xref: /openbmc/linux/drivers/tty/vt/consolemap.c (revision a7e50de460d7d9230dc065c9d2f1a1b1669c675c)
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 > 1) {
539 		struct uni_pagedict *new = kzalloc(sizeof(*new), GFP_KERNEL);
540 		if (!new)
541 			return -ENOMEM;
542 
543 		new->refcount = 1;
544 		*vc->vc_uni_pagedir_loc = new;
545 
546 		if (old)
547 			old->refcount--;
548 	} else {
549 		if (old == dflt)
550 			dflt = NULL;
551 		old->sum = 0;
552 		con_release_unimap(old);
553 	}
554 
555 	return 0;
556 }
557 
558 int con_clear_unimap(struct vc_data *vc)
559 {
560 	int ret;
561 	console_lock();
562 	ret = con_do_clear_unimap(vc);
563 	console_unlock();
564 	return ret;
565 }
566 
567 static struct uni_pagedict *con_unshare_unimap(struct vc_data *vc,
568 		struct uni_pagedict *old)
569 {
570 	struct uni_pagedict *new;
571 	unsigned int d, r, g;
572 	int ret;
573 	u16 uni = 0;
574 
575 	ret = con_do_clear_unimap(vc);
576 	if (ret)
577 		return ERR_PTR(ret);
578 
579 	/*
580 	 * Since refcount was > 1, con_clear_unimap() allocated a new
581 	 * uni_pagedict for this vc.  Re: old != new
582 	 */
583 	new = *vc->vc_uni_pagedir_loc;
584 
585 	/*
586 	 * uni_pgdir is a 32*32*64 table with rows allocated when its first
587 	 * entry is added. The unicode value must still be incremented for
588 	 * empty rows. We are copying entries from "old" to "new".
589 	 */
590 	for (d = 0; d < UNI_DIRS; d++) {
591 		u16 **dir = old->uni_pgdir[d];
592 		if (!dir) {
593 			/* Account for empty table */
594 			uni += UNI_DIR_ROWS * UNI_ROW_GLYPHS;
595 			continue;
596 		}
597 
598 		for (r = 0; r < UNI_DIR_ROWS; r++) {
599 			u16 *row = dir[r];
600 			if (!row) {
601 				/* Account for row of 64 empty entries */
602 				uni += UNI_ROW_GLYPHS;
603 				continue;
604 			}
605 
606 			for (g = 0; g < UNI_ROW_GLYPHS; g++, uni++) {
607 				if (row[g] == 0xffff)
608 					continue;
609 				/*
610 				 * Found one, copy entry for unicode uni with
611 				 * fontpos value row[g].
612 				 */
613 				ret = con_insert_unipair(new, uni, row[g]);
614 				if (ret) {
615 					old->refcount++;
616 					*vc->vc_uni_pagedir_loc = old;
617 					con_release_unimap(new);
618 					kfree(new);
619 					return ERR_PTR(ret);
620 				}
621 			}
622 		}
623 	}
624 
625 	return new;
626 }
627 
628 int con_set_unimap(struct vc_data *vc, ushort ct, struct unipair __user *list)
629 {
630 	int err = 0, err1;
631 	struct uni_pagedict *dict;
632 	struct unipair *unilist, *plist;
633 
634 	if (!ct)
635 		return 0;
636 
637 	unilist = vmemdup_user(list, array_size(sizeof(*unilist), ct));
638 	if (IS_ERR(unilist))
639 		return PTR_ERR(unilist);
640 
641 	console_lock();
642 
643 	/* Save original vc_unipagdir_loc in case we allocate a new one */
644 	dict = *vc->vc_uni_pagedir_loc;
645 	if (!dict) {
646 		err = -EINVAL;
647 		goto out_unlock;
648 	}
649 
650 	if (dict->refcount > 1) {
651 		dict = con_unshare_unimap(vc, dict);
652 		if (IS_ERR(dict)) {
653 			err = PTR_ERR(dict);
654 			goto out_unlock;
655 		}
656 	} else if (dict == dflt) {
657 		dflt = NULL;
658 	}
659 
660 	/*
661 	 * Insert user specified unicode pairs into new table.
662 	 */
663 	for (plist = unilist; ct; ct--, plist++) {
664 		err1 = con_insert_unipair(dict, plist->unicode, plist->fontpos);
665 		if (err1)
666 			err = err1;
667 	}
668 
669 	/*
670 	 * Merge with fontmaps of any other virtual consoles.
