Commit | Line | Data |
---|---|---|
8f933b10 RH |
1 | /* |
2 | * DIAGNOSE X'2C4' instruction based HMC FTP services, useable on z/VM | |
3 | * | |
4 | * Copyright IBM Corp. 2013 | |
5 | * Author(s): Ralf Hoppe (rhoppe@de.ibm.com) | |
6 | * | |
7 | */ | |
8 | ||
9 | #define KMSG_COMPONENT "hmcdrv" | |
10 | #define pr_fmt(fmt) KMSG_COMPONENT ": " fmt | |
11 | ||
12 | #include <linux/kernel.h> | |
13 | #include <linux/mm.h> | |
14 | #include <linux/irq.h> | |
15 | #include <linux/wait.h> | |
16 | #include <linux/string.h> | |
17 | #include <asm/ctl_reg.h> | |
18 | ||
19 | #include "hmcdrv_ftp.h" | |
20 | #include "diag_ftp.h" | |
21 | ||
22 | /* DIAGNOSE X'2C4' return codes in Ry */ | |
23 | #define DIAG_FTP_RET_OK 0 /* HMC FTP started successfully */ | |
24 | #define DIAG_FTP_RET_EBUSY 4 /* HMC FTP service currently busy */ | |
25 | #define DIAG_FTP_RET_EIO 8 /* HMC FTP service I/O error */ | |
26 | /* and an artificial extension */ | |
27 | #define DIAG_FTP_RET_EPERM 2 /* HMC FTP service privilege error */ | |
28 | ||
29 | /* FTP service status codes (after INTR at guest real location 133) */ | |
30 | #define DIAG_FTP_STAT_OK 0U /* request completed successfully */ | |
31 | #define DIAG_FTP_STAT_PGCC 4U /* program check condition */ | |
32 | #define DIAG_FTP_STAT_PGIOE 8U /* paging I/O error */ | |
33 | #define DIAG_FTP_STAT_TIMEOUT 12U /* timeout */ | |
34 | #define DIAG_FTP_STAT_EBASE 16U /* base of error codes from SCLP */ | |
35 | #define DIAG_FTP_STAT_LDFAIL (DIAG_FTP_STAT_EBASE + 1U) /* failed */ | |
36 | #define DIAG_FTP_STAT_LDNPERM (DIAG_FTP_STAT_EBASE + 2U) /* not allowed */ | |
37 | #define DIAG_FTP_STAT_LDRUNS (DIAG_FTP_STAT_EBASE + 3U) /* runs */ | |
38 | #define DIAG_FTP_STAT_LDNRUNS (DIAG_FTP_STAT_EBASE + 4U) /* not runs */ | |
39 | ||
40 | /** | |
41 | * struct diag_ftp_ldfpl - load file FTP parameter list (LDFPL) | |
42 | * @bufaddr: real buffer address (at 4k boundary) | |
43 | * @buflen: length of buffer | |
44 | * @offset: dir/file offset | |
45 | * @intparm: interruption parameter (unused) | |
46 | * @transferred: bytes transferred | |
47 | * @fsize: file size, filled on GET | |
48 | * @failaddr: failing address | |
49 | * @spare: padding | |
50 | * @fident: file name - ASCII | |
51 | */ | |
52 | struct diag_ftp_ldfpl { | |
53 | u64 bufaddr; | |
54 | u64 buflen; | |
55 | u64 offset; | |
56 | u64 intparm; | |
57 | u64 transferred; | |
58 | u64 fsize; | |
59 | u64 failaddr; | |
60 | u64 spare; | |
61 | u8 fident[HMCDRV_FTP_FIDENT_MAX]; | |
62 | } __packed; | |
63 | ||
64 | static DECLARE_COMPLETION(diag_ftp_rx_complete); | |
65 | static int diag_ftp_subcode; | |
66 | ||
67 | /** | |
68 | * diag_ftp_handler() - FTP services IRQ handler | |
69 | * @extirq: external interrupt (sub-) code | |
70 | * @param32: 32-bit interruption parameter from &struct diag_ftp_ldfpl | |
71 | * @param64: unused (for 64-bit interrupt parameters) | |
72 | */ | |
73 | static void diag_ftp_handler(struct ext_code extirq, | |
74 | unsigned int param32, | |
75 | unsigned long param64) | |
76 | { | |
77 | if ((extirq.subcode >> 8) != 8) | |
78 | return; /* not a FTP services sub-code */ | |
79 | ||
80 | inc_irq_stat(IRQEXT_FTP); | |
81 | diag_ftp_subcode = extirq.subcode & 0xffU; | |
82 | complete(&diag_ftp_rx_complete); | |
83 | } | |
84 | ||
85 | /** | |
86 | * diag_ftp_2c4() - DIAGNOSE X'2C4' service call | |
87 | * @fpl: pointer to prepared LDFPL | |
88 | * @cmd: FTP command to be executed | |
89 | * | |
90 | * Performs a DIAGNOSE X'2C4' call with (input/output) FTP parameter list | |
91 | * @fpl and FTP function code @cmd. In case of an error the function does | |
92 | * nothing and returns an (negative) error code. | |
93 | * | |
94 | * Notes: | |
95 | * 1. This function only initiates a transfer, so the caller must wait | |
96 | * for completion (asynchronous execution). | |
97 | * 2. The FTP parameter list @fpl must be aligned to a double-word boundary. | |
98 | * 3. fpl->bufaddr must be a real address, 4k aligned | |
99 | */ | |
100 | static int diag_ftp_2c4(struct diag_ftp_ldfpl *fpl, | |
101 | enum hmcdrv_ftp_cmdid cmd) | |
102 | { | |
