xref: /openbmc/linux/drivers/tty/vt/consolemap.c (revision 01ddc0dabd1bd3bb8a1c0ad87887882653034c01)
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 *p)
419 {
420 	u16 **p1;
421 	int i, j;
422 
423 	if (p == dflt)
424 		dflt = NULL;
425 	for (i = 0; i < UNI_DIRS; i++) {
426 		p1 = p->uni_pgdir[i];
427 		if (p1 != NULL) {
428 			for (j = 0; j < UNI_DIR_ROWS; j++)
429 				kfree(p1[j]);
430 			kfree(p1);
431 		}
432 		p->uni_pgdir[i] = NULL;
433 	}
434 	for (i = 0; i < ARRAY_SIZE(p->inverse_translations); i++) {
435 		kfree(p->inverse_translations[i]);
436 		p->inverse_translations[i] = NULL;
437 	}
438 	kfree(p->inverse_trans_unicode);
439 	p->inverse_trans_unicode = NULL;
440 }
441 
442 /* Caller must hold the console lock */
443 void con_free_unimap(struct vc_data *vc)
444 {
445 	struct uni_pagedict *p;
446 
447 	p = *vc->vc_uni_pagedir_loc;
448 	if (!p)
449 		return;
450 	*vc->vc_uni_pagedir_loc = NULL;
451 	if (--p->refcount)
452 		return;
453 	con_release_unimap(p);
454 	kfree(p);
455 }
456 
457 static int con_unify_unimap(struct vc_data *conp, struct uni_pagedict *dict1)
458 {
459 	struct uni_pagedict *dict2;
460 	unsigned int cons, d, r;
461 
462 	for (cons = 0; cons < MAX_NR_CONSOLES; cons++) {
463 		if (!vc_cons_allocated(cons))
464 			continue;
465 		dict2 = *vc_cons[cons].d->vc_uni_pagedir_loc;
466 		if (!dict2 || dict2 == dict1 || dict2->sum != dict1->sum)
467 			continue;
468 		for (d = 0; d < UNI_DIRS; d++) {
469 			u16 **dir1 = dict1->uni_pgdir[d];
470 			u16 **dir2 = dict2->uni_pgdir[d];
471 			if (!dir1 && !dir2)
472 				continue;
473 			if (!dir1 || !dir2)
474 				break;
475 			for (r = 0; r < UNI_DIR_ROWS; r++) {
476 				if (!dir1[r] && !dir2[r])
477 					continue;
478 				if (!dir1[r] || !dir2[r])
479 					break;
480 				if (memcmp(dir1[r], dir2[r], UNI_ROW_GLYPHS *
481 							sizeof(*dir1[r])))
482 					break;
483 			}
484 			if (r < UNI_DIR_ROWS)
485 				break;
486 		}
487 		if (d == UNI_DIRS) {
488 			dict2->refcount++;
489 			*conp->vc_uni_pagedir_loc = dict2;
490 			con_release_unimap(dict1);
491 			kfree(dict1);
492 			return 1;
493 		}
494 	}
495 	return 0;
496 }
497 
498 static int
499 con_insert_unipair(struct uni_pagedict *p, u_short unicode, u_short fontpos)
500 {
501 	u16 **dir, *row;
502 	unsigned int n;
503 
504 	n = UNI_DIR(unicode);
505 	dir = p->uni_pgdir[n];
506 	if (!dir) {
507 		dir = p->uni_pgdir[n] = kcalloc(UNI_DIR_ROWS, sizeof(*dir),
508 				GFP_KERNEL);
509 		if (!dir)
510 			return -ENOMEM;
511 	}
512 
513 	n = UNI_ROW(unicode);
514 	row = dir[n];
515 	if (!row) {
516 		row = dir[n] = kmalloc_array(UNI_ROW_GLYPHS, sizeof(*row),
517 				GFP_KERNEL);
518 		if (!row)
519 			return -ENOMEM;
520 		/* No glyphs for the characters (yet) */
521 		memset(row, 0xff, UNI_ROW_GLYPHS * sizeof(*row));
522 	}
523 
524 	row[UNI_GLYPH(unicode)] = fontpos;
525 
526 	p->sum += (fontpos << 20U) + unicode;
527 
528 	return 0;
529 }
530 
531 /* Caller must hold the lock */
532 static int con_do_clear_unimap(struct vc_data *vc)
533 {