671 	 */
672 	if (con_unify_unimap(vc, dict))
673 		goto out_unlock;
674 
675 	for (enum translation_map m = FIRST_MAP; m <= LAST_MAP; m++)
676 		set_inverse_transl(vc, dict, m);
677 	set_inverse_trans_unicode(vc, dict);
678 
679 out_unlock:
680 	console_unlock();
681 	kvfree(unilist);
682 	return err;
683 }
684 
685 /**
686  *	con_set_default_unimap	-	set default unicode map
687  *	@vc: the console we are updating
688  *
689  *	Loads the unimap for the hardware font, as defined in uni_hash.tbl.
690  *	The representation used was the most compact I could come up
691  *	with.  This routine is executed at video setup, and when the
692  *	PIO_FONTRESET ioctl is called.
693  *
694  *	The caller must hold the console lock
695  */
696 int con_set_default_unimap(struct vc_data *vc)
697 {
698 	struct uni_pagedict *dict;
699 	unsigned int fontpos, count;
700 	int err = 0, err1;
701 	u16 *dfont;
702 
703 	if (dflt) {
704 		dict = *vc->vc_uni_pagedir_loc;
705 		if (dict == dflt)
706 			return 0;
707 
708 		dflt->refcount++;
709 		*vc->vc_uni_pagedir_loc = dflt;
710 		if (dict && !--dict->refcount) {
711 			con_release_unimap(dict);
712 			kfree(dict);
713 		}
714 		return 0;
715 	}
716 
717 	/* The default font is always 256 characters */
718 
719 	err = con_do_clear_unimap(vc);
720 	if (err)
721 		return err;
722 
723 	dict = *vc->vc_uni_pagedir_loc;
724 	dfont = dfont_unitable;
725 
726 	for (fontpos = 0; fontpos < 256U; fontpos++)
727 		for (count = dfont_unicount[fontpos]; count; count--) {
728 			err1 = con_insert_unipair(dict, *(dfont++), fontpos);
729 			if (err1)
730 				err = err1;
731 		}
732 
733 	if (con_unify_unimap(vc, dict)) {
734 		dflt = *vc->vc_uni_pagedir_loc;
735 		return err;
736 	}
737 
738 	for (enum translation_map m = FIRST_MAP; m <= LAST_MAP; m++)
739 		set_inverse_transl(vc, dict, m);
740 	set_inverse_trans_unicode(vc, dict);
741 	dflt = dict;
742 	return err;
743 }
744 EXPORT_SYMBOL(con_set_default_unimap);
745 
746 /**
747  *	con_copy_unimap		-	copy unimap between two vts
748  *	@dst_vc: target
749  *	@src_vc: source
750  *
751  *	The caller must hold the console lock when invoking this method
752  */
753 int con_copy_unimap(struct vc_data *dst_vc, struct vc_data *src_vc)
754 {
755 	struct uni_pagedict *src;
756 
757 	if (!*src_vc->vc_uni_pagedir_loc)
758 		return -EINVAL;
759 	if (*dst_vc->vc_uni_pagedir_loc == *src_vc->vc_uni_pagedir_loc)
760 		return 0;
761 	con_free_unimap(dst_vc);
762 	src = *src_vc->vc_uni_pagedir_loc;
763 	src->refcount++;
764 	*dst_vc->vc_uni_pagedir_loc = src;
765 	return 0;
766 }
767 EXPORT_SYMBOL(con_copy_unimap);
768 
769 /*
770  *	con_get_unimap		-	get the unicode map
771  *
772  *	Read the console unicode data for this console. Called from the ioctl
773  *	handlers.