103 | int rc; | |
104 | ||
105 | asm volatile( | |
106 | " diag %[addr],%[cmd],0x2c4\n" | |
107 | "0: j 2f\n" | |
108 | "1: la %[rc],%[err]\n" | |
109 | "2:\n" | |
110 | EX_TABLE(0b, 1b) | |
111 | : [rc] "=d" (rc), "+m" (*fpl) | |
112 | : [cmd] "0" (cmd), [addr] "d" (virt_to_phys(fpl)), | |
113 | [err] "i" (DIAG_FTP_RET_EPERM) | |
114 | : "cc"); | |
115 | ||
116 | switch (rc) { | |
117 | case DIAG_FTP_RET_OK: | |
118 | return 0; | |
119 | case DIAG_FTP_RET_EBUSY: | |
120 | return -EBUSY; | |
121 | case DIAG_FTP_RET_EPERM: | |
122 | return -EPERM; | |
123 | case DIAG_FTP_RET_EIO: | |
124 | default: | |
125 | return -EIO; | |
126 | } | |
127 | } | |
128 | ||
129 | /** | |
130 | * diag_ftp_cmd() - executes a DIAG X'2C4' FTP command, targeting a HMC | |
131 | * @ftp: pointer to FTP command specification | |
132 | * @fsize: return of file size (or NULL if undesirable) | |
133 | * | |
134 | * Attention: Notice that this function is not reentrant - so the caller | |
135 | * must ensure locking. | |
136 | * | |
137 | * Return: number of bytes read/written or a (negative) error code | |
138 | */ | |
139 | ssize_t diag_ftp_cmd(const struct hmcdrv_ftp_cmdspec *ftp, size_t *fsize) | |
140 | { | |
141 | struct diag_ftp_ldfpl *ldfpl; | |
142 | ssize_t len; | |
143 | #ifdef DEBUG | |
144 | unsigned long start_jiffies; | |
145 | ||
146 | pr_debug("starting DIAG X'2C4' on '%s', requesting %zd bytes\n", | |
147 | ftp->fname, ftp->len); | |
148 | start_jiffies = jiffies; | |
149 | #endif | |
150 | init_completion(&diag_ftp_rx_complete); | |
151 | ||
152 | ldfpl = (void *) get_zeroed_page(GFP_KERNEL | GFP_DMA); | |
153 | if (!ldfpl) { | |
154 | len = -ENOMEM; | |
155 | goto out; | |
156 | } | |
157 | ||
158 | len = strlcpy(ldfpl->fident, ftp->fname, sizeof(ldfpl->fident)); | |
159 | if (len >= HMCDRV_FTP_FIDENT_MAX) { | |
160 | len = -EINVAL; | |
161 | goto out_free; | |
162 | } | |
163 | ||
164 | ldfpl->transferred = 0; | |
165 | ldfpl->fsize = 0; | |
166 | ldfpl->offset = ftp->ofs; | |
167 | ldfpl->buflen = ftp->len; | |
168 | ldfpl->bufaddr = virt_to_phys(ftp->buf); | |
169 | ||
170 | len = diag_ftp_2c4(ldfpl, ftp->id); | |
171 | if (len) | |
172 | goto out_free; | |
173 | ||
174 | /* | |
175 | * There is no way to cancel the running diag X'2C4', the code | |
176 | * needs to wait unconditionally until the transfer is complete. | |
177 | */ | |
178 | wait_for_completion(&diag_ftp_rx_complete); | |
179 | ||
180 | #ifdef DEBUG | |
181 | pr_debug("completed DIAG X'2C4' after %lu ms\n", | |
182 | (jiffies - start_jiffies) * 1000 / HZ); | |
183 | pr_debug("status of DIAG X'2C4' is %u, with %lld/%lld bytes\n", | |
184 | diag_ftp_subcode, ldfpl->transferred, ldfpl->fsize); | |
185 | #endif | |
186 | ||
187 | switch (diag_ftp_subcode) { | |
188 | case DIAG_FTP_STAT_OK: /* success */ | |
189 | len = ldfpl->transferred; | |
190 | if (fsize) | |
191 | *fsize = ldfpl->fsize; | |
192 | break; | |
193 | case DIAG_FTP_STAT_LDNPERM: | |
194 | len = -EPERM; | |
195 | break; | |
196 | case DIAG_FTP_STAT_LDRUNS: | |
197 | len = -EBUSY; | |
198 | break; | |
199 | case DIAG_FTP_STAT_LDFAIL: | |
200 | len = -ENOENT; /* no such file or media */ | |
201 | break; | |
202 | default: | |
203 | len = -EIO; | |
204 | break; | |
205 | } | |
206 | ||
207 | out_free: | |
208 | free_page((unsigned long) ldfpl); | |
209 | out: | |
210 | return len; | |
211 | } | |
212 | ||
213 | /** | |
214 | * diag_ftp_startup() - startup of FTP services, when running on z/VM | |
215 | * | |
216 | * Return: 0 on success, else an (negative) error code | |
217 | */ | |
218 | int diag_ftp_startup(void) | |
219 | { | |
220 | int rc; | |
221 | ||
222 | rc = register_external_irq(EXT_IRQ_CP_SERVICE, diag_ftp_handler); | |
223 | if (rc) | |
224 | return rc; | |
225 | ||
226 | ctl_set_bit(0, 63 - 22); | |
227 | return 0; | |
228 | } | |
229 | ||
230 | /** | |
231 | * diag_ftp_shutdown() - shutdown of FTP services, when running on z/VM | |
232 | */ | |
233 | void diag_ftp_shutdown(void) | |
234 | { | |
235 | ctl_clear_bit(0, 63 - 22); | |
236 | unregister_external_irq(EXT_IRQ_CP_SERVICE, diag_ftp_handler); | |
237 | } |