diff options
Diffstat (limited to 'net/9p/client.c')
| -rw-r--r-- | net/9p/client.c | 2276 |
1 files changed, 2276 insertions, 0 deletions
diff --git a/net/9p/client.c b/net/9p/client.c new file mode 100644 index 000000000..84b93b04d --- /dev/null +++ b/net/9p/client.c @@ -0,0 +1,2276 @@ +// SPDX-License-Identifier: GPL-2.0-only +/* + * 9P Client + * + * Copyright (C) 2008 by Eric Van Hensbergen <ericvh@gmail.com> + * Copyright (C) 2007 by Latchesar Ionkov <lucho@ionkov.net> + */ + +#define pr_fmt(fmt) KBUILD_MODNAME ": " fmt + +#include <linux/module.h> +#include <linux/errno.h> +#include <linux/fs.h> +#include <linux/poll.h> +#include <linux/idr.h> +#include <linux/mutex.h> +#include <linux/slab.h> +#include <linux/sched/signal.h> +#include <linux/uaccess.h> +#include <linux/uio.h> +#include <net/9p/9p.h> +#include <linux/parser.h> +#include <linux/seq_file.h> +#include <net/9p/client.h> +#include <net/9p/transport.h> +#include "protocol.h" + +#define CREATE_TRACE_POINTS +#include <trace/events/9p.h> + +#define DEFAULT_MSIZE (128 * 1024) + +/* Client Option Parsing (code inspired by NFS code) + * - a little lazy - parse all client options + */ + +enum { + Opt_msize, + Opt_trans, + Opt_legacy, + Opt_version, + Opt_err, +}; + +static const match_table_t tokens = { + {Opt_msize, "msize=%u"}, + {Opt_legacy, "noextend"}, + {Opt_trans, "trans=%s"}, + {Opt_version, "version=%s"}, + {Opt_err, NULL}, +}; + +inline int p9_is_proto_dotl(struct p9_client *clnt) +{ + return clnt->proto_version == p9_proto_2000L; +} +EXPORT_SYMBOL(p9_is_proto_dotl); + +inline int p9_is_proto_dotu(struct p9_client *clnt) +{ + return clnt->proto_version == p9_proto_2000u; +} +EXPORT_SYMBOL(p9_is_proto_dotu); + +int p9_show_client_options(struct seq_file *m, struct p9_client *clnt) +{ + if (clnt->msize != DEFAULT_MSIZE) + seq_printf(m, ",msize=%u", clnt->msize); + seq_printf(m, ",trans=%s", clnt->trans_mod->name); + + switch (clnt->proto_version) { + case p9_proto_legacy: + seq_puts(m, ",noextend"); + break; + case p9_proto_2000u: + seq_puts(m, ",version=9p2000.u"); + break; + case p9_proto_2000L: + /* Default */ + break; + } + + if (clnt->trans_mod->show_options) + return clnt->trans_mod->show_options(m, clnt); + return 0; +} +EXPORT_SYMBOL(p9_show_client_options); + +/* Some error codes are taken directly from the server replies, + * make sure they are valid. + */ +static int safe_errno(int err) +{ + if (err > 0 || err < -MAX_ERRNO) { + p9_debug(P9_DEBUG_ERROR, "Invalid error code %d\n", err); + return -EPROTO; + } + return err; +} + +/* Interpret mount option for protocol version */ +static int get_protocol_version(char *s) +{ + int version = -EINVAL; + + if (!strcmp(s, "9p2000")) { + version = p9_proto_legacy; + p9_debug(P9_DEBUG_9P, "Protocol version: Legacy\n"); + } else if (!strcmp(s, "9p2000.u")) { + version = p9_proto_2000u; + p9_debug(P9_DEBUG_9P, "Protocol version: 9P2000.u\n"); + } else if (!strcmp(s, "9p2000.L")) { + version = p9_proto_2000L; + p9_debug(P9_DEBUG_9P, "Protocol version: 9P2000.L\n"); + } else { + pr_info("Unknown protocol version %s\n", s); + } + + return version; +} + +/** + * parse_opts - parse mount options into client structure + * @opts: options string passed from mount + * @clnt: existing v9fs client information + * + * Return 0 upon success, -ERRNO upon failure + */ + +static int parse_opts(char *opts, struct p9_client *clnt) +{ + char *options, *tmp_options; + char *p; + substring_t args[MAX_OPT_ARGS]; + int option; + char *s; + int ret = 0; + + clnt->proto_version = p9_proto_2000L; + clnt->msize = DEFAULT_MSIZE; + + if (!opts) + return 0; + + tmp_options = kstrdup(opts, GFP_KERNEL); + if (!tmp_options) + return -ENOMEM; + options = tmp_options; + + while ((p = strsep(&options, ",")) != NULL) { + int token, r; + + if (!*p) + continue; + token = match_token(p, tokens, args); + switch (token) { + case Opt_msize: + r = match_int(&args[0], &option); + if (r < 0) { + p9_debug(P9_DEBUG_ERROR, + "integer field, but no integer?\n"); + ret = r; + continue; + } + if (option < 4096) { + p9_debug(P9_DEBUG_ERROR, + "msize should be at least 4k\n"); + ret = -EINVAL; + continue; + } + clnt->msize = option; + break; + case Opt_trans: + s = match_strdup(&args[0]); + if (!s) { + ret = -ENOMEM; + p9_debug(P9_DEBUG_ERROR, + "problem allocating copy of trans arg\n"); + goto free_and_return; + } + + v9fs_put_trans(clnt->trans_mod); + clnt->trans_mod = v9fs_get_trans_by_name(s); + if (!clnt->trans_mod) { + pr_info("Could not find request transport: %s\n", + s); + ret = -EINVAL; + } + kfree(s); + break; + case Opt_legacy: + clnt->proto_version = p9_proto_legacy; + break; + case Opt_version: + s = match_strdup(&args[0]); + if (!s) { + ret = -ENOMEM; + p9_debug(P9_DEBUG_ERROR, + "problem allocating copy of version arg\n"); + goto free_and_return; + } + r = get_protocol_version(s); + if (r < 0) + ret = r; + else + clnt->proto_version = r; + kfree(s); + break; + default: + continue; + } + } + +free_and_return: + if (ret) + v9fs_put_trans(clnt->trans_mod); + kfree(tmp_options); + return ret; +} + +static int p9_fcall_init(struct p9_client *c, struct p9_fcall *fc, + int alloc_msize) +{ + if (likely(c->fcall_cache) && alloc_msize == c->msize) { + fc->sdata = kmem_cache_alloc(c->fcall_cache, GFP_NOFS); + fc->cache = c->fcall_cache; + } else { + fc->sdata = kmalloc(alloc_msize, GFP_NOFS); + fc->cache = NULL; + } + if (!fc->sdata) + return -ENOMEM; + fc->capacity = alloc_msize; + return 0; +} + +void p9_fcall_fini(struct p9_fcall *fc) +{ + /* sdata can be NULL for interrupted requests in trans_rdma, + * and kmem_cache_free does not do NULL-check for us + */ + if (unlikely(!fc->sdata)) + return; + + if (fc->cache) + kmem_cache_free(fc->cache, fc->sdata); + else + kfree(fc->sdata); +} +EXPORT_SYMBOL(p9_fcall_fini); + +static struct kmem_cache *p9_req_cache; + +/** + * p9_tag_alloc - Allocate a new request. + * @c: Client session. + * @type: Transaction type. + * @t_size: Buffer size for holding this request + * (automatic calculation by format template if 0). + * @r_size: Buffer size for holding server's reply on this request + * (automatic calculation by format template if 0). + * @fmt: Format template for assembling 9p request message + * (see p9pdu_vwritef). + * @ap: Variable arguments to be fed to passed format template + * (see p9pdu_vwritef). + * + * Context: Process context. + * Return: Pointer to new request. + */ +static struct p9_req_t * +p9_tag_alloc(struct p9_client *c, int8_t type, uint t_size, uint r_size, + const char *fmt, va_list ap) +{ + struct p9_req_t *req = kmem_cache_alloc(p9_req_cache, GFP_NOFS); + int alloc_tsize; + int alloc_rsize; + int tag; + va_list apc; + + va_copy(apc, ap); + alloc_tsize = min_t(size_t, c->msize, + t_size ?: p9_msg_buf_size(c, type, fmt, apc)); + va_end(apc); + + alloc_rsize = min_t(size_t, c->msize, + r_size ?: p9_msg_buf_size(c, type + 1, fmt, ap)); + + if (!req) + return ERR_PTR(-ENOMEM); + + if (p9_fcall_init(c, &req->tc, alloc_tsize)) + goto free_req; + if (p9_fcall_init(c, &req->rc, alloc_rsize)) + goto free; + + p9pdu_reset(&req->tc); + p9pdu_reset(&req->rc); + req->t_err = 0; + req->status = REQ_STATUS_ALLOC; + /* refcount needs to be set to 0 before inserting into the idr + * so p9_tag_lookup does not accept a request that is not fully + * initialized. refcount_set to 2 below will mark request ready. + */ + refcount_set(&req->refcount, 0); + init_waitqueue_head(&req->wq); + INIT_LIST_HEAD(&req->req_list); + + idr_preload(GFP_NOFS); + spin_lock_irq(&c->lock); + if (type == P9_TVERSION) + tag = idr_alloc(&c->reqs, req, P9_NOTAG, P9_NOTAG + 1, + GFP_NOWAIT); + else + tag = idr_alloc(&c->reqs, req, 0, P9_NOTAG, GFP_NOWAIT); + req->tc.tag = tag; + spin_unlock_irq(&c->lock); + idr_preload_end(); + if (tag < 0) + goto free; + + /* Init ref to two because in the general case there is one ref + * that is put asynchronously by a writer thread, one ref + * temporarily given by p9_tag_lookup and put by p9_client_cb + * in the recv thread, and one ref put by p9_req_put in the + * main thread. The only exception is virtio that does not use + * p9_tag_lookup but does not have a writer thread either + * (the write happens synchronously in the request/zc_request + * callback), so p9_client_cb eats the second ref there + * as the pointer is duplicated directly by virtqueue_add_sgs() + */ + refcount_set(&req->refcount, 2); + + return req; + +free: + p9_fcall_fini(&req->tc); + p9_fcall_fini(&req->rc); +free_req: + kmem_cache_free(p9_req_cache, req); + return ERR_PTR(-ENOMEM); +} + +/** + * p9_tag_lookup - Look up a request by tag. + * @c: Client session. + * @tag: Transaction ID. + * + * Context: Any context. + * Return: A request, or %NULL if there is no request with that tag. + */ +struct p9_req_t *p9_tag_lookup(struct p9_client *c, u16 tag) +{ + struct p9_req_t *req; + + rcu_read_lock(); +again: + req = idr_find(&c->reqs, tag); + if (req) { + /* We have to be careful with the req found under rcu_read_lock + * Thanks to SLAB_TYPESAFE_BY_RCU we can safely try to get the + * ref again without corrupting other data, then check again + * that the tag matches once we have the ref + */ + if (!p9_req_try_get(req)) + goto again; + if (req->tc.tag != tag) { + p9_req_put(c, req); + goto again; + } + } + rcu_read_unlock(); + + return req; +} +EXPORT_SYMBOL(p9_tag_lookup); + +/** + * p9_tag_remove - Remove a tag. + * @c: Client session. + * @r: Request of reference. + * + * Context: Any context. + */ +static void p9_tag_remove(struct p9_client *c, struct p9_req_t *r) +{ + unsigned long flags; + u16 tag = r->tc.tag; + + p9_debug(P9_DEBUG_MUX, "freeing clnt %p req %p tag: %d\n", c, r, tag); + spin_lock_irqsave(&c->lock, flags); + idr_remove(&c->reqs, tag); + spin_unlock_irqrestore(&c->lock, flags); +} + +int p9_req_put(struct p9_client *c, struct p9_req_t *r) +{ + if (refcount_dec_and_test(&r->refcount)) { + p9_tag_remove(c, r); + + p9_fcall_fini(&r->tc); + p9_fcall_fini(&r->rc); + kmem_cache_free(p9_req_cache, r); + return 1; + } + return 0; +} +EXPORT_SYMBOL(p9_req_put); + +/** + * p9_tag_cleanup - cleans up tags structure and reclaims resources + * @c: v9fs client struct + * + * This frees resources associated with the tags structure + * + */ +static void p9_tag_cleanup(struct p9_client *c) +{ + struct p9_req_t *req; + int id; + + rcu_read_lock(); + idr_for_each_entry(&c->reqs, req, id) { + pr_info("Tag %d still in use\n", id); + if (p9_req_put(c, req) == 0) + pr_warn("Packet with tag %d has still references", + req->tc.tag); + } + rcu_read_unlock(); +} + +/** + * p9_client_cb - call back from transport to client + * @c: client state + * @req: request received + * @status: request status, one of REQ_STATUS_* + * + */ +void p9_client_cb(struct p9_client *c, struct p9_req_t *req, int status) +{ + p9_debug(P9_DEBUG_MUX, " tag %d\n", req->tc.tag); + + /* This barrier is needed to make sure any change made to req before + * the status change is visible to another thread + */ + smp_wmb(); + WRITE_ONCE(req->status, status); + + wake_up(&req->wq); + p9_debug(P9_DEBUG_MUX, "wakeup: %d\n", req->tc.tag); + p9_req_put(c, req); +} +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_parse_header(struct p9_fcall *pdu, int32_t *size, int8_t *type, + int16_t *tag, int rewind) +{ + s8 r_type; + s16 r_tag; + s32 r_size; + int offset = pdu->offset; + int err; + + pdu->offset = 0; + + err = p9pdu_readf(pdu, 0, "dbw", &r_size, &r_type, &r_tag); + if (err) + goto rewind_and_exit; + + if (type) + *type = r_type; + if (tag) + *tag = r_tag; + if (size) + *size = r_size; + + if (pdu->size != r_size || r_size < 7) { + err = -EINVAL; + goto rewind_and_exit; + } + + pdu->id = r_type; + pdu->tag = r_tag; + + p9_debug(P9_DEBUG_9P, "<<< size=%d type: %d tag: %d\n", + pdu->size, pdu->id, pdu->tag); + +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) +{ + s8 type; + int err; + int ecode; + + err = p9_parse_header(&req->rc, NULL, &type, NULL, 0); + if (req->rc.size >= c->msize) { + p9_debug(P9_DEBUG_ERROR, + "requested packet size too big: %d\n", + req->rc.size); + return -EIO; + } + /* dump the response from server + * This should be after check errors which poplulate pdu_fcall. + */ + trace_9p_protocol_dump(c, &req->rc); + if (err) { + p9_debug(P9_DEBUG_ERROR, "couldn't parse header %d\n", err); + return err; + } + if (type != P9_RERROR && type != P9_RLERROR) + return 0; + + if (!p9_is_proto_dotl(c)) { + char *ename = NULL; + + err = p9pdu_readf(&req->rc, c->proto_version, "s?d", + &ename, &ecode); + if (err) { + kfree(ename); + goto out_err; + } + + if (p9_is_proto_dotu(c) && ecode < 512) + err = -ecode; + + if (!err) { + err = p9_errstr2errno(ename, strlen(ename)); + + p9_debug(P9_DEBUG_9P, "<<< RERROR (%d) %s\n", + -ecode, ename); + } + kfree(ename); + } else { + err = p9pdu_readf(&req->rc, c->proto_version, "d", &ecode); + if (err) + goto out_err; + err = -ecode; + + p9_debug(P9_DEBUG_9P, "<<< RLERROR (%d)\n", -ecode); + } + + return err; + +out_err: + p9_debug(P9_DEBUG_ERROR, "couldn't parse error%d\n", err); + + return err; +} + +static struct p9_req_t * +p9_client_rpc(struct p9_client *c, int8_t type, const char *fmt, ...); + +/** + * p9_client_flush - flush (cancel) a request + * @c: client state + * @oldreq: request to cancel + * + * This sents a flush for a particular request 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; + s16 oldtag; + int err; + + err = p9_parse_header(&oldreq->tc, NULL, NULL, &oldtag, 1); + if (err) + return err; + + p9_debug(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); + + /* if we haven't received a response for oldreq, + * remove it from the list + */ + if (READ_ONCE(oldreq->status) == REQ_STATUS_SENT) { + if (c->trans_mod->cancelled) + c->trans_mod->cancelled(c, oldreq); + } + + p9_req_put(c, req); + return 0; +} + +static struct p9_req_t *p9_client_prepare_req(struct p9_client *c, + int8_t type, uint t_size, uint r_size, + const char *fmt, va_list ap) +{ + int err; + struct p9_req_t *req; + va_list apc; + + p9_debug(P9_DEBUG_MUX, "client %p op %d\n", c, type); + + /* we allow for any status other than disconnected */ + if (c->status == Disconnected) + return ERR_PTR(-EIO); + + /* if status is begin_disconnected we allow only clunk request */ + if (c->status == BeginDisconnect && type != P9_TCLUNK) + return ERR_PTR(-EIO); + + va_copy(apc, ap); + req = p9_tag_alloc(c, type, t_size, r_size, fmt, apc); + va_end(apc); + if (IS_ERR(req)) + return req; + + /* marshall the data */ + p9pdu_prepare(&req->tc, req->tc.tag, type); + err = p9pdu_vwritef(&req->tc, c->proto_version, fmt, ap); + if (err) + goto reterr; + p9pdu_finalize(c, &req->tc); + trace_9p_client_req(c, type, req->tc.tag); + return req; +reterr: + p9_req_put(c, req); + /* We have to put also the 2nd reference as it won't be used */ + p9_req_put(c, req); + return ERR_PTR(err); +} + +/** + * 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_req_put) + */ + +static struct p9_req_t * +p9_client_rpc(struct p9_client *c, int8_t type, const char *fmt, ...) +{ + va_list ap; + int sigpending, err; + unsigned long flags; + struct p9_req_t *req; + /* Passing zero for tsize/rsize to p9_client_prepare_req() tells it to + * auto determine an appropriate (small) request/response size + * according to actual message data being sent. Currently RDMA + * transport is excluded from this response message size optimization, + * as it would not cope with it, due to its pooled response buffers + * (using an optimized request size for RDMA as well though). + */ + const uint tsize = 0; + const uint rsize = c->trans_mod->pooled_rbuffers ? c->msize : 0; + + va_start(ap, fmt); + req = p9_client_prepare_req(c, type, tsize, rsize, fmt, ap); + va_end(ap); + if (IS_ERR(req)) + return req; + + if (signal_pending(current)) { + sigpending = 1; + clear_thread_flag(TIF_SIGPENDING); + } else { + sigpending = 0; + } + + err = c->trans_mod->request(c, req); + if (err < 0) { + /* write won't happen */ + p9_req_put(c, req); + if (err != -ERESTARTSYS && err != -EFAULT) + c->status = Disconnected; + goto recalc_sigpending; + } +again: + /* Wait for the response */ + err = wait_event_killable(req->wq, + READ_ONCE(req->status) >= REQ_STATUS_RCVD); + + /* Make sure our req is coherent with regard to updates in other + * threads - echoes to wmb() in the callback + */ + smp_rmb(); + + if (err == -ERESTARTSYS && c->status == Connected && + type == P9_TFLUSH) { + sigpending = 1; + clear_thread_flag(TIF_SIGPENDING); + goto again; + } + + if (READ_ONCE(req->status) == REQ_STATUS_ERROR) { + p9_debug(P9_DEBUG_ERROR, "req_status error %d\n", req->t_err); + err = req->t_err; + } + if (err == -ERESTARTSYS && c->status == Connected) { + p9_debug(P9_DEBUG_MUX, "flushing\n"); + sigpending = 1; + clear_thread_flag(TIF_SIGPENDING); + + if (c->trans_mod->cancel(c, req)) + p9_client_flush(c, req); + + /* if we received the response anyway, don't signal error */ + if (READ_ONCE(req->status) == REQ_STATUS_RCVD) + err = 0; + } +recalc_sigpending: + 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); + trace_9p_client_res(c, type, req->rc.tag, err); + if (!err) + return req; +reterr: + p9_req_put(c, req); + return ERR_PTR(safe_errno(err)); +} + +/** + * p9_client_zc_rpc - issue a request and wait for a response + * @c: client session + * @type: type of request + * @uidata: destination for zero copy read + * @uodata: source for zero copy write + * @inlen: read buffer size + * @olen: write buffer size + * @in_hdrlen: reader header size, This is the size of response protocol data + * @fmt: protocol format string (see protocol.c) + * + * Returns request structure (which client must free using p9_req_put) + */ +static struct p9_req_t *p9_client_zc_rpc(struct p9_client *c, int8_t type, + struct iov_iter *uidata, + struct iov_iter *uodata, + int inlen, int olen, int in_hdrlen, + const char *fmt, ...) +{ + va_list ap; + int sigpending, err; + unsigned long flags; + struct p9_req_t *req; + + va_start(ap, fmt); + /* We allocate a inline protocol data of only 4k bytes. + * The actual content is passed in zero-copy fashion. + */ + req = p9_client_prepare_req(c, type, P9_ZC_HDR_SZ, P9_ZC_HDR_SZ, fmt, ap); + va_end(ap); + if (IS_ERR(req)) + return req; + + if (signal_pending(current)) { + sigpending = 1; + clear_thread_flag(TIF_SIGPENDING); + } else { + sigpending = 0; + } + + err = c->trans_mod->zc_request(c, req, uidata, uodata, + inlen, olen, in_hdrlen); + if (err < 0) { + if (err == -EIO) + c->status = Disconnected; + if (err != -ERESTARTSYS) + goto recalc_sigpending; + } + if (READ_ONCE(req->status) == REQ_STATUS_ERROR) { + p9_debug(P9_DEBUG_ERROR, "req_status error %d\n", req->t_err); + err = req->t_err; + } + if (err == -ERESTARTSYS && c->status == Connected) { + p9_debug(P9_DEBUG_MUX, "flushing\n"); + sigpending = 1; + clear_thread_flag(TIF_SIGPENDING); + + if (c->trans_mod->cancel(c, req)) + p9_client_flush(c, req); + + /* if we received the response anyway, don't signal error */ + if (READ_ONCE(req->status) == REQ_STATUS_RCVD) + err = 0; + } +recalc_sigpending: + 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); + trace_9p_client_res(c, type, req->rc.tag, err); + if (!err) + return req; +reterr: + p9_req_put(c, req); + return ERR_PTR(safe_errno(err)); +} + +static struct p9_fid *p9_fid_create(struct p9_client *clnt) +{ + int ret; + struct p9_fid *fid; + + p9_debug(P9_DEBUG_FID, "clnt %p\n", clnt); + fid = kzalloc(sizeof(*fid), GFP_KERNEL); + if (!fid) + return NULL; + + fid->mode = -1; + fid->uid = current_fsuid(); + fid->clnt = clnt; + refcount_set(&fid->count, 1); + + idr_preload(GFP_KERNEL); + spin_lock_irq(&clnt->lock); + ret = idr_alloc_u32(&clnt->fids, fid, &fid->fid, P9_NOFID - 1, + GFP_NOWAIT); + spin_unlock_irq(&clnt->lock); + idr_preload_end(); + if (!ret) { + trace_9p_fid_ref(fid, P9_FID_REF_CREATE); + return fid; + } + + kfree(fid); + return NULL; +} + +static void p9_fid_destroy(struct p9_fid *fid) +{ + struct p9_client *clnt; + unsigned long flags; + + p9_debug(P9_DEBUG_FID, "fid %d\n", fid->fid); + trace_9p_fid_ref(fid, P9_FID_REF_DESTROY); + clnt = fid->clnt; + spin_lock_irqsave(&clnt->lock, flags); + idr_remove(&clnt->fids, fid->fid); + spin_unlock_irqrestore(&clnt->lock, flags); + kfree(fid->rdir); + kfree(fid); +} + +/* We also need to export tracepoint symbols for tracepoint_enabled() */ +EXPORT_TRACEPOINT_SYMBOL(9p_fid_ref); + +void do_trace_9p_fid_get(struct p9_fid *fid) +{ + trace_9p_fid_ref(fid, P9_FID_REF_GET); +} +EXPORT_SYMBOL(do_trace_9p_fid_get); + +void do_trace_9p_fid_put(struct p9_fid *fid) +{ + trace_9p_fid_ref(fid, P9_FID_REF_PUT); +} +EXPORT_SYMBOL(do_trace_9p_fid_put); + +static int p9_client_version(struct p9_client *c) +{ + int err = 0; + struct p9_req_t *req; + char *version = NULL; + int msize; + + p9_debug(P9_DEBUG_9P, ">>> TVERSION msize %d protocol %d\n", + c->msize, c->proto_version); + + switch (c->proto_version) { + case p9_proto_2000L: + req = p9_client_rpc(c, P9_TVERSION, "ds", + c->msize, "9P2000.L"); + break; + case p9_proto_2000u: + req = p9_client_rpc(c, P9_TVERSION, "ds", + c->msize, "9P2000.u"); + break; + case p9_proto_legacy: + req = p9_client_rpc(c, P9_TVERSION, "ds", + c->msize, "9P2000"); + break; + default: + return -EINVAL; + } + + if (IS_ERR(req)) + return PTR_ERR(req); + + err = p9pdu_readf(&req->rc, c->proto_version, "ds", &msize, &version); + if (err) { + p9_debug(P9_DEBUG_9P, "version error %d\n", err); + trace_9p_protocol_dump(c, &req->rc); + goto error; + } + + p9_debug(P9_DEBUG_9P, "<<< RVERSION msize %d %s\n", msize, version); + if (!strncmp(version, "9P2000.L", 8)) { + c->proto_version = p9_proto_2000L; + } else if (!strncmp(version, "9P2000.u", 8)) { + c->proto_version = p9_proto_2000u; + } else if (!strncmp(version, "9P2000", 6)) { + c->proto_version = p9_proto_legacy; + } else { + p9_debug(P9_DEBUG_ERROR, + "server returned an unknown version: %s\n", version); + err = -EREMOTEIO; + goto error; + } + + if (msize < 4096) { + p9_debug(P9_DEBUG_ERROR, + "server returned a msize < 4096: %d\n", msize); + err = -EREMOTEIO; + goto error; + } + if (msize < c->msize) + c->msize = msize; + +error: + kfree(version); + p9_req_put(c, req); + + return err; +} + +struct p9_client *p9_client_create(const char *dev_name, char *options) +{ + int err; + struct p9_client *clnt; + char *client_id; + + err = 0; + clnt = kmalloc(sizeof(*clnt), GFP_KERNEL); + if (!clnt) + return ERR_PTR(-ENOMEM); + + clnt->trans_mod = NULL; + clnt->trans = NULL; + clnt->fcall_cache = NULL; + + client_id = utsname()->nodename; + memcpy(clnt->name, client_id, strlen(client_id) + 1); + + spin_lock_init(&clnt->lock); + idr_init(&clnt->fids); + idr_init(&clnt->reqs); + + err = parse_opts(options, clnt); + if (err < 0) + goto free_client; + + if (!clnt->trans_mod) + clnt->trans_mod = v9fs_get_default_trans(); + + if (!clnt->trans_mod) { + err = -EPROTONOSUPPORT; + p9_debug(P9_DEBUG_ERROR, + "No transport defined or default transport\n"); + goto free_client; + } + + p9_debug(P9_DEBUG_MUX, "clnt %p trans %p msize %d protocol %d\n", + clnt, clnt->trans_mod, clnt->msize, clnt->proto_version); + + err = clnt->trans_mod->create(clnt, dev_name, options); + if (err) + goto put_trans; + + if (clnt->msize > clnt->trans_mod->maxsize) { + clnt->msize = clnt->trans_mod->maxsize; + pr_info("Limiting 'msize' to %d as this is the maximum " + "supported by transport %s\n", + clnt->msize, clnt->trans_mod->name + ); + } + + if (clnt->msize < 4096) { + p9_debug(P9_DEBUG_ERROR, + "Please specify a msize of at least 4k\n"); + err = -EINVAL; + goto close_trans; + } + + err = p9_client_version(clnt); + if (err) + goto close_trans; + + /* P9_HDRSZ + 4 is the smallest packet header we can have that is + * followed by data accessed from userspace by read + */ + clnt->fcall_cache = + kmem_cache_create_usercopy("9p-fcall-cache", clnt->msize, + 0, 0, P9_HDRSZ + 4, + clnt->msize - (P9_HDRSZ + 4), + NULL); + + return clnt; + +close_trans: + clnt->trans_mod->close(clnt); +put_trans: + v9fs_put_trans(clnt->trans_mod); +free_client: + kfree(clnt); + return ERR_PTR(err); +} +EXPORT_SYMBOL(p9_client_create); + +void p9_client_destroy(struct p9_client *clnt) +{ + struct p9_fid *fid; + int id; + + p9_debug(P9_DEBUG_MUX, "clnt %p\n", clnt); + + if (clnt->trans_mod) + clnt->trans_mod->close(clnt); + + v9fs_put_trans(clnt->trans_mod); + + idr_for_each_entry(&clnt->fids, fid, id) { + pr_info("Found fid %d not clunked\n", fid->fid); + p9_fid_destroy(fid); + } + + p9_tag_cleanup(clnt); + + kmem_cache_destroy(clnt->fcall_cache); + kfree(clnt); +} +EXPORT_SYMBOL(p9_client_destroy); + +void p9_client_disconnect(struct p9_client *clnt) +{ + p9_debug(P9_DEBUG_9P, "clnt %p\n", clnt); + clnt->status = Disconnected; +} +EXPORT_SYMBOL(p9_client_disconnect); + +void p9_client_begin_disconnect(struct p9_client *clnt) +{ + p9_debug(P9_DEBUG_9P, "clnt %p\n", clnt); + clnt->status = BeginDisconnect; +} +EXPORT_SYMBOL(p9_client_begin_disconnect); + +struct p9_fid *p9_client_attach(struct p9_client *clnt, struct p9_fid *afid, + const char *uname, kuid_t n_uname, + const char *aname) +{ + int err = 0; + struct p9_req_t *req; + struct p9_fid *fid; + struct p9_qid qid; + + p9_debug(P9_DEBUG_9P, ">>> TATTACH afid %d uname %s aname %s\n", + afid ? afid->fid : -1, uname, aname); + fid = p9_fid_create(clnt); + if (!fid) { + err = -ENOMEM; + goto error; + } + fid->uid = n_uname; + + req = p9_client_rpc(clnt, P9_TATTACH, "ddss?u", fid->fid, + afid ? afid->fid : P9_NOFID, uname, aname, n_uname); + if (IS_ERR(req)) { + err = PTR_ERR(req); + goto error; + } + + err = p9pdu_readf(&req->rc, clnt->proto_version, "Q", &qid); + if (err) { + trace_9p_protocol_dump(clnt, &req->rc); + p9_req_put(clnt, req); + goto error; + } + + p9_debug(P9_DEBUG_9P, "<<< RATTACH qid %x.%llx.%x\n", + qid.type, qid.path, qid.version); + + memmove(&fid->qid, &qid, sizeof(struct p9_qid)); + + p9_req_put(clnt, req); + return fid; + +error: + if (fid) + p9_fid_destroy(fid); + return ERR_PTR(err); +} +EXPORT_SYMBOL(p9_client_attach); + +struct p9_fid *p9_client_walk(struct p9_fid *oldfid, uint16_t nwname, + const unsigned char * const *wnames, int clone) +{ + int err; + struct p9_client *clnt; + struct p9_fid *fid; + struct p9_qid *wqids; + struct p9_req_t *req; + u16 nwqids, count; + + err = 0; + wqids = NULL; + clnt = oldfid->clnt; + if (clone) { + fid = p9_fid_create(clnt); + if (!fid) { + err = -ENOMEM; + goto error; + } + + fid->uid = oldfid->uid; + } else { + fid = oldfid; + } + + p9_debug(P9_DEBUG_9P, ">>> TWALK fids %d,%d nwname %ud wname[0] %s\n", + oldfid->fid, fid->fid, nwname, wnames ? wnames[0] : NULL); + req = p9_client_rpc(clnt, P9_TWALK, "ddT", oldfid->fid, fid->fid, + nwname, wnames); + if (IS_ERR(req)) { + err = PTR_ERR(req); + goto error; + } + + err = p9pdu_readf(&req->rc, clnt->proto_version, "R", &nwqids, &wqids); + if (err) { + trace_9p_protocol_dump(clnt, &req->rc); + p9_req_put(clnt, req); + goto clunk_fid; + } + p9_req_put(clnt, req); + + p9_debug(P9_DEBUG_9P, "<<< RWALK nwqid %d:\n", nwqids); + + if (nwqids != nwname) { + err = -ENOENT; + goto clunk_fid; + } + + for (count = 0; count < nwqids; count++) + p9_debug(P9_DEBUG_9P, "<<< [%d] %x.%llx.%x\n", + count, wqids[count].type, + wqids[count].path, + wqids[count].version); + + if (nwname) + memmove(&fid->qid, &wqids[nwqids - 1], sizeof(struct p9_qid)); + else + memmove(&fid->qid, &oldfid->qid, sizeof(struct p9_qid)); + + kfree(wqids); + return fid; + +clunk_fid: + kfree(wqids); + p9_fid_put(fid); + fid = NULL; + +error: + if (fid && fid != oldfid) + p9_fid_destroy(fid); + + return ERR_PTR(err); +} +EXPORT_SYMBOL(p9_client_walk); + +int p9_client_open(struct p9_fid *fid, int mode) +{ + int err; + struct p9_client *clnt; + struct p9_req_t *req; + struct p9_qid qid; + int iounit; + + clnt = fid->clnt; + p9_debug(P9_DEBUG_9P, ">>> %s fid %d mode %d\n", + p9_is_proto_dotl(clnt) ? "TLOPEN" : "TOPEN", fid->fid, mode); + err = 0; + + if (fid->mode != -1) + return -EINVAL; + + if (p9_is_proto_dotl(clnt)) + req = p9_client_rpc(clnt, P9_TLOPEN, "dd", fid->fid, mode); + else + req = p9_client_rpc(clnt, P9_TOPEN, "db", fid->fid, mode); + if (IS_ERR(req)) { + err = PTR_ERR(req); + goto error; + } + + err = p9pdu_readf(&req->rc, clnt->proto_version, "Qd", &qid, &iounit); + if (err) { + trace_9p_protocol_dump(clnt, &req->rc); + goto free_and_error; + } + + p9_debug(P9_DEBUG_9P, "<<< %s qid %x.%llx.%x iounit %x\n", + p9_is_proto_dotl(clnt) ? "RLOPEN" : "ROPEN", qid.type, + qid.path, qid.version, iounit); + + memmove(&fid->qid, &qid, sizeof(struct p9_qid)); + fid->mode = mode; + fid->iounit = iounit; + +free_and_error: + p9_req_put(clnt, req); +error: + return err; +} +EXPORT_SYMBOL(p9_client_open); + +int p9_client_create_dotl(struct p9_fid *ofid, const char *name, u32 flags, + u32 mode, kgid_t gid, struct p9_qid *qid) +{ + int err = 0; + struct p9_client *clnt; + struct p9_req_t *req; + int iounit; + + p9_debug(P9_DEBUG_9P, + ">>> TLCREATE fid %d name %s flags %d mode %d gid %d\n", + ofid->fid, name, flags, mode, + from_kgid(&init_user_ns, gid)); + clnt = ofid->clnt; + + if (ofid->mode != -1) + return -EINVAL; + + req = p9_client_rpc(clnt, P9_TLCREATE, "dsddg", ofid->fid, name, flags, + mode, gid); + if (IS_ERR(req)) { + err = PTR_ERR(req); + goto error; + } + + err = p9pdu_readf(&req->rc, clnt->proto_version, "Qd", qid, &iounit); + if (err) { + trace_9p_protocol_dump(clnt, &req->rc); + goto free_and_error; + } + + p9_debug(P9_DEBUG_9P, "<<< RLCREATE qid %x.