xref: /openbmc/linux/drivers/tty/vt/consolemap.c (revision 447e9a7c668113e85e2b6a7a330a3b517cae6c93)
1 // SPDX-License-Identifier: GPL-2.0
2 /*
3  * consolemap.c
4  *
5  * Mapping from internal code (such as Latin-1 or Unicode or IBM PC code)
6  * to font positions.
7  *
8  * aeb, 950210
9  *
10  * Support for multiple unimaps by Jakub Jelinek <jj@ultra.linux.cz>, July 1998
11  *
12  * Fix bug in inverse translation. Stanislav Voronyi <stas@cnti.uanet.kharkov.ua>, Dec 1998
13  *
14  * In order to prevent the following circular lock dependency:
15  *   &mm->mmap_lock --> cpu_hotplug.lock --> console_lock --> &mm->mmap_lock
16  *
17  * We cannot allow page fault to happen while holding the console_lock.
18  * Therefore, all the userspace copy operations have to be done outside
19  * the console_lock critical sections.
20  *
21  * As all the affected functions are all called directly from vt_ioctl(), we
22  * can allocate some small buffers directly on stack without worrying about
23  * stack overflow.
24  */
25 
26 #include <linux/module.h>
27 #include <linux/kd.h>
28 #include <linux/errno.h>
29 #include <linux/mm.h>
30 #include <linux/slab.h>
31 #include <linux/init.h>
32 #include <linux/tty.h>
33 #include <linux/uaccess.h>
34 #include <linux/console.h>
35 #include <linux/consolemap.h>
36 #include <linux/vt_kern.h>
37 #include <linux/string.h>
38 
39 static unsigned short translations[][256] = {
40   /* 8-bit Latin-1 mapped to Unicode -- trivial mapping */
41   [LAT1_MAP] = {
42     0x0000, 0x0001, 0x0002, 0x0003, 0x0004, 0x0005, 0x0006, 0x0007,
43     0x0008, 0x0009, 0x000a, 0x000b, 0x000c, 0x000d, 0x000e, 0x000f,
44     0x0010, 0x0011, 0x0012, 0x0013, 0x0014, 0x0015, 0x0016, 0x0017,
45     0x0018, 0x0019, 0x001a, 0x001b, 0x001c, 0x001d, 0x001e, 0x001f,
46     0x0020, 0x0021, 0x0022, 0x0023, 0x0024, 0x0025, 0x0026, 0x0027,
47     0x0028, 0x0029, 0x002a, 0x002b, 0x002c, 0x002d, 0x002e, 0x002f,
48     0x0030, 0x0031, 0x0032, 0x0033, 0x0034, 0x0035, 0x0036, 0x0037,
49     0x0038, 0x0039, 0x003a, 0x003b, 0x003c, 0x003d, 0x003e, 0x003f,
50     0x0040, 0x0041, 0x0042, 0x0043, 0x0044, 0x0045, 0x0046, 0x0047,
51     0x0048, 0x0049, 0x004a, 0x004b, 0x004c, 0x004d, 0x004e, 0x004f,
52     0x0050, 0x0051, 0x0052, 0x0053, 0x0054, 0x0055, 0x0056, 0x0057,
53     0x0058, 0x0059, 0x005a, 0x005b, 0x005c, 0x005d, 0x005e, 0x005f,
54     0x0060, 0x0061, 0x0062, 0x0063, 0x0064, 0x0065, 0x0066, 0x0067,
55     0x0068, 0x0069, 0x006a, 0x006b, 0x006c, 0x006d, 0x006e, 0x006f,
56     0x0070, 0x0071, 0x0072, 0x0073, 0x0074, 0x0075, 0x0076, 0x0077,
57     0x0078, 0x0079, 0x007a, 0x007b, 0x007c, 0x007d, 0x007e, 0x007f,
58     0x0080, 0x0081, 0x0082, 0x0083, 0x0084, 0x0085, 0x0086, 0x0087,
59     0x0088, 0x0089, 0x008a, 0x008b, 0x008c, 0x008d, 0x008e, 0x008f,
60     0x0090, 0x0091, 0x0092, 0x0093, 0x0094, 0x0095, 0x0096, 0x0097,
61     0x0098, 0x0099, 0x009a, 0x009b, 0x009c, 0x009d, 0x009e, 0x009f,
62     0x00a0, 0x00a1, 0x00a2, 0x00a3, 0x00a4, 0x00a5, 0x00a6, 0x00a7,
63     0x00a8, 0x00a9, 0x00aa, 0x00ab, 0x00ac, 0x00ad, 0x00ae, 0x00af,
64     0x00b0, 0x00b1, 0x00b2, 0x00b3, 0x00b4, 0x00b5, 0x00b6, 0x00b7,
65     0x00b8, 0x00b9, 0x00ba, 0x00bb, 0x00bc, 0x00bd, 0x00be, 0x00bf,
66     0x00c0, 0x00c1, 0x00c2, 0x00c3, 0x00c4, 0x00c5, 0x00c6, 0x00c7,
67     0x00c8, 0x00c9, 0x00ca, 0x00cb, 0x00cc, 0x00cd, 0x00ce, 0x00cf,
68     0x00d0, 0x00d1, 0x00d2, 0x00d3, 0x00d4, 0x00d5, 0x00d6, 0x00d7,
69     0x00d8, 0x00d9, 0x00da, 0x00db, 0x00dc, 0x00dd, 0x00de, 0x00df,
