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-rw-r--r--extras/mini-os/fs-front.c1129
-rw-r--r--extras/mini-os/include/fs.h51
-rw-r--r--extras/mini-os/include/types.h3
-rw-r--r--extras/mini-os/kernel.c7
-rw-r--r--tools/fs-back/Makefile40
-rw-r--r--tools/fs-back/fs-backend.c346
-rw-r--r--tools/fs-back/fs-backend.h86
-rw-r--r--tools/fs-back/fs-ops.c658
-rw-r--r--tools/fs-back/fs-xenbus.c180
-rw-r--r--xen/include/public/io/fsif.h181
10 files changed, 2681 insertions, 0 deletions
diff --git a/extras/mini-os/fs-front.c b/extras/mini-os/fs-front.c
new file mode 100644
index 0000000000..fcef1de2fb
--- /dev/null
+++ b/extras/mini-os/fs-front.c
@@ -0,0 +1,1129 @@
+/******************************************************************************
+ * fs-front.c
+ *
+ * Frontend driver for FS split device driver.
+ *
+ * Copyright (c) 2007, Grzegorz Milos, Sun Microsystems, Inc.
+ *
+ * Permission is hereby granted, free of charge, to any person obtaining a copy
+ * of this software and associated documentation files (the "Software"), to
+ * deal in the Software without restriction, including without limitation the
+ * rights to use, copy, modify, merge, publish, distribute, sublicense, and/or
+ * sell copies of the Software, and to permit persons to whom the Software is
+ * furnished to do so, subject to the following conditions:
+ *
+ * The above copyright notice and this permission notice shall be included in
+ * all copies or substantial portions of the Software.
+ *
+ * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
+ * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
+ * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
+ * AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
+ * LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING
+ * FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER
+ * DEALINGS IN THE SOFTWARE.
+ */
+
+#undef NDEBUG
+#include <os.h>
+#include <list.h>
+#include <xmalloc.h>
+#include <xenbus.h>
+#include <gnttab.h>
+#include <events.h>
+#include <xen/io/fsif.h>
+#include <fs.h>
+#include <sched.h>
+
+#define preempt_disable()
+#define preempt_enable()
+#define cmpxchg(p,o,n) synch_cmpxchg(p,o,n)
+
+
+#ifdef FS_DEBUG
+#define DEBUG(_f, _a...) \
+ printk("MINI_OS(file=fs-front.c, line=%d) " _f "\n", __LINE__, ## _a)
+#else
+#define DEBUG(_f, _a...) ((void)0)
+#endif
+
+
+struct fs_request;
+struct fs_import *fs_import;
+
+/******************************************************************************/
+/* RING REQUEST/RESPONSES HANDLING */
+/******************************************************************************/
+
+struct fs_request
+{
+ void *page;
+ grant_ref_t gref;
+ struct thread *thread; /* Thread blocked on this request */
+ struct fsif_response shadow_rsp; /* Response copy writen by the
+ interrupt handler */
+};
+
+/* Ring operations:
+ * FSIF ring is used differently to Linux-like split devices. This stems from
+ * the fact that no I/O request queue is present. The use of some of the macros
+ * defined in ring.h is not allowed, in particular:
+ * RING_PUSH_REQUESTS_AND_CHECK_NOTIFY cannot be used.
+ *
+ * The protocol used for FSIF ring is described below:
+ *
+ * In order to reserve a request the frontend:
+ * a) saves current frontend_ring->req_prod_pvt into a local variable
+ * b) checks that there are free request using the local req_prod_pvt
+ * c) tries to reserve the request using cmpxchg on frontend_ring->req_prod_pvt
+ * if cmpxchg fails, it means that someone reserved the request, start from
+ * a)
+ *
+ * In order to commit a request to the shared ring:
+ * a) cmpxchg shared_ring->req_prod from local req_prod_pvt to req_prod_pvt+1
+ * Loop if unsuccessful.
+ * NOTE: Request should be commited to the shared ring as quickly as possible,
+ * because otherwise other threads might busy loop trying to commit next
+ * requests. It also follows that preemption should be disabled, if
+ * possible, for the duration of the request construction.
+ */
+
+/* Number of free requests (for use on front side only). */
+#define FS_RING_FREE_REQUESTS(_r, _req_prod_pvt) \
+ (RING_SIZE(_r) - (_req_prod_pvt - (_r)->rsp_cons))
+
+
+
+static RING_IDX reserve_fsif_request(struct fs_import *import)
+{
+ RING_IDX idx;
+
+ down(&import->reqs_sem);
+ preempt_disable();
+again:
+ /* We will attempt to reserve slot idx */
+ idx = import->ring.req_prod_pvt;
+ ASSERT (FS_RING_FREE_REQUESTS(&import->ring, idx));
+ /* Attempt to reserve */
+ if(cmpxchg(&import->ring.req_prod_pvt, idx, idx+1) != idx)
+ goto again;
+
+ return idx;
+}
+
+static void commit_fsif_request(struct fs_import *import, RING_IDX idx)
+{
+ while(cmpxchg(&import->ring.sring->req_prod, idx, idx+1) != idx)
+ {
+ printk("Failed to commit a request: req_prod=%d, idx=%d\n",
+ import->ring.sring->req_prod, idx);
+ }
+ preempt_enable();
+
+ /* NOTE: we cannot do anything clever about rsp_event, to hold off
+ * notifications, because we don't know if we are a single request (in which
+ * case we have to notify always), or a part of a larger request group
+ * (when, in some cases, notification isn't required) */
+ notify_remote_via_evtchn(import->local_port);
+}
+
+
+
+static inline void add_id_to_freelist(unsigned int id,unsigned short* freelist)
+{
+ unsigned int old_id, new_id;
+
+again:
+ old_id = freelist[0];
+ /* Note: temporal inconsistency, since freelist[0] can be changed by someone
+ * else, but we are a sole owner of freelist[id], it's OK. */
+ freelist[id] = old_id;
+ new_id = id;
+ if(cmpxchg(&freelist[0], old_id, new_id) != old_id)
+ {
+ printk("Cmpxchg on freelist add failed.\n");
+ goto again;
+ }
+}
+
+/* always call reserve_fsif_request(import) before this, to protect from
+ * depletion. */
+static inline unsigned short get_id_from_freelist(unsigned short* freelist)
+{
+ unsigned int old_id, new_id;
+
+again:
+ old_id = freelist[0];
+ new_id = freelist[old_id];
+ if(cmpxchg(&freelist[0], old_id, new_id) != old_id)
+ {
+ printk("Cmpxchg on freelist remove failed.\n");
+ goto again;
+ }
+
+ return old_id;
+}
+
+/******************************************************************************/
+/* END OF RING REQUEST/RESPONSES HANDLING */
+/******************************************************************************/
+
+
+
+/******************************************************************************/
+/* INDIVIDUAL FILE OPERATIONS */
+/******************************************************************************/
+int fs_open(struct fs_import *import, char *file)
+{
+ struct fs_request *fsr;
+ unsigned short priv_req_id;
+ RING_IDX back_req_id;
+ struct fsif_request *req;
+ int fd;
+
+ /* Prepare request for the backend */
+ back_req_id = reserve_fsif_request(import);
+ DEBUG("Backend request id=%d, gref=%d\n", back_req_id, fsr->gref);
+
+ /* Prepare our private request structure */
+ priv_req_id = get_id_from_freelist(import->freelist);
+ DEBUG("Request id for fs_open call is: %d\n", priv_req_id);
+ fsr = &import->requests[priv_req_id];
+ fsr->thread = current;
+ sprintf(fsr->page, "%s", file);
+
+ req = RING_GET_REQUEST(&import->ring, back_req_id);
+ req->type = REQ_FILE_OPEN;
+ req->id = priv_req_id;
+ req->u.fopen.gref = fsr->gref;
+
+ /* Set blocked flag before commiting the request, thus avoiding missed
+ * response race */
+ block(current);
+ commit_fsif_request(import, back_req_id);
+ schedule();
+
+ /* Read the response */
+ fd = (int)fsr->shadow_rsp.ret_val;
+ DEBUG("The following FD returned: %d\n", fd);
+ add_id_to_freelist(priv_req_id, import->freelist);
+
+ return fd;
+}
+
+int fs_close(struct fs_import *import, int fd)
+{
+ struct fs_request *fsr;
+ unsigned short priv_req_id;
+ RING_IDX back_req_id;
+ struct fsif_request *req;
+ int ret;
+
+ /* Prepare request for the backend */
+ back_req_id = reserve_fsif_request(import);
+ DEBUG("Backend request id=%d, gref=%d\n", back_req_id, fsr->gref);
+
+ /* Prepare our private request structure */
+ priv_req_id = get_id_from_freelist(import->freelist);
+ DEBUG("Request id for fs_close call is: %d\n", priv_req_id);
+ fsr = &import->requests[priv_req_id];
+ fsr->thread = current;
+
+ req = RING_GET_REQUEST(&import->ring, back_req_id);
+ req->type = REQ_FILE_CLOSE;
+ req->id = priv_req_id;
+ req->u.fclose.fd = fd;
+
+ /* Set blocked flag before commiting the request, thus avoiding missed
+ * response race */
+ block(current);
+ commit_fsif_request(import, back_req_id);
+ schedule();
+
+ /* Read the response */
+ ret = (int)fsr->shadow_rsp.ret_val;
+ DEBUG("Close returned: %d\n", ret);
+ add_id_to_freelist(priv_req_id, import->freelist);
+
+ return ret;
+}
+
+ssize_t fs_read(struct fs_import *import, int fd, void *buf,
+ ssize_t len, ssize_t offset)
+{
+ struct fs_request *fsr;
+ unsigned short priv_req_id;
+ RING_IDX back_req_id;
+ struct fsif_request *req;
+ ssize_t ret;
+
+ BUG_ON(len > PAGE_SIZE);
+
+ /* Prepare request for the backend */
+ back_req_id = reserve_fsif_request(import);
+ DEBUG("Backend request id=%d, gref=%d\n", back_req_id, fsr->gref);
+
+ /* Prepare our private request structure */
+ priv_req_id = get_id_from_freelist(import->freelist);
+ DEBUG("Request id for fs_read call is: %d\n", priv_req_id);
+ fsr = &import->requests[priv_req_id];
+ fsr->thread = current;
+ memset(fsr->page, 0, PAGE_SIZE);
+
+ req = RING_GET_REQUEST(&import->ring, back_req_id);
+ req->type = REQ_FILE_READ;
+ req->id = priv_req_id;
+ req->u.fread.fd = fd;
+ req->u.fread.gref = fsr->gref;
+ req->u.fread.len = len;
+ req->u.fread.offset = offset;
+
+ /* Set blocked flag before commiting the request, thus avoiding missed
+ * response race */
+ block(current);
+ commit_fsif_request(import, back_req_id);
+ schedule();
+
+ /* Read the response */
+ ret = (ssize_t)fsr->shadow_rsp.ret_val;
+ DEBUG("The following ret value returned %d\n", ret);
+ if(ret > 0)
+ memcpy(buf, fsr->page, ret);
+ add_id_to_freelist(priv_req_id, import->freelist);
+
+ return ret;
+}
+
+ssize_t fs_write(struct fs_import *import, int fd, void *buf,
