1b2441318SGreg Kroah-Hartman // SPDX-License-Identifier: GPL-2.0
28f933b10SRalf Hoppe /*
38f933b10SRalf Hoppe * HMC Drive FTP Services
48f933b10SRalf Hoppe *
58f933b10SRalf Hoppe * Copyright IBM Corp. 2013
68f933b10SRalf Hoppe * Author(s): Ralf Hoppe (rhoppe@de.ibm.com)
78f933b10SRalf Hoppe */
88f933b10SRalf Hoppe
98f933b10SRalf Hoppe #define KMSG_COMPONENT "hmcdrv"
108f933b10SRalf Hoppe #define pr_fmt(fmt) KMSG_COMPONENT ": " fmt
118f933b10SRalf Hoppe
128f933b10SRalf Hoppe #include <linux/kernel.h>
138f933b10SRalf Hoppe #include <linux/slab.h>
148f933b10SRalf Hoppe #include <linux/uaccess.h>
158f933b10SRalf Hoppe #include <linux/export.h>
168f933b10SRalf Hoppe
178f933b10SRalf Hoppe #include <linux/ctype.h>
188f933b10SRalf Hoppe #include <linux/crc16.h>
198f933b10SRalf Hoppe
208f933b10SRalf Hoppe #include "hmcdrv_ftp.h"
218f933b10SRalf Hoppe #include "hmcdrv_cache.h"
228f933b10SRalf Hoppe #include "sclp_ftp.h"
238f933b10SRalf Hoppe #include "diag_ftp.h"
248f933b10SRalf Hoppe
258f933b10SRalf Hoppe /**
268f933b10SRalf Hoppe * struct hmcdrv_ftp_ops - HMC drive FTP operations
278f933b10SRalf Hoppe * @startup: startup function
288f933b10SRalf Hoppe * @shutdown: shutdown function
29*7d665612SHeiko Carstens * @transfer: FTP transfer function
308f933b10SRalf Hoppe */
318f933b10SRalf Hoppe struct hmcdrv_ftp_ops {
328f933b10SRalf Hoppe int (*startup)(void);
338f933b10SRalf Hoppe void (*shutdown)(void);
348f933b10SRalf Hoppe ssize_t (*transfer)(const struct hmcdrv_ftp_cmdspec *ftp,
358f933b10SRalf Hoppe size_t *fsize);
368f933b10SRalf Hoppe };
378f933b10SRalf Hoppe
388f933b10SRalf Hoppe static enum hmcdrv_ftp_cmdid hmcdrv_ftp_cmd_getid(const char *cmd, int len);
398f933b10SRalf Hoppe static int hmcdrv_ftp_parse(char *cmd, struct hmcdrv_ftp_cmdspec *ftp);
408f933b10SRalf Hoppe
41c967e1dfSAya Mahfouz static const struct hmcdrv_ftp_ops *hmcdrv_ftp_funcs; /* current operations */
428f933b10SRalf Hoppe static DEFINE_MUTEX(hmcdrv_ftp_mutex); /* mutex for hmcdrv_ftp_funcs */
438f933b10SRalf Hoppe static unsigned hmcdrv_ftp_refcnt; /* start/shutdown reference counter */
448f933b10SRalf Hoppe
458f933b10SRalf Hoppe /**
468f933b10SRalf Hoppe * hmcdrv_ftp_cmd_getid() - determine FTP command ID from a command string
478f933b10SRalf Hoppe * @cmd: FTP command string (NOT zero-terminated)
488f933b10SRalf Hoppe * @len: length of FTP command string in @cmd
498f933b10SRalf Hoppe */
hmcdrv_ftp_cmd_getid(const char * cmd,int len)508f933b10SRalf Hoppe static enum hmcdrv_ftp_cmdid hmcdrv_ftp_cmd_getid(const char *cmd, int len)
518f933b10SRalf Hoppe {
528f933b10SRalf Hoppe /* HMC FTP command descriptor */
538f933b10SRalf Hoppe struct hmcdrv_ftp_cmd_desc {
548f933b10SRalf Hoppe const char *str; /* command string */
558f933b10SRalf Hoppe enum hmcdrv_ftp_cmdid cmd; /* associated command as enum */
568f933b10SRalf Hoppe };
578f933b10SRalf Hoppe
588f933b10SRalf Hoppe /* Description of all HMC drive FTP commands
598f933b10SRalf Hoppe *
608f933b10SRalf Hoppe * Notes:
618f933b10SRalf Hoppe * 1. Array size should be a prime number.
