Add the rt linux 4.1.3-rt3 as base
[kvmfornfv.git] / kernel / net / 9p / protocol.c
diff --git a/kernel/net/9p/protocol.c b/kernel/net/9p/protocol.c
new file mode 100644 (file)
index 0000000..16d2875
--- /dev/null
@@ -0,0 +1,628 @@
+/*
+ * net/9p/protocol.c
+ *
+ * 9P Protocol Support Code
+ *
+ *  Copyright (C) 2008 by Eric Van Hensbergen <ericvh@gmail.com>
+ *
+ *  Base on code from Anthony Liguori <aliguori@us.ibm.com>
+ *  Copyright (C) 2008 by IBM, Corp.
+ *
+ *  This program is free software; you can redistribute it and/or modify
+ *  it under the terms of the GNU General Public License version 2
+ *  as published by the Free Software Foundation.
+ *
+ *  This program is distributed in the hope that it will be useful,
+ *  but WITHOUT ANY WARRANTY; without even the implied warranty of
+ *  MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ *  GNU General Public License for more details.
+ *
+ *  You should have received a copy of the GNU General Public License
+ *  along with this program; if not, write to:
+ *  Free Software Foundation
+ *  51 Franklin Street, Fifth Floor
+ *  Boston, MA  02111-1301  USA
+ *
+ */
+
+#include <linux/module.h>
+#include <linux/errno.h>
+#include <linux/kernel.h>
+#include <linux/uaccess.h>
+#include <linux/slab.h>
+#include <linux/sched.h>
+#include <linux/stddef.h>
+#include <linux/types.h>
+#include <linux/uio.h>
+#include <net/9p/9p.h>
+#include <net/9p/client.h>
+#include "protocol.h"
+
+#include <trace/events/9p.h>
+
+static int
+p9pdu_writef(struct p9_fcall *pdu, int proto_version, const char *fmt, ...);
+
+void p9stat_free(struct p9_wstat *stbuf)
+{
+       kfree(stbuf->name);
+       kfree(stbuf->uid);
+       kfree(stbuf->gid);
+       kfree(stbuf->muid);
+       kfree(stbuf->extension);
+}
+EXPORT_SYMBOL(p9stat_free);
+
+size_t pdu_read(struct p9_fcall *pdu, void *data, size_t size)
+{
+       size_t len = min(pdu->size - pdu->offset, size);
+       memcpy(data, &pdu->sdata[pdu->offset], len);
+       pdu->offset += len;
+       return size - len;
+}
+
+static size_t pdu_write(struct p9_fcall *pdu, const void *data, size_t size)
+{
+       size_t len = min(pdu->capacity - pdu->size, size);
+       memcpy(&pdu->sdata[pdu->size], data, len);
+       pdu->size += len;
+       return size - len;
+}
+
+static size_t
+pdu_write_u(struct p9_fcall *pdu, struct iov_iter *from, size_t size)
+{
+       size_t len = min(pdu->capacity - pdu->size, size);
+       struct iov_iter i = *from;
+       if (copy_from_iter(&pdu->sdata[pdu->size], len, &i) != len)
+               len = 0;
+
+       pdu->size += len;
+       return size - len;
+}
+
+/*
+       b - int8_t
+       w - int16_t
+       d - int32_t
+       q - int64_t
+       s - string
+       u - numeric uid
+       g - numeric gid
+       S - stat
+       Q - qid
+       D - data blob (int32_t size followed by void *, results are not freed)
+       T - array of strings (int16_t count, followed by strings)
+       R - array of qids (int16_t count, followed by qids)
+       A - stat for 9p2000.L (p9_stat_dotl)
+       ? - if optional = 1, continue parsing
+*/
+
+static int
+p9pdu_vreadf(struct p9_fcall *pdu, int proto_version, const char *fmt,
+       va_list ap)
+{
+       const char *ptr;
+       int errcode = 0;
+
+       for (ptr = fmt; *ptr; ptr++) {
+               switch (*ptr) {
+               case 'b':{
+                               int8_t *val = va_arg(ap, int8_t *);
+                               if (pdu_read(pdu, val, sizeof(*val))) {
+                                       errcode = -EFAULT;
+                                       break;
+                               }
+                       }
+                       break;
+               case 'w':{
+                               int16_t *val = va_arg(ap, int16_t *);
+                               __le16 le_val;
+                               if (pdu_read(pdu, &le_val, sizeof(le_val))) {
+                                       errcode = -EFAULT;
+                                       break;
+                               }
+                               *val = le16_to_cpu(le_val);
+                       }
+                       break;
+               case 'd':{
+                               int32_t *val = va_arg(ap, int32_t *);
+                               __le32 le_val;
+                               if (pdu_read(pdu, &le_val, sizeof(le_val))) {
+                                       errcode = -EFAULT;
+                                       break;
+                               }
+                               *val = le32_to_cpu(le_val);
+                       }
+                       break;
+               case 'q':{
+                               int64_t *val = va_arg(ap, int64_t *);
+                               __le64 le_val;
+                               if (pdu_read(pdu, &le_val, sizeof(le_val))) {
+                                       errcode = -EFAULT;
+                                       break;
+                               }
+                               *val = le64_to_cpu(le_val);
+                       }
+                       break;
+               case 's':{
+                               char **sptr = va_arg(ap, char **);
+                               uint16_t len;
+
+                               errcode = p9pdu_readf(pdu, proto_version,
+                                                               "w", &len);
+                               if (errcode)
+                                       break;
+
+                               *sptr = kmalloc(len + 1, GFP_NOFS);
+                               if (*sptr == NULL) {
+                                       errcode = -EFAULT;
+                                       break;
+                               }
+                               if (pdu_read(pdu, *sptr, len)) {
+                                       errcode = -EFAULT;
+                                       kfree(*sptr);
+                                       *sptr = NULL;
+                               } else