534 	struct uni_pagedict *old = *vc->vc_uni_pagedir_loc;
535 
536 	if (!old || --old->refcount) {
537 		struct uni_pagedict *new = kzalloc(sizeof(*new), GFP_KERNEL);
538 		if (!new) {
539 			if (old)
540 				old->refcount++;
541 			return -ENOMEM;
542 		}
543 		new->refcount = 1;
544 		*vc->vc_uni_pagedir_loc = new;
545 	} else {
546 		if (old == dflt)
547 			dflt = NULL;
548 		old->refcount++;
549 		old->sum = 0;
550 		con_release_unimap(old);
551 	}
552 	return 0;
553 }
554 
555 int con_clear_unimap(struct vc_data *vc)
556 {
557 	int ret;
558 	console_lock();
559 	ret = con_do_clear_unimap(vc);
560 	console_unlock();
561 	return ret;
562 }
563 
564 static struct uni_pagedict *con_unshare_unimap(struct vc_data *vc,
565 		struct uni_pagedict *p)
566 {
567 	struct uni_pagedict *q;
568 	u16 **p1, *p2, l;
569 	int ret;
570 	int i, j, k;
571 
572 	ret = con_do_clear_unimap(vc);
573 	if (ret)
574 		return ERR_PTR(ret);
575 
576 	/*
577 	 * Since refcount was > 1, con_clear_unimap() allocated a new
578 	 * uni_pagedict for this vc.  Re: p != q
579 	 */
580 	q = *vc->vc_uni_pagedir_loc;
581 
582 	/*
583 	 * uni_pgdir is a 32*32*64 table with rows allocated when its first
584 	 * entry is added. The unicode value must still be incremented for
585 	 * empty rows. We are copying entries from "p" (old) to "q" (new).
586 	 */
587 	l = 0;		/* unicode value */
588 	for (i = 0; i < UNI_DIRS; i++) {
589 		p1 = p->uni_pgdir[i];
590 		if (!p1) {
591 			/* Account for empty table */
592 			l += UNI_DIR_ROWS * UNI_ROW_GLYPHS;
593 			continue;
594 		}
595 
596 		for (j = 0; j < UNI_DIR_ROWS; j++) {
597 			p2 = p1[j];
598 			if (!p2) {
599 				/* Account for row of 64 empty entries */
600 				l += UNI_ROW_GLYPHS;
601 				continue;
602 			}
603 
604 			for (k = 0; k < UNI_ROW_GLYPHS; k++, l++) {
605 				if (p2[k] == 0xffff)
606 					continue;
607 				/*
608 				 * Found one, copy entry for unicode l with
609 				 * fontpos value p2[k].
610 				 */
611 				ret = con_insert_unipair(q, l, p2[k]);
612 				if (ret) {
613 					p->refcount++;
614 					*vc->vc_uni_pagedir_loc = p;
615 					con_release_unimap(q);
616 					kfree(q);
617 					return ERR_PTR(ret);
618 				}
619 			}
620 		}
621 	}
622 
623 	return q;
624 }
625 
626 int con_set_unimap(struct vc_data *vc, ushort ct, struct unipair __user *list)
627 {
628 	int err = 0, err1;
629 	struct uni_pagedict *p;
630 	struct unipair *unilist, *plist;
631 
632 	if (!ct)
633 		return 0;
634 
635 	unilist = vmemdup_user(list, array_size(sizeof(*unilist), ct));
636 	if (IS_ERR(unilist))
637 		return PTR_ERR(unilist);
638 
639 	console_lock();
640 
641 	/* Save original vc_unipagdir_loc in case we allocate a new one */
642 	p = *vc->vc_uni_pagedir_loc;
643 	if (!p) {
644 		err = -EINVAL;
645 		goto out_unlock;
646 	}
647 
648 	if (p->refcount > 1) {
649 		p = con_unshare_unimap(vc, p);
650 		if (IS_ERR(p)) {
651 			err = PTR_ERR(p);
652 			goto out_unlock;
653 		}
654 	} else if (p == dflt) {
655 		dflt = NULL;
656 	}
657 
658 	/*
659 	 * Insert user specified unicode pairs into new table.