70     0x00e0, 0x00e1, 0x00e2, 0x00e3, 0x00e4, 0x00e5, 0x00e6, 0x00e7,
71     0x00e8, 0x00e9, 0x00ea, 0x00eb, 0x00ec, 0x00ed, 0x00ee, 0x00ef,
72     0x00f0, 0x00f1, 0x00f2, 0x00f3, 0x00f4, 0x00f5, 0x00f6, 0x00f7,
73     0x00f8, 0x00f9, 0x00fa, 0x00fb, 0x00fc, 0x00fd, 0x00fe, 0x00ff
74   },
75   /* VT100 graphics mapped to Unicode */
76   [GRAF_MAP] = {
77     0x0000, 0x0001, 0x0002, 0x0003, 0x0004, 0x0005, 0x0006, 0x0007,
78     0x0008, 0x0009, 0x000a, 0x000b, 0x000c, 0x000d, 0x000e, 0x000f,
79     0x0010, 0x0011, 0x0012, 0x0013, 0x0014, 0x0015, 0x0016, 0x0017,
80     0x0018, 0x0019, 0x001a, 0x001b, 0x001c, 0x001d, 0x001e, 0x001f,
81     0x0020, 0x0021, 0x0022, 0x0023, 0x0024, 0x0025, 0x0026, 0x0027,
82     0x0028, 0x0029, 0x002a, 0x2192, 0x2190, 0x2191, 0x2193, 0x002f,
83     0x2588, 0x0031, 0x0032, 0x0033, 0x0034, 0x0035, 0x0036, 0x0037,
84     0x0038, 0x0039, 0x003a, 0x003b, 0x003c, 0x003d, 0x003e, 0x003f,
85     0x0040, 0x0041, 0x0042, 0x0043, 0x0044, 0x0045, 0x0046, 0x0047,
86     0x0048, 0x0049, 0x004a, 0x004b, 0x004c, 0x004d, 0x004e, 0x004f,
87     0x0050, 0x0051, 0x0052, 0x0053, 0x0054, 0x0055, 0x0056, 0x0057,
88     0x0058, 0x0059, 0x005a, 0x005b, 0x005c, 0x005d, 0x005e, 0x00a0,
89     0x25c6, 0x2592, 0x2409, 0x240c, 0x240d, 0x240a, 0x00b0, 0x00b1,
90     0x2591, 0x240b, 0x2518, 0x2510, 0x250c, 0x2514, 0x253c, 0x23ba,
91     0x23bb, 0x2500, 0x23bc, 0x23bd, 0x251c, 0x2524, 0x2534, 0x252c,
92     0x2502, 0x2264, 0x2265, 0x03c0, 0x2260, 0x00a3, 0x00b7, 0x007f,
93     0x0080, 0x0081, 0x0082, 0x0083, 0x0084, 0x0085, 0x0086, 0x0087,
94     0x0088, 0x0089, 0x008a, 0x008b, 0x008c, 0x008d, 0x008e, 0x008f,
95     0x0090, 0x0091, 0x0092, 0x0093, 0x0094, 0x0095, 0x0096, 0x0097,
96     0x0098, 0x0099, 0x009a, 0x009b, 0x009c, 0x009d, 0x009e, 0x009f,
97     0x00a0, 0x00a1, 0x00a2, 0x00a3, 0x00a4, 0x00a5, 0x00a6, 0x00a7,
98     0x00a8, 0x00a9, 0x00aa, 0x00ab, 0x00ac, 0x00ad, 0x00ae, 0x00af,
99     0x00b0, 0x00b1, 0x00b2, 0x00b3, 0x00b4, 0x00b5, 0x00b6, 0x00b7,
100     0x00b8, 0x00b9, 0x00ba, 0x00bb, 0x00bc, 0x00bd, 0x00be, 0x00bf,
101     0x00c0, 0x00c1, 0x00c2, 0x00c3, 0x00c4, 0x00c5, 0x00c6, 0x00c7,
102     0x00c8, 0x00c9, 0x00ca, 0x00cb, 0x00cc, 0x00cd, 0x00ce, 0x00cf,
103     0x00d0, 0x00d1, 0x00d2, 0x00d3, 0x00d4, 0x00d5, 0x00d6, 0x00d7,
104     0x00d8, 0x00d9, 0x00da, 0x00db, 0x00dc, 0x00dd, 0x00de, 0x00df,
105     0x00e0, 0x00e1, 0x00e2, 0x00e3, 0x00e4, 0x00e5, 0x00e6, 0x00e7,
106     0x00e8, 0x00e9, 0x00ea, 0x00eb, 0x00ec, 0x00ed, 0x00ee, 0x00ef,
107     0x00f0, 0x00f1, 0x00f2, 0x00f3, 0x00f4, 0x00f5, 0x00f6, 0x00f7,
108     0x00f8, 0x00f9, 0x00fa, 0x00fb, 0x00fc, 0x00fd, 0x00fe, 0x00ff
109   },
110   /* IBM Codepage 437 mapped to Unicode */
111   [IBMPC_MAP] = {
112     0x0000, 0x263a, 0x263b, 0x2665, 0x2666, 0x2663, 0x2660, 0x2022,
113     0x25d8, 0x25cb, 0x25d9, 0x2642, 0x2640, 0x266a, 0x266b, 0x263c,
114     0x25b6, 0x25c0, 0x2195, 0x203c, 0x00b6, 0x00a7, 0x25ac, 0x21a8,
115     0x2191, 0x2193, 0x2192, 0x2190, 0x221f, 0x2194, 0x25b2, 0x25bc,
116     0x0020, 0x0021, 0x0022, 0x0023, 0x0024, 0x0025, 0x0026, 0x0027,
117     0x0028, 0x0029, 0x002a, 0x002b, 0x002c, 0x002d, 0x002e, 0x002f,
118     0x0030, 0x0031, 0x0032, 0x0033, 0x0034, 0x0035, 0x0036, 0x0037,
119     0x0038, 0x0039, 0x003a, 0x003b, 0x003c, 0x003d, 0x003e, 0x003f,
120     0x0040, 0x0041, 0x0042, 0x0043, 0x0044, 0x0045, 0x0046, 0x0047,
121     0x0048, 0x0049, 0x004a, 0x004b, 0x004c, 0x004d, 0x004e, 0x004f,