628f933b10SRalf Hoppe * 2. Do not change the order of commands in table (because the
638f933b10SRalf Hoppe * index is determined by CRC % ARRAY_SIZE).
648f933b10SRalf Hoppe * 3. Original command 'nlist' was renamed, else the CRC would
658f933b10SRalf Hoppe * collide with 'append' (see point 2).
668f933b10SRalf Hoppe */
678f933b10SRalf Hoppe static const struct hmcdrv_ftp_cmd_desc ftpcmds[7] = {
688f933b10SRalf Hoppe
698f933b10SRalf Hoppe {.str = "get", /* [0] get (CRC = 0x68eb) */
708f933b10SRalf Hoppe .cmd = HMCDRV_FTP_GET},
718f933b10SRalf Hoppe {.str = "dir", /* [1] dir (CRC = 0x6a9e) */
728f933b10SRalf Hoppe .cmd = HMCDRV_FTP_DIR},
738f933b10SRalf Hoppe {.str = "delete", /* [2] delete (CRC = 0x53ae) */
748f933b10SRalf Hoppe .cmd = HMCDRV_FTP_DELETE},
758f933b10SRalf Hoppe {.str = "nls", /* [3] nls (CRC = 0xf87c) */
768f933b10SRalf Hoppe .cmd = HMCDRV_FTP_NLIST},
778f933b10SRalf Hoppe {.str = "put", /* [4] put (CRC = 0xac56) */
788f933b10SRalf Hoppe .cmd = HMCDRV_FTP_PUT},
798f933b10SRalf Hoppe {.str = "append", /* [5] append (CRC = 0xf56e) */
808f933b10SRalf Hoppe .cmd = HMCDRV_FTP_APPEND},
818f933b10SRalf Hoppe {.str = NULL} /* [6] unused */
828f933b10SRalf Hoppe };
838f933b10SRalf Hoppe
848f933b10SRalf Hoppe const struct hmcdrv_ftp_cmd_desc *pdesc;
858f933b10SRalf Hoppe
868f933b10SRalf Hoppe u16 crc = 0xffffU;
878f933b10SRalf Hoppe
888f933b10SRalf Hoppe if (len == 0)
898f933b10SRalf Hoppe return HMCDRV_FTP_NOOP; /* error indiactor */
908f933b10SRalf Hoppe
918f933b10SRalf Hoppe crc = crc16(crc, cmd, len);
928f933b10SRalf Hoppe pdesc = ftpcmds + (crc % ARRAY_SIZE(ftpcmds));
938f933b10SRalf Hoppe pr_debug("FTP command '%s' has CRC 0x%04x, at table pos. %lu\n",
948f933b10SRalf Hoppe cmd, crc, (crc % ARRAY_SIZE(ftpcmds)));
958f933b10SRalf Hoppe
968f933b10SRalf Hoppe if (!pdesc->str || strncmp(pdesc->str, cmd, len))
978f933b10SRalf Hoppe return HMCDRV_FTP_NOOP;
988f933b10SRalf Hoppe
998f933b10SRalf Hoppe pr_debug("FTP command '%s' found, with ID %d\n",
1008f933b10SRalf Hoppe pdesc->str, pdesc->cmd);
1018f933b10SRalf Hoppe
1028f933b10SRalf Hoppe return pdesc->cmd;
1038f933b10SRalf Hoppe }
1048f933b10SRalf Hoppe
1058f933b10SRalf Hoppe /**
1068f933b10SRalf Hoppe * hmcdrv_ftp_parse() - HMC drive FTP command parser
1078f933b10SRalf Hoppe * @cmd: FTP command string "<cmd> <filename>"
1088f933b10SRalf Hoppe * @ftp: Pointer to FTP command specification buffer (output)
1098f933b10SRalf Hoppe *
1108f933b10SRalf Hoppe * Return: 0 on success, else a (negative) error code
1118f933b10SRalf Hoppe */
hmcdrv_ftp_parse(char * cmd,struct hmcdrv_ftp_cmdspec * ftp)1128f933b10SRalf Hoppe static int hmcdrv_ftp_parse(char *cmd, struct hmcdrv_ftp_cmdspec *ftp)