+ ssize_t len, ssize_t offset)
+{
+ struct fs_request *fsr;
+ unsigned short priv_req_id;
+ RING_IDX back_req_id;
+ struct fsif_request *req;
+ ssize_t ret;
+
+ BUG_ON(len > PAGE_SIZE);
+
+ /* Prepare request for the backend */
+ back_req_id = reserve_fsif_request(import);
+ DEBUG("Backend request id=%d, gref=%d\n", back_req_id, fsr->gref);
+
+ /* Prepare our private request structure */
+ priv_req_id = get_id_from_freelist(import->freelist);
+ DEBUG("Request id for fs_read call is: %d\n", priv_req_id);
+ fsr = &import->requests[priv_req_id];
+ fsr->thread = current;
+ memcpy(fsr->page, buf, len);
+ BUG_ON(len > PAGE_SIZE);
+ memset((char *)fsr->page + len, 0, PAGE_SIZE - len);
+
+ req = RING_GET_REQUEST(&import->ring, back_req_id);
+ req->type = REQ_FILE_WRITE;
+ req->id = priv_req_id;
+ req->u.fwrite.fd = fd;
+ req->u.fwrite.gref = fsr->gref;
+ req->u.fwrite.len = len;
+ req->u.fwrite.offset = offset;
+
+ /* Set blocked flag before commiting the request, thus avoiding missed
+ * response race */
+ block(current);
+ commit_fsif_request(import, back_req_id);
+ schedule();
+
+ /* Read the response */
+ ret = (ssize_t)fsr->shadow_rsp.ret_val;
+ DEBUG("The following ret value returned %d\n", ret);
+ add_id_to_freelist(priv_req_id, import->freelist);
+
+ return ret;
+}
+
+int fs_stat(struct fs_import *import,
+ int fd,
+ struct fsif_stat_response *stat)
+{
+ struct fs_request *fsr;
+ unsigned short priv_req_id;
+ RING_IDX back_req_id;
+ struct fsif_request *req;
+ int ret;
+
+ /* Prepare request for the backend */
+ back_req_id = reserve_fsif_request(import);
+ DEBUG("Backend request id=%d, gref=%d\n", back_req_id, fsr->gref);
+
+ /* Prepare our private request structure */
+ priv_req_id = get_id_from_freelist(import->freelist);
+ DEBUG("Request id for fs_stat call is: %d\n", priv_req_id);
+ fsr = &import->requests[priv_req_id];
+ fsr->thread = current;
+ memset(fsr->page, 0, PAGE_SIZE);
+
+ req = RING_GET_REQUEST(&import->ring, back_req_id);
+ req->type = REQ_STAT;
+ req->id = priv_req_id;
+ req->u.fstat.fd = fd;
+ req->u.fstat.gref = fsr->gref;
+
+ /* Set blocked flag before commiting the request, thus avoiding missed
+ * response race */
+ block(current);
+ commit_fsif_request(import, back_req_id);
+ schedule();
+
+ /* Read the response */
+ ret = (int)fsr->shadow_rsp.ret_val;
+ DEBUG("Following ret from fstat: %d\n", ret);
+ memcpy(stat, fsr->page, sizeof(struct fsif_stat_response));
+ add_id_to_freelist(priv_req_id, import->freelist);
+
+ return ret;
+}
+
+int fs_truncate(struct fs_import *import,
+ int fd,
+ int64_t length)
+{
+ struct fs_request *fsr;
+ unsigned short priv_req_id;
+ RING_IDX back_req_id;
+ struct fsif_request *req;
+ int ret;
+
+ /* Prepare request for the backend */
+ back_req_id = reserve_fsif_request(import);
+ DEBUG("Backend request id=%d, gref=%d\n", back_req_id, fsr->gref);
+
+ /* Prepare our private request structure */
+ priv_req_id = get_id_from_freelist(import->freelist);
+ DEBUG("Request id for fs_truncate call is: %d\n", priv_req_id);
+ fsr = &import->requests[priv_req_id];
+ fsr->thread = current;
+
+ req = RING_GET_REQUEST(&import->ring, back_req_id);
+ req->type = REQ_FILE_TRUNCATE;
+ req->id = priv_req_id;
+ req->u.ftruncate.fd = fd;
+ req->u.ftruncate.length = length;
+
+ /* Set blocked flag before commiting the request, thus avoiding missed
+ * response race */
+ block(current);
+ commit_fsif_request(import, back_req_id);
+ schedule();
+
+ /* Read the response */
+ ret = (int)fsr->shadow_rsp.ret_val;
+ DEBUG("Following ret from ftruncate: %d\n", ret);
+ add_id_to_freelist(priv_req_id, import->freelist);
+
+ return ret;
+}
+
+int fs_remove(struct fs_import *import, char *file)
+{
+ struct fs_request *fsr;
+ unsigned short priv_req_id;
+ RING_IDX back_req_id;
+ struct fsif_request *req;
+ int ret;
+
+ /* Prepare request for the backend */
+ back_req_id = reserve_fsif_request(import);
+ DEBUG("Backend request id=%d, gref=%d\n", back_req_id, fsr->gref);
+
+ /* Prepare our private request structure */
+ priv_req_id = get_id_from_freelist(import->freelist);
+ DEBUG("Request id for fs_open call is: %d\n", priv_req_id);
+ fsr = &import->requests[priv_req_id];
+ fsr->thread = current;
+ sprintf(fsr->page, "%s", file);
+
+ req = RING_GET_REQUEST(&import->ring, back_req_id);
+ req->type = REQ_REMOVE;
+ req->id = priv_req_id;
+ req->u.fremove.gref = fsr->gref;
+
+ /* Set blocked flag before commiting the request, thus avoiding missed
+ * response race */
+ block(current);
+ commit_fsif_request(import, back_req_id);
+ schedule();
+
+ /* Read the response */
+ ret = (int)fsr->shadow_rsp.ret_val;
+ DEBUG("The following ret: %d\n", ret);
+ add_id_to_freelist(priv_req_id, import->freelist);
+
+ return ret;
+}
+
+
+int fs_rename(struct fs_import *import,
+ char *old_file_name,
+ char *new_file_name)
+{
+ struct fs_request *fsr;
+ unsigned short priv_req_id;
+ RING_IDX back_req_id;
+ struct fsif_request *req;
+ int ret;
+ char old_header[] = "old: ";
+ char new_header[] = "new: ";
+
+ /* Prepare request for the backend */
+ back_req_id = reserve_fsif_request(import);
+ DEBUG("Backend request id=%d, gref=%d\n", back_req_id, fsr->gref);
+
+ /* Prepare our private request structure */
+ priv_req_id = get_id_from_freelist(import->freelist);
+ DEBUG("Request id for fs_open call is: %d\n", priv_req_id);
+ fsr = &import->requests[priv_req_id];
+ fsr->thread = current;
+ sprintf(fsr->page, "%s%s%c%s%s",
+ old_header, old_file_name, '\0', new_header, new_file_name);
+
+ req = RING_GET_REQUEST(&import->ring, back_req_id);
+ req->type = REQ_RENAME;
+ req->id = priv_req_id;
+ req->u.frename.gref = fsr->gref;
+ req->u.frename.old_name_offset = strlen(old_header);
+ req->u.frename.new_name_offset = strlen(old_header) +
+ strlen(old_file_name) +
+ strlen(new_header) +
+ 1 /* Accouning for the additional
+ end of string character */;
+
+ /* Set blocked flag before commiting the request, thus avoiding missed
+ * response race */
+ block(current);
+ commit_fsif_request(import, back_req_id);
+ schedule();
+
+ /* Read the response */
+ ret = (int)fsr->shadow_rsp.ret_val;
+ DEBUG("The following ret: %d\n", ret);
+ add_id_to_freelist(priv_req_id, import->freelist);
+
+ return ret;
+}
+
+int fs_create(struct fs_import *import, char *name,
+ int8_t directory, int32_t mode)
+{
+ struct fs_request *fsr;
+ unsigned short priv_req_id;
+ RING_IDX back_req_id;
+ struct fsif_request *req;
+ int ret;
+
+ /* Prepare request for the backend */
+ back_req_id = reserve_fsif_request(import);
+ DEBUG("Backend request id=%d, gref=%d\n", back_req_id, fsr->gref);
+
+ /* Prepare our private request structure */
+ priv_req_id = get_id_from_freelist(import->freelist);
+ DEBUG("Request id for fs_create call is: %d\n", priv_req_id);
+ fsr = &import->requests[priv_req_id];
+ fsr->thread = current;
+ sprintf(fsr->page, "%s", name);
+
+ req = RING_GET_REQUEST(&import->ring, back_req_id);
+ req->type = REQ_CREATE;
+ req->id = priv_req_id;
+ req->u.fcreate.gref = fsr->gref;
+ req->u.fcreate.directory = directory;
+ req->u.fcreate.mode = mode;
+
+ /* Set blocked flag before commiting the request, thus avoiding missed
+ * response race */
+ block(current);
+ commit_fsif_request(import, back_req_id);
+ schedule();
+
+ /* Read the response */
+ ret = (int)fsr->shadow_rsp.ret_val;
+ DEBUG("The following ret: %d\n", ret);
+ add_id_to_freelist(priv_req_id, import->freelist);
+
+ return ret;
+}
+
+char** fs_list(struct fs_import *import, char *name,
+ int32_t offset, int32_t *nr_files, int *has_more)
+{
+ struct fs_request *fsr;
+ unsigned short priv_req_id;
+ RING_IDX back_req_id;
+ struct fsif_request *req;
+ char **files, *current_file;
+ int i;
+
+ DEBUG("Different masks: NR_FILES=(%llx, %d), ERROR=(%llx, %d), HAS_MORE(%llx, %d)\n",
+ NR_FILES_MASK, NR_FILES_SHIFT, ERROR_MASK, ERROR_SHIFT, HAS_MORE_FLAG, HAS_MORE_SHIFT);
+
+ /* Prepare request for the backend */
+ back_req_id = reserve_fsif_request(import);
+ DEBUG("Backend request id=%d, gref=%d\n", back_req_id, fsr->gref);
+
+ /* Prepare our private request structure */
+ priv_req_id = get_id_from_freelist(import->freelist);
+ DEBUG("Request id for fs_list call is: %d\n", priv_req_id);
+ fsr = &import->requests[priv_req_id];
+ fsr->thread = current;
+ sprintf(fsr->page, "%s", name);
+
+ req = RING_GET_REQUEST(&import->ring, back_req_id);
+ req->type = REQ_DIR_LIST;
+ req->id = priv_req_id;
+ req->u.flist.gref = fsr->gref;
+ req->u.flist.offset = offset;
+
+ /* Set blocked flag before commiting the request, thus avoiding missed
+ * response race */
+ block(current);
+ commit_fsif_request(import, back_req_id);
+ schedule();
+
+ /* Read the response */
+ *nr_files = (fsr->shadow_rsp.ret_val & NR_FILES_MASK) >> NR_FILES_SHIFT;
+ files = NULL;
+ if(*nr_files <= 0) goto exit;
+ files = malloc(sizeof(char*) * (*nr_files));
+ current_file = fsr->page;
+ for(i=0; i<*nr_files; i++)
+ {
+ files[i] = strdup(current_file);
+ current_file += strlen(current_file) + 1;
+ }
+ if(has_more != NULL)
+ *has_more = fsr->shadow_rsp.ret_val & HAS_MORE_FLAG;
+ add_id_to_freelist(priv_req_id, import->freelist);
+exit:
+ return files;
+}
+
+int fs_chmod(struct fs_import *import, int fd, int32_t mode)
+{
+ struct fs_request *fsr;
+ unsigned short priv_req_id;
+ RING_IDX back_req_id;
+ struct fsif_request *req;
+ int ret;
+
+ /* Prepare request for the backend */
+ back_req_id = reserve_fsif_request(import);
+ DEBUG("Backend request id=%d, gref=%d\n", back_req_id, fsr->gref);
+
+ /* Prepare our private request structure */
+ priv_req_id = get_id_from_freelist(import->freelist);
+ DEBUG("Request id for fs_chmod call is: %d\n", priv_req_id);
+ fsr = &import->requests[priv_req_id];
+ fsr->thread = current;
+
+ req = RING_GET_REQUEST(&import->ring, back_req_id);
+ req->type = REQ_CHMOD;
+ req->id = priv_req_id;
+ req->u.fchmod.fd = fd;
+ req->u.fchmod.mode = mode;
+
+ /* Set blocked flag before commiting the request, thus avoiding missed
+ * response race */
+ block(current);