774  */
775 int con_get_unimap(struct vc_data *vc, ushort ct, ushort __user *uct,
776 		struct unipair __user *list)
777 {
778 	ushort ect;
779 	struct uni_pagedict *dict;
780 	struct unipair *unilist;
781 	unsigned int d, r, g;
782 	int ret = 0;
783 
784 	unilist = kvmalloc_array(ct, sizeof(*unilist), GFP_KERNEL);
785 	if (!unilist)
786 		return -ENOMEM;
787 
788 	console_lock();
789 
790 	ect = 0;
791 	dict = *vc->vc_uni_pagedir_loc;
792 	if (!dict)
793 		goto unlock;
794 
795 	for (d = 0; d < UNI_DIRS; d++) {
796 		u16 **dir = dict->uni_pgdir[d];
797 		if (!dir)
798 			continue;
799 
800 		for (r = 0; r < UNI_DIR_ROWS; r++) {
801 			u16 *row = dir[r];
802 			if (!row)
803 				continue;
804 
805 			for (g = 0; g < UNI_ROW_GLYPHS; g++, row++) {
806 				if (*row >= MAX_GLYPH)
807 					continue;
808 				if (ect < ct) {
809 					unilist[ect].unicode = UNI(d, r, g);
810 					unilist[ect].fontpos = *row;
811 				}
812 				ect++;
813 			}
814 		}
815 	}
816 unlock:
817 	console_unlock();
818 	if (copy_to_user(list, unilist, min(ect, ct) * sizeof(*unilist)))
819 		ret = -EFAULT;
820 	if (put_user(ect, uct))
821 		ret = -EFAULT;
822 	kvfree(unilist);
823 	return ret ? ret : (ect <= ct) ? 0 : -ENOMEM;
824 }
825 
826 /*
827  * Always use USER_MAP. These functions are used by the keyboard,
828  * which shouldn't be affected by G0/G1 switching, etc.
829  * If the user map still contains default values, i.e. the
830  * direct-to-font mapping, then assume user is using Latin1.
831  *
832  * FIXME: at some point we need to decide if we want to lock the table
833  * update element itself via the keyboard_event_lock for consistency with the
834  * keyboard driver as well as the consoles
835  */
836 /* may be called during an interrupt */
837 u32 conv_8bit_to_uni(unsigned char c)
838 {
839 	unsigned short uni = translations[USER_MAP][c];
840 	return uni == (0xf000 | c) ? c : uni;
841 }
842 
843 int conv_uni_to_8bit(u32 uni)
844 {
845 	int c;
846 	for (c = 0; c < ARRAY_SIZE(translations[USER_MAP]); c++)
847 		if (translations[USER_MAP][c] == uni ||
848 		   (translations[USER_MAP][c] == (c | 0xf000) && uni == c))
849 			return c;
850 	return -1;
851 }
852 
853 int conv_uni_to_pc(struct vc_data *conp, long ucs)
854 {
855 	struct uni_pagedict *dict;
856 	u16 **dir, *row, glyph;
857 
858 	/* Only 16-bit codes supported at this time */
859 	if (ucs > 0xffff)
860 		return -4;		/* Not found */
861 	else if (ucs < 0x20)
862 		return -1;		/* Not a printable character */
863 	else if (ucs == 0xfeff || (ucs >= 0x200b && ucs <= 0x200f))
864 		return -2;			/* Zero-width space */
865 	/*
866 	 * UNI_DIRECT_BASE indicates the start of the region in the User Zone
867 	 * which always has a 1:1 mapping to the currently loaded font.  The
868 	 * UNI_DIRECT_MASK indicates the bit span of the region.
869 	 */
870 	else if ((ucs & ~UNI_DIRECT_MASK) == UNI_DIRECT_BASE)
871 		return ucs & UNI_DIRECT_MASK;
872 
873 	dict = *conp->vc_uni_pagedir_loc;
874 	if (!dict)
875 		return -3;
876 
877 	dir = dict->uni_pgdir[UNI_DIR(ucs)];
878 	if (!dir)
879 		return -4;
880 
881 	row = dir[UNI_ROW(ucs)];
882 	if (!row)
883 		return -4;
884 
885 	glyph = row[UNI_GLYPH(ucs)];
886 	if (glyph >= MAX_GLYPH)
887 		return -4;
888 
889 	return glyph;
890 }
891 
892 /*
893  * This is called at sys_setup time, after memory and the console are
894  * initialized.  It must be possible to call kmalloc(..., GFP_KERNEL)
895  * from this function, hence the call from sys_setup.
896  */
897 void __init
898 console_map_init(void)
899 {
900 	int i;
901 
902 	for (i = 0; i < MAX_NR_CONSOLES; i++)
903 		if (vc_cons_allocated(i) && !*vc_cons[i].d->vc_uni_pagedir_loc)
904 			con_set_default_unimap(vc_cons[i].d);
905 }
906 
907