122     0x0050, 0x0051, 0x0052, 0x0053, 0x0054, 0x0055, 0x0056, 0x0057,
123     0x0058, 0x0059, 0x005a, 0x005b, 0x005c, 0x005d, 0x005e, 0x005f,
124     0x0060, 0x0061, 0x0062, 0x0063, 0x0064, 0x0065, 0x0066, 0x0067,
125     0x0068, 0x0069, 0x006a, 0x006b, 0x006c, 0x006d, 0x006e, 0x006f,
126     0x0070, 0x0071, 0x0072, 0x0073, 0x0074, 0x0075, 0x0076, 0x0077,
127     0x0078, 0x0079, 0x007a, 0x007b, 0x007c, 0x007d, 0x007e, 0x2302,
128     0x00c7, 0x00fc, 0x00e9, 0x00e2, 0x00e4, 0x00e0, 0x00e5, 0x00e7,
129     0x00ea, 0x00eb, 0x00e8, 0x00ef, 0x00ee, 0x00ec, 0x00c4, 0x00c5,
130     0x00c9, 0x00e6, 0x00c6, 0x00f4, 0x00f6, 0x00f2, 0x00fb, 0x00f9,
131     0x00ff, 0x00d6, 0x00dc, 0x00a2, 0x00a3, 0x00a5, 0x20a7, 0x0192,
132     0x00e1, 0x00ed, 0x00f3, 0x00fa, 0x00f1, 0x00d1, 0x00aa, 0x00ba,
133     0x00bf, 0x2310, 0x00ac, 0x00bd, 0x00bc, 0x00a1, 0x00ab, 0x00bb,
134     0x2591, 0x2592, 0x2593, 0x2502, 0x2524, 0x2561, 0x2562, 0x2556,
135     0x2555, 0x2563, 0x2551, 0x2557, 0x255d, 0x255c, 0x255b, 0x2510,
136     0x2514, 0x2534, 0x252c, 0x251c, 0x2500, 0x253c, 0x255e, 0x255f,
137     0x255a, 0x2554, 0x2569, 0x2566, 0x2560, 0x2550, 0x256c, 0x2567,
138     0x2568, 0x2564, 0x2565, 0x2559, 0x2558, 0x2552, 0x2553, 0x256b,
139     0x256a, 0x2518, 0x250c, 0x2588, 0x2584, 0x258c, 0x2590, 0x2580,
140     0x03b1, 0x00df, 0x0393, 0x03c0, 0x03a3, 0x03c3, 0x00b5, 0x03c4,
141     0x03a6, 0x0398, 0x03a9, 0x03b4, 0x221e, 0x03c6, 0x03b5, 0x2229,
142     0x2261, 0x00b1, 0x2265, 0x2264, 0x2320, 0x2321, 0x00f7, 0x2248,
143     0x00b0, 0x2219, 0x00b7, 0x221a, 0x207f, 0x00b2, 0x25a0, 0x00a0
144   },
145   /* User mapping -- default to codes for direct font mapping */
146   [USER_MAP] = {
147     0xf000, 0xf001, 0xf002, 0xf003, 0xf004, 0xf005, 0xf006, 0xf007,
148     0xf008, 0xf009, 0xf00a, 0xf00b, 0xf00c, 0xf00d, 0xf00e, 0xf00f,
149     0xf010, 0xf011, 0xf012, 0xf013, 0xf014, 0xf015, 0xf016, 0xf017,
150     0xf018, 0xf019, 0xf01a, 0xf01b, 0xf01c, 0xf01d, 0xf01e, 0xf01f,
151     0xf020, 0xf021, 0xf022, 0xf023, 0xf024, 0xf025, 0xf026, 0xf027,
152     0xf028, 0xf029, 0xf02a, 0xf02b, 0xf02c, 0xf02d, 0xf02e, 0xf02f,
153     0xf030, 0xf031, 0xf032, 0xf033, 0xf034, 0xf035, 0xf036, 0xf037,
154     0xf038, 0xf039, 0xf03a, 0xf03b, 0xf03c, 0xf03d, 0xf03e, 0xf03f,
155     0xf040, 0xf041, 0xf042, 0xf043, 0xf044, 0xf045, 0xf046, 0xf047,
156     0xf048, 0xf049, 0xf04a, 0xf04b, 0xf04c, 0xf04d, 0xf04e, 0xf04f,
157     0xf050, 0xf051, 0xf052, 0xf053, 0xf054, 0xf055, 0xf056, 0xf057,
158     0xf058, 0xf059, 0xf05a, 0xf05b, 0xf05c, 0xf05d, 0xf05e, 0xf05f,
159     0xf060, 0xf061, 0xf062, 0xf063, 0xf064, 0xf065, 0xf066, 0xf067,
160     0xf068, 0xf069, 0xf06a, 0xf06b, 0xf06c, 0xf06d, 0xf06e, 0xf06f,
161     0xf070, 0xf071, 0xf072, 0xf073, 0xf074, 0xf075, 0xf076, 0xf077,
162     0xf078, 0xf079, 0xf07a, 0xf07b, 0xf07c, 0xf07d, 0xf07e, 0xf07f,
163     0xf080, 0xf081, 0xf082, 0xf083, 0xf084, 0xf085, 0xf086, 0xf087,
164     0xf088, 0xf089, 0xf08a, 0xf08b, 0xf08c, 0xf08d, 0xf08e, 0xf08f,
165     0xf090, 0xf091, 0xf092, 0xf093, 0xf094, 0xf095, 0xf096, 0xf097,
166     0xf098, 0xf099, 0xf09a, 0xf09b, 0xf09c, 0xf09d, 0xf09e, 0xf09f,
167     0xf0a0, 0xf0a1, 0xf0a2, 0xf0a3, 0xf0a4, 0xf0a5, 0xf0a6, 0xf0a7,
168     0xf0a8, 0xf0a9, 0xf0aa, 0xf0ab, 0xf0ac, 0xf0ad, 0xf0ae, 0xf0af,
169     0xf0b0, 0xf0b1, 0xf0b2, 0xf0b3, 0xf0b4, 0xf0b5, 0xf0b6, 0xf0b7,
170     0xf0b8, 0xf0b9, 0xf0ba, 0xf0bb, 0xf0bc, 0xf0bd, 0xf0be, 0xf0bf,
171     0xf0c0, 0xf0c1, 0xf0c2, 0xf0c3, 0xf0c4, 0xf0c5, 0xf0c6, 0xf0c7,
