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-rw-r--r--net/9p/protocol.c457
1 files changed, 457 insertions, 0 deletions
diff --git a/net/9p/protocol.c b/net/9p/protocol.c
new file mode 100644
index 000000000000..43e98220e9a4
--- /dev/null
+++ b/net/9p/protocol.c
@@ -0,0 +1,457 @@
+/*
+ * 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 <net/9p/9p.h>
+#include <net/9p/client.h>
+#include "protocol.h"
+
+#ifndef MIN
+#define MIN(a, b) (((a) < (b)) ? (a) : (b))
+#endif
+
+#ifndef MAX
+#define MAX(a, b) (((a) > (b)) ? (a) : (b))
+#endif
+
+#ifndef offset_of
+#define offset_of(type, memb) \
+ ((unsigned long)(&((type *)0)->memb))
+#endif
+#ifndef container_of
+#define container_of(obj, type, memb) \
+ ((type *)(((char *)obj) - offset_of(type, memb)))
+#endif
+
+static int
+p9pdu_writef(struct p9_fcall *pdu, int optional, 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);
+
+static 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;
+}
+
+/*
+ b - int8_t
+ w - int16_t
+ d - int32_t
+ q - int64_t
+ s - string
+ 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)
+ ? - if optional = 1, continue parsing
+*/
+
+static int
+p9pdu_vreadf(struct p9_fcall *pdu, int optional, 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 *);
+ if (pdu_read(pdu, val, sizeof(*val))) {
+ errcode = -EFAULT;
+ break;
+ }
+ *val = cpu_to_le16(*val);
+ }
+ break;
+ case 'd':{
+ int32_t *val = va_arg(ap, int32_t *);
+ if (pdu_read(pdu, val, sizeof(*val))) {
+ errcode = -EFAULT;
+ break;
+ }
+ *val = cpu_to_le32(*val);
+ }
+ break;
+ case 'q':{
+ int64_t *val = va_arg(ap, int64_t *);
+ if (pdu_read(pdu, val, sizeof(*val))) {
+ errcode = -EFAULT;
+ break;
+ }
+ *val = cpu_to_le64(*val);
+ }
+ break;
+ case 's':{
+ char **ptr = va_arg(ap, char **);
+ int16_t len;
+ int size;
+
+ errcode = p9pdu_readf(pdu, optional, "w", &len);
+ if (errcode)
+ break;
+
+ size = MAX(len, 0);
+
+ *ptr = kmalloc(size + 1, GFP_KERNEL);
+ if (*ptr == NULL) {
+ errcode = -EFAULT;
+ break;
+ }
+ if (pdu_read(pdu, *ptr, size)) {
+ errcode = -EFAULT;
+ kfree(*ptr);
+ *ptr = NULL;
+ } else
+ (*ptr)[size] = 0;
+ }
+ break;
+ case 'Q':{
+ struct p9_qid *qid =
+ va_arg(ap, struct p9_qid *);
+
+ errcode = p9pdu_readf(pdu, optional, "bdq",
+ &qid->type, &qid->version,
+ &qid->path);
+ }
+ break;
+ case 'S':{
+ struct p9_wstat *stbuf =
+ va_arg(ap, struct p9_wstat *);
+
+ stbuf->extension = NULL;
+ stbuf->n_uid = stbuf->n_gid = stbuf->n_muid =
+ -1;
+
+ errcode =
+ p9pdu_readf(pdu, optional,
+ "wwdQdddqssss?sddd",
+ &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':{
+ int32_t *count = va_arg(ap, int32_t *);
+ void **data = va_arg(ap, void **);
+
+ errcode =
+ p9pdu_readf(pdu, optional, "d", count);
+ if (!errcode) {
+ *count =
+ MIN(*count,
+ pdu->size - pdu->offset);
+ *data = &pdu->sdata[pdu->offset];
+ }
+ }
+ break;
+ case 'T':{
+ int16_t *nwname = va_arg(ap, int16_t *);
+ char ***wnames = va_arg(ap, char ***);
+
+ errcode =
+ p9pdu_readf(pdu, optional, "w", nwname);
+ if (!errcode) {
+ *wnames =
+ kmalloc(sizeof(char *) * *nwname,
+ GFP_KERNEL);
+ if (!*wnames)
+ errcode = -ENOMEM;
+ }
+
+ if (!errcode) {
+ int i;
+
+ for (i = 0; i < *nwname; i++) {
+ errcode =
+ p9pdu_readf(pdu, optional,
