Hi David, Today's linux-next merge of the creds tree got a conflict in net/9p/client.c between commit a3f01212456501bfc94fea289aaaee26c28f9833 ("9p: remove unnecessary prototypes") from the v9fs tree and commit 1ce149d4dcc74288936d347870d34b1781a49fad ("CRED: Wrap task credential accesses in 9P2000 filesystem") from the creds tree. The former moved the code that the latter was changing. I fixed it up (see below). -- Cheers, Stephen Rothwell sfr@xxxxxxxxxxxxxxxx http://www.canb.auug.org.au/~sfr/ diff --cc net/9p/client.c index 1807ace,aee892e..0000000 --- a/net/9p/client.c +++ b/net/9p/client.c @@@ -124,578 -124,20 +124,578 @@@ static int parse_opts(char *opts, struc return ret; } +/** + * p9_tag_alloc - lookup/allocate a request by tag + * @c: client session to lookup tag within + * @tag: numeric id for transaction + * + * this is a simple array lookup, but will grow the + * request_slots as necessary to accomodate transaction + * ids which did not previously have a slot. + * + * this code relies on the client spinlock to manage locks, its + * possible we should switch to something else, but I'd rather + * stick with something low-overhead for the common case. + * + */ + +static struct p9_req_t *p9_tag_alloc(struct p9_client *c, u16 tag) +{ + unsigned long flags; + int row, col; + struct p9_req_t *req; + + /* This looks up the original request by tag so we know which + * buffer to read the data into */ + tag++; + + if (tag >= c->max_tag) { + spin_lock_irqsave(&c->lock, flags); + /* check again since original check was outside of lock */ + while (tag >= c->max_tag) { + row = (tag / P9_ROW_MAXTAG); + c->reqs[row] = kcalloc(P9_ROW_MAXTAG, + sizeof(struct p9_req_t), GFP_ATOMIC); + + if (!c->reqs[row]) { + printk(KERN_ERR "Couldn't grow tag array\n"); + return ERR_PTR(-ENOMEM); + } + for (col = 0; col < P9_ROW_MAXTAG; col++) { + c->reqs[row][col].status = REQ_STATUS_IDLE; + c->reqs[row][col].tc = NULL; + } + c->max_tag += P9_ROW_MAXTAG; + } + spin_unlock_irqrestore(&c->lock, flags); + } + row = tag / P9_ROW_MAXTAG; + col = tag % P9_ROW_MAXTAG; + + req = &c->reqs[row][col]; + if (!req->tc) { + req->wq = kmalloc(sizeof(wait_queue_head_t), GFP_KERNEL); + if (!req->wq) { + printk(KERN_ERR "Couldn't grow tag array\n"); + return ERR_PTR(-ENOMEM); + } + init_waitqueue_head(req->wq); + req->tc = kmalloc(sizeof(struct p9_fcall)+c->msize, + GFP_KERNEL); + req->rc = kmalloc(sizeof(struct p9_fcall)+c->msize, + GFP_KERNEL); + if ((!req->tc) || (!req->rc)) { + printk(KERN_ERR "Couldn't grow tag array\n"); + kfree(req->tc); + kfree(req->rc); + return ERR_PTR(-ENOMEM); + } + req->tc->sdata = (char *) req->tc + sizeof(struct p9_fcall); + req->tc->capacity = c->msize; + req->rc->sdata = (char *) req->rc + sizeof(struct p9_fcall); + req->rc->capacity = c->msize; + } + + p9pdu_reset(req->tc); + p9pdu_reset(req->rc); + + req->flush_tag = 0; + req->tc->tag = tag-1; + req->status = REQ_STATUS_ALLOC; + + return &c->reqs[row][col]; +} + +/** + * p9_tag_lookup - lookup a request by tag + * @c: client session to lookup tag within + * @tag: numeric id for transaction + * + */ + +struct p9_req_t *p9_tag_lookup(struct p9_client *c, u16 tag) +{ + int row, col; + + /* This looks up the original request by tag so we know which + * buffer to read the data into */ + tag++; + + BUG_ON(tag >= c->max_tag); + + row = tag / P9_ROW_MAXTAG; + col = tag % P9_ROW_MAXTAG; + + return &c->reqs[row][col]; +} +EXPORT_SYMBOL(p9_tag_lookup); + +/** + * p9_tag_init - setup tags structure and contents + * @tags: tags structure from the client struct + * + * This initializes the tags structure for each client instance. + * + */ + +static int p9_tag_init(struct p9_client *c) +{ + int err = 0; + + c->tagpool = p9_idpool_create(); + if (IS_ERR(c->tagpool)) { + err = PTR_ERR(c->tagpool); + c->tagpool = NULL; + goto error; + } + + p9_idpool_get(c->tagpool); /* reserve tag 0 */ + + c->max_tag = 0; +error: + return err; +} /** - * p9_client_rpc - sends 9P request and waits until a response is available. - * The function can be interrupted. - * @c: client data - * @tc: request to be sent - * @rc: pointer where a pointer to the response is stored + * p9_tag_cleanup - cleans up tags structure and reclaims resources + * @tags: tags structure from the client struct + * + * This frees resources associated with the tags structure + * */ +static void p9_tag_cleanup(struct p9_client *c) +{ + int row, col; + + /* check to insure all requests are idle */ + for (row = 0; row < (c->max_tag/P9_ROW_MAXTAG); row++) { + for (col = 0; col < P9_ROW_MAXTAG; col++) { + if (c->reqs[row][col].status != REQ_STATUS_IDLE) { + P9_DPRINTK(P9_DEBUG_MUX, + "Attempting to cleanup non-free tag %d,%d\n", + row, col); + /* TODO: delay execution of cleanup */ + return; + } + } + } + + if (c->tagpool) + p9_idpool_destroy(c->tagpool); + + /* free requests associated with tags */ + for (row = 0; row < (c->max_tag/P9_ROW_MAXTAG); row++) { + for (col = 0; col < P9_ROW_MAXTAG; col++) { + kfree(c->reqs[row][col].wq); + kfree(c->reqs[row][col].tc); + kfree(c->reqs[row][col].rc); + } + kfree(c->reqs[row]); + } + c->max_tag = 0; +} + +/** + * p9_free_req - free a request and clean-up as necessary + * c: client state + * r: request to release + * + */ + +static void p9_free_req(struct p9_client *c, struct p9_req_t *r) +{ + int tag = r->tc->tag; + P9_DPRINTK(P9_DEBUG_MUX, "clnt %p req %p tag: %d\n", c, r, tag); + + r->status = REQ_STATUS_IDLE; + if (tag != P9_NOTAG && p9_idpool_check(tag, c->tagpool)) + p9_idpool_put(tag, c->tagpool); + + /* if this was a flush request we have to free response fcall */ + if (r->rc->id == P9_RFLUSH) { + kfree(r->tc); + kfree(r->rc); + } +} + +/** + * p9_client_cb - call back from transport to client + * c: client state + * req: request received + * + */ +void p9_client_cb(struct p9_client *c, struct p9_req_t *req) +{ + struct p9_req_t *other_req; + unsigned long flags; + + P9_DPRINTK(P9_DEBUG_MUX, " tag %d\n", req->tc->tag); + + if (req->status == REQ_STATUS_ERROR) + wake_up(req->wq); + + if (req->flush_tag) { /* flush receive path */ + P9_DPRINTK(P9_DEBUG_9P, "<<< RFLUSH %d\n", req->tc->tag); + spin_lock_irqsave(&c->lock, flags); + other_req = p9_tag_lookup(c, req->flush_tag); + if (other_req->status != REQ_STATUS_FLSH) /* stale flush */ + spin_unlock_irqrestore(&c->lock, flags); + else { + other_req->status = REQ_STATUS_FLSHD; + spin_unlock_irqrestore(&c->lock, flags); + wake_up(other_req->wq); + } + p9_free_req(c, req); + } else { /* normal receive path */ + P9_DPRINTK(P9_DEBUG_MUX, "normal: tag %d\n", req->tc->tag); + spin_lock_irqsave(&c->lock, flags); + if (req->status != REQ_STATUS_FLSHD) + req->status = REQ_STATUS_RCVD; + spin_unlock_irqrestore(&c->lock, flags); + wake_up(req->wq); + P9_DPRINTK(P9_DEBUG_MUX, "wakeup: %d\n", req->tc->tag); + } +} +EXPORT_SYMBOL(p9_client_cb); + +/** + * p9_parse_header - parse header arguments out of a packet + * @pdu: packet to parse + * @size: size of packet + * @type: type of request + * @tag: tag of packet + * @rewind: set if we need to rewind offset afterwards + */ + int -p9_client_rpc(struct p9_client *c, struct p9_fcall *tc, - struct p9_fcall **rc) +p9_parse_header(struct p9_fcall *pdu, int32_t *size, int8_t *type, int16_t *tag, + int rewind) { - return c->trans->rpc(c->trans, tc, rc); + int8_t r_type; + int16_t r_tag; + int32_t r_size; + int offset = pdu->offset; + int