xref: /openbmc/linux/fs/ufs/util.c (revision 63dc02bd)
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 = (struct ufs_buffer_head *)
30 		kmalloc (sizeof (struct ufs_buffer_head), GFP_NOFS);
31 	if (!ubh)
32 		return NULL;
33 	ubh->fragment = fragment;
34 	ubh->count = count;
35 	for (i = 0; i < count; i++)
36 		if (!(ubh->bh[i] = sb_bread(sb, fragment + i)))
37 			goto failed;
38 	for (; i < UFS_MAXFRAG; i++)
39 		ubh->bh[i] = NULL;
40 	return ubh;
41 failed:
42 	for (j = 0; j < i; j++)
43 		brelse (ubh->bh[j]);
44 	kfree(ubh);
45 	return NULL;
46 }
47 
48 struct ufs_buffer_head * ubh_bread_uspi (struct ufs_sb_private_info * uspi,
49 	struct super_block *sb, u64 fragment, u64 size)
50 {
51 	unsigned i, j;
52 	u64 count = 0;
53 	if (size & ~uspi->s_fmask)
54 		return NULL;
55 	count = size >> uspi->s_fshift;
56 	if (count <= 0 || count > UFS_MAXFRAG)
57 		return NULL;
58 	USPI_UBH(uspi)->fragment = fragment;
59 	USPI_UBH(uspi)->count = count;
60 	for (i = 0; i < count; i++)
61 		if (!(USPI_UBH(uspi)->bh[i] = sb_bread(sb, fragment + i)))
62 			goto failed;
63 	for (; i < UFS_MAXFRAG; i++)
64 		USPI_UBH(uspi)->bh[i] = NULL;
65 	return USPI_UBH(uspi);
66 failed:
67 	for (j = 0; j < i; j++)
68 		brelse (USPI_UBH(uspi)->bh[j]);
69 	return NULL;
70 }
71 
72 void ubh_brelse (struct ufs_buffer_head * ubh)
73 {
74 	unsigned i;
75 	if (!ubh)
76 		return;
77 	for (i = 0; i < ubh->count; i++)
78 		brelse (ubh->bh[i]);
79 	kfree (ubh);
80 }
81 
82 void ubh_brelse_uspi (struct ufs_sb_private_info * uspi)
83 {
84 	unsigned i;
85 	if (!USPI_UBH(uspi))
86 		return;
87 	for ( i = 0; i < USPI_UBH(uspi)->count; i++ ) {
88 		brelse (USPI_UBH(uspi)->bh[i]);
89 		USPI_UBH(uspi)->bh[i] = NULL;
90 	}
91 }
92 
93 void ubh_mark_buffer_dirty (struct ufs_buffer_head * ubh)
94 {
95 	unsigned i;
96 	if (!ubh)
97 		return;
98 	for ( i = 0; i < ubh->count; i++ )
99 		mark_buffer_dirty (ubh->bh[i]);
100 }
101 
102 void ubh_mark_buffer_uptodate (struct ufs_buffer_head * ubh, int flag)
103 {
104 	unsigned i;
105 	if (!ubh)
106 		return;
107 	if (flag) {
108 		for ( i = 0; i < ubh->count; i++ )
109 			set_buffer_uptodate (ubh->bh[i]);
110 	} else {
111 		for ( i = 0; i < ubh->count; i++ )
112 			clear_buffer_uptodate (ubh->bh[i]);
113 	}
114 }
115 
116 void ubh_sync_block(struct ufs_buffer_head *ubh)
117 {
118 	if (ubh) {
119 		unsigned i;
120 
121 		for (i = 0; i < ubh->count; i++)
122 			write_dirty_buffer(ubh->bh[i], WRITE);
123 
124 		for (i = 0; i < ubh->count; i++)
125 			wait_on_buffer(ubh->bh[i]);
126 	}
127 }
128 
129 void ubh_bforget (struct ufs_buffer_head * ubh)
130 {
131 	unsigned i;
132 	if (!ubh)
133 		return;
134 	for ( i = 0; i < ubh->count; i++ ) if ( ubh->bh[i] )
135 		bforget (ubh->bh[i]);
136 }
137 
138 int ubh_buffer_dirty (struct ufs_buffer_head * ubh)
139 {
140 	unsigned i;
141 	unsigned result = 0;
142 	if (!ubh)
143 		return 0;
144 	for ( i = 0; i < ubh->count; i++ )
145 		result |= buffer_dirty(ubh->bh[i]);
146 	return result;
147 }
148 
149 void _ubh_ubhcpymem_(struct ufs_sb_private_info * uspi,
150 	unsigned char * mem, struct ufs_buffer_head * ubh, unsigned size)
151 {
152 	unsigned len, bhno;
153 	if (size > (ubh->count << uspi->s_fshift))
154 		size = ubh->count << uspi->s_fshift;
155 	bhno = 0;
156 	while (size) {
157 		len = min_t(unsigned int, size, uspi->s_fsize);