+                                       (*sptr)[len] = 0;
+                       }
+                       break;
+               case 'u': {
+                               kuid_t *uid = va_arg(ap, kuid_t *);
+                               __le32 le_val;
+                               if (pdu_read(pdu, &le_val, sizeof(le_val))) {
+                                       errcode = -EFAULT;
+                                       break;
+                               }
+                               *uid = make_kuid(&init_user_ns,
+                                                le32_to_cpu(le_val));
+                       } break;
+               case 'g': {
+                               kgid_t *gid = va_arg(ap, kgid_t *);
+                               __le32 le_val;
+                               if (pdu_read(pdu, &le_val, sizeof(le_val))) {
+                                       errcode = -EFAULT;
+                                       break;
+                               }
+                               *gid = make_kgid(&init_user_ns,
+                                                le32_to_cpu(le_val));
+                       } break;
+               case 'Q':{
+                               struct p9_qid *qid =
+                                   va_arg(ap, struct p9_qid *);
+
+                               errcode = p9pdu_readf(pdu, proto_version, "bdq",
+                                                     &qid->type, &qid->version,
+                                                     &qid->path);
+                       }
+                       break;
+               case 'S':{
+                               struct p9_wstat *stbuf =
+                                   va_arg(ap, struct p9_wstat *);
+
+                               memset(stbuf, 0, sizeof(struct p9_wstat));
+                               stbuf->n_uid = stbuf->n_muid = INVALID_UID;
+                               stbuf->n_gid = INVALID_GID;
+
+                               errcode =
+                                   p9pdu_readf(pdu, proto_version,
+                                               "wwdQdddqssss?sugu",
+                                               &stbuf->size, &stbuf->type,
+                                               &stbuf->dev, &stbuf->qid,
+                                               &stbuf->mode, &stbuf->atime,
+                                               &stbuf->mtime, &stbuf->length,
+                                               &stbuf->name, &stbuf->uid,
+                                               &stbuf->gid, &stbuf->muid,
+                                               &stbuf->extension,
+                                               &stbuf->n_uid, &stbuf->n_gid,
+                                               &stbuf->n_muid);
+                               if (errcode)
+                                       p9stat_free(stbuf);
+                       }
+                       break;
+               case 'D':{
+                               uint32_t *count = va_arg(ap, uint32_t *);
+                               void **data = va_arg(ap, void **);
+
+                               errcode =
+                                   p9pdu_readf(pdu, proto_version, "d", count);
+                               if (!errcode) {
+                                       *count =
+                                           min_t(uint32_t, *count,
+                                                 pdu->size - pdu->offset);
+                                       *data = &pdu->sdata[pdu->offset];
+                               }
+                       }
+                       break;
+               case 'T':{
+                               uint16_t *nwname = va_arg(ap, uint16_t *);
+                               char ***wnames = va_arg(ap, char ***);
+
+                               errcode = p9pdu_readf(pdu, proto_version,
+                                                               "w", nwname);
+                               if (!errcode) {
+                                       *wnames =
+                                           kmalloc(sizeof(char *) * *nwname,
+                                                   GFP_NOFS);
+                                       if (!*wnames)
+                                               errcode = -ENOMEM;
+                               }
+
+                               if (!errcode) {
+                                       int i;
+
+                                       for (i = 0; i < *nwname; i++) {
+                                               errcode =
+                                                   p9pdu_readf(pdu,
+                                                               proto_version,
+                                                               "s",
+                                                               &(*wnames)[i]);
+                                               if (errcode)
+                                                       break;
+                                       }
+                               }
+
+                               if (errcode) {
+                                       if (*wnames) {
+                                               int i;
+
+                                               for (i = 0; i < *nwname; i++)
+                                                       kfree((*wnames)[i]);
+                                       }
+                                       kfree(*wnames);
+                                       *wnames = NULL;
+                               }
+                       }
+                       break;
+               case 'R':{
+                               uint16_t *nwqid = va_arg(ap, uint16_t *);
+                               struct p9_qid **wqids =
+                                   va_arg(ap, struct p9_qid **);
+
+                               *wqids = NULL;
+
+                               errcode =
+                                   p9pdu_readf(pdu, proto_version, "w", nwqid);