172     0xf0c8, 0xf0c9, 0xf0ca, 0xf0cb, 0xf0cc, 0xf0cd, 0xf0ce, 0xf0cf,
173     0xf0d0, 0xf0d1, 0xf0d2, 0xf0d3, 0xf0d4, 0xf0d5, 0xf0d6, 0xf0d7,
174     0xf0d8, 0xf0d9, 0xf0da, 0xf0db, 0xf0dc, 0xf0dd, 0xf0de, 0xf0df,
175     0xf0e0, 0xf0e1, 0xf0e2, 0xf0e3, 0xf0e4, 0xf0e5, 0xf0e6, 0xf0e7,
176     0xf0e8, 0xf0e9, 0xf0ea, 0xf0eb, 0xf0ec, 0xf0ed, 0xf0ee, 0xf0ef,
177     0xf0f0, 0xf0f1, 0xf0f2, 0xf0f3, 0xf0f4, 0xf0f5, 0xf0f6, 0xf0f7,
178     0xf0f8, 0xf0f9, 0xf0fa, 0xf0fb, 0xf0fc, 0xf0fd, 0xf0fe, 0xf0ff
179   }
180 };
181 
182 /* The standard kernel character-to-font mappings are not invertible
183    -- this is just a best effort. */
184 
185 #define MAX_GLYPH 512		/* Max possible glyph value */
186 
187 static enum translation_map inv_translate[MAX_NR_CONSOLES];
188 
189 #define UNI_DIRS	32U
190 #define UNI_DIR_ROWS	32U
191 #define UNI_ROW_GLYPHS	64U
192 
193 #define UNI_DIR(uni)		( (uni)                   >> 11)
194 #define UNI_ROW(uni)		(((uni) & GENMASK(10, 6)) >>  6)
195 #define UNI_GLYPH(uni)		( (uni) & GENMASK( 5, 0))
196 #define UNI(dir, row, glyph)	(((dir) << 11) | ((row) << 6) | (glyph))
197 
198 /**
199  * struct uni_pagedict -- unicode directory
200  *
201  * @uni_pgdir: 32*32*64 table with glyphs
202  * @refcount: reference count of this structure
203  * @sum: checksum
204  * @inverse_translations: best-effort inverse mapping
205  * @inverse_trans_unicode: best-effort inverse mapping to unicode
206  */
207 struct uni_pagedict {
208 	u16		**uni_pgdir[UNI_DIRS];
209 	unsigned long	refcount;
210 	unsigned long	sum;
211 	unsigned char	*inverse_translations[LAST_MAP + 1];
212 	u16		*inverse_trans_unicode;
213 };
214 
215 static struct uni_pagedict *dflt;
216 
217 static void set_inverse_transl(struct vc_data *conp, struct uni_pagedict *p,
218 	       enum translation_map m)
219 {
220 	int j, glyph;
221 	unsigned short *t = translations[m];
222 	unsigned char *q;
223 
224 	if (!p)
225 		return;
226 	q = p->inverse_translations[m];
227 
228 	if (!q) {
229 		q = p->inverse_translations[m] = kmalloc(MAX_GLYPH, GFP_KERNEL);
230 		if (!q)
231 			return;
232 	}
233 	memset(q, 0, MAX_GLYPH);
234 
235 	for (j = 0; j < E_TABSZ; j++) {
236 		glyph = conv_uni_to_pc(conp, t[j]);
237 		if (glyph >= 0 && glyph < MAX_GLYPH && q[glyph] < 32) {
238 			/* prefer '-' above SHY etc. */
239 		  	q[glyph] = j;
240 		}
241 	}
242 }
243 
244 static void set_inverse_trans_unicode(struct vc_data *conp,
245 				      struct uni_pagedict *p)
246 {
247 	unsigned int d, r, g;
248 	u16 *inv;
249 
250 	if (!p)
251 		return;
252 
253 	inv = p->inverse_trans_unicode;
254 	if (!inv) {
255 		inv = p->inverse_trans_unicode = kmalloc_array(MAX_GLYPH,
256 				sizeof(*inv), GFP_KERNEL);
257 		if (!inv)
258 			return;
259 	}
260 	memset(inv, 0, MAX_GLYPH * sizeof(*inv));
261 
262 	for (d = 0; d < UNI_DIRS; d++) {
263 		u16 **dir = p->uni_pgdir[d];
264 		if (!dir)
265 			continue;
266 		for (r = 0; r < UNI_DIR_ROWS; r++) {
267 			u16 *row = dir[r];
268 			if (!row)
269 				continue;
270 			for (g = 0; g < UNI_ROW_GLYPHS; g++) {
271 				u16 glyph = row[g];
272 				if (glyph < MAX_GLYPH && inv[glyph] < 32)
273 					inv[glyph] = UNI(d, r, g);
274 			}
275 		}
276 	}
277 }
278 
279 unsigned short *set_translate(enum translation_map m, struct vc_data *vc)
280 {
281 	inv_translate[vc->vc_num] = m;
282 	return translations[m];
283 }
284 
285 /*
286  * Inverse translation is impossible for several reasons:
287  * 1. The font<->character maps are not 1-1.