err; + + pdu->offset = 0; + if (pdu->size == 0) + pdu->size = 7; + + err = p9pdu_readf(pdu, 0, "dbw", &r_size, &r_type, &r_tag); + if (err) + goto rewind_and_exit; + + pdu->size = r_size; + pdu->id = r_type; + pdu->tag = r_tag; + + P9_DPRINTK(P9_DEBUG_9P, "<<< size=%d type: %d tag: %d\n", pdu->size, + pdu->id, pdu->tag); + + if (type) + *type = r_type; + if (tag) + *tag = r_tag; + if (size) + *size = r_size; + + +rewind_and_exit: + if (rewind) + pdu->offset = offset; + return err; } +EXPORT_SYMBOL(p9_parse_header); + +/** + * p9_check_errors - check 9p packet for error return and process it + * @c: current client instance + * @req: request to parse and check for error conditions + * + * returns error code if one is discovered, otherwise returns 0 + * + * this will have to be more complicated if we have multiple + * error packet types + */ + +static int p9_check_errors(struct p9_client *c, struct p9_req_t *req) +{ + int8_t type; + int err; + + err = p9_parse_header(req->rc, NULL, &type, NULL, 0); + if (err) { + P9_DPRINTK(P9_DEBUG_ERROR, "couldn't parse header %d\n", err); + return err; + } + + if (type == P9_RERROR) { + int ecode; + char *ename; + + err = p9pdu_readf(req->rc, c->dotu, "s?d", &ename, &ecode); + if (err) { + P9_DPRINTK(P9_DEBUG_ERROR, "couldn't parse error%d\n", + err); + return err; + } + + if (c->dotu) + err = -ecode; + + if (!err) { + err = p9_errstr2errno(ename, strlen(ename)); + + /* string match failed */ + if (!err) + err = -ESERVERFAULT; + } + + P9_DPRINTK(P9_DEBUG_9P, "<<< RERROR (%d) %s\n", -ecode, ename); + + kfree(ename); + } else + err = 0; + + return err; +} + +/** + * p9_client_flush - flush (cancel) a request + * c: client state + * req: request to cancel + * + * This sents a flush for a particular requests and links + * the flush request to the original request. The current + * code only supports a single flush request although the protocol + * allows for multiple flush requests to be sent for a single request. + * + */ + +static int p9_client_flush(struct p9_client *c, struct p9_req_t *oldreq) +{ + struct p9_req_t *req; + int16_t oldtag; + int err; + + err = p9_parse_header(oldreq->tc, NULL, NULL, &oldtag, 1); + if (err) + return err; + + P9_DPRINTK(P9_DEBUG_9P, ">>> TFLUSH tag %d\n", oldtag); + + req = p9_client_rpc(c, P9_TFLUSH, "w", oldtag); + if (IS_ERR(req)) + return PTR_ERR(req); + + req->flush_tag = oldtag; + + /* we don't free anything here because RPC isn't complete */ + return 0; +} + +/** + * p9_client_rpc - issue a request and wait for a response + * @c: client session + * @type: type of request + * @fmt: protocol format string (see protocol.c) + * + * Returns request structure (which client must free using p9_free_req) + */ + +static struct p9_req_t * +p9_client_rpc(struct p9_client *c, int8_t type, const char *fmt, ...) +{ + va_list ap; + int tag, err; + struct p9_req_t *req; + unsigned long flags; + int sigpending; + int flushed = 0; + + P9_DPRINTK(P9_DEBUG_MUX, "client %p op %d\n", c, type); + + if (c->status != Connected) + return ERR_PTR(-EIO); + + if (signal_pending(current)) { + sigpending = 1; + clear_thread_flag(TIF_SIGPENDING); + } else + sigpending = 0; + + tag = P9_NOTAG; + if (type != P9_TVERSION) { + tag = p9_idpool_get(c->tagpool); + if (tag < 0) + return ERR_PTR(-ENOMEM); + } + + req = p9_tag_alloc(c, tag); + if (IS_ERR(req)) + return req; + + /* marshall the data */ + p9pdu_prepare(req->tc, tag, type); + va_start(ap, fmt); + err = p9pdu_vwritef(req->tc, c->dotu, fmt, ap); + va_end(ap); + p9pdu_finalize(req->tc); + + err = c->trans_mod->request(c, req); + if (err < 0) { + c->status = Disconnected; + goto reterr; + } + + /* if it was a flush we just