nfsd: Fix oops when parsing a 0 length export
[linux-2.6/linux-acpi-2.6/ibm-acpi-2.6.git] / fs / jfs / file.c
blob2f3f531f36064772dfd4e934847dd5c33fd1cbe4
1 /*
2 * Copyright (C) International Business Machines Corp., 2000-2002
3 * Portions Copyright (C) Christoph Hellwig, 2001-2002
5 * This program is free software; you can redistribute it and/or modify
6 * it under the terms of the GNU General Public License as published by
7 * the Free Software Foundation; either version 2 of the License, or
8 * (at your option) any later version.
10 * This program is distributed in the hope that it will be useful,
11 * but WITHOUT ANY WARRANTY; without even the implied warranty of
12 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See
13 * the GNU General Public License for more details.
15 * You should have received a copy of the GNU General Public License
16 * along with this program; if not, write to the Free Software
17 * Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA
20 #include <linux/mm.h>
21 #include <linux/fs.h>
22 #include <linux/quotaops.h>
23 #include "jfs_incore.h"
24 #include "jfs_inode.h"
25 #include "jfs_dmap.h"
26 #include "jfs_txnmgr.h"
27 #include "jfs_xattr.h"
28 #include "jfs_acl.h"
29 #include "jfs_debug.h"
31 int jfs_fsync(struct file *file, int datasync)
33 struct inode *inode = file->f_mapping->host;
34 int rc = 0;
36 if (!(inode->i_state & I_DIRTY) ||
37 (datasync && !(inode->i_state & I_DIRTY_DATASYNC))) {
38 /* Make sure committed changes hit the disk */
39 jfs_flush_journal(JFS_SBI(inode->i_sb)->log, 1);
40 return rc;
43 rc |= jfs_commit_inode(inode, 1);
45 return rc ? -EIO : 0;
48 static int jfs_open(struct inode *inode, struct file *file)
50 int rc;
52 if ((rc = dquot_file_open(inode, file)))
53 return rc;
56 * We attempt to allow only one "active" file open per aggregate
57 * group. Otherwise, appending to files in parallel can cause
58 * fragmentation within the files.
60 * If the file is empty, it was probably just created and going
61 * to be written to. If it has a size, we'll hold off until the
62 * file is actually grown.
64 if (S_ISREG(inode->i_mode) && file->f_mode & FMODE_WRITE &&
65 (inode->i_size == 0)) {
66 struct jfs_inode_info *ji = JFS_IP(inode);
67 spin_lock_irq(&ji->ag_lock);
68 if (ji->active_ag == -1) {
69 struct jfs_sb_info *jfs_sb = JFS_SBI(inode->i_sb);
70 ji->active_ag = BLKTOAG(addressPXD(&ji->ixpxd), jfs_sb);
71 atomic_inc( &jfs_sb->bmap->db_active[ji->active_ag]);
73 spin_unlock_irq(&ji->ag_lock);
76 return 0;
78 static int jfs_release(struct inode *inode, struct file *file)
80 struct jfs_inode_info *ji = JFS_IP(inode);
82 spin_lock_irq(&ji->ag_lock);
83 if (ji->active_ag != -1) {
84 struct bmap *bmap = JFS_SBI(inode->i_sb)->bmap;
85 atomic_dec(&bmap->db_active[ji->active_ag]);
86 ji->active_ag = -1;
88 spin_unlock_irq(&ji->ag_lock);
90 return 0;
93 int jfs_setattr(struct dentry *dentry, struct iattr *iattr)
95 struct inode *inode = dentry->d_inode;
96 int rc;
98 rc = inode_change_ok(inode, iattr);
99 if (rc)
100 return rc;
102 if (is_quota_modification(inode, iattr))
103 dquot_initialize(inode);
104 if ((iattr->ia_valid & ATTR_UID && iattr->ia_uid != inode->i_uid) ||
105 (iattr->ia_valid & ATTR_GID && iattr->ia_gid != inode->i_gid)) {
106 rc = dquot_transfer(inode, iattr);
107 if (rc)
108 return rc;
111 if ((iattr->ia_valid & ATTR_SIZE) &&
112 iattr->ia_size != i_size_read(inode)) {
113 rc = vmtruncate(inode, iattr->ia_size);
114 if (rc)
115 return rc;
118 setattr_copy(inode, iattr);
119 mark_inode_dirty(inode);
121 if (iattr->ia_valid & ATTR_MODE)
122 rc = jfs_acl_chmod(inode);
123 return rc;
126 const struct inode_operations jfs_file_inode_operations = {
127 .truncate = jfs_truncate,
128 .setxattr = jfs_setxattr,
129 .getxattr = jfs_getxattr,
130 .listxattr = jfs_listxattr,
131 .removexattr = jfs_removexattr,
132 .setattr = jfs_setattr,
133 #ifdef CONFIG_JFS_POSIX_ACL
134 .check_acl = jfs_check_acl,
135 #endif
138 const struct file_operations jfs_file_operations = {
139 .open = jfs_open,
140 .llseek = generic_file_llseek,
141 .write = do_sync_write,
142 .read = do_sync_read,
143 .aio_read = generic_file_aio_read,
144 .aio_write = generic_file_aio_write,
145 .mmap = generic_file_mmap,
146 .splice_read = generic_file_splice_read,
147 .splice_write = generic_file_splice_write,
148 .fsync = jfs_fsync,
149 .release = jfs_release,
150 .unlocked_ioctl = jfs_ioctl,
151 #ifdef CONFIG_COMPAT
152 .compat_ioctl = jfs_compat_ioctl,
153 #endif