288  * 2. The text may have been written while a different translation map
289  *    was active.
290  * Still, it is now possible to a certain extent to cut and paste non-ASCII.
291  */
292 u16 inverse_translate(const struct vc_data *conp, u16 glyph, bool use_unicode)
293 {
294 	struct uni_pagedict *p;
295 	enum translation_map m;
296 
297 	if (glyph >= MAX_GLYPH)
298 		return 0;
299 
300 	p = *conp->vc_uni_pagedir_loc;
301 	if (!p)
302 		return glyph;
303 
304 	if (use_unicode) {
305 		if (!p->inverse_trans_unicode)
306 			return glyph;
307 
308 		return p->inverse_trans_unicode[glyph];
309 	}
310 
311 	m = inv_translate[conp->vc_num];
312 	if (!p->inverse_translations[m])
313 		return glyph;
314 
315 	return p->inverse_translations[m][glyph];
316 }
317 EXPORT_SYMBOL_GPL(inverse_translate);
318 
319 static void update_user_maps(void)
320 {
321 	int i;
322 	struct uni_pagedict *p, *q = NULL;
323 
324 	for (i = 0; i < MAX_NR_CONSOLES; i++) {
325 		if (!vc_cons_allocated(i))
326 			continue;
327 		p = *vc_cons[i].d->vc_uni_pagedir_loc;
328 		if (p && p != q) {
329 			set_inverse_transl(vc_cons[i].d, p, USER_MAP);
330 			set_inverse_trans_unicode(vc_cons[i].d, p);
331 			q = p;
332 		}
333 	}
334 }
335 
336 /*
337  * Load customizable translation table
338  * arg points to a 256 byte translation table.
339  *
340  * The "old" variants are for translation directly to font (using the
341  * 0xf000-0xf0ff "transparent" Unicodes) whereas the "new" variants set
342  * Unicodes explicitly.
343  */
344 int con_set_trans_old(unsigned char __user * arg)
345 {
346 	int i;
347 	unsigned short inbuf[E_TABSZ];
348 	unsigned char ubuf[E_TABSZ];
349 
350 	if (copy_from_user(ubuf, arg, E_TABSZ))
351 		return -EFAULT;
352 
353 	for (i = 0; i < E_TABSZ ; i++)
354 		inbuf[i] = UNI_DIRECT_BASE | ubuf[i];
355 
356 	console_lock();
357 	memcpy(translations[USER_MAP], inbuf, sizeof(inbuf));
358 	update_user_maps();
359 	console_unlock();
360 	return 0;
361 }
362 
363 int con_get_trans_old(unsigned char __user * arg)
364 {
365 	int i, ch;
366 	unsigned short *p = translations[USER_MAP];
367 	unsigned char outbuf[E_TABSZ];
368 
369 	console_lock();
370 	for (i = 0; i < E_TABSZ ; i++)
371 	{
372 		ch = conv_uni_to_pc(vc_cons[fg_console].d, p[i]);
373 		outbuf[i] = (ch & ~0xff) ? 0 : ch;
374 	}
375 	console_unlock();
376 
377 	return copy_to_user(arg, outbuf, sizeof(outbuf)) ? -EFAULT : 0;
378 }
379 
380 int con_set_trans_new(ushort __user * arg)
381 {
382 	unsigned short inbuf[E_TABSZ];
383 
384 	if (copy_from_user(inbuf, arg, sizeof(inbuf)))
385 		return -EFAULT;
386 
387 	console_lock();
388 	memcpy(translations[USER_MAP], inbuf, sizeof(inbuf));
389 	update_user_maps();
390 	console_unlock();
391 	return 0;
392 }
393 
394 int con_get_trans_new(ushort __user * arg)
395 {
396 	unsigned short outbuf[E_TABSZ];
397 
398 	console_lock();
399 	memcpy(outbuf, translations[USER_MAP], sizeof(outbuf));
400 	console_unlock();
401 
402 	return copy_to_user(arg, outbuf, sizeof(outbuf)) ? -EFAULT : 0;
403 }
404 
405 /*
406  * Unicode -> current font conversion
407  *
408  * A font has at most 512 chars, usually 256.
409  * But one font position may represent several Unicode chars.
410  * A hashtable is somewhat of a pain to deal with, so use a
411  * "paged table" instead.  Simulation has shown the memory cost of
412  * this 3-level paged table scheme to be comparable to a hash table.
