piggin | d0217ac | 2007-07-19 01:47:03 -0700 | [diff] [blame] | 70 | error = ocfs2_vm_op_block_sigs(&blocked, &oldset); |
| 71 | if (error < 0) { |
| 72 | mlog_errno(error); |
| 73 | ret = VM_FAULT_SIGBUS; |
Mark Fasheh | ccd979b | 2005-12-15 14:31:24 -0800 | [diff] [blame] | 74 | goto out; |
| 75 | } |
| 76 | |
Nick Piggin | d0217ac | 2007-07-19 01:47:03 -0700 | [diff] [blame] | 77 | ret = filemap_fault(area, vmf); |
Mark Fasheh | ccd979b | 2005-12-15 14:31:24 -0800 | [diff] [blame] | 78 | |
Nick Piggin | d0217ac | 2007-07-19 01:47:03 -0700 | [diff] [blame] | 79 | error = ocfs2_vm_op_unblock_sigs(&oldset); |
| 80 | if (error < 0) |
| 81 | mlog_errno(error); |
Mark Fasheh | ccd979b | 2005-12-15 14:31:24 -0800 | [diff] [blame] | 82 | out: |
Nick Piggin | d0217ac | 2007-07-19 01:47:03 -0700 | [diff] [blame] | 83 | mlog_exit_ptr(vmf->page); |
| 84 | return ret; |
Mark Fasheh | ccd979b | 2005-12-15 14:31:24 -0800 | [diff] [blame] | 85 | } |
| 86 | |
Mark Fasheh | 7307de8 | 2007-05-09 15:16:19 -0700 | [diff] [blame] | 87 | static int __ocfs2_page_mkwrite(struct inode *inode, struct buffer_head *di_bh, |
| 88 | struct page *page) |
| 89 | { |
| 90 | int ret; |
| 91 | struct address_space *mapping = inode->i_mapping; |
Nick Piggin | 1833633 | 2007-07-20 00:31:45 -0700 | [diff] [blame] | 92 | loff_t pos = page_offset(page); |
Mark Fasheh | 7307de8 | 2007-05-09 15:16:19 -0700 | [diff] [blame] | 93 | unsigned int len = PAGE_CACHE_SIZE; |
| 94 | pgoff_t last_index; |
| 95 | struct page *locked_page = NULL; |
| 96 | void *fsdata; |
| 97 | loff_t size = i_size_read(inode); |
| 98 | |
| 99 | /* |
| 100 | * Another node might have truncated while we were waiting on |
| 101 | * cluster locks. |
| 102 | */ |
| 103 | last_index = size >> PAGE_CACHE_SHIFT; |
| 104 | if (page->index > last_index) { |
| 105 | ret = -EINVAL; |
| 106 | goto out; |
| 107 | } |
| 108 | |
| 109 | /* |
| 110 | * The i_size check above doesn't catch the case where nodes |
| 111 | * truncated and then re-extended the file. We'll re-check the |
| 112 | * page mapping after taking the page lock inside of |
| 113 | * ocfs2_write_begin_nolock(). |
| 114 | */ |
| 115 | if (!PageUptodate(page) || page->mapping != inode->i_mapping) { |
Tao Ma | 4c1bbf1 | 2008-10-06 16:59:55 +0800 | [diff] [blame] | 116 | /* |
| 117 | * the page has been umapped in ocfs2_data_downconvert_worker. |
| 118 | * So return 0 here and let VFS retry. |
| 119 | */ |
| 120 | ret = 0; |
Mark Fasheh | 7307de8 | 2007-05-09 15:16:19 -0700 | [diff] [blame] | 121 | goto out; |
| 122 | } |
| 123 | |
| 124 | /* |
| 125 | * Call ocfs2_write_begin() and ocfs2_write_end() to take |
| 126 | * advantage of the allocation code there. We pass a write |
| 127 | * length of the whole page (chopped to i_size) to make sure |
| 128 | * the whole thing is allocated. |
| 129 | * |
| 130 | * Since we know the page is up to date, we don't have to |
| 131 | * worry about ocfs2_write_begin() skipping some buffer reads |
| 132 | * because the "write" would invalidate their data. |
| 133 | */ |
| 134 | if (page->index == last_index) |
| 135 | len = size & ~PAGE_CACHE_MASK; |
| 136 | |
| 137 | ret = ocfs2_write_begin_nolock(mapping, pos, len, 0, &locked_page, |
| 138 | &fsdata, di_bh, page); |
| 139 | if (ret) { |
| 140 | if (ret != -ENOSPC) |
| 141 | mlog_errno(ret); |
| 142 | goto out; |
| 143 | } |
| 144 | |
| 145 | ret = ocfs2_write_end_nolock(mapping, pos, len, len, locked_page, |
| 146 | fsdata); |
| 147 | if (ret < 0) { |
| 148 | mlog_errno(ret); |
| 149 | goto out; |
| 150 | } |
| 151 | BUG_ON(ret != len); |
| 152 | ret = 0; |
| 153 | out: |