+ commit_fsif_request(import, back_req_id);
+ schedule();
+
+ /* Read the response */
+ ret = (int)fsr->shadow_rsp.ret_val;
+ DEBUG("The following returned: %d\n", ret);
+ add_id_to_freelist(priv_req_id, import->freelist);
+
+ return ret;
+}
+
+int64_t fs_space(struct fs_import *import, char *location)
+{
+ struct fs_request *fsr;
+ unsigned short priv_req_id;
+ RING_IDX back_req_id;
+ struct fsif_request *req;
+ int64_t ret;
+
+ /* Prepare request for the backend */
+ back_req_id = reserve_fsif_request(import);
+ DEBUG("Backend request id=%d, gref=%d\n", back_req_id, fsr->gref);
+
+ /* Prepare our private request structure */
+ priv_req_id = get_id_from_freelist(import->freelist);
+ DEBUG("Request id for fs_space is: %d\n", priv_req_id);
+ fsr = &import->requests[priv_req_id];
+ fsr->thread = current;
+ sprintf(fsr->page, "%s", location);
+
+ req = RING_GET_REQUEST(&import->ring, back_req_id);
+ req->type = REQ_FS_SPACE;
+ req->id = priv_req_id;
+ req->u.fspace.gref = fsr->gref;
+
+ /* Set blocked flag before commiting the request, thus avoiding missed
+ * response race */
+ block(current);
+ commit_fsif_request(import, back_req_id);
+ schedule();
+
+ /* Read the response */
+ ret = (int64_t)fsr->shadow_rsp.ret_val;
+ DEBUG("The following returned: %lld\n", ret);
+ add_id_to_freelist(priv_req_id, import->freelist);
+
+ return ret;
+}
+
+int fs_sync(struct fs_import *import, int fd)
+{
+ struct fs_request *fsr;
+ unsigned short priv_req_id;
+ RING_IDX back_req_id;
+ struct fsif_request *req;
+ int ret;
+
+ /* Prepare request for the backend */
+ back_req_id = reserve_fsif_request(import);
+ DEBUG("Backend request id=%d, gref=%d\n", back_req_id, fsr->gref);
+
+ /* Prepare our private request structure */
+ priv_req_id = get_id_from_freelist(import->freelist);
+ DEBUG("Request id for fs_sync call is: %d\n", priv_req_id);
+ fsr = &import->requests[priv_req_id];
+ fsr->thread = current;
+
+ req = RING_GET_REQUEST(&import->ring, back_req_id);
+ req->type = REQ_FILE_SYNC;
+ req->id = priv_req_id;
+ req->u.fsync.fd = fd;
+
+ /* Set blocked flag before commiting the request, thus avoiding missed
+ * response race */
+ block(current);
+ commit_fsif_request(import, back_req_id);
+ schedule();
+
+ /* Read the response */
+ ret = (int)fsr->shadow_rsp.ret_val;
+ DEBUG("Close returned: %d\n", ret);
+ add_id_to_freelist(priv_req_id, import->freelist);
+
+ return ret;
+}
+
+
+/******************************************************************************/
+/* END OF INDIVIDUAL FILE OPERATIONS */
+/******************************************************************************/
+
+
+static void fsfront_handler(evtchn_port_t port, struct pt_regs *regs, void *data)
+{
+ struct fs_import *import = (struct fs_import*)data;
+ static int in_irq = 0;
+ RING_IDX cons, rp;
+ int more;
+
+ /* Check for non-reentrance */
+ BUG_ON(in_irq);
+ in_irq = 1;
+
+ DEBUG("Event from import [%d:%d].\n", import->dom_id, import->export_id);
+moretodo:
+ rp = import->ring.sring->req_prod;
+ rmb(); /* Ensure we see queued responses up to 'rp'. */
+ cons = import->ring.rsp_cons;
+ while (cons != rp)
+ {
+ struct fsif_response *rsp;
+ struct fs_request *req;
+
+ rsp = RING_GET_RESPONSE(&import->ring, cons);
+ DEBUG("Response at idx=%d to request id=%d, ret_val=%lx\n",
+ import->ring.rsp_cons, rsp->id, rsp->ret_val);
+ req = &import->requests[rsp->id];
+ memcpy(&req->shadow_rsp, rsp, sizeof(struct fsif_response));
+ DEBUG("Waking up: %s\n", req->thread->name);
+ wake(req->thread);
+
+ cons++;
+ up(&import->reqs_sem);
+ }
+
+ import->ring.rsp_cons = rp;
+ RING_FINAL_CHECK_FOR_RESPONSES(&import->ring, more);
+ if(more) goto moretodo;
+
+ in_irq = 0;
+}
+
+/* Small utility function to figure out our domain id */
+static domid_t get_self_id(void)
+{
+ char *dom_id;
+ domid_t ret;
+
+ BUG_ON(xenbus_read(XBT_NIL, "domid", &dom_id));
+ sscanf(dom_id, "%d", &ret);
+
+ return ret;
+}
+
+static void alloc_request_table(struct fs_import *import)
+{
+ struct fs_request *requests;
+ int i;
+
+ BUG_ON(import->nr_entries <= 0);
+ printk("Allocating request array for import %d, nr_entries = %d.\n",
+ import->import_id, import->nr_entries);
+ requests = xmalloc_array(struct fs_request, import->nr_entries);
+ import->freelist = xmalloc_array(unsigned short, import->nr_entries);
+ memset(import->freelist, 0, sizeof(unsigned short) * import->nr_entries);
+ for(i=0; i<import->nr_entries; i++)
+ {
+ /* TODO: that's a lot of memory */
+ requests[i].page = (void *)alloc_page();
+ requests[i].gref = gnttab_grant_access(import->dom_id,
+ virt_to_mfn(requests[i].page),
+ 0);
+ //printk(" ===>> Page=%lx, gref=%d, mfn=%lx\n", requests[i].page, requests[i].gref, virt_to_mfn(requests[i].page));
+ add_id_to_freelist(i, import->freelist);
+ }
+ import->requests = requests;
+}
+
+
+/******************************************************************************/
+/* FS TESTS */
+/******************************************************************************/
+
+
+void test_fs_import(void *data)
+{
+ struct fs_import *import = (struct fs_import *)data;
+ int ret, fd, i;
+ int32_t nr_files;
+ char buffer[1024];
+ ssize_t offset;
+ char **files;
+ long ret64;
+
+ /* Sleep for 1s and then try to open a file */
+ sleep(1000);
+ ret = fs_create(import, "mini-os-created-directory", 1, 0777);
+ printk("Directory create: %d\n", ret);
+
+ ret = fs_create(import, "mini-os-created-directory/mini-os-created-file", 0, 0666);
+ printk("File create: %d\n", ret);
+
+ fd = fs_open(import, "mini-os-created-directory/mini-os-created-file");
+ printk("File descriptor: %d\n", fd);
+ if(fd < 0) return;
+
+ offset = 0;
+ for(i=0; i<10; i++)
+ {
+ sprintf(buffer, "Current time is: %lld\n", NOW());
+ ret = fs_write(import, fd, buffer, strlen(buffer), offset);
+ printk("Writen current time (%d)\n", ret);
+ if(ret < 0)
+ return;
+ offset += ret;
+ }
+
+ ret = fs_close(import, fd);
+ printk("Closed fd: %d, ret=%d\n", fd, ret);
+
+ printk("Listing files in /\n");
+ files = fs_list(import, "/", 0, &nr_files, NULL);
+ for(i=0; i<nr_files; i++)
+ printk(" files[%d] = %s\n", i, files[i]);
+
+ ret64 = fs_space(import, "/");
+ printk("Free space: %lld (=%lld Mb)\n", ret64, (ret64 >> 20));
+
+}
+
+#if 0
+// char *content = (char *)alloc_page();
+ int fd, ret;
+// int read;
+ char write_string[] = "\"test data written from minios\"";
+ struct fsif_stat_response stat;
+ char **files;
+ int32_t nr_files, i;
+ int64_t ret64;
+
+
+ fd = fs_open(import, "test-export-file");
+// read = fs_read(import, fd, content, PAGE_SIZE, 0);
+// printk("Read: %d bytes\n", read);
+// content[read] = '\0';
+// printk("Value: %s\n", content);
+ ret = fs_write(import, fd, write_string, strlen(write_string), 0);
+ printk("Ret after write: %d\n", ret);
+ ret = fs_stat(import, fd, &stat);
+ printk("Ret after stat: %d\n", ret);
+ printk(" st_mode=%o\n", stat.stat_mode);
+ printk(" st_uid =%d\n", stat.stat_uid);
+ printk(" st_gid =%d\n", stat.stat_gid);
+ printk(" st_size=%ld\n", stat.stat_size);
+ printk(" st_atime=%ld\n", stat.stat_atime);
+ printk(" st_mtime=%ld\n", stat.stat_mtime);
+ printk(" st_ctime=%ld\n", stat.stat_ctime);
+ ret = fs_truncate(import, fd, 30);
+ printk("Ret after truncate: %d\n", ret);
+ ret = fs_remove(import, "test-to-remove/test-file");
+ printk("Ret after remove: %d\n", ret);
+ ret = fs_remove(import, "test-to-remove");
+ printk("Ret after remove: %d\n", ret);
+ ret = fs_chmod(import, fd, 0700);
+ printk("Ret after chmod: %d\n", ret);
+ ret = fs_sync(import, fd);
+ printk("Ret after sync: %d\n", ret);
+ ret = fs_close(import, fd);
+ //ret = fs_rename(import, "test-export-file", "renamed-test-export-file");
+ //printk("Ret after rename: %d\n", ret);
+ ret = fs_create(import, "created-dir", 1, 0777);
+ printk("Ret after dir create: %d\n", ret);
+ ret = fs_create(import, "created-dir/created-file", 0, 0777);
+ printk("Ret after file create: %d\n", ret);
+ files = fs_list(import, "/", 15, &nr_files, NULL);
+ for(i=0; i<nr_files; i++)
+ printk(" files[%d] = %s\n", i, files[i]);
+ ret64 = fs_space(import, "created-dir");
+ printk("Ret after space: %lld\n", ret64);
+
+#endif
+
+
+/******************************************************************************/
+/* END OF FS TESTS */
+/******************************************************************************/
+
+static int init_fs_import(struct fs_import *import)
+{
+ char *err;
+ xenbus_transaction_t xbt;
+ char nodename[1024], r_nodename[1024], token[128], *message = NULL;
+ struct fsif_sring *sring;
+ int retry = 0;
+ domid_t self_id;
+
+ printk("Initialising FS fortend to backend dom %d\n", import->dom_id);
+ /* Allocate page for the shared ring */
+ sring = (struct fsif_sring*) alloc_page();
+ memset(sring, 0, PAGE_SIZE);
+
+ /* Init the shared ring */
+ SHARED_RING_INIT(sring);
+
+ /* Init private frontend ring */
+ FRONT_RING_INIT(&import->ring, sring, PAGE_SIZE);
+ import->nr_entries = import->ring.nr_ents;
+
+ /* Allocate table of requests */
+ alloc_request_table(import);
+ init_SEMAPHORE(&import->reqs_sem, import->nr_entries);
+
+ /* Grant access to the shared ring */
+ import->gnt_ref = gnttab_grant_access(import->dom_id, virt_to_mfn(sring), 0);
+
+ /* Allocate event channel */
+ BUG_ON(evtchn_alloc_unbound(import->dom_id,
+ fsfront_handler,
+ //ANY_CPU,
+ import,
+ &import->local_port));
+
+
+ self_id = get_self_id();
+ /* Write the frontend info to a node in our Xenbus */
+ sprintf(nodename, "/local/domain/%d/device/vfs/%d",
+ self_id, import->import_id);
+
+again:
+ err = xenbus_transaction_start(&xbt);
+ if (err) {
+ printk("starting transaction\n");
+ }
+
+ err = xenbus_printf(xbt,
+ nodename,
+ "ring-ref",
+ "%u",
+ import->gnt_ref);
+ if (err) {
+ message = "writing ring-ref";
+ goto abort_transaction;
+ }
+
+ err = xenbus_printf(xbt,
+ nodename,
+ "event-channel",
+ "%u",
+ import->local_port);
+ if (err) {
+ message = "writing event-channel";
+ goto abort_transaction;
+ }
+