413  */
414 
415 extern u8 dfont_unicount[];	/* Defined in console_defmap.c */
416 extern u16 dfont_unitable[];
417 
418 static void con_release_unimap(struct uni_pagedict *dict)
419 {
420 	unsigned int d, r;
421 
422 	if (dict == dflt)
423 		dflt = NULL;
424 
425 	for (d = 0; d < UNI_DIRS; d++) {
426 		u16 **dir = dict->uni_pgdir[d];
427 		if (dir != NULL) {
428 			for (r = 0; r < UNI_DIR_ROWS; r++)
429 				kfree(dir[r]);
430 			kfree(dir);
431 		}
432 		dict->uni_pgdir[d] = NULL;
433 	}
434 
435 	for (r = 0; r < ARRAY_SIZE(dict->inverse_translations); r++) {
436 		kfree(dict->inverse_translations[r]);
437 		dict->inverse_translations[r] = NULL;
438 	}
439 
440 	kfree(dict->inverse_trans_unicode);
441 	dict->inverse_trans_unicode = NULL;
442 }
443 
444 /* Caller must hold the console lock */
445 void con_free_unimap(struct vc_data *vc)
446 {
447 	struct uni_pagedict *p;
448 
449 	p = *vc->vc_uni_pagedir_loc;
450 	if (!p)
451 		return;
452 	*vc->vc_uni_pagedir_loc = NULL;
453 	if (--p->refcount)
454 		return;
455 	con_release_unimap(p);
456 	kfree(p);
457 }
458 
459 static int con_unify_unimap(struct vc_data *conp, struct uni_pagedict *dict1)
460 {
461 	struct uni_pagedict *dict2;
462 	unsigned int cons, d, r;
463 
464 	for (cons = 0; cons < MAX_NR_CONSOLES; cons++) {
465 		if (!vc_cons_allocated(cons))
466 			continue;
467 		dict2 = *vc_cons[cons].d->vc_uni_pagedir_loc;
468 		if (!dict2 || dict2 == dict1 || dict2->sum != dict1->sum)
469 			continue;
470 		for (d = 0; d < UNI_DIRS; d++) {
471 			u16 **dir1 = dict1->uni_pgdir[d];
472 			u16 **dir2 = dict2->uni_pgdir[d];
473 			if (!dir1 && !dir2)
474 				continue;
475 			if (!dir1 || !dir2)
476 				break;
477 			for (r = 0; r < UNI_DIR_ROWS; r++) {
478 				if (!dir1[r] && !dir2[r])
479 					continue;
480 				if (!dir1[r] || !dir2[r])
481 					break;
482 				if (memcmp(dir1[r], dir2[r], UNI_ROW_GLYPHS *
483 							sizeof(*dir1[r])))
484 					break;
485 			}
486 			if (r < UNI_DIR_ROWS)
487 				break;
488 		}
489 		if (d == UNI_DIRS) {
490 			dict2->refcount++;
491 			*conp->vc_uni_pagedir_loc = dict2;
492 			con_release_unimap(dict1);
493 			kfree(dict1);
494 			return 1;
495 		}
496 	}
497 	return 0;
498 }
499 
500 static int
501 con_insert_unipair(struct uni_pagedict *p, u_short unicode, u_short fontpos)
502 {
503 	u16 **dir, *row;
504 	unsigned int n;
505 
506 	n = UNI_DIR(unicode);
507 	dir = p->uni_pgdir[n];
508 	if (!dir) {
509 		dir = p->uni_pgdir[n] = kcalloc(UNI_DIR_ROWS, sizeof(*dir),
510 				GFP_KERNEL);
511 		if (!dir)
512 			return -ENOMEM;
513 	}
514 
515 	n = UNI_ROW(unicode);
516 	row = dir[n];
517 	if (!row) {
518 		row = dir[n] = kmalloc_array(UNI_ROW_GLYPHS, sizeof(*row),
519 				GFP_KERNEL);
520 		if (!row)
521 			return -ENOMEM;
522 		/* No glyphs for the characters (yet) */
523 		memset(row, 0xff, UNI_ROW_GLYPHS * sizeof(*row));
524 	}
525 
526 	row[UNI_GLYPH(unicode)] = fontpos;
527 
528 	p->sum += (fontpos << 20U) + unicode;
529 
530 	return 0;
531 }
532 
533 /* Caller must hold the lock */
534 static int con_do_clear_unimap(struct vc_data *vc)
535 {
536 	struct uni_pagedict *old = *vc->vc_uni_pagedir_loc;
537 
538 	if (!old || --old->refcount) {
539 		struct uni_pagedict *new = kzalloc(sizeof(*new), GFP_KERNEL);
540 		if (!new) {
541 			if (old)
542 				old->refcount++;
543 			return -ENOMEM;
544 		}
545 		new->refcount = 1;
546 		*vc->vc_uni_pagedir_loc = new;
547 	} else {
548 		if (old == dflt)
549 			dflt = NULL;
550 		old->refcount++;
551 		old->sum = 0;
552 		con_release_unimap(old);
553 	}
554 	return 0;
555 }
556 
557 int con_clear_unimap(struct vc_data *vc)
558 {
559 	int ret;
560 	console_lock();
561 	ret = con_do_clear_unimap(vc);
562 	console_unlock();
563 	return ret;
564 }
565 
566 static struct uni_pagedict *con_unshare_unimap(struct vc_data *vc,
567 		struct uni_pagedict *old)
568 {
569 	struct uni_pagedict *new;
570 	unsigned int d, r, g;
571 	int ret;
572 	u16 uni = 0;
573 
574 	ret = con_do_clear_unimap(vc);
575 	if (ret)
576 		return ERR_PTR(ret);
577 
578 	/*
579 	 * Since refcount was > 1, con_clear_unimap() allocated a new
580 	 * uni_pagedict for this vc.  Re: old != new
581 	 */
582 	new = *vc->vc_uni_pagedir_loc;
583 
584 	/*
585 	 * uni_pgdir is a 32*32*64 table with rows allocated when its first
586 	 * entry is added. The unicode value must still be incremented for
587 	 * empty rows. We are copying entries from "old" to "new".
