xref: /linux/fs/ufs/util.c (revision 293d5b43948309434568f4dcbb36cce4c3c51bd5)
1 /*
2  *  linux/fs/ufs/util.c
3  *
4  * Copyright (C) 1998
5  * Daniel Pirkl <daniel.pirkl@email.cz>
6  * Charles University, Faculty of Mathematics and Physics
7  */
8 
9 #include <linux/string.h>
10 #include <linux/slab.h>
11 #include <linux/buffer_head.h>
12 
13 #include "ufs_fs.h"
14 #include "ufs.h"
15 #include "swab.h"
16 #include "util.h"
17 
18 struct ufs_buffer_head * _ubh_bread_ (struct ufs_sb_private_info * uspi,
19 	struct super_block *sb, u64 fragment, u64 size)
20 {
21 	struct ufs_buffer_head * ubh;
22 	unsigned i, j ;
23 	u64  count = 0;
24 	if (size & ~uspi->s_fmask)
25 		return NULL;
26 	count = size >> uspi->s_fshift;
27 	if (count > UFS_MAXFRAG)
28 		return NULL;
29 	ubh = kmalloc (sizeof (struct ufs_buffer_head), GFP_NOFS);
30 	if (!ubh)
31 		return NULL;
32 	ubh->fragment = fragment;
33 	ubh->count = count;
34 	for (i = 0; i < count; i++)
35 		if (!(ubh->bh[i] = sb_bread(sb, fragment + i)))
36 			goto failed;
37 	for (; i < UFS_MAXFRAG; i++)
38 		ubh->bh[i] = NULL;
39 	return ubh;
40 failed:
41 	for (j = 0; j < i; j++)
42 		brelse (ubh->bh[j]);
43 	kfree(ubh);
44 	return NULL;
45 }
46 
47 struct ufs_buffer_head * ubh_bread_uspi (struct ufs_sb_private_info * uspi,
48 	struct super_block *sb, u64 fragment, u64 size)
49 {
50 	unsigned i, j;
51 	u64 count = 0;
52 	if (size & ~uspi->s_fmask)
53 		return NULL;
54 	count = size >> uspi->s_fshift;
55 	if (count <= 0 || count > UFS_MAXFRAG)
56 		return NULL;
57 	USPI_UBH(uspi)->fragment = fragment;
58 	USPI_UBH(uspi)->count = count;
59 	for (i = 0; i < count; i++)
60 		if (!(USPI_UBH(uspi)->bh[i] = sb_bread(sb, fragment + i)))
61 			goto failed;
62 	for (; i < UFS_MAXFRAG; i++)
63 		USPI_UBH(uspi)->bh[i] = NULL;
64 	return USPI_UBH(uspi);
65 failed:
66 	for (j = 0; j < i; j++)
67 		brelse (USPI_UBH(uspi)->bh[j]);
68 	return NULL;
69 }
70 
71 void ubh_brelse (struct ufs_buffer_head * ubh)
72 {
73 	unsigned i;
74 	if (!ubh)
75 		return;
76 	for (i = 0; i < ubh->count; i++)
77 		brelse (ubh->bh[i]);
78 	kfree (ubh);
79 }
80 
81 void ubh_brelse_uspi (struct ufs_sb_private_info * uspi)
82 {
83 	unsigned i;
84 	if (!USPI_UBH(uspi))
85 		return;
86 	for ( i = 0; i < USPI_UBH(uspi)->count; i++ ) {
87 		brelse (USPI_UBH(uspi)->bh[i]);
88 		USPI_UBH(uspi)->bh[i] = NULL;
89 	}
90 }
91 
92 void ubh_mark_buffer_dirty (struct ufs_buffer_head * ubh)
93 {
94 	unsigned i;
95 	if (!ubh)
96 		return;
97 	for ( i = 0; i < ubh->count; i++ )
98 		mark_buffer_dirty (ubh->bh[i]);
99 }
100 
101 void ubh_mark_buffer_uptodate (struct ufs_buffer_head * ubh, int flag)
102 {
103 	unsigned i;
104 	if (!ubh)
105 		return;
106 	if (flag) {
107 		for ( i = 0; i < ubh->count; i++ )
108 			set_buffer_uptodate (ubh->bh[i]);
109 	} else {
110 		for ( i = 0; i < ubh->count; i++ )
111 			clear_buffer_uptodate (ubh->bh[i]);
112 	}
113 }
114 
115 void ubh_sync_block(struct ufs_buffer_head *ubh)
116 {
117 	if (ubh) {
118 		unsigned i;
119 
120 		for (i = 0; i < ubh->count; i++)
121 			write_dirty_buffer(ubh->bh[i], 0);
122 
123 		for (i = 0; i < ubh->count; i++)
124 			wait_on_buffer(ubh->bh[i]);
125 	}
126 }
127 
128 void ubh_bforget (struct ufs_buffer_head * ubh)
129 {
130 	unsigned i;
131 	if (!ubh)
132 		return;
133 	for ( i = 0; i < ubh->count; i++ ) if ( ubh->bh[i] )
134 		bforget (ubh->bh[i]);
135 }
136 
137 int ubh_buffer_dirty (struct ufs_buffer_head * ubh)
138 {
139 	unsigned i;
140 	unsigned result = 0;
141 	if (!ubh)
142 		return 0;
143 	for ( i = 0; i < ubh->count; i++ )
144 		result |= buffer_dirty(ubh->bh[i]);
145 	return result;
146 }
147 