+ err = xenbus_printf(xbt, nodename, "state", STATE_READY, 0xdeadbeef);
+
+
+ err = xenbus_transaction_end(xbt, 0, &retry);
+ if (retry) {
+ goto again;
+ printk("completing transaction\n");
+ }
+
+ /* Now, when our node is prepared we write request in the exporting domain
+ * */
+ printk("Our own id is %d\n", self_id);
+ sprintf(r_nodename,
+ "/local/domain/%d/backend/vfs/exports/requests/%d/%d/frontend",
+ import->dom_id, self_id, import->export_id);
+ BUG_ON(xenbus_write(XBT_NIL, r_nodename, nodename));
+
+ goto done;
+
+abort_transaction:
+ xenbus_transaction_end(xbt, 1, &retry);
+
+done:
+
+#define WAIT_PERIOD 10 /* Wait period in ms */
+#define MAX_WAIT 10 /* Max number of WAIT_PERIODs */
+ import->backend = NULL;
+ sprintf(r_nodename, "%s/backend", nodename);
+
+ for(retry = MAX_WAIT; retry > 0; retry--)
+ {
+ xenbus_read(XBT_NIL, r_nodename, &import->backend);
+ if(import->backend)
+ {
+ printk("Backend found at %s\n", import->backend);
+ break;
+ }
+ sleep(WAIT_PERIOD);
+ }
+
+ if(!import->backend)
+ {
+ printk("No backend available.\n");
+ /* TODO - cleanup datastructures/xenbus */
+ return 0;
+ }
+ sprintf(r_nodename, "%s/state", import->backend);
+ sprintf(token, "fs-front-%d", import->import_id);
+ /* The token will not be unique if multiple imports are inited */
+ xenbus_watch_path(XBT_NIL, r_nodename/*, token*/);
+ xenbus_wait_for_value(/*token,*/ r_nodename, STATE_READY);
+ printk("Backend ready.\n");
+
+ //create_thread("fs-tester", test_fs_import, import);
+
+ return 1;
+}
+
+static void add_export(struct list_head *exports, unsigned int domid)
+{
+ char node[1024], **exports_list = NULL, *ret_msg;
+ int j = 0;
+ static int import_id = 0;
+
+ sprintf(node, "/local/domain/%d/backend/vfs/exports", domid);
+ ret_msg = xenbus_ls(XBT_NIL, node, &exports_list);
+ if (ret_msg && strcmp(ret_msg, "ENOENT"))
+ printk("couldn't read %s: %s\n", node, ret_msg);
+ while(exports_list && exports_list[j])
+ {
+ struct fs_import *import;
+ int export_id = -1;
+
+ sscanf(exports_list[j], "%d", &export_id);
+ if(export_id >= 0)
+ {
+ import = xmalloc(struct fs_import);
+ import->dom_id = domid;
+ import->export_id = export_id;
+ import->import_id = import_id++;
+ INIT_LIST_HEAD(&import->list);
+ list_add(&import->list, exports);
+ }
+ free(exports_list[j]);
+ j++;
+ }
+ if(exports_list)
+ free(exports_list);
+ if(ret_msg)
+ free(ret_msg);
+}
+
+#if 0
+static struct list_head* probe_exports(void)
+{
+ struct list_head *exports;
+ char **node_list = NULL, *msg = NULL;
+ int i = 0;
+
+ exports = xmalloc(struct list_head);
+ INIT_LIST_HEAD(exports);
+
+ msg = xenbus_ls(XBT_NIL, "/local/domain", &node_list);
+ if(msg)
+ {
+ printk("Could not list VFS exports (%s).\n", msg);
+ goto exit;
+ }
+
+ while(node_list[i])
+ {
+ add_export(exports, atoi(node_list[i]));
+ free(node_list[i]);
+ i++;
+ }
+
+exit:
+ if(msg)
+ free(msg);
+ if(node_list)
+ free(node_list);
+ return exports;
+}
+#endif
+
+LIST_HEAD(exports);
+
+void init_fs_frontend(void)
+{
+ struct list_head *entry;
+ struct fs_import *import = NULL;
+ printk("Initing FS fronend(s).\n");
+
+ //exports = probe_exports();
+ add_export(&exports, 0);
+ list_for_each(entry, &exports)
+ {
+ import = list_entry(entry, struct fs_import, list);
+ printk("FS export [dom=%d, id=%d] found\n",
+ import->dom_id, import->export_id);
+ init_fs_import(import);
+ }
+
+ fs_import = import;
+
+ if (!fs_import) {
+ printk("No FS import\n");
+ sleep(1000);
+ do_exit();
+ }
+}
diff --git a/extras/mini-os/include/fs.h b/extras/mini-os/include/fs.h
new file mode 100644
index 0000000000..1e144b4e6d
--- /dev/null
+++ b/extras/mini-os/include/fs.h
@@ -0,0 +1,51 @@
+#ifndef __FS_H__
+#define __FS_H__
+
+#include <xen/io/fsif.h>
+#include <semaphore.h>
+
+struct fs_import
+{
+ domid_t dom_id; /* dom id of the exporting domain */
+ u16 export_id; /* export id (exporting dom specific) */
+ u16 import_id; /* import id (specific to this domain) */
+ struct list_head list; /* list of all imports */
+ unsigned int nr_entries; /* Number of entries in rings & request
+ array */
+ struct fsif_front_ring ring; /* frontend ring (contains shared ring) */
+ int gnt_ref; /* grant reference to the shared ring */
+ evtchn_port_t local_port; /* local event channel port */
+ char *backend; /* XenBus location of the backend */
+ struct fs_request *requests; /* Table of requests */
+ unsigned short *freelist; /* List of free request ids */
+ struct semaphore reqs_sem; /* Accounts requests resource */
+};
+
+
+void init_fs_frontend(void);
+
+int fs_open(struct fs_import *import, char *file);
+int fs_close(struct fs_import *import, int fd);
+ssize_t fs_read(struct fs_import *import, int fd, void *buf,
+ ssize_t len, ssize_t offset);
+ssize_t fs_write(struct fs_import *import, int fd, void *buf,
+ ssize_t len, ssize_t offset);
+int fs_stat(struct fs_import *import,
+ int fd,
+ struct fsif_stat_response *stat);
+int fs_truncate(struct fs_import *import,
+ int fd,
+ int64_t length);
+int fs_remove(struct fs_import *import, char *file);
+int fs_rename(struct fs_import *import,
+ char *old_file_name,
+ char *new_file_name);
+int fs_create(struct fs_import *import, char *name,
+ int8_t directory, int32_t mode);
+char** fs_list(struct fs_import *import, char *name,
+ int32_t offset, int32_t *nr_files, int *has_more);
+int fs_chmod(struct fs_import *import, int fd, int32_t mode);
+int64_t fs_space(struct fs_import *import, char *location);
+int fs_sync(struct fs_import *import, int fd);
+
+#endif
diff --git a/extras/mini-os/include/types.h b/extras/mini-os/include/types.h
index f0b67607c3..d1b23c3a64 100644
--- a/extras/mini-os/include/types.h
+++ b/extras/mini-os/include/types.h
@@ -69,4 +69,7 @@ typedef s64 int64_t;
#define INT_MAX ((int)(~0U>>1))
#define UINT_MAX (~0U)
+
+typedef long ssize_t;
+typedef unsigned long size_t;
#endif /* _TYPES_H_ */
diff --git a/extras/mini-os/kernel.c b/extras/mini-os/kernel.c
index 095f38cd6a..9d18b22e1b 100644
--- a/extras/mini-os/kernel.c
+++ b/extras/mini-os/kernel.c
@@ -38,6 +38,7 @@
#include <xenbus.h>
#include <gnttab.h>
#include <netfront.h>
+#include <fs.h>
#include <xen/features.h>
#include <xen/version.h>
@@ -85,6 +86,11 @@ static void netfront_thread(void *p)
init_netfront(NULL, NULL, NULL);
}
+static void fs_thread(void *p)
+{
+ init_fs_frontend();
+}
+
/* This should be overridden by the application we are linked against. */
__attribute__((weak)) int app_main(start_info_t *si)
{
@@ -92,6 +98,7 @@ __attribute__((weak)) int app_main(start_info_t *si)
create_thread("xenbus_tester", xenbus_tester, si);
create_thread("periodic_thread", periodic_thread, si);
create_thread("netfront", netfront_thread, si);
+ create_thread("fs-frontend", fs_thread, si);
return 0;
}
diff --git a/tools/fs-back/Makefile b/tools/fs-back/Makefile
new file mode 100644
index 0000000000..4f75f277a9
--- /dev/null
+++ b/tools/fs-back/Makefile
@@ -0,0 +1,40 @@
+XEN_ROOT = ../..
+include $(XEN_ROOT)/tools/Rules.mk
+
+INCLUDES += -I.. -I../lib
+
+IBIN = fs-backend
+INST_DIR = /usr/sbin
+
+CFLAGS += -Werror
+CFLAGS += -Wno-unused
+CFLAGS += -fno-strict-aliasing
+CFLAGS += -I $(XEN_LIBXC)
+CFLAGS += $(INCLUDES) -I. -I../xenstore
+CFLAGS += -D_GNU_SOURCE
+
+# Get gcc to generate the dependencies for us.
+CFLAGS += -Wp,-MD,.$(@F).d
+DEPS = .*.d
+
+LIBS := -L. -L.. -L../lib
+LIBS += -L$(XEN_LIBXC)
+LIBS += -lxenctrl -lpthread -lrt
+LIBS += -L$(XEN_XENSTORE) -lxenstore
+
+OBJS := fs-xenbus.o fs-ops.o
+
+all: $(IBIN)
+
+fs-backend: $(OBJS) fs-backend.c
+ $(CC) $(CFLAGS) -o fs-backend $(OBJS) $(LIBS) fs-backend.c
+
+install: all
+ $(INSTALL_PROG) $(IBIN) $(DESTDIR)$(INST_DIR)
+
+clean:
+ rm -rf *.o *~ $(DEPS) xen $(IBIN) $(LIB)
+
+.PHONY: clean install
+
+-include $(DEPS)
diff --git a/tools/fs-back/fs-backend.c b/tools/fs-back/fs-backend.c
new file mode 100644
index 0000000000..634d5fa31e
--- /dev/null
+++ b/tools/fs-back/fs-backend.c
@@ -0,0 +1,346 @@
+#undef NDEBUG
+#include <stdio.h>
+#include <string.h>
+#include <assert.h>
+#include <malloc.h>
+#include <pthread.h>
+#include <xenctrl.h>
+#include <aio.h>
+#include <sys/mman.h>
+#include <sys/select.h>
+#include <xen/io/ring.h>
+#include "fs-backend.h"
+
+struct xs_handle *xsh = NULL;
+static struct fs_export *fs_exports = NULL;
+static int export_id = 0;
+static int mount_id = 0;
+
+void dispatch_response(struct mount *mount, int priv_req_id)
+{
+ int i;
+ struct fs_op *op;
+ struct fs_request *req = &mount->requests[priv_req_id];
+
+ for(i=0;;i++)
+ {
+ op = fsops[i];
+ /* We should dispatch a response before reaching the end of the array */
+ assert(op != NULL);
+ if(op->type == req->req_shadow.type)
+ {
+ printf("Found op for type=%d\n", op->type);
+ /* There needs to be a response handler */
+ assert(op->response_handler != NULL);
+ op->response_handler(mount, req);
+ break;
+ }
+ }
+
+ req->active = 0;
+ add_id_to_freelist(priv_req_id, mount->freelist);
+}
+
+static void handle_aio_events(struct mount *mount)
+{
+ int fd, ret, count, i, notify;
+ evtchn_port_t port;
+ /* AIO control block for the evtchn file destriptor */
+ struct aiocb evtchn_cb;
+ const struct aiocb * cb_list[mount->nr_entries];
+ int request_ids[mount->nr_entries];
+
+ /* Prepare the AIO control block for evtchn */
+ fd = xc_evtchn_fd(mount->evth);
+ bzero(&evtchn_cb, sizeof(struct aiocb));
+ evtchn_cb.aio_fildes = fd;
+ evtchn_cb.aio_nbytes = sizeof(port);
+ evtchn_cb.aio_buf = &port;
+ assert(aio_read(&evtchn_cb) == 0);
+
+wait_again:
+ /* Create list of active AIO requests */
+ count = 0;
+ for(i=0; i<mount->nr_entries; i++)
+ if(mount->requests[i].active)
+ {
+ cb_list[count] = &mount->requests[i].aiocb;
+ request_ids[count] = i;
+ count++;
+ }
+ /* Add the event channel at the end of the list. Event channel needs to be
+ * handled last as it exits this function. */
+ cb_list[count] = &evtchn_cb;
+ request_ids[count] = -1;
+ count++;
+
+ /* Block till an AIO requset finishes, or we get an event */
+ while(1) {
+ int ret = aio_suspend(cb_list, count, NULL);
+ if (!ret)
+ break;
