1 /*
2  * Copyright 2000-2002 by Hans Reiser, licensing governed by reiserfs/README
3  */
4 
5 
6 #include <linux/sched.h>
7 #include <linux/reiserfs_fs.h>
8 #include <linux/smp_lock.h>
9 
10 /*
11 ** We pack the tails of files on file close, not at the time they are written.
12 ** This implies an unnecessary copy of the tail and an unnecessary indirect item
13 ** insertion/balancing, for files that are written in one write.
14 ** It avoids unnecessary tail packings (balances) for files that are written in
15 ** multiple writes and are small enough to have tails.
16 **
17 ** file_release is called by the VFS layer when the file is closed.  If
18 ** this is the last open file descriptor, and the file
19 ** small enough to have a tail, and the tail is currently in an
20 ** unformatted node, the tail is converted back into a direct item.
21 **
22 ** We use reiserfs_truncate_file to pack the tail, since it already has
23 ** all the conditions coded.
24 */
reiserfs_file_release(struct inode * inode,struct file * filp)25 static int reiserfs_file_release (struct inode * inode, struct file * filp)
26 {
27 
28     struct reiserfs_transaction_handle th ;
29     int windex ;
30 
31     if (!S_ISREG (inode->i_mode))
32 	BUG ();
33 
34     /* fast out for when nothing needs to be done */
35     if ((atomic_read(&inode->i_count) > 1 ||
36          !(inode->u.reiserfs_i.i_flags & i_pack_on_close_mask) ||
37          !tail_has_to_be_packed(inode))       &&
38 	inode->u.reiserfs_i.i_prealloc_count <= 0) {
39 	return 0;
40     }
41 
42     lock_kernel() ;
43     down (&inode->i_sem);
44     journal_begin(&th, inode->i_sb, JOURNAL_PER_BALANCE_CNT * 3) ;
45     reiserfs_update_inode_transaction(inode) ;
46 
47 #ifdef REISERFS_PREALLOCATE
48     reiserfs_discard_prealloc (&th, inode);
49 #endif
50     journal_end(&th, inode->i_sb, JOURNAL_PER_BALANCE_CNT * 3) ;
51 
52     if (atomic_read(&inode->i_count) <= 1 &&
53 	(inode->u.reiserfs_i.i_flags & i_pack_on_close_mask) &&
54         tail_has_to_be_packed (inode)) {
55 	/* if regular file is released by last holder and it has been
56 	   appended (we append by unformatted node only) or its direct
57 	   item(s) had to be converted, then it may have to be
58 	   indirect2direct converted */
59 	windex = push_journal_writer("file_release") ;
60 	reiserfs_truncate_file(inode, 0) ;
61 	pop_journal_writer(windex) ;
62     }
63     up (&inode->i_sem);
64     unlock_kernel() ;
65     return 0;
66 }
67 
reiserfs_vfs_truncate_file(struct inode * inode)68 static void reiserfs_vfs_truncate_file(struct inode *inode) {
69     reiserfs_truncate_file(inode, 1) ;
70 }
71 
72 /* Sync a reiserfs file. */
reiserfs_sync_file(struct file * p_s_filp,struct dentry * p_s_dentry,int datasync)73 static int reiserfs_sync_file(
74 			      struct file   * p_s_filp,
75 			      struct dentry * p_s_dentry,
76 			      int datasync
77 			      ) {
78   struct inode * p_s_inode = p_s_dentry->d_inode;
79   int n_err;
80 
81   lock_kernel() ;
82 
83   if (!S_ISREG(p_s_inode->i_mode))
84       BUG ();
85 
86   n_err = fsync_inode_buffers(p_s_inode) ;
87   n_err |= fsync_inode_data_buffers(p_s_inode);
88   reiserfs_commit_for_inode(p_s_inode) ;
89   unlock_kernel() ;
90   return ( n_err < 0 ) ? -EIO : 0;
91 }
92 
reiserfs_setattr(struct dentry * dentry,struct iattr * attr)93 static int reiserfs_setattr(struct dentry *dentry, struct iattr *attr) {
94     struct inode *inode = dentry->d_inode ;
95     int error ;
96     if (attr->ia_valid & ATTR_SIZE) {
97 	/* version 2 items will be caught by the s_maxbytes check
98 	** done for us in vmtruncate
99 	*/
100 	if (get_inode_item_key_version(inode) == KEY_FORMAT_3_5 &&
101 	    attr->ia_size > MAX_NON_LFS)
102             return -EFBIG ;
103 
104 	/* fill in hole pointers in the expanding truncate case. */
105         if (attr->ia_size > inode->i_size) {
106 	    error = generic_cont_expand(inode, attr->ia_size) ;
107 	    if (inode->u.reiserfs_i.i_prealloc_count > 0) {
108 		struct reiserfs_transaction_handle th ;
109 		/* we're changing at most 2 bitmaps, inode + super */
110 		journal_begin(&th, inode->i_sb, 4) ;
111 		reiserfs_discard_prealloc (&th, inode);
112 		journal_end(&th, inode->i_sb, 4) ;
113 	    }
114 	    if (error)
115 	        return error ;
116 	}
117     }
118 
119     if ((((attr->ia_valid & ATTR_UID) && (attr->ia_uid & ~0xffff)) ||
120 	 ((attr->ia_valid & ATTR_GID) && (attr->ia_gid & ~0xffff))) &&
121 	(get_inode_sd_version (inode) == STAT_DATA_V1))
122 		/* stat data of format v3.5 has 16 bit uid and gid */
123 	    return -EINVAL;
124 
125     error = inode_change_ok(inode, attr) ;
126     if (!error)
127         inode_setattr(inode, attr) ;
128 
129     return error ;
130 }
131 
132 struct file_operations reiserfs_file_operations = {
133     read:	generic_file_read,
134     write:	generic_file_write,
135     ioctl:	reiserfs_ioctl,
136     mmap:	generic_file_mmap,
137     release:	reiserfs_file_release,
138     fsync:	reiserfs_sync_file,
139 };
140 
141 
142 struct  inode_operations reiserfs_file_inode_operations = {
143     truncate:	reiserfs_vfs_truncate_file,
144     setattr:    reiserfs_setattr,
145 };
146 
147 
148