+                               if (!errcode) {
+                                       *wqids =
+                                           kmalloc(*nwqid *
+                                                   sizeof(struct p9_qid),
+                                                   GFP_NOFS);
+                                       if (*wqids == NULL)
+                                               errcode = -ENOMEM;
+                               }
+
+                               if (!errcode) {
+                                       int i;
+
+                                       for (i = 0; i < *nwqid; i++) {
+                                               errcode =
+                                                   p9pdu_readf(pdu,
+                                                               proto_version,
+                                                               "Q",
+                                                               &(*wqids)[i]);
+                                               if (errcode)
+                                                       break;
+                                       }
+                               }
+
+                               if (errcode) {
+                                       kfree(*wqids);
+                                       *wqids = NULL;
+                               }
+                       }
+                       break;
+               case 'A': {
+                               struct p9_stat_dotl *stbuf =
+                                   va_arg(ap, struct p9_stat_dotl *);
+
+                               memset(stbuf, 0, sizeof(struct p9_stat_dotl));
+                               errcode =
+                                   p9pdu_readf(pdu, proto_version,
+                                       "qQdugqqqqqqqqqqqqqqq",
+                                       &stbuf->st_result_mask,
+                                       &stbuf->qid,
+                                       &stbuf->st_mode,
+                                       &stbuf->st_uid, &stbuf->st_gid,
+                                       &stbuf->st_nlink,
+                                       &stbuf->st_rdev, &stbuf->st_size,
+                                       &stbuf->st_blksize, &stbuf->st_blocks,
+                                       &stbuf->st_atime_sec,
+                                       &stbuf->st_atime_nsec,
+                                       &stbuf->st_mtime_sec,
+                                       &stbuf->st_mtime_nsec,
+                                       &stbuf->st_ctime_sec,
+                                       &stbuf->st_ctime_nsec,
+                                       &stbuf->st_btime_sec,
+                                       &stbuf->st_btime_nsec,
+                                       &stbuf->st_gen,
+                                       &stbuf->st_data_version);
+                       }
+                       break;
+               case '?':
+                       if ((proto_version != p9_proto_2000u) &&
+                               (proto_version != p9_proto_2000L))
+                               return 0;
+                       break;
+               default:
+                       BUG();
+                       break;
+               }
+
+               if (errcode)
+                       break;
+       }
+
+       return errcode;
+}
+
+int
+p9pdu_vwritef(struct p9_fcall *pdu, int proto_version, const char *fmt,
+       va_list ap)
+{
+       const char *ptr;
+       int errcode = 0;
+
+       for (ptr = fmt; *ptr; ptr++) {
+               switch (*ptr) {
+               case 'b':{
+                               int8_t val = va_arg(ap, int);
+                               if (pdu_write(pdu, &val, sizeof(val)))
+                                       errcode = -EFAULT;
+                       }
+                       break;
+               case 'w':{
+                               __le16 val = cpu_to_le16(va_arg(ap, int));
+                               if (pdu_write(pdu, &val, sizeof(val)))
+                                       errcode = -EFAULT;
+                       }
+                       break;
+               case 'd':{
+                               __le32 val = cpu_to_le32(va_arg(ap, int32_t));
+                               if (pdu_write(pdu, &val, sizeof(val)))
+                                       errcode = -EFAULT;
+                       }
+                       break;
+               case 'q':{
+                               __le64 val = cpu_to_le64(va_arg(ap, int64_t));
+                               if (pdu_write(pdu, &val, sizeof(val)))
+                                       errcode = -EFAULT;
+                       }
+                       break;
+               case 's':{
+                               const char *sptr = va_arg(ap, const char *);
+                               uint16_t len = 0;
+                               if (sptr)
+                                       len = min_t(size_t, strlen(sptr),
+                                                               USHRT_MAX);
+
+                               errcode = p9pdu_writef(pdu, proto_version,
+                                                               "w", len);
+                               if (!errcode && pdu_write(pdu, sptr, len))
+                                       errcode = -EFAULT;
+                       }
+                       break;
+               case 'u': {
+                               kuid_t uid = va_arg(ap, kuid_t);
+                               __le32 val = cpu_to_le32(
+                                               from_kuid(&init_user_ns, uid));
+                               if (pdu_write(pdu, &val, sizeof(val)))
+                                       errcode = -EFAULT;
+                       } break;
+               case 'g': {
+                               kgid_t gid = va_arg(ap, kgid_t);
+                               __le32 val = cpu_to_le32(