+ assert(errno == EINTR);
+ }
+ for(i=0; i<count; i++)
+ if(aio_error(cb_list[i]) != EINPROGRESS)
+ {
+ if(request_ids[i] >= 0)
+ dispatch_response(mount, request_ids[i]);
+ else
+ goto read_event_channel;
+ }
+
+ RING_PUSH_RESPONSES_AND_CHECK_NOTIFY(&mount->ring, notify);
+ printf("Pushed responces and notify=%d\n", notify);
+ if(notify)
+ xc_evtchn_notify(mount->evth, mount->local_evtchn);
+
+ goto wait_again;
+
+read_event_channel:
+ assert(aio_return(&evtchn_cb) == sizeof(evtchn_port_t));
+ assert(xc_evtchn_unmask(mount->evth, mount->local_evtchn) >= 0);
+}
+
+
+void allocate_request_array(struct mount *mount)
+{
+ int i, nr_entries = mount->nr_entries;
+ struct fs_request *requests;
+ unsigned short *freelist;
+
+ requests = malloc(sizeof(struct fs_request) *nr_entries);
+ freelist = malloc(sizeof(unsigned short) * nr_entries);
+ memset(requests, 0, sizeof(struct fs_request) * nr_entries);
+ memset(freelist, 0, sizeof(unsigned short) * nr_entries);
+ for(i=0; i< nr_entries; i++)
+ {
+ requests[i].active = 0;
+ add_id_to_freelist(i, freelist);
+ }
+ mount->requests = requests;
+ mount->freelist = freelist;
+}
+
+
+void* handle_mount(void *data)
+{
+ int more, notify;
+ struct mount *mount = (struct mount *)data;
+
+ printf("Starting a thread for mount: %d\n", mount->mount_id);
+ allocate_request_array(mount);
+
+ for(;;)
+ {
+ int nr_consumed=0;
+ RING_IDX cons, rp;
+ struct fsif_request *req;
+
+ handle_aio_events(mount);
+moretodo:
+ rp = mount->ring.sring->req_prod;
+ rmb(); /* Ensure we see queued requests up to 'rp'. */
+
+ while ((cons = mount->ring.req_cons) != rp)
+ {
+ int i;
+ struct fs_op *op;
+
+ printf("Got a request at %d\n", cons);
+ req = RING_GET_REQUEST(&mount->ring, cons);
+ printf("Request type=%d\n", req->type);
+ for(i=0;;i++)
+ {
+ op = fsops[i];
+ if(op == NULL)
+ {
+ /* We've reached the end of the array, no appropirate
+ * handler found. Warn, ignore and continue. */
+ printf("WARN: Unknown request type: %d\n", req->type);
+ mount->ring.req_cons++;
+ break;
+ }
+ if(op->type == req->type)
+ {
+ /* There needs to be a dispatch handler */
+ assert(op->dispatch_handler != NULL);
+ op->dispatch_handler(mount, req);
+ break;
+ }
+ }
+
+ nr_consumed++;
+ }
+ printf("Backend consumed: %d requests\n", nr_consumed);
+ RING_FINAL_CHECK_FOR_REQUESTS(&mount->ring, more);
+ if(more) goto moretodo;
+
+ RING_PUSH_RESPONSES_AND_CHECK_NOTIFY(&mount->ring, notify);
+ printf("Pushed responces and notify=%d\n", notify);
+ if(notify)
+ xc_evtchn_notify(mount->evth, mount->local_evtchn);
+ }
+
+ printf("Destroying thread for mount: %d\n", mount->mount_id);
+ xc_gnttab_munmap(mount->gnth, mount->ring.sring, 1);
+ xc_gnttab_close(mount->gnth);
+ xc_evtchn_unbind(mount->evth, mount->local_evtchn);
+ xc_evtchn_close(mount->evth);
+ free(mount->frontend);
+ pthread_exit(NULL);
+}
+
+static void handle_connection(int frontend_dom_id, int export_id, char *frontend)
+{
+ struct mount *mount;
+ struct fs_export *export;
+ int evt_port;
+ pthread_t handling_thread;
+ struct fsif_sring *sring;
+
+ printf("Handling connection from dom=%d, for export=%d\n",
+ frontend_dom_id, export_id);
+ /* Try to find the export on the list */
+ export = fs_exports;
+ while(export)
+ {
+ if(export->export_id == export_id)
+ break;
+ export = export->next;
+ }
+ if(!export)
+ {
+ printf("Could not find the export (the id is unknown).\n");
+ return;
+ }
+
+ mount = (struct mount*)malloc(sizeof(struct mount));
+ mount->dom_id = frontend_dom_id;
+ mount->export = export;
+ mount->mount_id = mount_id++;
+ xenbus_read_mount_request(mount, frontend);
+ printf("Frontend found at: %s (gref=%d, evtchn=%d)\n",
+ mount->frontend, mount->gref, mount->remote_evtchn);
+ xenbus_write_backend_node(mount);
+ mount->evth = -1;
+ mount->evth = xc_evtchn_open();
+ assert(mount->evth != -1);
+ mount->local_evtchn = -1;
+ mount->local_evtchn = xc_evtchn_bind_interdomain(mount->evth,
+ mount->dom_id,
+ mount->remote_evtchn);
+ assert(mount->local_evtchn != -1);
+ mount->gnth = -1;
+ mount->gnth = xc_gnttab_open();
+ assert(mount->gnth != -1);
+ sring = xc_gnttab_map_grant_ref(mount->gnth,
+ mount->dom_id,
+ mount->gref,
+ PROT_READ | PROT_WRITE);
+ BACK_RING_INIT(&mount->ring, sring, PAGE_SIZE);
+ mount->nr_entries = mount->ring.nr_ents;
+ xenbus_write_backend_ready(mount);
+
+ pthread_create(&handling_thread, NULL, &handle_mount, mount);
+}
+
+static void await_connections(void)
+{
+ int fd, ret, dom_id, export_id;
+ fd_set fds;
+ char **watch_paths;
+ unsigned int len;
+ char d;
+
+ assert(xsh != NULL);
+ fd = xenbus_get_watch_fd();
+ /* Infinite watch loop */
+ do {
+ FD_ZERO(&fds);
+ FD_SET(fd, &fds);
+ ret = select(fd+1, &fds, NULL, NULL, NULL);
+ assert(ret == 1);
+ watch_paths = xs_read_watch(xsh, &len);
+ assert(len == 2);
+ assert(strcmp(watch_paths[1], "conn-watch") == 0);
+ dom_id = -1;
+ export_id = -1;
+ d = 0;
+ printf("Path changed %s\n", watch_paths[0]);
+ sscanf(watch_paths[0], WATCH_NODE"/%d/%d/fronten%c",
+ &dom_id, &export_id, &d);
+ if((dom_id >= 0) && (export_id >= 0) && d == 'd') {
+ char *frontend = xs_read(xsh, XBT_NULL, watch_paths[0], NULL);
+ if (frontend) {
+ handle_connection(dom_id, export_id, frontend);
+ xs_rm(xsh, XBT_NULL, watch_paths[0]);
+ }
+ }
+next_select:
+ printf("Awaiting next connection.\n");
+ /* TODO - we need to figure out what to free */
+ free(watch_paths);
+ } while (1);
+}
+
+struct fs_export* create_export(char *name, char *export_path)
+{
+ struct fs_export *curr_export, **last_export;
+
+ /* Create export structure */
+ curr_export = (struct fs_export *)malloc(sizeof(struct fs_export));
+ curr_export->name = name;
+ curr_export->export_path = export_path;
+ curr_export->export_id = export_id++;
+ /* Thread it onto the list */
+ curr_export->next = NULL;
+ last_export = &fs_exports;
+ while(*last_export)
+ last_export = &((*last_export)->next);
+ *last_export = curr_export;
+
+ return curr_export;
+}
+
+
+int main(void)
+{
+ struct fs_export *export;
+
+ /* Open the connection to XenStore first */
+ xsh = xs_domain_open();
+ assert(xsh != NULL);
+ xs_rm(xsh, XBT_NULL, ROOT_NODE);
+ /* Create watch node */
+ xenbus_create_request_node();
+
+ /* Create & register the default export */
+ export = create_export("default", "/exports");
+ xenbus_register_export(export);
+
+ await_connections();
+ /* Close the connection to XenStore when we are finished with everything */
+ xs_daemon_close(xsh);
+#if 0
+ int xc_handle;
+ char *shared_page;
+ int prot = PROT_READ | PROT_WRITE;
+
+ xc_handle = xc_gnttab_open();
+ printf("Main fn.\n");
+
+ shared_page = xc_gnttab_map_grant_ref(xc_handle,
+ 7,
+ 2047,
+ prot);
+
+ shared_page[20] = '\0';
+ printf("Current content of the page = %s\n", shared_page);
+ sprintf(shared_page, "%s", "Haha dirty page now! Very bad page.");
+ xc_gnttab_munmap(xc_handle, shared_page, 1);
+ xc_gnttab_close(xc_handle);
+ unrelated next line, saved for later convinience
+ xc_evtchn_notify(mount->evth, mount->local_evtchn);
+#endif
+}
diff --git a/tools/fs-back/fs-backend.h b/tools/fs-back/fs-backend.h
new file mode 100644
index 0000000000..9150d214a5
--- /dev/null
+++ b/tools/fs-back/fs-backend.h
@@ -0,0 +1,86 @@
+#ifndef __LIB_FS_BACKEND__
+#define __LIB_FS_BACKEND__
+
+#include <aio.h>
+#include <xs.h>
+#include <xen/grant_table.h>
+#include <xen/event_channel.h>
+#include <xen/io/ring.h>
+#include <xen/io/fsif.h>
+
+#define ROOT_NODE "backend/vfs"
+#define EXPORTS_SUBNODE "exports"
+#define EXPORTS_NODE ROOT_NODE"/"EXPORTS_SUBNODE
+#define WATCH_NODE EXPORTS_NODE"/requests"
+
+struct fs_export
+{
+ int export_id;
+ char *export_path;
+ char *name;
+ struct fs_export *next;
+};
+
+struct fs_request
+{
+ int active;
+ void *page; /* Pointer to mapped grant */
+ struct fsif_request req_shadow;
+ struct aiocb aiocb;
+};
+
+
+struct mount
+{
+ struct fs_export *export;
+ int dom_id;
+ char *frontend;
+ int mount_id; /* = backend id */
+ grant_ref_t gref;
+ evtchn_port_t remote_evtchn;
+ int evth; /* Handle to the event channel */
+ evtchn_port_t local_evtchn;
+ int gnth;
+ struct fsif_back_ring ring;
+ int nr_entries;
+ struct fs_request *requests;
+ unsigned short *freelist;
+};
+
+
+/* Handle to XenStore driver */
+extern struct xs_handle *xsh;
+
+bool xenbus_create_request_node(void);
+int xenbus_register_export(struct fs_export *export);
+int xenbus_get_watch_fd(void);
+void xenbus_read_mount_request(struct mount *mount, char *frontend);
+void xenbus_write_backend_node(struct mount *mount);
+void xenbus_write_backend_ready(struct mount *mount);
+
+/* File operations, implemented in fs-ops.c */
+struct fs_op
+{
+ int type; /* Type of request (from fsif.h) this handlers
+ are responsible for */
+ void (*dispatch_handler)(struct mount *mount, struct fsif_request *req);
+ void (*response_handler)(struct mount *mount, struct fs_request *req);
+};
+
+/* This NULL terminated array of all file requests handlers */
+extern struct fs_op *fsops[];
+
+static inline void add_id_to_freelist(unsigned int id,unsigned short* freelist)
+{
+ freelist[id] = freelist[0];
+ freelist[0] = id;
+}
+
+static inline unsigned short get_id_from_freelist(unsigned short* freelist)
+{
+ unsigned int id = freelist[0];
+ freelist[0] = freelist[id];
+ return id;
+}
+
+#endif /* __LIB_FS_BACKEND__ */
diff --git a/tools/fs-back/fs-ops.c b/tools/fs-back/fs-ops.c
new file mode 100644
index 0000000000..0be13234b0
--- /dev/null
+++ b/tools/fs-back/fs-ops.c
@@ -0,0 +1,658 @@
+#undef NDEBUG
+#include <stdio.h>
+#include <aio.h>
+#include <string.h>
+#include <assert.h>
+#include <fcntl.h>
+#include <dirent.h>
+#include <inttypes.h>
+#include <xenctrl.h>
+#include <sys/mman.h>
+#include <sys/types.h>
+#include <sys/stat.h>
+#include <sys/vfs.h>
+#include <sys/mount.h>
+#include <unistd.h>
+#include "fs-backend.h"
+
+/* For debugging only */
+#include <sys/time.h>
+#include <time.h>
+
+
+#define BUFFER_SIZE 1024
+
+
+unsigned short get_request(struct mount *mount, struct fsif_request *req)