1138f933b10SRalf Hoppe {
1148f933b10SRalf Hoppe char *start;
1158f933b10SRalf Hoppe int argc = 0;
1168f933b10SRalf Hoppe
1178f933b10SRalf Hoppe ftp->id = HMCDRV_FTP_NOOP;
1188f933b10SRalf Hoppe ftp->fname = NULL;
1198f933b10SRalf Hoppe
1208f933b10SRalf Hoppe while (*cmd != '\0') {
1218f933b10SRalf Hoppe
1228f933b10SRalf Hoppe while (isspace(*cmd))
1238f933b10SRalf Hoppe ++cmd;
1248f933b10SRalf Hoppe
1258f933b10SRalf Hoppe if (*cmd == '\0')
1268f933b10SRalf Hoppe break;
1278f933b10SRalf Hoppe
1288f933b10SRalf Hoppe start = cmd;
1298f933b10SRalf Hoppe
1308f933b10SRalf Hoppe switch (argc) {
1318f933b10SRalf Hoppe case 0: /* 1st argument (FTP command) */
1328f933b10SRalf Hoppe while ((*cmd != '\0') && !isspace(*cmd))
1338f933b10SRalf Hoppe ++cmd;
1348f933b10SRalf Hoppe ftp->id = hmcdrv_ftp_cmd_getid(start, cmd - start);
1358f933b10SRalf Hoppe break;
1368f933b10SRalf Hoppe case 1: /* 2nd / last argument (rest of line) */
1378f933b10SRalf Hoppe while ((*cmd != '\0') && !iscntrl(*cmd))
1388f933b10SRalf Hoppe ++cmd;
1398f933b10SRalf Hoppe ftp->fname = start;
1402c7749b9SJoe Perches fallthrough;
1418f933b10SRalf Hoppe default:
1428f933b10SRalf Hoppe *cmd = '\0';
1438f933b10SRalf Hoppe break;
1448f933b10SRalf Hoppe } /* switch */
1458f933b10SRalf Hoppe
1468f933b10SRalf Hoppe ++argc;
1478f933b10SRalf Hoppe } /* while */
1488f933b10SRalf Hoppe
1498f933b10SRalf Hoppe if (!ftp->fname || (ftp->id == HMCDRV_FTP_NOOP))
1508f933b10SRalf Hoppe return -EINVAL;
1518f933b10SRalf Hoppe
1528f933b10SRalf Hoppe return 0;
1538f933b10SRalf Hoppe }
1548f933b10SRalf Hoppe
1558f933b10SRalf Hoppe /**
1568f933b10SRalf Hoppe * hmcdrv_ftp_do() - perform a HMC drive FTP, with data from kernel-space
1578f933b10SRalf Hoppe * @ftp: pointer to FTP command specification
1588f933b10SRalf Hoppe *
1598f933b10SRalf Hoppe * Return: number of bytes read/written or a negative error code
1608f933b10SRalf Hoppe */
hmcdrv_ftp_do(const struct hmcdrv_ftp_cmdspec * ftp)1618f933b10SRalf Hoppe ssize_t hmcdrv_ftp_do(const struct hmcdrv_ftp_cmdspec *ftp)
1628f933b10SRalf Hoppe {
1638f933b10SRalf Hoppe ssize_t len;
1648f933b10SRalf Hoppe
1658f933b10SRalf Hoppe mutex_lock(&hmcdrv_ftp_mutex);
1668f933b10SRalf Hoppe
1678f933b10SRalf Hoppe if (hmcdrv_ftp_funcs && hmcdrv_ftp_refcnt) {
1688f933b10SRalf Hoppe pr_debug("starting transfer, cmd %d for '%s' at %lld with %zd bytes\n",
1698f933b10SRalf Hoppe ftp->id, ftp->fname, (long long) ftp->ofs, ftp->len);
1708f933b10SRalf Hoppe len = hmcdrv_cache_cmd(ftp, hmcdrv_ftp_funcs->transfer);
1718f933b10SRalf Hoppe } else {
1728f933b10SRalf Hoppe len = -ENXIO;
1738f933b10SRalf Hoppe }
1748f933b10SRalf Hoppe
