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[Xen-devel] [PATCH] add FS backend/frontend

From: Samuel Thibault <samuel.thibault@xxxxxxxxxxxxx>

Date: Thu, 17 Jan 2008 16:24:16 +0000

Delivery-date: Thu, 17 Jan 2008 08:27:33 -0800

List-id: Xen developer discussion <xen-devel.lists.xensource.com>

Mail-followup-to: Samuel Thibault <samuel.thibault@xxxxxxxxxxxxx>, xen-devel@xxxxxxxxxxxxxxxxxxx

add FS backend/frontend Signed-off-by: Samuel Thibault <samuel.thibault@xxxxxxxxxxxxx> Signed-off-by: Grzegorz Milos <gm281@xxxxxxxxx> # HG changeset patch # User Samuel Thibault <samuel.thibault@xxxxxxxxxxxxx> # Date 1200586950 0 # Node ID b0e2c382ffb2df8485a08daf17a8e0e85436e17d # Parent c4babfc157d51322e7167a7a84e0462ea3ccedbe add FS backend/frontend diff -r c4babfc157d5 -r b0e2c382ffb2 extras/mini-os/fs-front.c --- /dev/null Thu Jan 01 00:00:00 1970 +0000 +++ b/extras/mini-os/fs-front.c Thu Jan 17 16:22:30 2008 +0000 @@ -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 -r c4babfc157d5 -r b0e2c382ffb2 extras/mini-os/include/fs.h --- /dev/null Thu Jan 01 00:00:00 1970 +0000 +++ b/extras/mini-os/include/fs.h Thu Jan 17 16:22:30 2008 +0000 @@ -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 -r c4babfc157d5 -r b0e2c382ffb2 extras/mini-os/include/types.h --- a/extras/mini-os/include/types.h Thu Jan 17 16:01:24 2008 +0000 +++ b/extras/mini-os/include/types.h Thu Jan 17 16:22:30 2008 +0000 @@ -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 -r c4babfc157d5 -r b0e2c382ffb2 extras/mini-os/kernel.c --- a/extras/mini-os/kernel.c Thu Jan 17 16:01:24 2008 +0000 +++ b/extras/mini-os/kernel.c Thu Jan 17 16:22:30 2008 +0000 @@ -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 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 -r c4babfc157d5 -r b0e2c382ffb2 tools/Makefile --- a/tools/Makefile Thu Jan 17 16:01:24 2008 +0000 +++ b/tools/Makefile Thu Jan 17 16:22:30 2008 +0000 @@ -27,6 +27,8 @@ SUBDIRS-$(PYTHON_TOOLS) += python SUBDIRS-$(PYTHON_TOOLS) += python SUBDIRS-$(PYTHON_TOOLS) += pygrub endif + +SUBDIRS-y += fs-back .PHONY: all all: check diff -r c4babfc157d5 -r b0e2c382ffb2 tools/fs-back/Makefile --- /dev/null Thu Jan 01 00:00:00 1970 +0000 +++ b/tools/fs-back/Makefile Thu Jan 17 16:22:30 2008 +0000 @@ -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 -r c4babfc157d5 -r b0e2c382ffb2 tools/fs-back/fs-backend.c --- /dev/null Thu Jan 01 00:00:00 1970 +0000 +++ b/tools/fs-back/fs-backend.c Thu Jan 17 16:22:30 2008 +0000 @@ -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 -r c4babfc157d5 -r b0e2c382ffb2 tools/fs-back/fs-backend.h --- /dev/null Thu Jan 01 00:00:00 1970 +0000 +++ b/tools/fs-back/fs-backend.h Thu Jan 17 16:22:30 2008 +0000 @@ -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 -r c4babfc157d5 -r b0e2c382ffb2 tools/fs-back/fs-ops.c --- /dev/null Thu Jan 01 00:00:00 1970 +0000 +++ b/tools/fs-back/fs-ops.c Thu Jan 17 16:22:30 2008 +0000 @@ -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 -r c4babfc157d5 -r b0e2c382ffb2 tools/fs-back/fs-xenbus.c --- /dev/null Thu Jan 01 00:00:00 1970 +0000 +++ b/tools/fs-back/fs-xenbus.c Thu Jan 17 16:22:30 2008 +0000 @@ -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 -r c4babfc157d5 -r b0e2c382ffb2 xen/include/public/io/fsif.h --- /dev/null Thu Jan 01 00:00:00 1970 +0000 +++ b/xen/include/public/io/fsif.h Thu Jan 17 16:22:30 2008 +0000 @@ -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 _______________________________________________ Xen-devel mailing list Xen-devel@xxxxxxxxxxxxxxxxxxx http://lists.xensource.com/xen-devel

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