+{
+ unsigned short id = get_id_from_freelist(mount->freelist);
+
+ printf("Private Request id: %d\n", id);
+ memcpy(&mount->requests[id].req_shadow, req, sizeof(struct fsif_request));
+ mount->requests[id].active = 1;
+
+ return id;
+}
+
+
+void dispatch_file_open(struct mount *mount, struct fsif_request *req)
+{
+ char *file_name, full_path[BUFFER_SIZE];
+ int fd;
+ struct timeval tv1, tv2;
+ RING_IDX rsp_idx;
+ fsif_response_t *rsp;
+ uint16_t req_id;
+
+ printf("Dispatching file open operation (gref=%d).\n", req->u.fopen.gref);
+ /* Read the request, and open file */
+ file_name = xc_gnttab_map_grant_ref(mount->gnth,
+ mount->dom_id,
+ req->u.fopen.gref,
+ PROT_READ);
+
+ req_id = req->id;
+ printf("File open issued for %s\n", file_name);
+ assert(BUFFER_SIZE >
+ strlen(file_name) + strlen(mount->export->export_path) + 1);
+ sprintf(full_path, "%s/%s", mount->export->export_path, file_name);
+ assert(xc_gnttab_munmap(mount->gnth, file_name, 1) == 0);
+ printf("Issuing open for %s\n", full_path);
+ fd = open(full_path, O_RDWR);
+ printf("Got FD: %d\n", fd);
+ /* We can advance the request consumer index, from here on, the request
+ * should not be used (it may be overrinden by a response) */
+ mount->ring.req_cons++;
+
+
+ /* Get a response from the ring */
+ rsp_idx = mount->ring.rsp_prod_pvt++;
+ printf("Writing response at: idx=%d, id=%d\n", rsp_idx, req_id);
+ rsp = RING_GET_RESPONSE(&mount->ring, rsp_idx);
+ rsp->id = req_id;
+ rsp->ret_val = (uint64_t)fd;
+}
+
+void dispatch_file_close(struct mount *mount, struct fsif_request *req)
+{
+ int ret;
+ RING_IDX rsp_idx;
+ fsif_response_t *rsp;
+ uint16_t req_id;
+
+ printf("Dispatching file close operation (fd=%d).\n", req->u.fclose.fd);
+
+ req_id = req->id;
+ ret = close(req->u.fclose.fd);
+ printf("Got ret: %d\n", ret);
+ /* We can advance the request consumer index, from here on, the request
+ * should not be used (it may be overrinden by a response) */
+ mount->ring.req_cons++;
+
+
+ /* Get a response from the ring */
+ rsp_idx = mount->ring.rsp_prod_pvt++;
+ printf("Writing response at: idx=%d, id=%d\n", rsp_idx, req_id);
+ rsp = RING_GET_RESPONSE(&mount->ring, rsp_idx);
+ rsp->id = req_id;
+ rsp->ret_val = (uint64_t)ret;
+}
+void dispatch_file_read(struct mount *mount, struct fsif_request *req)
+{
+ void *buf;
+ int fd;
+ uint16_t req_id;
+ unsigned short priv_id;
+ struct fs_request *priv_req;
+
+ /* Read the request */
+ buf = xc_gnttab_map_grant_ref(mount->gnth,
+ mount->dom_id,
+ req->u.fread.gref,
+ PROT_WRITE);
+
+ req_id = req->id;
+ printf("File read issued for FD=%d (len=%"PRIu64", offest=%"PRIu64")\n",
+ req->u.fread.fd, req->u.fread.len, req->u.fread.offset);
+
+ priv_id = get_request(mount, req);
+ printf("Private id is: %d\n", priv_id);
+ priv_req = &mount->requests[priv_id];
+ priv_req->page = buf;
+
+ /* Dispatch AIO read request */
+ bzero(&priv_req->aiocb, sizeof(struct aiocb));
+ priv_req->aiocb.aio_fildes = req->u.fread.fd;
+ priv_req->aiocb.aio_nbytes = req->u.fread.len;
+ priv_req->aiocb.aio_offset = req->u.fread.offset;
+ priv_req->aiocb.aio_buf = buf;
+ assert(aio_read(&priv_req->aiocb) >= 0);
+
+
+ /* We can advance the request consumer index, from here on, the request
+ * should not be used (it may be overrinden by a response) */
+ mount->ring.req_cons++;
+}
+
+void end_file_read(struct mount *mount, struct fs_request *priv_req)
+{
+ RING_IDX rsp_idx;
+ fsif_response_t *rsp;
+ uint16_t req_id;
+
+ /* Release the grant */
+ assert(xc_gnttab_munmap(mount->gnth, priv_req->page, 1) == 0);
+
+ /* Get a response from the ring */
+ rsp_idx = mount->ring.rsp_prod_pvt++;
+ req_id = priv_req->req_shadow.id;
+ printf("Writing response at: idx=%d, id=%d\n", rsp_idx, req_id);
+ rsp = RING_GET_RESPONSE(&mount->ring, rsp_idx);
+ rsp->id = req_id;
+ rsp->ret_val = (uint64_t)aio_return(&priv_req->aiocb);
+}
+
+void dispatch_file_write(struct mount *mount, struct fsif_request *req)
+{
+ void *buf;
+ int fd;
+ uint16_t req_id;
+ unsigned short priv_id;
+ struct fs_request *priv_req;
+
+ /* Read the request */
+ buf = xc_gnttab_map_grant_ref(mount->gnth,
+ mount->dom_id,
+ req->u.fwrite.gref,
+ PROT_READ);
+
+ req_id = req->id;
+ printf("File write issued for FD=%d (len=%"PRIu64", offest=%"PRIu64")\n",
+ req->u.fwrite.fd, req->u.fwrite.len, req->u.fwrite.offset);
+
+ priv_id = get_request(mount, req);
+ printf("Private id is: %d\n", priv_id);
+ priv_req = &mount->requests[priv_id];
+ priv_req->page = buf;
+
+ /* Dispatch AIO write request */
+ bzero(&priv_req->aiocb, sizeof(struct aiocb));
+ priv_req->aiocb.aio_fildes = req->u.fwrite.fd;
+ priv_req->aiocb.aio_nbytes = req->u.fwrite.len;
+ priv_req->aiocb.aio_offset = req->u.fwrite.offset;
+ priv_req->aiocb.aio_buf = buf;
+ assert(aio_write(&priv_req->aiocb) >= 0);
+
+
+ /* We can advance the request consumer index, from here on, the request
+ * should not be used (it may be overrinden by a response) */
+ mount->ring.req_cons++;
+}
+
+void end_file_write(struct mount *mount, struct fs_request *priv_req)
+{
+ RING_IDX rsp_idx;
+ fsif_response_t *rsp;
+ uint16_t req_id;
+
+ /* Release the grant */
+ assert(xc_gnttab_munmap(mount->gnth, priv_req->page, 1) == 0);
+
+ /* Get a response from the ring */
+ rsp_idx = mount->ring.rsp_prod_pvt++;
+ req_id = priv_req->req_shadow.id;
+ printf("Writing response at: idx=%d, id=%d\n", rsp_idx, req_id);
+ rsp = RING_GET_RESPONSE(&mount->ring, rsp_idx);
+ rsp->id = req_id;
+ rsp->ret_val = (uint64_t)aio_return(&priv_req->aiocb);
+}
+
+void dispatch_stat(struct mount *mount, struct fsif_request *req)
+{
+ struct fsif_stat_response *buf;
+ struct stat stat;
+ int fd, ret;
+ uint16_t req_id;
+ RING_IDX rsp_idx;
+ fsif_response_t *rsp;
+
+ /* Read the request */
+ buf = xc_gnttab_map_grant_ref(mount->gnth,
+ mount->dom_id,
+ req->u.fstat.gref,
+ PROT_WRITE);
+
+ req_id = req->id;
+ fd = req->u.fstat.fd;
+ printf("File stat issued for FD=%d\n", fd);
+
+ /* We can advance the request consumer index, from here on, the request
+ * should not be used (it may be overrinden by a response) */
+ mount->ring.req_cons++;
+
+ /* Stat, and create the response */
+ ret = fstat(fd, &stat);
+ printf("Mode=%o, uid=%d, a_time=%ld\n",
+ stat.st_mode, stat.st_uid, stat.st_atime);
+ buf->stat_mode = stat.st_mode;
+ buf->stat_uid = stat.st_uid;
+ buf->stat_gid = stat.st_gid;
+#ifdef BLKGETSIZE
+ if (S_ISBLK(stat.st_mode)) {
+ int sectors;
+ if (ioctl(fd, BLKGETSIZE, &sectors)) {
+ perror("getting device size\n");
+ buf->stat_size = 0;
+ } else
+ buf->stat_size = sectors << 9;
+ } else
+#endif
+ buf->stat_size = stat.st_size;
+ buf->stat_atime = stat.st_atime;
+ buf->stat_mtime = stat.st_mtime;
+ buf->stat_ctime = stat.st_ctime;
+
+ /* Release the grant */
+ assert(xc_gnttab_munmap(mount->gnth, buf, 1) == 0);
+
+ /* Get a response from the ring */
+ rsp_idx = mount->ring.rsp_prod_pvt++;
+ printf("Writing response at: idx=%d, id=%d\n", rsp_idx, req_id);
+ rsp = RING_GET_RESPONSE(&mount->ring, rsp_idx);
+ rsp->id = req_id;
+ rsp->ret_val = (uint64_t)ret;
+}
+
+
+void dispatch_truncate(struct mount *mount, struct fsif_request *req)
+{
+ int fd, ret;
+ uint16_t req_id;
+ RING_IDX rsp_idx;
+ fsif_response_t *rsp;
+ int64_t length;
+
+ req_id = req->id;
+ fd = req->u.ftruncate.fd;
+ length = req->u.ftruncate.length;
+ printf("File truncate issued for FD=%d, length=%"PRId64"\n", fd, length);
+
+ /* We can advance the request consumer index, from here on, the request
+ * should not be used (it may be overrinden by a response) */
+ mount->ring.req_cons++;
+
+ /* Stat, and create the response */
+ ret = ftruncate(fd, length);
+
+ /* Get a response from the ring */
+ rsp_idx = mount->ring.rsp_prod_pvt++;
+ printf("Writing response at: idx=%d, id=%d\n", rsp_idx, req_id);
+ rsp = RING_GET_RESPONSE(&mount->ring, rsp_idx);
+ rsp->id = req_id;
+ rsp->ret_val = (uint64_t)ret;
+}
+
+void dispatch_remove(struct mount *mount, struct fsif_request *req)
+{
+ char *file_name, full_path[BUFFER_SIZE];
+ int ret;
+ RING_IDX rsp_idx;
+ fsif_response_t *rsp;
+ uint16_t req_id;
+
+ printf("Dispatching remove operation (gref=%d).\n", req->u.fremove.gref);
+ /* Read the request, and open file */
+ file_name = xc_gnttab_map_grant_ref(mount->gnth,
+ mount->dom_id,
+ req->u.fremove.gref,
+ PROT_READ);
+
+ req_id = req->id;
+ printf("File remove issued for %s\n", file_name);
+ assert(BUFFER_SIZE >
+ strlen(file_name) + strlen(mount->export->export_path) + 1);
+ sprintf(full_path, "%s/%s", mount->export->export_path, file_name);
+ assert(xc_gnttab_munmap(mount->gnth, file_name, 1) == 0);
+ printf("Issuing remove for %s\n", full_path);
+ ret = remove(full_path);
+ printf("Got ret: %d\n", ret);
+ /* We can advance the request consumer index, from here on, the request
+ * should not be used (it may be overrinden by a response) */
+ mount->ring.req_cons++;
+
+
+ /* Get a response from the ring */
+ rsp_idx = mount->ring.rsp_prod_pvt++;
+ printf("Writing response at: idx=%d, id=%d\n", rsp_idx, req_id);
+ rsp = RING_GET_RESPONSE(&mount->ring, rsp_idx);
+ rsp->id = req_id;
+ rsp->ret_val = (uint64_t)ret;
+}
+
+
+void dispatch_rename(struct mount *mount, struct fsif_request *req)
+{
+ char *buf, *old_file_name, *new_file_name;
+ char old_full_path[BUFFER_SIZE], new_full_path[BUFFER_SIZE];
+ int ret;
+ RING_IDX rsp_idx;
+ fsif_response_t *rsp;
+ uint16_t req_id;
+
+ printf("Dispatching rename operation (gref=%d).\n", req->u.fremove.gref);
+ /* Read the request, and open file */
+ buf = xc_gnttab_map_grant_ref(mount->gnth,
+ mount->dom_id,
+ req->u.frename.gref,
+ PROT_READ);
+
+ req_id = req->id;
+ old_file_name = buf + req->u.frename.old_name_offset;
+ new_file_name = buf + req->u.frename.new_name_offset;
+ printf("File rename issued for %s -> %s (buf=%s)\n",
+ old_file_name, new_file_name, buf);
+ assert(BUFFER_SIZE >
+ strlen(old_file_name) + strlen(mount->export->export_path) + 1);
+ assert(BUFFER_SIZE >
+ strlen(new_file_name) + strlen(mount->export->export_path) + 1);