1758f933b10SRalf Hoppe mutex_unlock(&hmcdrv_ftp_mutex);
1768f933b10SRalf Hoppe return len;
1778f933b10SRalf Hoppe }
1788f933b10SRalf Hoppe EXPORT_SYMBOL(hmcdrv_ftp_do);
1798f933b10SRalf Hoppe
1808f933b10SRalf Hoppe /**
1818f933b10SRalf Hoppe * hmcdrv_ftp_probe() - probe for the HMC drive FTP service
1828f933b10SRalf Hoppe *
1838f933b10SRalf Hoppe * Return: 0 if service is available, else an (negative) error code
1848f933b10SRalf Hoppe */
hmcdrv_ftp_probe(void)1858f933b10SRalf Hoppe int hmcdrv_ftp_probe(void)
1868f933b10SRalf Hoppe {
1878f933b10SRalf Hoppe int rc;
1888f933b10SRalf Hoppe
1898f933b10SRalf Hoppe struct hmcdrv_ftp_cmdspec ftp = {
1908f933b10SRalf Hoppe .id = HMCDRV_FTP_NOOP,
1918f933b10SRalf Hoppe .ofs = 0,
1928f933b10SRalf Hoppe .fname = "",
1938f933b10SRalf Hoppe .len = PAGE_SIZE
1948f933b10SRalf Hoppe };
1958f933b10SRalf Hoppe
1968f933b10SRalf Hoppe ftp.buf = (void *) get_zeroed_page(GFP_KERNEL | GFP_DMA);
1978f933b10SRalf Hoppe
1988f933b10SRalf Hoppe if (!ftp.buf)
1998f933b10SRalf Hoppe return -ENOMEM;
2008f933b10SRalf Hoppe
2018f933b10SRalf Hoppe rc = hmcdrv_ftp_startup();
2028f933b10SRalf Hoppe
2038f933b10SRalf Hoppe if (rc)
2042ec50493SChristophe Jaillet goto out;
2058f933b10SRalf Hoppe
2068f933b10SRalf Hoppe rc = hmcdrv_ftp_do(&ftp);
2078f933b10SRalf Hoppe hmcdrv_ftp_shutdown();
2088f933b10SRalf Hoppe
2098f933b10SRalf Hoppe switch (rc) {
2108f933b10SRalf Hoppe case -ENOENT: /* no such file/media or currently busy, */
2118f933b10SRalf Hoppe case -EBUSY: /* but service seems to be available */
2128f933b10SRalf Hoppe rc = 0;
2138f933b10SRalf Hoppe break;
2148f933b10SRalf Hoppe default: /* leave 'rc' as it is for [0, -EPERM, -E...] */
2158f933b10SRalf Hoppe if (rc > 0)
2168f933b10SRalf Hoppe rc = 0; /* clear length (success) */
2178f933b10SRalf Hoppe break;
2188f933b10SRalf Hoppe } /* switch */
2192ec50493SChristophe Jaillet out:
2202ec50493SChristophe Jaillet free_page((unsigned long) ftp.buf);
2218f933b10SRalf Hoppe return rc;
2228f933b10SRalf Hoppe }
2238f933b10SRalf Hoppe EXPORT_SYMBOL(hmcdrv_ftp_probe);
2248f933b10SRalf Hoppe
2258f933b10SRalf Hoppe /**
2268f933b10SRalf Hoppe * hmcdrv_ftp_cmd() - Perform a HMC drive FTP, with data from user-space
2278f933b10SRalf Hoppe *
2288f933b10SRalf Hoppe * @cmd: FTP command string "<cmd> <filename>"
2298f933b10SRalf Hoppe * @offset: file position to read/write
2308f933b10SRalf Hoppe * @buf: user-space buffer for read/written directory/file
2318f933b10SRalf Hoppe * @len: size of @buf (read/dir) or number of bytes to write
2328f933b10SRalf Hoppe *
2338f933b10SRalf Hoppe * This function must not be called before hmcdrv_ftp_startup() was called.