660 	 */
661 	for (plist = unilist; ct; ct--, plist++) {
662 		err1 = con_insert_unipair(p, plist->unicode, plist->fontpos);
663 		if (err1)
664 			err = err1;
665 	}
666 
667 	/*
668 	 * Merge with fontmaps of any other virtual consoles.
669 	 */
670 	if (con_unify_unimap(vc, p))
671 		goto out_unlock;
672 
673 	for (enum translation_map m = FIRST_MAP; m <= LAST_MAP; m++)
674 		set_inverse_transl(vc, p, m); /* Update inverse translations */
675 	set_inverse_trans_unicode(vc, p);
676 
677 out_unlock:
678 	console_unlock();
679 	kvfree(unilist);
680 	return err;
681 }
682 
683 /**
684  *	con_set_default_unimap	-	set default unicode map
685  *	@vc: the console we are updating
686  *
687  *	Loads the unimap for the hardware font, as defined in uni_hash.tbl.
688  *	The representation used was the most compact I could come up
689  *	with.  This routine is executed at video setup, and when the
690  *	PIO_FONTRESET ioctl is called.
691  *
692  *	The caller must hold the console lock
693  */
694 int con_set_default_unimap(struct vc_data *vc)
695 {
696 	int i, j, err = 0, err1;
697 	u16 *q;
698 	struct uni_pagedict *p;
699 
700 	if (dflt) {
701 		p = *vc->vc_uni_pagedir_loc;
702 		if (p == dflt)
703 			return 0;
704 
705 		dflt->refcount++;
706 		*vc->vc_uni_pagedir_loc = dflt;
707 		if (p && !--p->refcount) {
708 			con_release_unimap(p);
709 			kfree(p);
710 		}
711 		return 0;
712 	}
713 
714 	/* The default font is always 256 characters */
715 
716 	err = con_do_clear_unimap(vc);
717 	if (err)
718 		return err;
719 
720 	p = *vc->vc_uni_pagedir_loc;
721 	q = dfont_unitable;
722 
723 	for (i = 0; i < 256; i++)
724 		for (j = dfont_unicount[i]; j; j--) {
725 			err1 = con_insert_unipair(p, *(q++), i);
726 			if (err1)
727 				err = err1;
728 		}
729 
730 	if (con_unify_unimap(vc, p)) {
731 		dflt = *vc->vc_uni_pagedir_loc;
732 		return err;
733 	}
734 
735 	for (enum translation_map m = FIRST_MAP; m <= LAST_MAP; m++)
736 		set_inverse_transl(vc, p, m);	/* Update all inverse translations */
737 	set_inverse_trans_unicode(vc, p);
738 	dflt = p;
739 	return err;
740 }
741 EXPORT_SYMBOL(con_set_default_unimap);
742 
743 /**
744  *	con_copy_unimap		-	copy unimap between two vts
745  *	@dst_vc: target
746  *	@src_vc: source
747  *
748  *	The caller must hold the console lock when invoking this method
749  */
750 int con_copy_unimap(struct vc_data *dst_vc, struct vc_data *src_vc)
751 {
752 	struct uni_pagedict *q;
753 
754 	if (!*src_vc->vc_uni_pagedir_loc)
755 		return -EINVAL;
756 	if (*dst_vc->vc_uni_pagedir_loc == *src_vc->vc_uni_pagedir_loc)
757 		return 0;
758 	con_free_unimap(dst_vc);
759 	q = *src_vc->vc_uni_pagedir_loc;
760 	q->refcount++;
761 	*dst_vc->vc_uni_pagedir_loc = q;
762 	return 0;
763 }
764 EXPORT_SYMBOL(con_copy_unimap);
765 
766 /*
767  *	con_get_unimap		-	get the unicode map
768  *
769  *	Read the console unicode data for this console. Called from the ioctl
770  *	handlers.