+ sprintf(old_full_path, "%s/%s", mount->export->export_path, old_file_name);
+ sprintf(new_full_path, "%s/%s", mount->export->export_path, new_file_name);
+ assert(xc_gnttab_munmap(mount->gnth, buf, 1) == 0);
+ printf("Issuing rename for %s -> %s\n", old_full_path, new_full_path);
+ ret = rename(old_full_path, new_full_path);
+ printf("Got ret: %d\n", ret);
+ /* We can advance the request consumer index, from here on, the request
+ * should not be used (it may be overrinden by a response) */
+ mount->ring.req_cons++;
+
+
+ /* Get a response from the ring */
+ rsp_idx = mount->ring.rsp_prod_pvt++;
+ printf("Writing response at: idx=%d, id=%d\n", rsp_idx, req_id);
+ rsp = RING_GET_RESPONSE(&mount->ring, rsp_idx);
+ rsp->id = req_id;
+ rsp->ret_val = (uint64_t)ret;
+}
+
+
+void dispatch_create(struct mount *mount, struct fsif_request *req)
+{
+ char *file_name, full_path[BUFFER_SIZE];
+ int ret;
+ int8_t directory;
+ int32_t mode;
+ RING_IDX rsp_idx;
+ fsif_response_t *rsp;
+ uint16_t req_id;
+
+ printf("Dispatching file create operation (gref=%d).\n", req->u.fcreate.gref);
+ /* Read the request, and create file/directory */
+ mode = req->u.fcreate.mode;
+ directory = req->u.fcreate.directory;
+ file_name = xc_gnttab_map_grant_ref(mount->gnth,
+ mount->dom_id,
+ req->u.fcreate.gref,
+ PROT_READ);
+
+ req_id = req->id;
+ printf("File create issued for %s\n", file_name);
+ assert(BUFFER_SIZE >
+ strlen(file_name) + strlen(mount->export->export_path) + 1);
+ sprintf(full_path, "%s/%s", mount->export->export_path, file_name);
+ assert(xc_gnttab_munmap(mount->gnth, file_name, 1) == 0);
+ /* We can advance the request consumer index, from here on, the request
+ * should not be used (it may be overrinden by a response) */
+ mount->ring.req_cons++;
+
+ if(directory)
+ {
+ printf("Issuing create for directory: %s\n", full_path);
+ ret = mkdir(full_path, mode);
+ }
+ else
+ {
+ printf("Issuing create for file: %s\n", full_path);
+ ret = creat(full_path, mode);
+ }
+ printf("Got ret %d (errno=%d)\n", ret, errno);
+
+ /* Get a response from the ring */
+ rsp_idx = mount->ring.rsp_prod_pvt++;
+ printf("Writing response at: idx=%d, id=%d\n", rsp_idx, req_id);
+ rsp = RING_GET_RESPONSE(&mount->ring, rsp_idx);
+ rsp->id = req_id;
+ rsp->ret_val = (uint64_t)ret;
+}
+
+void dispatch_list(struct mount *mount, struct fsif_request *req)
+{
+ char *file_name, *buf, full_path[BUFFER_SIZE];
+ uint32_t offset, nr_files, error_code;
+ uint64_t ret_val;
+ RING_IDX rsp_idx;
+ fsif_response_t *rsp;
+ uint16_t req_id;
+ DIR *dir;
+ struct dirent *dirent = NULL;
+
+ printf("Dispatching list operation (gref=%d).\n", req->u.flist.gref);
+ /* Read the request, and list directory */
+ offset = req->u.flist.offset;
+ buf = file_name = xc_gnttab_map_grant_ref(mount->gnth,
+ mount->dom_id,
+ req->u.flist.gref,
+ PROT_READ | PROT_WRITE);
+
+ req_id = req->id;
+ printf("Dir list issued for %s\n", file_name);
+ assert(BUFFER_SIZE >
+ strlen(file_name) + strlen(mount->export->export_path) + 1);
+ sprintf(full_path, "%s/%s", mount->export->export_path, file_name);
+ /* We can advance the request consumer index, from here on, the request
+ * should not be used (it may be overrinden by a response) */
+ mount->ring.req_cons++;
+
+ ret_val = 0;
+ nr_files = 0;
+ dir = opendir(full_path);
+ if(dir == NULL)
+ {
+ error_code = errno;
+ goto error_out;
+ }
+ /* Skip offset dirs */
+ dirent = readdir(dir);
+ while(offset-- > 0 && dirent != NULL)
+ dirent = readdir(dir);
+ /* If there was any error with reading the directory, errno will be set */
+ error_code = errno;
+ /* Copy file names of the remaining non-NULL dirents into buf */
+ assert(NAME_MAX < PAGE_SIZE >> 1);
+ while(dirent != NULL &&
+ (PAGE_SIZE - ((unsigned long)buf & PAGE_MASK) > NAME_MAX))
+ {
+ int curr_length = strlen(dirent->d_name) + 1;
+
+ memcpy(buf, dirent->d_name, curr_length);
+ buf += curr_length;
+ dirent = readdir(dir);
+ error_code = errno;
+ nr_files++;
+ }
+error_out:
+ ret_val = ((nr_files << NR_FILES_SHIFT) & NR_FILES_MASK) |
+ ((error_code << ERROR_SHIFT) & ERROR_MASK) |
+ (dirent != NULL ? HAS_MORE_FLAG : 0);
+ assert(xc_gnttab_munmap(mount->gnth, file_name, 1) == 0);
+
+ /* Get a response from the ring */
+ rsp_idx = mount->ring.rsp_prod_pvt++;
+ printf("Writing response at: idx=%d, id=%d\n", rsp_idx, req_id);
+ rsp = RING_GET_RESPONSE(&mount->ring, rsp_idx);
+ rsp->id = req_id;
+ rsp->ret_val = ret_val;
+}
+
+void dispatch_chmod(struct mount *mount, struct fsif_request *req)
+{
+ int fd, ret;
+ RING_IDX rsp_idx;
+ fsif_response_t *rsp;
+ uint16_t req_id;
+ int32_t mode;
+
+ printf("Dispatching file chmod operation (fd=%d, mode=%o).\n",
+ req->u.fchmod.fd, req->u.fchmod.mode);
+ req_id = req->id;
+ fd = req->u.fchmod.fd;
+ mode = req->u.fchmod.mode;
+ /* We can advance the request consumer index, from here on, the request
+ * should not be used (it may be overrinden by a response) */
+ mount->ring.req_cons++;
+
+ ret = fchmod(fd, mode);
+
+ /* Get a response from the ring */
+ rsp_idx = mount->ring.rsp_prod_pvt++;
+ printf("Writing response at: idx=%d, id=%d\n", rsp_idx, req_id);
+ rsp = RING_GET_RESPONSE(&mount->ring, rsp_idx);
+ rsp->id = req_id;
+ rsp->ret_val = (uint64_t)ret;
+}
+
+void dispatch_fs_space(struct mount *mount, struct fsif_request *req)
+{
+ char *file_name, full_path[BUFFER_SIZE];
+ RING_IDX rsp_idx;
+ fsif_response_t *rsp;
+ uint16_t req_id;
+ struct statfs stat;
+ int64_t ret;
+
+ printf("Dispatching fs space operation (gref=%d).\n", req->u.fspace.gref);
+ /* Read the request, and open file */
+ file_name = xc_gnttab_map_grant_ref(mount->gnth,
+ mount->dom_id,
+ req->u.fspace.gref,
+ PROT_READ);
+
+ req_id = req->id;
+ printf("Fs space issued for %s\n", file_name);
+ assert(BUFFER_SIZE >
+ strlen(file_name) + strlen(mount->export->export_path) + 1);
+ sprintf(full_path, "%s/%s", mount->export->export_path, file_name);
+ assert(xc_gnttab_munmap(mount->gnth, file_name, 1) == 0);
+ printf("Issuing fs space for %s\n", full_path);
+ ret = statfs(full_path, &stat);
+ if(ret >= 0)
+ ret = stat.f_bsize * stat.f_bfree;
+
+ /* We can advance the request consumer index, from here on, the request
+ * should not be used (it may be overrinden by a response) */
+ mount->ring.req_cons++;
+
+
+ /* Get a response from the ring */
+ rsp_idx = mount->ring.rsp_prod_pvt++;
+ printf("Writing response at: idx=%d, id=%d\n", rsp_idx, req_id);
+ rsp = RING_GET_RESPONSE(&mount->ring, rsp_idx);
+ rsp->id = req_id;
+ rsp->ret_val = (uint64_t)ret;
+}
+
+void dispatch_file_sync(struct mount *mount, struct fsif_request *req)
+{
+ int fd;
+ uint16_t req_id;
+ unsigned short priv_id;
+ struct fs_request *priv_req;
+
+ req_id = req->id;
+ fd = req->u.fsync.fd;
+ printf("File sync issued for FD=%d\n", fd);
+
+ priv_id = get_request(mount, req);
+ printf("Private id is: %d\n", priv_id);
+ priv_req = &mount->requests[priv_id];
+
+ /* Dispatch AIO read request */
+ bzero(&priv_req->aiocb, sizeof(struct aiocb));
+ priv_req->aiocb.aio_fildes = fd;
+ assert(aio_fsync(O_SYNC, &priv_req->aiocb) >= 0);
+
+
+ /* We can advance the request consumer index, from here on, the request
+ * should not be used (it may be overrinden by a response) */
+ mount->ring.req_cons++;
+}
+
+void end_file_sync(struct mount *mount, struct fs_request *priv_req)
+{
+ RING_IDX rsp_idx;
+ fsif_response_t *rsp;
+ uint16_t req_id;
+
+ /* Get a response from the ring */
+ rsp_idx = mount->ring.rsp_prod_pvt++;
+ req_id = priv_req->req_shadow.id;
+ printf("Writing response at: idx=%d, id=%d\n", rsp_idx, req_id);
+ rsp = RING_GET_RESPONSE(&mount->ring, rsp_idx);
+ rsp->id = req_id;
+ rsp->ret_val = (uint64_t)aio_return(&priv_req->aiocb);
+}
+
+struct fs_op fopen_op = {.type = REQ_FILE_OPEN,
+ .dispatch_handler = dispatch_file_open,
+ .response_handler = NULL};
+struct fs_op fclose_op = {.type = REQ_FILE_CLOSE,
+ .dispatch_handler = dispatch_file_close,
+ .response_handler = NULL};
+struct fs_op fread_op = {.type = REQ_FILE_READ,
+ .dispatch_handler = dispatch_file_read,
+ .response_handler = end_file_read};
+struct fs_op fwrite_op = {.type = REQ_FILE_WRITE,
+ .dispatch_handler = dispatch_file_write,
+ .response_handler = end_file_write};
+struct fs_op fstat_op = {.type = REQ_STAT,
+ .dispatch_handler = dispatch_stat,
+ .response_handler = NULL};
+struct fs_op ftruncate_op = {.type = REQ_FILE_TRUNCATE,
+ .dispatch_handler = dispatch_truncate,
+ .response_handler = NULL};
+struct fs_op fremove_op = {.type = REQ_REMOVE,
+ .dispatch_handler = dispatch_remove,
+ .response_handler = NULL};
+struct fs_op frename_op = {.type = REQ_RENAME,
+ .dispatch_handler = dispatch_rename,
+ .response_handler = NULL};
+struct fs_op fcreate_op = {.type = REQ_CREATE,
+ .dispatch_handler = dispatch_create,
+ .response_handler = NULL};
+struct fs_op flist_op = {.type = REQ_DIR_LIST,
+ .dispatch_handler = dispatch_list,
+ .response_handler = NULL};
+struct fs_op fchmod_op = {.type = REQ_CHMOD,
+ .dispatch_handler = dispatch_chmod,
+ .response_handler = NULL};
+struct fs_op fspace_op = {.type = REQ_FS_SPACE,
+ .dispatch_handler = dispatch_fs_space,
+ .response_handler = NULL};
+struct fs_op fsync_op = {.type = REQ_FILE_SYNC,
+ .dispatch_handler = dispatch_file_sync,
+ .response_handler = end_file_sync};
+
+
+struct fs_op *fsops[] = {&fopen_op,
+ &fclose_op,
+ &fread_op,
+ &fwrite_op,
+ &fstat_op,
+ &ftruncate_op,
+ &fremove_op,
+ &frename_op,
+ &fcreate_op,
+ &flist_op,
+ &fchmod_op,
+ &fspace_op,
+ &fsync_op,
+ NULL};
diff --git a/tools/fs-back/fs-xenbus.c b/tools/fs-back/fs-xenbus.c
new file mode 100644
index 0000000000..c0c7621fba
--- /dev/null
+++ b/tools/fs-back/fs-xenbus.c
@@ -0,0 +1,180 @@
+#undef NDEBUG
+#include <stdio.h>
+#include <stdlib.h>
+#include <stdarg.h>
+#include <string.h>
+#include <assert.h>
+#include <xenctrl.h>
+#include <xs.h>
+#include <xen/io/fsif.h>
+#include "fs-backend.h"
+
+
+static bool xenbus_printf(struct xs_handle *xsh,
+ xs_transaction_t xbt,
+ char* node,
+ char* path,
+ char* fmt,
+ ...)