588 	 */
589 	for (d = 0; d < UNI_DIRS; d++) {
590 		u16 **dir = old->uni_pgdir[d];
591 		if (!dir) {
592 			/* Account for empty table */
593 			uni += UNI_DIR_ROWS * UNI_ROW_GLYPHS;
594 			continue;
595 		}
596 
597 		for (r = 0; r < UNI_DIR_ROWS; r++) {
598 			u16 *row = dir[r];
599 			if (!row) {
600 				/* Account for row of 64 empty entries */
601 				uni += UNI_ROW_GLYPHS;
602 				continue;
603 			}
604 
605 			for (g = 0; g < UNI_ROW_GLYPHS; g++, uni++) {
606 				if (row[g] == 0xffff)
607 					continue;
608 				/*
609 				 * Found one, copy entry for unicode uni with
610 				 * fontpos value row[g].
611 				 */
612 				ret = con_insert_unipair(new, uni, row[g]);
613 				if (ret) {
614 					old->refcount++;
615 					*vc->vc_uni_pagedir_loc = old;
616 					con_release_unimap(new);
617 					kfree(new);
618 					return ERR_PTR(ret);
619 				}
620 			}
621 		}
622 	}
623 
624 	return new;
625 }
626 
627 int con_set_unimap(struct vc_data *vc, ushort ct, struct unipair __user *list)
628 {
629 	int err = 0, err1;
630 	struct uni_pagedict *p;
631 	struct unipair *unilist, *plist;
632 
633 	if (!ct)
634 		return 0;
635 
636 	unilist = vmemdup_user(list, array_size(sizeof(*unilist), ct));
637 	if (IS_ERR(unilist))
638 		return PTR_ERR(unilist);
639 
640 	console_lock();
641 
642 	/* Save original vc_unipagdir_loc in case we allocate a new one */
643 	p = *vc->vc_uni_pagedir_loc;
644 	if (!p) {
645 		err = -EINVAL;
646 		goto out_unlock;
647 	}
648 
649 	if (p->refcount > 1) {
650 		p = con_unshare_unimap(vc, p);
651 		if (IS_ERR(p)) {
652 			err = PTR_ERR(p);
653 			goto out_unlock;
654 		}
655 	} else if (p == dflt) {
656 		dflt = NULL;
657 	}
658 
659 	/*
660 	 * Insert user specified unicode pairs into new table.
661 	 */
662 	for (plist = unilist; ct; ct--, plist++) {
663 		err1 = con_insert_unipair(p, plist->unicode, plist->fontpos);
664 		if (err1)
665 			err = err1;
666 	}
667 
668 	/*
669 	 * Merge with fontmaps of any other virtual consoles.
670 	 */
671 	if (con_unify_unimap(vc, p))
672 		goto out_unlock;
673 
674 	for (enum translation_map m = FIRST_MAP; m <= LAST_MAP; m++)
675 		set_inverse_transl(vc, p, m); /* Update inverse translations */
676 	set_inverse_trans_unicode(vc, p);
677 
678 out_unlock:
679 	console_unlock();
680 	kvfree(unilist);
681 	return err;
682 }
683 
684 /**
685  *	con_set_default_unimap	-	set default unicode map
686  *	@vc: the console we are updating
687  *
688  *	Loads the unimap for the hardware font, as defined in uni_hash.tbl.
689  *	The representation used was the most compact I could come up
690  *	with.  This routine is executed at video setup, and when the
691  *	PIO_FONTRESET ioctl is called.
692  *
693  *	The caller must hold the console lock
694  */
695 int con_set_default_unimap(struct vc_data *vc)
696 {
697 	int i, j, err = 0, err1;
698 	u16 *q;
699 	struct uni_pagedict *p;
700 
701 	if (dflt) {
702 		p = *vc->vc_uni_pagedir_loc;
703 		if (p == dflt)
704 			return 0;
705 
706 		dflt->refcount++;
707 		*vc->vc_uni_pagedir_loc = dflt;
708 		if (p && !--p->refcount) {
709 			con_release_unimap(p);
710 			kfree(p);
711 		}
712 		return 0;
713 	}
714 
715 	/* The default font is always 256 characters */
716 
717 	err = con_do_clear_unimap(vc);
718 	if (err)
719 		return err;
720 
721 	p = *vc->vc_uni_pagedir_loc;
722 	q = dfont_unitable;
723 
724 	for (i = 0; i < 256; i++)
725 		for (j = dfont_unicount[i]; j; j--) {
726 			err1 = con_insert_unipair(p, *(q++), i);
727 			if (err1)
728 				err = err1;
729 		}
730 
731 	if (con_unify_unimap(vc, p)) {
732 		dflt = *vc->vc_uni_pagedir_loc;
733 		return err;
734 	}
735 
736 	for (enum translation_map m = FIRST_MAP; m <= LAST_MAP; m++)
737 		set_inverse_transl(vc, p, m);	/* Update all inverse translations */
738 	set_inverse_trans_unicode(vc, p);
739 	dflt = p;
740 	return err;
741 }
742 EXPORT_SYMBOL(con_set_default_unimap);
743 
744 /**
745  *	con_copy_unimap		-	copy unimap between two vts
746  *	@dst_vc: target
747  *	@src_vc: source
748  *
749  *	The caller must hold the console lock when invoking this method
750  */
751 int con_copy_unimap(struct vc_data *dst_vc, struct vc_data *src_vc)
752 {
753 	struct uni_pagedict *q;
754 
755 	if (!*src_vc->vc_uni_pagedir_loc)
756 		return -EINVAL;
757 	if (*dst_vc->vc_uni_pagedir_loc == *src_vc->vc_uni_pagedir_loc)
758 		return 0;
759 	con_free_unimap(dst_vc);
760 	q = *src_vc->vc_uni_pagedir_loc;
761 	q->refcount++;
762 	*dst_vc->vc_uni_pagedir_loc = q;
763 	return 0;
764 }
765 EXPORT_SYMBOL(con_copy_unimap);
766 
767 /*
768  *	con_get_unimap		-	get the unicode map
769  *
770  *	Read the console unicode data for this console. Called from the ioctl
771  *	handlers.