148 void _ubh_ubhcpymem_(struct ufs_sb_private_info * uspi,
149 	unsigned char * mem, struct ufs_buffer_head * ubh, unsigned size)
150 {
151 	unsigned len, bhno;
152 	if (size > (ubh->count << uspi->s_fshift))
153 		size = ubh->count << uspi->s_fshift;
154 	bhno = 0;
155 	while (size) {
156 		len = min_t(unsigned int, size, uspi->s_fsize);
157 		memcpy (mem, ubh->bh[bhno]->b_data, len);
158 		mem += uspi->s_fsize;
159 		size -= len;
160 		bhno++;
161 	}
162 }
163 
164 void _ubh_memcpyubh_(struct ufs_sb_private_info * uspi,
165 	struct ufs_buffer_head * ubh, unsigned char * mem, unsigned size)
166 {
167 	unsigned len, bhno;
168 	if (size > (ubh->count << uspi->s_fshift))
169 		size = ubh->count << uspi->s_fshift;
170 	bhno = 0;
171 	while (size) {
172 		len = min_t(unsigned int, size, uspi->s_fsize);
173 		memcpy (ubh->bh[bhno]->b_data, mem, len);
174 		mem += uspi->s_fsize;
175 		size -= len;
176 		bhno++;
177 	}
178 }
179 
180 dev_t
181 ufs_get_inode_dev(struct super_block *sb, struct ufs_inode_info *ufsi)
182 {
183 	__u32 fs32;
184 	dev_t dev;
185 
186 	if ((UFS_SB(sb)->s_flags & UFS_ST_MASK) == UFS_ST_SUNx86)
187 		fs32 = fs32_to_cpu(sb, ufsi->i_u1.i_data[1]);
188 	else
189 		fs32 = fs32_to_cpu(sb, ufsi->i_u1.i_data[0]);
190 	switch (UFS_SB(sb)->s_flags & UFS_ST_MASK) {
191 	case UFS_ST_SUNx86:
192 	case UFS_ST_SUN:
193 		if ((fs32 & 0xffff0000) == 0 ||
194 		    (fs32 & 0xffff0000) == 0xffff0000)
195 			dev = old_decode_dev(fs32 & 0x7fff);
196 		else
197 			dev = MKDEV(sysv_major(fs32), sysv_minor(fs32));
198 		break;
199 
200 	default:
201 		dev = old_decode_dev(fs32);
202 		break;
203 	}
204 	return dev;
205 }
206 
207 void
208 ufs_set_inode_dev(struct super_block *sb, struct ufs_inode_info *ufsi, dev_t dev)
209 {
210 	__u32 fs32;
211 
212 	switch (UFS_SB(sb)->s_flags & UFS_ST_MASK) {
213 	case UFS_ST_SUNx86:
214 	case UFS_ST_SUN:
215 		fs32 = sysv_encode_dev(dev);
216 		if ((fs32 & 0xffff8000) == 0) {
217 			fs32 = old_encode_dev(dev);
218 		}
219 		break;
220 
221 	default:
222 		fs32 = old_encode_dev(dev);
223 		break;
224 	}
225 	if ((UFS_SB(sb)->s_flags & UFS_ST_MASK) == UFS_ST_SUNx86)
226 		ufsi->i_u1.i_data[1] = cpu_to_fs32(sb, fs32);
227 	else
228 		ufsi->i_u1.i_data[0] = cpu_to_fs32(sb, fs32);
229 }
230 
231 /**
232  * ufs_get_locked_page() - locate, pin and lock a pagecache page, if not exist
233  * read it from disk.
234  * @mapping: the address_space to search
235  * @index: the page index
236  *
237  * Locates the desired pagecache page, if not exist we'll read it,
238  * locks it, increments its reference
239  * count and returns its address.
240  *
241  */
242 
243 struct page *ufs_get_locked_page(struct address_space *mapping,
244 				 pgoff_t index)
245 {
246 	struct page *page;
247 
248 	page = find_lock_page(mapping, index);
249 	if (!page) {
250 		page = read_mapping_page(mapping, index, NULL);
251 
252 		if (IS_ERR(page)) {
253 			printk(KERN_ERR "ufs_change_blocknr: "
254 			       "read_mapping_page error: ino %lu, index: %lu\n",
255 			       mapping->host->i_ino, index);
256 			goto out;
257 		}
258 
259 		lock_page(page);
260 
261 		if (unlikely(page->mapping == NULL)) {
262 			/* Truncate got there first */
263 			unlock_page(page);
264 			put_page(page);
265 			page = NULL;
266 			goto out;
267 		}
268 
269 		if (!PageUptodate(page) || PageError(page)) {
270 			unlock_page(page);
271 			put_page(page);
272 
273 			printk(KERN_ERR "ufs_change_blocknr: "
274 			       "can not read page: ino %lu, index: %lu\n",
275 			       mapping->host->i_ino, index);
276 
277 			page = ERR_PTR(-EIO);
278 		}
279 	}
280 out:
281 	return page;
282 }
283