+{
+ char fullpath[1024];
+ char val[1024];
+ va_list args;
+
+ va_start(args, fmt);
+ sprintf(fullpath,"%s/%s", node, path);
+ vsprintf(val, fmt, args);
+ va_end(args);
+ printf("xenbus_printf (%s) <= %s.\n", fullpath, val);
+
+ return xs_write(xsh, xbt, fullpath, val, strlen(val));
+}
+
+bool xenbus_create_request_node(void)
+{
+ bool ret;
+ struct xs_permissions perms;
+
+ assert(xsh != NULL);
+ xs_rm(xsh, XBT_NULL, WATCH_NODE);
+ ret = xs_mkdir(xsh, XBT_NULL, WATCH_NODE);
+ if (!ret)
+ return false;
+
+ perms.id = 0;
+ perms.perms = XS_PERM_WRITE;
+ ret = xs_set_permissions(xsh, XBT_NULL, WATCH_NODE, &perms, 1);
+
+ return ret;
+}
+
+int xenbus_register_export(struct fs_export *export)
+{
+ xs_transaction_t xst = 0;
+ char node[1024];
+ struct xs_permissions perms;
+
+ assert(xsh != NULL);
+ if(xsh == NULL)
+ {
+ printf("Could not open connection to xenbus deamon.\n");
+ goto error_exit;
+ }
+ printf("Connection to the xenbus deamon opened successfully.\n");
+
+ /* Start transaction */
+ xst = xs_transaction_start(xsh);
+ if(xst == 0)
+ {
+ printf("Could not start a transaction.\n");
+ goto error_exit;
+ }
+ printf("XS transaction is %d\n", xst);
+
+ /* Create node string */
+ sprintf(node, "%s/%d", EXPORTS_NODE, export->export_id);
+ /* Remove old export (if exists) */
+ xs_rm(xsh, xst, node);
+
+ if(!xenbus_printf(xsh, xst, node, "name", "%s", export->name))
+ {
+ printf("Could not write the export node.\n");
+ goto error_exit;
+ }
+
+ /* People need to be able to read our export */
+ perms.id = 0;
+ perms.perms = XS_PERM_READ;
+ if(!xs_set_permissions(xsh, xst, EXPORTS_NODE, &perms, 1))
+ {
+ printf("Could not set permissions on the export node.\n");
+ goto error_exit;
+ }
+
+ xs_transaction_end(xsh, xst, 0);
+ return 0;
+
+error_exit:
+ if(xst != 0)
+ xs_transaction_end(xsh, xst, 1);
+ return -1;
+}
+
+int xenbus_get_watch_fd(void)
+{
+ int res;
+ assert(xsh != NULL);
+ res = xs_watch(xsh, WATCH_NODE, "conn-watch");
+ assert(res);
+ return xs_fileno(xsh);
+}
+
+void xenbus_read_mount_request(struct mount *mount, char *frontend)
+{
+ char node[1024];
+ char *s;
+
+ assert(xsh != NULL);
+#if 0
+ sprintf(node, WATCH_NODE"/%d/%d/frontend",
+ mount->dom_id, mount->export->export_id);
+ frontend = xs_read(xsh, XBT_NULL, node, NULL);
+#endif
+ mount->frontend = frontend;
+ sprintf(node, "%s/state", frontend);
+ s = xs_read(xsh, XBT_NULL, node, NULL);
+ assert(strcmp(s, STATE_READY) == 0);
+ free(s);
+ sprintf(node, "%s/ring-ref", frontend);
+ s = xs_read(xsh, XBT_NULL, node, NULL);
+ mount->gref = atoi(s);
+ free(s);
+ sprintf(node, "%s/event-channel", frontend);
+ s = xs_read(xsh, XBT_NULL, node, NULL);
+ mount->remote_evtchn = atoi(s);
+ free(s);
+}
+
+/* Small utility function to figure out our domain id */
+static int get_self_id(void)
+{
+ char *dom_id;
+ int ret;
+
+ assert(xsh != NULL);
+ dom_id = xs_read(xsh, XBT_NULL, "domid", NULL);
+ sscanf(dom_id, "%d", &ret);
+ free(dom_id);
+
+ return ret;
+}
+
+
+void xenbus_write_backend_node(struct mount *mount)
+{
+ char node[1024], backend_node[1024];
+ int self_id;
+
+ assert(xsh != NULL);
+ self_id = get_self_id();
+ printf("Our own dom_id=%d\n", self_id);
+ sprintf(node, "%s/backend", mount->frontend);
+ sprintf(backend_node, "/local/domain/%d/"ROOT_NODE"/%d",
+ self_id, mount->mount_id);
+ xs_write(xsh, XBT_NULL, node, backend_node, strlen(backend_node));
+
+ sprintf(node, ROOT_NODE"/%d/state", mount->mount_id);
+ xs_write(xsh, XBT_NULL, node, STATE_INITIALISED, strlen(STATE_INITIALISED));
+}
+
+void xenbus_write_backend_ready(struct mount *mount)
+{
+ char node[1024];
+ int self_id;
+
+ assert(xsh != NULL);
+ self_id = get_self_id();
+ sprintf(node, ROOT_NODE"/%d/state", mount->mount_id);
+ xs_write(xsh, XBT_NULL, node, STATE_READY, strlen(STATE_READY));
+}
+
diff --git a/xen/include/public/io/fsif.h b/xen/include/public/io/fsif.h
new file mode 100644
index 0000000000..8abc075f6e
--- /dev/null
+++ b/xen/include/public/io/fsif.h
@@ -0,0 +1,181 @@
+/******************************************************************************
+ * fsif.h
+ *
+ * Interface to FS level split device drivers.
+ *
+ * Permission is hereby granted, free of charge, to any person obtaining a copy
+ * of this software and associated documentation files (the "Software"), to
+ * deal in the Software without restriction, including without limitation the
+ * rights to use, copy, modify, merge, publish, distribute, sublicense, and/or
+ * sell copies of the Software, and to permit persons to whom the Software is
+ * furnished to do so, subject to the following conditions:
+ *
+ * The above copyright notice and this permission notice shall be included in
+ * all copies or substantial portions of the Software.
+ *
+ * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
+ * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
+ * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
+ * AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
+ * LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING
+ * FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER
+ * DEALINGS IN THE SOFTWARE.
+ *
+ * Copyright (c) 2007, Grzegorz Milos, Sun Microsystems, Inc.
+ */
+
+#ifndef __XEN_PUBLIC_IO_FSIF_H__
+#define __XEN_PUBLIC_IO_FSIF_H__
+
+#include "ring.h"
+#include "../grant_table.h"
+
+#define REQ_FILE_OPEN 1
+#define REQ_FILE_CLOSE 2
+#define REQ_FILE_READ 3
+#define REQ_FILE_WRITE 4
+#define REQ_STAT 5
+#define REQ_FILE_TRUNCATE 6
+#define REQ_REMOVE 7
+#define REQ_RENAME 8
+#define REQ_CREATE 9
+#define REQ_DIR_LIST 10
+#define REQ_CHMOD 11
+#define REQ_FS_SPACE 12
+#define REQ_FILE_SYNC 13
+
+struct fsif_open_request {
+ grant_ref_t gref;
+};
+
+struct fsif_close_request {
+ uint32_t fd;
+};
+
+struct fsif_read_request {
+ uint32_t fd;
+ grant_ref_t gref;
+ uint64_t len;
+ uint64_t offset;
+};
+
+struct fsif_write_request {
+ uint32_t fd;
+ grant_ref_t gref;
+ uint64_t len;
+ uint64_t offset;
+};
+
+struct fsif_stat_request {
+ uint32_t fd;
+ grant_ref_t gref;
+};
+
+/* This structure is a copy of some fields from stat structure, writen to the
+ * granted page. */
+struct fsif_stat_response {
+ int32_t stat_mode;
+ uint32_t stat_uid;
+ uint32_t stat_gid;
+ int32_t pad;
+ int64_t stat_size;
+ int64_t stat_atime;
+ int64_t stat_mtime;
+ int64_t stat_ctime;
+};
+
+struct fsif_truncate_request {
+ uint32_t fd;
+ int32_t pad;
+ int64_t length;
+};
+
+struct fsif_remove_request {
+ grant_ref_t gref;
+};
+
+struct fsif_rename_request {
+ uint16_t old_name_offset;
+ uint16_t new_name_offset;
+ grant_ref_t gref;
+};
+
+struct fsif_create_request {
+ int8_t directory;
+ int8_t pad;
+ int16_t pad2;
+ int32_t mode;
+ grant_ref_t gref;
+};
+
+struct fsif_list_request {
+ uint32_t offset;
+ grant_ref_t gref;
+};
+
+#define NR_FILES_SHIFT 0
+#define NR_FILES_SIZE 16 /* 16 bits for the number of files mask */
+#define NR_FILES_MASK (((1ULL << NR_FILES_SIZE) - 1) << NR_FILES_SHIFT)
+#define ERROR_SIZE 32 /* 32 bits for the error mask */
+#define ERROR_SHIFT (NR_FILES_SIZE + NR_FILES_SHIFT)
+#define ERROR_MASK (((1ULL << ERROR_SIZE) - 1) << ERROR_SHIFT)
+#define HAS_MORE_SHIFT (ERROR_SHIFT + ERROR_SIZE)
+#define HAS_MORE_FLAG (1ULL << HAS_MORE_SHIFT)
+
+struct fsif_chmod_request {
+ uint32_t fd;
+ int32_t mode;
+};
+
+struct fsif_space_request {
+ grant_ref_t gref;
+};
+
+struct fsif_sync_request {
+ uint32_t fd;
+};
+
+
+/* FS operation request */
+struct fsif_request {
+ uint8_t type; /* Type of the request */
+ uint8_t pad;
+ uint16_t id; /* Request ID, copied to the response */
+ uint32_t pad2;
+ union {
+ struct fsif_open_request fopen;
+ struct fsif_close_request fclose;
+ struct fsif_read_request fread;
+ struct fsif_write_request fwrite;
+ struct fsif_stat_request fstat;
+ struct fsif_truncate_request ftruncate;
+ struct fsif_remove_request fremove;
+ struct fsif_rename_request frename;
+ struct fsif_create_request fcreate;
+ struct fsif_list_request flist;
+ struct fsif_chmod_request fchmod;
+ struct fsif_space_request fspace;
+ struct fsif_sync_request fsync;
+ } u;
+};
+typedef struct fsif_request fsif_request_t;
+
+/* FS operation response */
+struct fsif_response {
+ uint16_t id;
+ uint16_t pad1;
+ uint32_t pad2;
+ uint64_t ret_val;
+};
+
+typedef struct fsif_response fsif_response_t;
+
+
+DEFINE_RING_TYPES(fsif, struct fsif_request, struct fsif_response);
+
+#define STATE_INITIALISED "init"
+#define STATE_READY "ready"
+
+
+
+#endif