xref: /linux/fs/ufs/util.c (revision 9d8a2b033db179bef9b6b5bad492f611a0fe89b7)
1 // SPDX-License-Identifier: GPL-2.0
2 /*
3  *  linux/fs/ufs/util.c
4  *
5  * Copyright (C) 1998
6  * Daniel Pirkl <daniel.pirkl@email.cz>
7  * Charles University, Faculty of Mathematics and Physics
8  */
9 
10 #include <linux/string.h>
11 #include <linux/slab.h>
12 #include <linux/buffer_head.h>
13 
14 #include "ufs_fs.h"
15 #include "ufs.h"
16 #include "swab.h"
17 #include "util.h"
18 
19 struct ufs_buffer_head * _ubh_bread_ (struct ufs_sb_private_info * uspi,
20 	struct super_block *sb, u64 fragment, u64 size)
21 {
22 	struct ufs_buffer_head * ubh;
23 	unsigned i, j ;
24 	u64  count = 0;
25 	if (size & ~uspi->s_fmask)
26 		return NULL;
27 	count = size >> uspi->s_fshift;
28 	if (count > UFS_MAXFRAG)
29 		return NULL;
30 	ubh = 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_sync_block(struct ufs_buffer_head *ubh)
103 {
104 	if (ubh) {
105 		unsigned i;
106 
107 		for (i = 0; i < ubh->count; i++)
108 			write_dirty_buffer(ubh->bh[i], 0);
109 
110 		for (i = 0; i < ubh->count; i++)
111 			wait_on_buffer(ubh->bh[i]);
112 	}
113 }
114 
115 void ubh_bforget (struct ufs_buffer_head * ubh)
116 {
117 	unsigned i;
118 	if (!ubh)
119 		return;
120 	for ( i = 0; i < ubh->count; i++ ) if ( ubh->bh[i] )
121 		bforget (ubh->bh[i]);
122 }
123 
124 int ubh_buffer_dirty (struct ufs_buffer_head * ubh)
125 {
126 	unsigned i;
127 	unsigned result = 0;
128 	if (!ubh)
129 		return 0;
130 	for ( i = 0; i < ubh->count; i++ )
131 		result |= buffer_dirty(ubh->bh[i]);
132 	return result;
133 }
134 
135 dev_t
136 ufs_get_inode_dev(struct super_block *sb, struct ufs_inode_info *ufsi)
137 {
138 	__u32 fs32;
139 	dev_t dev;
140 
141 	if ((UFS_SB(sb)->s_flags & UFS_ST_MASK) == UFS_ST_SUNx86)
142 		fs32 = fs32_to_cpu(sb, ufsi->i_u1.i_data[1]);
143 	else
144 		fs32 = fs32_to_cpu(sb, ufsi->i_u1.i_data[0]);
145 	switch (UFS_SB(sb)->s_flags & UFS_ST_MASK) {
146 	case UFS_ST_SUNx86:
147 	case UFS_ST_SUN:
148 		if ((fs32 & 0xffff0000) == 0 ||
149 		    (fs32 & 0xffff0000) == 0xffff0000)
150 			dev = old_decode_dev(fs32 & 0x7fff);
151 		else
152 			dev = MKDEV(sysv_major(fs32), sysv_minor(fs32));
153 		break;
154 
155 	default:
156 		dev = old_decode_dev(fs32);
157 		break;
158 	}
159 	return dev;
160 }
161 
162 void
163 ufs_set_inode_dev(struct super_block *sb, struct ufs_inode_info *ufsi, dev_t dev)
164 {
165 	__u32 fs32;
166 
167 	switch (UFS_SB(sb)->s_flags & UFS_ST_MASK) {
168 	case UFS_ST_SUNx86:
169 	case UFS_ST_SUN:
170 		fs32 = sysv_encode_dev(dev);
171 		if ((fs32 & 0xffff8000) == 0) {
172 			fs32 = old_encode_dev(dev);
173 		}
174 		break;
175 
176 	default:
177 		fs32 = old_encode_dev(dev);
178 		break;
179 	}
180 	if ((UFS_SB(sb)->s_flags & UFS_ST_MASK) == UFS_ST_SUNx86)
181 		ufsi->i_u1.i_data[1] = cpu_to_fs32(sb, fs32);
182 	else
183 		ufsi->i_u1.i_data[0] = cpu_to_fs32(sb, fs32);
184 }
185 
186 /**
187  * ufs_get_locked_folio() - locate, pin and lock a pagecache folio, if not exist
188  * read it from disk.
189  * @mapping: the address_space to search
190  * @index: the page index
191  *
192  * Locates the desired pagecache folio, if not exist we'll read it,
193  * locks it, increments its reference
194  * count and returns its address.
195  *
196  */
197 struct folio *ufs_get_locked_folio(struct address_space *mapping,
198 				 pgoff_t index)
199 {
200 	struct inode *inode = mapping->host;
201 	struct folio *folio = filemap_lock_folio(mapping, index);
202 	if (IS_ERR(folio)) {
203 		folio = read_mapping_folio(mapping, index, NULL);
204 
205 		if (IS_ERR(folio)) {
206 			printk(KERN_ERR "ufs_change_blocknr: read_mapping_folio error: ino %lu, index: %lu\n",
207 			       mapping->host->i_ino, index);
208 			return folio;
209 		}
210 
211 		folio_lock(folio);
212 
213 		if (unlikely(folio->mapping == NULL)) {
214 			/* Truncate got there first */
215 			folio_unlock(folio);
216 			folio_put(folio);
217 			return NULL;
218 		}
219 	}
220 	if (!folio_buffers(folio))
221 		create_empty_buffers(folio, 1 << inode->i_blkbits, 0);
222 	return folio;
223 }
224