| 154 | return ret; |
| 155 | } |
| 156 | |
| 157 | static int ocfs2_page_mkwrite(struct vm_area_struct *vma, struct page *page) |
| 158 | { |
| 159 | struct inode *inode = vma->vm_file->f_path.dentry->d_inode; |
| 160 | struct buffer_head *di_bh = NULL; |
| 161 | sigset_t blocked, oldset; |
| 162 | int ret, ret2; |
| 163 | |
| 164 | ret = ocfs2_vm_op_block_sigs(&blocked, &oldset); |
| 165 | if (ret < 0) { |
| 166 | mlog_errno(ret); |
| 167 | return ret; |
| 168 | } |
| 169 | |
| 170 | /* |
| 171 | * The cluster locks taken will block a truncate from another |
| 172 | * node. Taking the data lock will also ensure that we don't |
| 173 | * attempt page truncation as part of a downconvert. |
| 174 | */ |
Mark Fasheh | e63aecb6 | 2007-10-18 15:30:42 -0700 | [diff] [blame] | 175 | ret = ocfs2_inode_lock(inode, &di_bh, 1); |
Mark Fasheh | 7307de8 | 2007-05-09 15:16:19 -0700 | [diff] [blame] | 176 | if (ret < 0) { |
| 177 | mlog_errno(ret); |
| 178 | goto out; |
| 179 | } |
| 180 | |
| 181 | /* |
| 182 | * The alloc sem should be enough to serialize with |
| 183 | * ocfs2_truncate_file() changing i_size as well as any thread |
| 184 | * modifying the inode btree. |
| 185 | */ |
| 186 | down_write(&OCFS2_I(inode)->ip_alloc_sem); |
| 187 | |
Mark Fasheh | 7307de8 | 2007-05-09 15:16:19 -0700 | [diff] [blame] | 188 | ret = __ocfs2_page_mkwrite(inode, di_bh, page); |
| 189 | |
Mark Fasheh | 7307de8 | 2007-05-09 15:16:19 -0700 | [diff] [blame] | 190 | up_write(&OCFS2_I(inode)->ip_alloc_sem); |
| 191 | |
| 192 | brelse(di_bh); |
Mark Fasheh | e63aecb6 | 2007-10-18 15:30:42 -0700 | [diff] [blame] | 193 | ocfs2_inode_unlock(inode, 1); |
Mark Fasheh | 7307de8 | 2007-05-09 15:16:19 -0700 | [diff] [blame] | 194 | |
| 195 | out: |
| 196 | ret2 = ocfs2_vm_op_unblock_sigs(&oldset); |
| 197 | if (ret2 < 0) |
| 198 | mlog_errno(ret2); |
| 199 | |
| 200 | return ret; |
| 201 | } |
| 202 | |
Mark Fasheh | ccd979b | 2005-12-15 14:31:24 -0800 | [diff] [blame] | 203 | static struct vm_operations_struct ocfs2_file_vm_ops = { |
Nick Piggin | 54cb882 | 2007-07-19 01:46:59 -0700 | [diff] [blame] | 204 | .fault = ocfs2_fault, |
Mark Fasheh | 7307de8 | 2007-05-09 15:16:19 -0700 | [diff] [blame] | 205 | .page_mkwrite = ocfs2_page_mkwrite, |
Mark Fasheh | ccd979b | 2005-12-15 14:31:24 -0800 | [diff] [blame] | 206 | }; |
| 207 | |
Christoph Hellwig | 870f481 | 2006-01-09 20:52:01 -0800 | [diff] [blame] | 208 | int ocfs2_mmap(struct file *file, struct vm_area_struct *vma) |
Mark Fasheh | ccd979b | 2005-12-15 14:31:24 -0800 | [diff] [blame] | 209 | { |
Tiger Yang | 25899de | 2006-11-15 15:49:02 +0800 | [diff] [blame] | 210 | int ret = 0, lock_level = 0; |
Mark Fasheh | ccd979b | 2005-12-15 14:31:24 -0800 | [diff] [blame] | 211 | |
Mark Fasheh | e63aecb6 | 2007-10-18 15:30:42 -0700 | [diff] [blame] | 212 | ret = ocfs2_inode_lock_atime(file->f_dentry->d_inode, |
Tiger Yang | 25899de | 2006-11-15 15:49:02 +0800 | [diff] [blame] | 213 | file->f_vfsmnt, &lock_level); |
| 214 | if (ret < 0) { |
| 215 | mlog_errno(ret); |
| 216 | goto out; |
| 217 | } |
Mark Fasheh | e63aecb6 | 2007-10-18 15:30:42 -0700 | [diff] [blame] | 218 | ocfs2_inode_unlock(file->f_dentry->d_inode, lock_level); |
Tiger Yang | 25899de | 2006-11-15 15:49:02 +0800 | [diff] [blame] | 219 | out: |
Mark Fasheh | ccd979b | 2005-12-15 14:31:24 -0800 | [diff] [blame] | 220 | vma->vm_ops = &ocfs2_file_vm_ops; |
Nick Piggin | d0217ac | 2007-07-19 01:47:03 -0700 | [diff] [blame] | 221 | vma->vm_flags |= VM_CAN_NONLINEAR; |
Mark Fasheh | ccd979b | 2005-12-15 14:31:24 -0800 | [diff] [blame] | 222 | return 0; |
| 223 | } |
| 224 | |