2348f933b10SRalf Hoppe *
2358f933b10SRalf Hoppe * Return: number of bytes read/written or a negative error code
2368f933b10SRalf Hoppe */
hmcdrv_ftp_cmd(char __kernel * cmd,loff_t offset,char __user * buf,size_t len)2378f933b10SRalf Hoppe ssize_t hmcdrv_ftp_cmd(char __kernel *cmd, loff_t offset,
2388f933b10SRalf Hoppe char __user *buf, size_t len)
2398f933b10SRalf Hoppe {
2408f933b10SRalf Hoppe int order;
2418f933b10SRalf Hoppe
2428f933b10SRalf Hoppe struct hmcdrv_ftp_cmdspec ftp = {.len = len, .ofs = offset};
2438f933b10SRalf Hoppe ssize_t retlen = hmcdrv_ftp_parse(cmd, &ftp);
2448f933b10SRalf Hoppe
2458f933b10SRalf Hoppe if (retlen)
2468f933b10SRalf Hoppe return retlen;
2478f933b10SRalf Hoppe
2488f933b10SRalf Hoppe order = get_order(ftp.len);
2498f933b10SRalf Hoppe ftp.buf = (void *) __get_free_pages(GFP_KERNEL | GFP_DMA, order);
2508f933b10SRalf Hoppe
2518f933b10SRalf Hoppe if (!ftp.buf)
2528f933b10SRalf Hoppe return -ENOMEM;
2538f933b10SRalf Hoppe
2548f933b10SRalf Hoppe switch (ftp.id) {
2558f933b10SRalf Hoppe case HMCDRV_FTP_DIR:
2568f933b10SRalf Hoppe case HMCDRV_FTP_NLIST:
2578f933b10SRalf Hoppe case HMCDRV_FTP_GET:
2588f933b10SRalf Hoppe retlen = hmcdrv_ftp_do(&ftp);
2598f933b10SRalf Hoppe
2608f933b10SRalf Hoppe if ((retlen >= 0) &&
2618f933b10SRalf Hoppe copy_to_user(buf, ftp.buf, retlen))
2628f933b10SRalf Hoppe retlen = -EFAULT;
2638f933b10SRalf Hoppe break;
2648f933b10SRalf Hoppe
2658f933b10SRalf Hoppe case HMCDRV_FTP_PUT:
2668f933b10SRalf Hoppe case HMCDRV_FTP_APPEND:
2678f933b10SRalf Hoppe if (!copy_from_user(ftp.buf, buf, ftp.len))
2688f933b10SRalf Hoppe retlen = hmcdrv_ftp_do(&ftp);
2698f933b10SRalf Hoppe else
2708f933b10SRalf Hoppe retlen = -EFAULT;
2718f933b10SRalf Hoppe break;
2728f933b10SRalf Hoppe
2738f933b10SRalf Hoppe case HMCDRV_FTP_DELETE:
2748f933b10SRalf Hoppe retlen = hmcdrv_ftp_do(&ftp);
2758f933b10SRalf Hoppe break;
2768f933b10SRalf Hoppe
2778f933b10SRalf Hoppe default:
2788f933b10SRalf Hoppe retlen = -EOPNOTSUPP;
2798f933b10SRalf Hoppe break;
2808f933b10SRalf Hoppe }
2818f933b10SRalf Hoppe
2828f933b10SRalf Hoppe free_pages((unsigned long) ftp.buf, order);
2838f933b10SRalf Hoppe return retlen;
2848f933b10SRalf Hoppe }
2858f933b10SRalf Hoppe
2868f933b10SRalf Hoppe /**
2878f933b10SRalf Hoppe * hmcdrv_ftp_startup() - startup of HMC drive FTP functionality for a
2888f933b10SRalf Hoppe * dedicated (owner) instance
2898f933b10SRalf Hoppe *