transmitted, return our tag */ + if (type == P9_TFLUSH) + return req; +again: + P9_DPRINTK(P9_DEBUG_MUX, "wait %p tag: %d\n", req->wq, tag); + err = wait_event_interruptible(*req->wq, + req->status >= REQ_STATUS_RCVD); + P9_DPRINTK(P9_DEBUG_MUX, "wait %p tag: %d returned %d (flushed=%d)\n", + req->wq, tag, err, flushed); + + if (req->status == REQ_STATUS_ERROR) { + P9_DPRINTK(P9_DEBUG_ERROR, "req_status error %d\n", req->t_err); + err = req->t_err; + } else if (err == -ERESTARTSYS && flushed) { + P9_DPRINTK(P9_DEBUG_MUX, "flushed - going again\n"); + goto again; + } else if (req->status == REQ_STATUS_FLSHD) { + P9_DPRINTK(P9_DEBUG_MUX, "flushed - erestartsys\n"); + err = -ERESTARTSYS; + } + + if ((err == -ERESTARTSYS) && (c->status == Connected) && (!flushed)) { + P9_DPRINTK(P9_DEBUG_MUX, "flushing\n"); + spin_lock_irqsave(&c->lock, flags); + if (req->status == REQ_STATUS_SENT) + req->status = REQ_STATUS_FLSH; + spin_unlock_irqrestore(&c->lock, flags); + sigpending = 1; + flushed = 1; + clear_thread_flag(TIF_SIGPENDING); + + if (c->trans_mod->cancel(c, req)) { + err = p9_client_flush(c, req); + if (err == 0) + goto again; + } + } + + if (sigpending) { + spin_lock_irqsave(¤t->sighand->siglock, flags); + recalc_sigpending(); + spin_unlock_irqrestore(¤t->sighand->siglock, flags); + } + + if (err < 0) + goto reterr; + + err = p9_check_errors(c, req); + if (!err) { + P9_DPRINTK(P9_DEBUG_MUX, "exit: client %p op %d\n", c, type); + return req; + } + +reterr: + P9_DPRINTK(P9_DEBUG_MUX, "exit: client %p op %d error: %d\n", c, type, + err); + p9_free_req(c, req); + return ERR_PTR(err); +} + +static struct p9_fid *p9_fid_create(struct p9_client *clnt) +{ + int err; + struct p9_fid *fid; + + P9_DPRINTK(P9_DEBUG_FID, "clnt %p\n", clnt); + fid = kmalloc(sizeof(struct p9_fid), GFP_KERNEL); + if (!fid) + return ERR_PTR(-ENOMEM); + + fid->fid = p9_idpool_get(clnt->fidpool); + if (fid->fid < 0) { + err = -ENOSPC; + goto error; + } + + memset(&fid->qid, 0, sizeof(struct p9_qid)); + fid->mode = -1; + fid->rdir_fpos = 0; - fid->uid = current->fsuid; ++ fid->uid = current_fsuid(); + fid->clnt = clnt; + fid->aux = NULL; + + spin_lock(&clnt->lock); + list_add(&fid->flist, &clnt->fidlist); + spin_unlock(&clnt->lock); + + return fid; + +error: + kfree(fid); + return ERR_PTR(err); +} + +static void p9_fid_destroy(struct p9_fid *fid) +{ + struct p9_client *clnt; + + P9_DPRINTK(P9_DEBUG_FID, "fid %d\n", fid->fid); + clnt = fid->clnt; + p9_idpool_put(fid->fid, clnt->fidpool); + spin_lock(&clnt->lock); + list_del(&fid->flist); + spin_unlock(&clnt->lock); + kfree(fid); +} + +static int p9_client_version(struct p9_client *c) +{ + int err = 0; + struct p9_req_t *req; + char *version; + int msize; + + P9_DPRINTK(P9_DEBUG_9P, ">>> TVERSION msize %d extended %d\n", + c->msize, c->dotu); + req = p9_client_rpc(c, P9_TVERSION, "ds", c->msize, + c->dotu ? "9P2000.u" : "9P2000"); + if (IS_ERR(req)) + return PTR_ERR(req); + + err = p9pdu_readf(req->rc, c->dotu, "ds", &msize, &version); + if (err) { + P9_DPRINTK(P9_DEBUG_9P, "version error %d\n", err); + p9pdu_dump(1, req->rc); + goto error; + } + + P9_DPRINTK(P9_DEBUG_9P, "<<< RVERSION msize %d %s\n", msize, version); + if (!memcmp(version, "9P2000.u", 8)) + c->dotu = 1; + else if (!memcmp(version, "9P2000", 6)) + c->dotu = 0; + else { + err = -EREMOTEIO; + goto error; + } + + if (msize < c->msize) + c->msize = msize; + +error: + kfree(version); + p9_free_req(c, req); + + return err; +} +EXPORT_SYMBOL(p9_client_version); struct p9_client *p9_client_create(const char *dev_name, char *options) { -- To unsubscribe from this list: send the line "unsubscribe linux-next" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html