771  */
772 int con_get_unimap(struct vc_data *vc, ushort ct, ushort __user *uct,
773 		struct unipair __user *list)
774 {
775 	int i, j, k, ret = 0;
776 	ushort ect;
777 	u16 **p1, *p2;
778 	struct uni_pagedict *p;
779 	struct unipair *unilist;
780 
781 	unilist = kvmalloc_array(ct, sizeof(*unilist), GFP_KERNEL);
782 	if (!unilist)
783 		return -ENOMEM;
784 
785 	console_lock();
786 
787 	ect = 0;
788 	p = *vc->vc_uni_pagedir_loc;
789 	if (!p)
790 		goto unlock;
791 
792 	for (i = 0; i < UNI_DIRS; i++) {
793 		p1 = p->uni_pgdir[i];
794 		if (!p1)
795 			continue;
796 
797 		for (j = 0; j < UNI_DIR_ROWS; j++, p1++) {
798 			p2 = *p1;
799 			if (!p2)
800 				continue;
801 
802 			for (k = 0; k < UNI_ROW_GLYPHS; k++, p2++) {
803 				if (*p2 >= MAX_GLYPH)
804 					continue;
805 				if (ect < ct) {
806 					unilist[ect].unicode = UNI(i, j, k);
807 					unilist[ect].fontpos = *p2;
808 				}
809 				ect++;
810 			}
811 		}
812 	}
813 unlock:
814 	console_unlock();
815 	if (copy_to_user(list, unilist, min(ect, ct) * sizeof(*unilist)))
816 		ret = -EFAULT;
817 	if (put_user(ect, uct))
818 		ret = -EFAULT;
819 	kvfree(unilist);
820 	return ret ? ret : (ect <= ct) ? 0 : -ENOMEM;
821 }
822 
823 /*
824  * Always use USER_MAP. These functions are used by the keyboard,
825  * which shouldn't be affected by G0/G1 switching, etc.
826  * If the user map still contains default values, i.e. the
827  * direct-to-font mapping, then assume user is using Latin1.
828  *
829  * FIXME: at some point we need to decide if we want to lock the table
830  * update element itself via the keyboard_event_lock for consistency with the
831  * keyboard driver as well as the consoles
832  */
833 /* may be called during an interrupt */
834 u32 conv_8bit_to_uni(unsigned char c)
835 {
836 	unsigned short uni = translations[USER_MAP][c];
837 	return uni == (0xf000 | c) ? c : uni;
838 }
839 
840 int conv_uni_to_8bit(u32 uni)
841 {
842 	int c;
843 	for (c = 0; c < ARRAY_SIZE(translations[USER_MAP]); c++)
844 		if (translations[USER_MAP][c] == uni ||
845 		   (translations[USER_MAP][c] == (c | 0xf000) && uni == c))
846 			return c;
847 	return -1;
848 }
849 
850 int
851 conv_uni_to_pc(struct vc_data *conp, long ucs)
852 {
853 	struct uni_pagedict *dict;
854 	u16 **dir, *row, glyph;
855 
856 	/* Only 16-bit codes supported at this time */
857 	if (ucs > 0xffff)
858 		return -4;		/* Not found */
859 	else if (ucs < 0x20)
860 		return -1;		/* Not a printable character */
861 	else if (ucs == 0xfeff || (ucs >= 0x200b && ucs <= 0x200f))
862 		return -2;			/* Zero-width space */
863 	/*
864 	 * UNI_DIRECT_BASE indicates the start of the region in the User Zone
865 	 * which always has a 1:1 mapping to the currently loaded font.  The
866 	 * UNI_DIRECT_MASK indicates the bit span of the region.
867 	 */
868 	else if ((ucs & ~UNI_DIRECT_MASK) == UNI_DIRECT_BASE)
869 		return ucs & UNI_DIRECT_MASK;
870 
871 	if (!*conp->vc_uni_pagedir_loc)
872 		return -3;
873 
874 	dict = *conp->vc_uni_pagedir_loc;
875 	if ((dir = dict->uni_pgdir[UNI_DIR(ucs)]) &&
876 	    (row = dir[UNI_ROW(ucs)]) &&
877 	    (glyph = row[UNI_GLYPH(ucs)]) < MAX_GLYPH)
878 		return glyph;
879 
880 	return -4;		/* not found */
881 }
882 
883 /*
884  * This is called at sys_setup time, after memory and the console are
885  * initialized.  It must be possible to call kmalloc(..., GFP_KERNEL)
886  * from this function, hence the call from sys_setup.
887  */
888 void __init
889 console_map_init(void)
890 {
891 	int i;
892 
893 	for (i = 0; i < MAX_NR_CONSOLES; i++)
894 		if (vc_cons_allocated(i) && !*vc_cons[i].d->vc_uni_pagedir_loc)
895 			con_set_default_unimap(vc_cons[i].d);
896 }
897 
898