+                                               from_kgid(&init_user_ns, gid));
+                               if (pdu_write(pdu, &val, sizeof(val)))
+                                       errcode = -EFAULT;
+                       } break;
+               case 'Q':{
+                               const struct p9_qid *qid =
+                                   va_arg(ap, const struct p9_qid *);
+                               errcode =
+                                   p9pdu_writef(pdu, proto_version, "bdq",
+                                                qid->type, qid->version,
+                                                qid->path);
+                       } break;
+               case 'S':{
+                               const struct p9_wstat *stbuf =
+                                   va_arg(ap, const struct p9_wstat *);
+                               errcode =
+                                   p9pdu_writef(pdu, proto_version,
+                                                "wwdQdddqssss?sugu",
+                                                stbuf->size, stbuf->type,
+                                                stbuf->dev, &stbuf->qid,
+                                                stbuf->mode, stbuf->atime,
+                                                stbuf->mtime, stbuf->length,
+                                                stbuf->name, stbuf->uid,
+                                                stbuf->gid, stbuf->muid,
+                                                stbuf->extension, stbuf->n_uid,
+                                                stbuf->n_gid, stbuf->n_muid);
+                       } break;
+               case 'V':{
+                               uint32_t count = va_arg(ap, uint32_t);
+                               struct iov_iter *from =
+                                               va_arg(ap, struct iov_iter *);
+                               errcode = p9pdu_writef(pdu, proto_version, "d",
+                                                                       count);
+                               if (!errcode && pdu_write_u(pdu, from, count))
+                                       errcode = -EFAULT;
+                       }
+                       break;
+               case 'T':{
+                               uint16_t nwname = va_arg(ap, int);
+                               const char **wnames = va_arg(ap, const char **);
+
+                               errcode = p9pdu_writef(pdu, proto_version, "w",
+                                                                       nwname);
+                               if (!errcode) {
+                                       int i;
+
+                                       for (i = 0; i < nwname; i++) {
+                                               errcode =
+                                                   p9pdu_writef(pdu,
+                                                               proto_version,
+                                                                "s",
+                                                                wnames[i]);
+                                               if (errcode)
+                                                       break;
+                                       }
+                               }
+                       }
+                       break;
+               case 'R':{
+                               uint16_t nwqid = va_arg(ap, int);
+                               struct p9_qid *wqids =
+                                   va_arg(ap, struct p9_qid *);
+
+                               errcode = p9pdu_writef(pdu, proto_version, "w",
+                                                                       nwqid);
+                               if (!errcode) {
+                                       int i;
+
+                                       for (i = 0; i < nwqid; i++) {
+                                               errcode =
+                                                   p9pdu_writef(pdu,
+                                                               proto_version,
+                                                                "Q",
+                                                                &wqids[i]);
+                                               if (errcode)
+                                                       break;
+                                       }
+                               }
+                       }
+                       break;
+               case 'I':{
+                               struct p9_iattr_dotl *p9attr = va_arg(ap,
+                                                       struct p9_iattr_dotl *);
+
+                               errcode = p9pdu_writef(pdu, proto_version,
+                                                       "ddugqqqqq",
+                                                       p9attr->valid,
+                                                       p9attr->mode,
+                                                       p9attr->uid,
+                                                       p9attr->gid,
+                                                       p9attr->size,
+                                                       p9attr->atime_sec,
+                                                       p9attr->atime_nsec,
+                                                       p9attr->mtime_sec,
+                                                       p9attr->mtime_nsec);
+                       }
+                       break;
+               case '?':
+                       if ((proto_version != p9_proto_2000u) &&
+                               (proto_version != p9_proto_2000L))
+                               return 0;
+                       break;
+               default:
+                       BUG();
+                       break;
+               }
+
+               if (errcode)
+                       break;
+       }
+
+       return errcode;
+}
+
+int p9pdu_readf(struct p9_fcall *pdu, int proto_version, const char *fmt, ...)