2908f933b10SRalf Hoppe * Return: 0 on success, else an (negative) error code
2918f933b10SRalf Hoppe */
hmcdrv_ftp_startup(void)2928f933b10SRalf Hoppe int hmcdrv_ftp_startup(void)
2938f933b10SRalf Hoppe {
294c967e1dfSAya Mahfouz static const struct hmcdrv_ftp_ops hmcdrv_ftp_zvm = {
2958f933b10SRalf Hoppe .startup = diag_ftp_startup,
2968f933b10SRalf Hoppe .shutdown = diag_ftp_shutdown,
2978f933b10SRalf Hoppe .transfer = diag_ftp_cmd
2988f933b10SRalf Hoppe };
2998f933b10SRalf Hoppe
300c967e1dfSAya Mahfouz static const struct hmcdrv_ftp_ops hmcdrv_ftp_lpar = {
3018f933b10SRalf Hoppe .startup = sclp_ftp_startup,
3028f933b10SRalf Hoppe .shutdown = sclp_ftp_shutdown,
3038f933b10SRalf Hoppe .transfer = sclp_ftp_cmd
3048f933b10SRalf Hoppe };
3058f933b10SRalf Hoppe
3068f933b10SRalf Hoppe int rc = 0;
3078f933b10SRalf Hoppe
3088f933b10SRalf Hoppe mutex_lock(&hmcdrv_ftp_mutex); /* block transfers while start-up */
3098f933b10SRalf Hoppe
3108f933b10SRalf Hoppe if (hmcdrv_ftp_refcnt == 0) {
3118f933b10SRalf Hoppe if (MACHINE_IS_VM)
3128f933b10SRalf Hoppe hmcdrv_ftp_funcs = &hmcdrv_ftp_zvm;
3138f933b10SRalf Hoppe else if (MACHINE_IS_LPAR || MACHINE_IS_KVM)
3148f933b10SRalf Hoppe hmcdrv_ftp_funcs = &hmcdrv_ftp_lpar;
3158f933b10SRalf Hoppe else
3168f933b10SRalf Hoppe rc = -EOPNOTSUPP;
3178f933b10SRalf Hoppe
3188f933b10SRalf Hoppe if (hmcdrv_ftp_funcs)
3198f933b10SRalf Hoppe rc = hmcdrv_ftp_funcs->startup();
3208f933b10SRalf Hoppe }
3218f933b10SRalf Hoppe
3228f933b10SRalf Hoppe if (!rc)
3238f933b10SRalf Hoppe ++hmcdrv_ftp_refcnt;
3248f933b10SRalf Hoppe
3258f933b10SRalf Hoppe mutex_unlock(&hmcdrv_ftp_mutex);
3268f933b10SRalf Hoppe return rc;
3278f933b10SRalf Hoppe }
3288f933b10SRalf Hoppe EXPORT_SYMBOL(hmcdrv_ftp_startup);
3298f933b10SRalf Hoppe
3308f933b10SRalf Hoppe /**
3318f933b10SRalf Hoppe * hmcdrv_ftp_shutdown() - shutdown of HMC drive FTP functionality for a
3328f933b10SRalf Hoppe * dedicated (owner) instance
3338f933b10SRalf Hoppe */
hmcdrv_ftp_shutdown(void)3348f933b10SRalf Hoppe void hmcdrv_ftp_shutdown(void)
3358f933b10SRalf Hoppe {
3368f933b10SRalf Hoppe mutex_lock(&hmcdrv_ftp_mutex);
3378f933b10SRalf Hoppe --hmcdrv_ftp_refcnt;
3388f933b10SRalf Hoppe
3398f933b10SRalf Hoppe if ((hmcdrv_ftp_refcnt == 0) && hmcdrv_ftp_funcs)
3408f933b10SRalf Hoppe hmcdrv_ftp_funcs->shutdown();
3418f933b10SRalf Hoppe
3428f933b10SRalf Hoppe mutex_unlock(&hmcdrv_ftp_mutex);
3438f933b10SRalf Hoppe }
3448f933b10SRalf Hoppe EXPORT_SYMBOL(hmcdrv_ftp_shutdown);
345