772  */
773 int con_get_unimap(struct vc_data *vc, ushort ct, ushort __user *uct,
774 		struct unipair __user *list)
775 {
776 	int i, j, k, ret = 0;
777 	ushort ect;
778 	u16 **p1, *p2;
779 	struct uni_pagedict *p;
780 	struct unipair *unilist;
781 
782 	unilist = kvmalloc_array(ct, sizeof(*unilist), GFP_KERNEL);
783 	if (!unilist)
784 		return -ENOMEM;
785 
786 	console_lock();
787 
788 	ect = 0;
789 	p = *vc->vc_uni_pagedir_loc;
790 	if (!p)
791 		goto unlock;
792 
793 	for (i = 0; i < UNI_DIRS; i++) {
794 		p1 = p->uni_pgdir[i];
795 		if (!p1)
796 			continue;
797 
798 		for (j = 0; j < UNI_DIR_ROWS; j++, p1++) {
799 			p2 = *p1;
800 			if (!p2)
801 				continue;
802 
803 			for (k = 0; k < UNI_ROW_GLYPHS; k++, p2++) {
804 				if (*p2 >= MAX_GLYPH)
805 					continue;
806 				if (ect < ct) {
807 					unilist[ect].unicode = UNI(i, j, k);
808 					unilist[ect].fontpos = *p2;
809 				}
810 				ect++;
811 			}
812 		}
813 	}
814 unlock:
815 	console_unlock();
816 	if (copy_to_user(list, unilist, min(ect, ct) * sizeof(*unilist)))
817 		ret = -EFAULT;
818 	if (put_user(ect, uct))
819 		ret = -EFAULT;
820 	kvfree(unilist);
821 	return ret ? ret : (ect <= ct) ? 0 : -ENOMEM;
822 }
823 
824 /*
825  * Always use USER_MAP. These functions are used by the keyboard,
826  * which shouldn't be affected by G0/G1 switching, etc.
827  * If the user map still contains default values, i.e. the
828  * direct-to-font mapping, then assume user is using Latin1.
829  *
830  * FIXME: at some point we need to decide if we want to lock the table
831  * update element itself via the keyboard_event_lock for consistency with the
832  * keyboard driver as well as the consoles
833  */
834 /* may be called during an interrupt */
835 u32 conv_8bit_to_uni(unsigned char c)
836 {
837 	unsigned short uni = translations[USER_MAP][c];
838 	return uni == (0xf000 | c) ? c : uni;
839 }
840 
841 int conv_uni_to_8bit(u32 uni)
842 {
843 	int c;
844 	for (c = 0; c < ARRAY_SIZE(translations[USER_MAP]); c++)
845 		if (translations[USER_MAP][c] == uni ||
846 		   (translations[USER_MAP][c] == (c | 0xf000) && uni == c))
847 			return c;
848 	return -1;
849 }
850 
851 int
852 conv_uni_to_pc(struct vc_data *conp, long ucs)
853 {
854 	struct uni_pagedict *dict;
855 	u16 **dir, *row, glyph;
856 
857 	/* Only 16-bit codes supported at this time */
858 	if (ucs > 0xffff)
859 		return -4;		/* Not found */
860 	else if (ucs < 0x20)
861 		return -1;		/* Not a printable character */
862 	else if (ucs == 0xfeff || (ucs >= 0x200b && ucs <= 0x200f))
863 		return -2;			/* Zero-width space */
864 	/*
865 	 * UNI_DIRECT_BASE indicates the start of the region in the User Zone
866 	 * which always has a 1:1 mapping to the currently loaded font.  The
867 	 * UNI_DIRECT_MASK indicates the bit span of the region.
868 	 */
869 	else if ((ucs & ~UNI_DIRECT_MASK) == UNI_DIRECT_BASE)
870 		return ucs & UNI_DIRECT_MASK;
871 
872 	if (!*conp->vc_uni_pagedir_loc)
873 		return -3;
874 
875 	dict = *conp->vc_uni_pagedir_loc;
876 	if ((dir = dict->uni_pgdir[UNI_DIR(ucs)]) &&
877 	    (row = dir[UNI_ROW(ucs)]) &&
878 	    (glyph = row[UNI_GLYPH(ucs)]) < MAX_GLYPH)
879 		return glyph;
880 
881 	return -4;		/* not found */
882 }
883 
884 /*
885  * This is called at sys_setup time, after memory and the console are
886  * initialized.  It must be possible to call kmalloc(..., GFP_KERNEL)
887  * from this function, hence the call from sys_setup.
888  */
889 void __init
890 console_map_init(void)
891 {
892 	int i;
893 
894 	for (i = 0; i < MAX_NR_CONSOLES; i++)
895 		if (vc_cons_allocated(i) && !*vc_cons[i].d->vc_uni_pagedir_loc)
896 			con_set_default_unimap(vc_cons[i].d);
897 }
898 
899