+{
+       va_list ap;
+       int ret;
+
+       va_start(ap, fmt);
+       ret = p9pdu_vreadf(pdu, proto_version, fmt, ap);
+       va_end(ap);
+
+       return ret;
+}
+
+static int
+p9pdu_writef(struct p9_fcall *pdu, int proto_version, const char *fmt, ...)
+{
+       va_list ap;
+       int ret;
+
+       va_start(ap, fmt);
+       ret = p9pdu_vwritef(pdu, proto_version, fmt, ap);
+       va_end(ap);
+
+       return ret;
+}
+
+int p9stat_read(struct p9_client *clnt, char *buf, int len, struct p9_wstat *st)
+{
+       struct p9_fcall fake_pdu;
+       int ret;
+
+       fake_pdu.size = len;
+       fake_pdu.capacity = len;
+       fake_pdu.sdata = buf;
+       fake_pdu.offset = 0;
+
+       ret = p9pdu_readf(&fake_pdu, clnt->proto_version, "S", st);
+       if (ret) {
+               p9_debug(P9_DEBUG_9P, "<<< p9stat_read failed: %d\n", ret);
+               trace_9p_protocol_dump(clnt, &fake_pdu);
+       }
+
+       return ret;
+}
+EXPORT_SYMBOL(p9stat_read);
+
+int p9pdu_prepare(struct p9_fcall *pdu, int16_t tag, int8_t type)
+{
+       pdu->id = type;
+       return p9pdu_writef(pdu, 0, "dbw", 0, type, tag);
+}
+
+int p9pdu_finalize(struct p9_client *clnt, struct p9_fcall *pdu)
+{
+       int size = pdu->size;
+       int err;
+
+       pdu->size = 0;
+       err = p9pdu_writef(pdu, 0, "d", size);
+       pdu->size = size;
+
+       trace_9p_protocol_dump(clnt, pdu);
+       p9_debug(P9_DEBUG_9P, ">>> size=%d type: %d tag: %d\n",
+                pdu->size, pdu->id, pdu->tag);
+
+       return err;
+}
+
+void p9pdu_reset(struct p9_fcall *pdu)
+{
+       pdu->offset = 0;
+       pdu->size = 0;
+}
+
+int p9dirent_read(struct p9_client *clnt, char *buf, int len,
+                 struct p9_dirent *dirent)
+{
+       struct p9_fcall fake_pdu;
+       int ret;
+       char *nameptr;
+
+       fake_pdu.size = len;
+       fake_pdu.capacity = len;
+       fake_pdu.sdata = buf;
+       fake_pdu.offset = 0;
+
+       ret = p9pdu_readf(&fake_pdu, clnt->proto_version, "Qqbs", &dirent->qid,
+                         &dirent->d_off, &dirent->d_type, &nameptr);
+       if (ret) {
+               p9_debug(P9_DEBUG_9P, "<<< p9dirent_read failed: %d\n", ret);
+               trace_9p_protocol_dump(clnt, &fake_pdu);
+               goto out;
+       }
+
+       strcpy(dirent->d_name, nameptr);
+       kfree(nameptr);
+
+out:
+       return fake_pdu.offset;
+}
+EXPORT_SYMBOL(p9dirent_read);