158 		memcpy (mem, ubh->bh[bhno]->b_data, len);
159 		mem += uspi->s_fsize;
160 		size -= len;
161 		bhno++;
162 	}
163 }
164 
165 void _ubh_memcpyubh_(struct ufs_sb_private_info * uspi,
166 	struct ufs_buffer_head * ubh, unsigned char * mem, unsigned size)
167 {
168 	unsigned len, bhno;
169 	if (size > (ubh->count << uspi->s_fshift))
170 		size = ubh->count << uspi->s_fshift;
171 	bhno = 0;
172 	while (size) {
173 		len = min_t(unsigned int, size, uspi->s_fsize);
174 		memcpy (ubh->bh[bhno]->b_data, mem, len);
175 		mem += uspi->s_fsize;
176 		size -= len;
177 		bhno++;
178 	}
179 }
180 
181 dev_t
182 ufs_get_inode_dev(struct super_block *sb, struct ufs_inode_info *ufsi)
183 {
184 	__u32 fs32;
185 	dev_t dev;
186 
187 	if ((UFS_SB(sb)->s_flags & UFS_ST_MASK) == UFS_ST_SUNx86)
188 		fs32 = fs32_to_cpu(sb, ufsi->i_u1.i_data[1]);
189 	else
190 		fs32 = fs32_to_cpu(sb, ufsi->i_u1.i_data[0]);
191 	switch (UFS_SB(sb)->s_flags & UFS_ST_MASK) {
192 	case UFS_ST_SUNx86:
193 	case UFS_ST_SUN:
194 		if ((fs32 & 0xffff0000) == 0 ||
195 		    (fs32 & 0xffff0000) == 0xffff0000)
196 			dev = old_decode_dev(fs32 & 0x7fff);
197 		else
198 			dev = MKDEV(sysv_major(fs32), sysv_minor(fs32));
199 		break;
200 
201 	default:
202 		dev = old_decode_dev(fs32);
203 		break;
204 	}
205 	return dev;
206 }
207 
208 void
209 ufs_set_inode_dev(struct super_block *sb, struct ufs_inode_info *ufsi, dev_t dev)
210 {
211 	__u32 fs32;
212 
213 	switch (UFS_SB(sb)->s_flags & UFS_ST_MASK) {
214 	case UFS_ST_SUNx86:
215 	case UFS_ST_SUN:
216 		fs32 = sysv_encode_dev(dev);
217 		if ((fs32 & 0xffff8000) == 0) {
218 			fs32 = old_encode_dev(dev);
219 		}
220 		break;
221 
222 	default:
223 		fs32 = old_encode_dev(dev);
224 		break;
225 	}
226 	if ((UFS_SB(sb)->s_flags & UFS_ST_MASK) == UFS_ST_SUNx86)
227 		ufsi->i_u1.i_data[1] = cpu_to_fs32(sb, fs32);
228 	else
229 		ufsi->i_u1.i_data[0] = cpu_to_fs32(sb, fs32);
230 }
231 
232 /**
233  * ufs_get_locked_page() - locate, pin and lock a pagecache page, if not exist
234  * read it from disk.
235  * @mapping: the address_space to search
236  * @index: the page index
237  *
238  * Locates the desired pagecache page, if not exist we'll read it,
239  * locks it, increments its reference
240  * count and returns its address.
241  *
242  */
243 
244 struct page *ufs_get_locked_page(struct address_space *mapping,
245 				 pgoff_t index)
246 {
247 	struct page *page;
248 
249 	page = find_lock_page(mapping, index);
250 	if (!page) {
251 		page = read_mapping_page(mapping, index, NULL);
252 
253 		if (IS_ERR(page)) {
254 			printk(KERN_ERR "ufs_change_blocknr: "
255 			       "read_mapping_page error: ino %lu, index: %lu\n",
256 			       mapping->host->i_ino, index);
257 			goto out;
258 		}
259 
260 		lock_page(page);
261 
262 		if (unlikely(page->mapping == NULL)) {
263 			/* Truncate got there first */
264 			unlock_page(page);
265 			page_cache_release(page);
266 			page = NULL;
267 			goto out;
268 		}
269 
270 		if (!PageUptodate(page) || PageError(page)) {
271 			unlock_page(page);
272 			page_cache_release(page);
273 
274 			printk(KERN_ERR "ufs_change_blocknr: "
275 			       "can not read page: ino %lu, index: %lu\n",
276 			       mapping->host->i_ino, index);
277 
278 			page = ERR_PTR(-EIO);
279 		}
280 	}
281 out:
282 	return page;
283 }
284