+ "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':{
+ int16_t *nwqid = va_arg(ap, int16_t *);
+ struct p9_qid **wqids =
+ va_arg(ap, struct p9_qid **);
+
+ *wqids = NULL;
+
+ errcode =
+ p9pdu_readf(pdu, optional, "w", nwqid);
+ if (!errcode) {
+ *wqids =
+ kmalloc(*nwqid *
+ sizeof(struct p9_qid),
+ GFP_KERNEL);
+ if (*wqids == NULL)
+ errcode = -ENOMEM;
+ }
+
+ if (!errcode) {
+ int i;
+
+ for (i = 0; i < *nwqid; i++) {
+ errcode =
+ p9pdu_readf(pdu, optional,
+ "Q",
+ &(*wqids)[i]);
+ if (errcode)
+ break;
+ }
+ }
+
+ if (errcode) {
+ kfree(*wqids);
+ *wqids = NULL;
+ }
+ }
+ break;
+ case '?':
+ if (!optional)
+ return 0;
+ break;
+ default:
+ BUG();
+ break;
+ }
+
+ if (errcode)
+ break;
+ }
+
+ return errcode;
+}
+
+int
+p9pdu_vwritef(struct p9_fcall *pdu, int optional, 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':{
+ int16_t val = va_arg(ap, int);
+ if (pdu_write(pdu, &val, sizeof(val)))
+ errcode = -EFAULT;
+ }
+ break;
+ case 'd':{
+ int32_t val = va_arg(ap, int32_t);
+ if (pdu_write(pdu, &val, sizeof(val)))
+ errcode = -EFAULT;
+ }
+ break;
+ case 'q':{
+ int64_t val = va_arg(ap, int64_t);
+ if (pdu_write(pdu, &val, sizeof(val)))
+ errcode = -EFAULT;
+ }
+ break;
+ case 's':{
+ const char *ptr = va_arg(ap, const char *);
+ int16_t len = 0;
+
+ if (ptr)
+ len = MIN(strlen(ptr), USHORT_MAX);
+
+ errcode = p9pdu_writef(pdu, optional, "w", len);
+ if (!errcode && pdu_write(pdu, ptr, len))
+ errcode = -EFAULT;
+ }
+ break;
+ case 'Q':{
+ const struct p9_qid *qid =
+ va_arg(ap, const struct p9_qid *);
+ errcode =
+ p9pdu_writef(pdu, optional, "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, optional,
+ "wwdQdddqssss?sddd",
+ 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 'D':{
+ int32_t count = va_arg(ap, int32_t);
+ const void *data = va_arg(ap, const void *);
+
+ errcode =
+ p9pdu_writef(pdu, optional, "d", count);
+ if (!errcode && pdu_write(pdu, data, count))
+ errcode = -EFAULT;
+ }
+ break;
+ case 'T':{
+ int16_t nwname = va_arg(ap, int);
+ const char **wnames = va_arg(ap, const char **);
+
+ errcode =
+ p9pdu_writef(pdu, optional, "w", nwname);
+ if (!errcode) {
+ int i;
+
+ for (i = 0; i < nwname; i++) {
+ errcode =
+ p9pdu_writef(pdu, optional,
+ "s",
+ wnames[i]);
+ if (errcode)
+ break;
+ }
+ }
+ }
+ break;
+ case 'R':{
+ int16_t nwqid = va_arg(ap, int);
+ struct p9_qid *wqids =
+ va_arg(ap, struct p9_qid *);
+
+ errcode =
+ p9pdu_writef(pdu, optional, "w", nwqid);
+ if (!errcode) {
+ int i;
+
+ for (i = 0; i < nwqid; i++) {
+ errcode =
+ p9pdu_writef(pdu, optional,
+ "Q",
+ &wqids[i]);
+ if (errcode)
+ break;
+ }
+ }
+ }
+ break;
+ case '?':
+ if (!optional)
+ return 0;
+ break;
+ default:
+ BUG();
+ break;
+ }
+
+ if (errcode)
+ break;
+ }
+
+ return errcode;
+}
+
+int p9pdu_readf(struct p9_fcall *pdu, int optional, const char *fmt, ...)
+{
+ va_list ap;
+ int ret;
+
+ va_start(ap, fmt);
+ ret = p9pdu_vreadf(pdu, optional, fmt, ap);
+ va_end(ap);
+
+ return ret;
+}
+
+static int
+p9pdu_writef(struct p9_fcall *pdu, int optional, const char *fmt, ...)
+{
+ va_list ap;
+ int ret;
+
+ va_start(ap, fmt);
+ ret = p9pdu_vwritef(pdu, optional, fmt, ap);
+ va_end(ap);
+
+ return ret;
+}
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