%llx.%x iounit %x\n", + qid->type, qid->path, qid->version, iounit); + + memmove(&ofid->qid, qid, sizeof(struct p9_qid)); + ofid->mode = flags; + ofid->iounit = iounit; + +free_and_error: + p9_req_put(clnt, req); +error: + return err; +} +EXPORT_SYMBOL(p9_client_create_dotl); + +int p9_client_fcreate(struct p9_fid *fid, const char *name, u32 perm, int mode, + char *extension) +{ + int err; + struct p9_client *clnt; + struct p9_req_t *req; + struct p9_qid qid; + int iounit; + + p9_debug(P9_DEBUG_9P, ">>> TCREATE fid %d name %s perm %d mode %d\n", + fid->fid, name, perm, mode); + err = 0; + clnt = fid->clnt; + + if (fid->mode != -1) + return -EINVAL; + + req = p9_client_rpc(clnt, P9_TCREATE, "dsdb?s", fid->fid, name, perm, + mode, extension); + if (IS_ERR(req)) { + err = PTR_ERR(req); + goto error; + } + + err = p9pdu_readf(&req->rc, clnt->proto_version, "Qd", &qid, &iounit); + if (err) { + trace_9p_protocol_dump(clnt, &req->rc); + goto free_and_error; + } + + p9_debug(P9_DEBUG_9P, "<<< RCREATE qid %x.%llx.%x iounit %x\n", + qid.type, qid.path, qid.version, iounit); + + memmove(&fid->qid, &qid, sizeof(struct p9_qid)); + fid->mode = mode; + fid->iounit = iounit; + +free_and_error: + p9_req_put(clnt, req); +error: + return err; +} +EXPORT_SYMBOL(p9_client_fcreate); + +int p9_client_symlink(struct p9_fid *dfid, const char *name, + const char *symtgt, kgid_t gid, struct p9_qid *qid) +{ + int err = 0; + struct p9_client *clnt; + struct p9_req_t *req; + + p9_debug(P9_DEBUG_9P, ">>> TSYMLINK dfid %d name %s symtgt %s\n", + dfid->fid, name, symtgt); + clnt = dfid->clnt; + + req = p9_client_rpc(clnt, P9_TSYMLINK, "dssg", dfid->fid, name, symtgt, + gid); + if (IS_ERR(req)) { + err = PTR_ERR(req); + goto error; + } + + err = p9pdu_readf(&req->rc, clnt->proto_version, "Q", qid); + if (err) { + trace_9p_protocol_dump(clnt, &req->rc); + goto free_and_error; + } + + p9_debug(P9_DEBUG_9P, "<<< RSYMLINK qid %x.%llx.%x\n", + qid->type, qid->path, qid->version); + +free_and_error: + p9_req_put(clnt, req); +error: + return err; +} +EXPORT_SYMBOL(p9_client_symlink); + +int p9_client_link(struct p9_fid *dfid, struct p9_fid *oldfid, const char *newname) +{ + struct p9_client *clnt; + struct p9_req_t *req; + + p9_debug(P9_DEBUG_9P, ">>> TLINK dfid %d oldfid %d newname %s\n", + dfid->fid, oldfid->fid, newname); + clnt = dfid->clnt; + req = p9_client_rpc(clnt, P9_TLINK, "dds", dfid->fid, oldfid->fid, + newname); + if (IS_ERR(req)) + return PTR_ERR(req); + + p9_debug(P9_DEBUG_9P, "<<< RLINK\n"); + p9_req_put(clnt, req); + return 0; +} +EXPORT_SYMBOL(p9_client_link); + +int p9_client_fsync(struct p9_fid *fid, int datasync) +{ + int err; + struct p9_client *clnt; + struct p9_req_t *req; + + p9_debug(P9_DEBUG_9P, ">>> TFSYNC fid %d datasync:%d\n", + fid->fid, datasync); + err = 0; + clnt = fid->clnt; + + req = p9_client_rpc(clnt, P9_TFSYNC, "dd", fid->fid, datasync); + if (IS_ERR(req)) { + err = PTR_ERR(req); + goto error; + } + + p9_debug(P9_DEBUG_9P, "<<< RFSYNC fid %d\n", fid->fid); + + p9_req_put(clnt, req); + +error: + return err; +} +EXPORT_SYMBOL(p9_client_fsync); + +int p9_client_clunk(struct p9_fid *fid) +{ + int err; + struct p9_client *clnt; + struct p9_req_t *req; + int retries = 0; + +again: + p9_debug(P9_DEBUG_9P, ">>> TCLUNK fid %d (try %d)\n", + fid->fid, retries); + err = 0; + clnt = fid->clnt; + + req = p9_client_rpc(clnt, P9_TCLUNK, "d", fid->fid); + if (IS_ERR(req)) { + err = PTR_ERR(req); + goto error; + } + + p9_debug(P9_DEBUG_9P, "<<< RCLUNK fid %d\n", fid->fid); + + p9_req_put(clnt, req); +error: + /* Fid is not valid even after a failed clunk + * If interrupted, retry once then give up and + * leak fid until umount. + */ + if (err == -ERESTARTSYS) { + if (retries++ == 0) + goto again; + } else { + p9_fid_destroy(fid); + } + return err; +} +EXPORT_SYMBOL(p9_client_clunk); + +int p9_client_remove(struct p9_fid *fid) +{ + int err; + struct p9_client *clnt; + struct p9_req_t *req; + + p9_debug(P9_DEBUG_9P, ">>> TREMOVE fid %d\n", fid->fid); + err = 0; + clnt = fid->clnt; + + req = p9_client_rpc(clnt, P9_TREMOVE, "d", fid->fid); + if (IS_ERR(req)) { + err = PTR_ERR(req); + goto error; + } + + p9_debug(P9_DEBUG_9P, "<<< RREMOVE fid %d\n", fid->fid); + + p9_req_put(clnt, req); +error: + if (err == -ERESTARTSYS) + p9_fid_put(fid); + else + p9_fid_destroy(fid); + return err; +} +EXPORT_SYMBOL(p9_client_remove); + +int p9_client_unlinkat(struct p9_fid *dfid, const char *name, int flags) +{ + int err = 0; + struct p9_req_t *req; + struct p9_client *clnt; + + p9_debug(P9_DEBUG_9P, ">>> TUNLINKAT fid %d %s %d\n", + dfid->fid, name, flags); + + clnt = dfid->clnt; + req = p9_client_rpc(clnt, P9_TUNLINKAT, "dsd", dfid->fid, name, flags); + if (IS_ERR(req)) { + err = PTR_ERR(req); + goto error; + } + p9_debug(P9_DEBUG_9P, "<<< RUNLINKAT fid %d %s\n", dfid->fid, name); + + p9_req_put(clnt, req); +error: + return err; +} +EXPORT_SYMBOL(p9_client_unlinkat); + +int +p9_client_read(struct p9_fid *fid, u64 offset, struct iov_iter *to, int *err) +{ + int total = 0; + *err = 0; + + while (iov_iter_count(to)) { + int count; + + count = p9_client_read_once(fid, offset, to, err); + if (!count || *err) + break; + offset += count; + total += count; + } + return total; +} +EXPORT_SYMBOL(p9_client_read); + +int +p9_client_read_once(struct p9_fid *fid, u64 offset, struct iov_iter *to, + int *err) +{ + struct p9_client *clnt = fid->clnt; + struct p9_req_t *req; + int count = iov_iter_count(to); + int rsize, received, non_zc = 0; + char *dataptr; + + *err = 0; + p9_debug(P9_DEBUG_9P, ">>> TREAD fid %d offset %llu %zu\n", + fid->fid, offset, iov_iter_count(to)); + + rsize = fid->iounit; + if (!rsize || rsize > clnt->msize - P9_IOHDRSZ) + rsize = clnt->msize - P9_IOHDRSZ; + + if (count < rsize) + rsize = count; + + /* Don't bother zerocopy for small IO (< 1024) */ + if (clnt->trans_mod->zc_request && rsize > 1024) { + /* response header len is 11 + * PDU Header(7) + IO Size (4) + */ + req = p9_client_zc_rpc(clnt, P9_TREAD, to, NULL, rsize, + 0, 11, "dqd", fid->fid, + offset, rsize); + } else { + non_zc = 1; + req = p9_client_rpc(clnt, P9_TREAD, "dqd", fid->fid, offset, + rsize); + } + if (IS_ERR(req)) { + *err = PTR_ERR(req); + if (!non_zc) + iov_iter_revert(to, count - iov_iter_count(to)); + return 0; + } + + *err = p9pdu_readf(&req->rc, clnt->proto_version, + "D", &received, &dataptr); + if (*err) { + if (!non_zc) + iov_iter_revert(to, count - iov_iter_count(to)); + trace_9p_protocol_dump(clnt, &req->rc); + p9_req_put(clnt, req); + return 0; + } + if (rsize < received) { + pr_err("bogus RREAD count (%d > %d)\n", received, rsize); + received = rsize; + } + + p9_debug(P9_DEBUG_9P, "<<< RREAD count %d\n", count); + + if (non_zc) { + int n = copy_to_iter(dataptr, received, to); + + if (n != received) { + *err = -EFAULT; + p9_req_put(clnt, req); + return n; + } + } else { + iov_iter_revert(to, count - received - iov_iter_count(to)); + } + p9_req_put(clnt, req); + return received; +} +EXPORT_SYMBOL(p9_client_read_once); + +int +p9_client_write(struct p9_fid *fid, u64 offset, struct iov_iter *from, int *err) +{ + struct p9_client *clnt = fid->clnt; + struct p9_req_t *req; + int total = 0; + *err = 0; + + p9_debug(P9_DEBUG_9P, ">>> TWRITE fid %d offset %llu count %zd\n", + fid->fid, offset, iov_iter_count(from)); + + while (iov_iter_count(from)) { + int count = iov_iter_count(from); + int rsize = fid->iounit; + int written; + + if (!rsize || rsize > clnt->msize - P9_IOHDRSZ) + rsize = clnt->msize - P9_IOHDRSZ; + + if (count < rsize) + rsize = count; + + /* Don't bother zerocopy for small IO (< 1024) */ + if (clnt->trans_mod->zc_request && rsize > 1024) { + req = p9_client_zc_rpc(clnt, P9_TWRITE, NULL, from, 0, + rsize, P9_ZC_HDR_SZ, "dqd", + fid->fid, offset, rsize); + } else { + req = p9_client_rpc(clnt, P9_TWRITE, "dqV", fid->fid, + offset, rsize, from); + } + if (IS_ERR(req)) { + iov_iter_revert(from, count - iov_iter_count(from)); + *err = PTR_ERR(req); + break; + } + + *err = p9pdu_readf(&req->rc, clnt->proto_version, "d", &written); + if (*err) { + iov_iter_revert(from, count - iov_iter_count(from)); + trace_9p_protocol_dump(clnt, &req->rc); + p9_req_put(clnt, req); + break; + } + if (rsize < written) { + pr_err("bogus RWRITE count (%d > %d)\n", written, rsize); + written = rsize; + } + + p9_debug(P9_DEBUG_9P, "<<< RWRITE count %d\n", count); + + p9_req_put(clnt, req); + iov_iter_revert(from, count - written - iov_iter_count(from)); + total += written; + offset += written; + } + return total; +} +EXPORT_SYMBOL(p9_client_write); + +struct p9_wstat *p9_client_stat(struct p9_fid *fid) +{ + int err; + struct p9_client *clnt; + struct p9_wstat *ret; + struct p9_req_t *req; + u16 ignored; + + p9_debug(P9_DEBUG_9P, ">>> TSTAT fid %d\n", fid->fid); + + ret = kmalloc(sizeof(*ret), GFP_KERNEL); + if (!ret) + return ERR_PTR(-ENOMEM); + + err = 0; + clnt = fid->clnt; + + req = p9_client_rpc(clnt, P9_TSTAT, "d", fid->fid); + if (IS_ERR(req)) { + err = PTR_ERR(req); + goto error; + } + + err = p9pdu_readf(&req->rc, clnt->proto_version, "wS", &ignored, ret); + if (err) { + trace_9p_protocol_dump(clnt, &req->rc); + p9_req_put(clnt, req); + goto error; + } + + p9_debug(P9_DEBUG_9P, + "<<< RSTAT sz=%x type=%x dev=%x qid=%x.%llx.%x\n" + "<<< mode=%8.8x atime=%8.8x mtime=%8.8x length=%llx\n" + "<<< name=%s uid=%s gid=%s muid=%s extension=(%s)\n" + "<<< uid=%d gid=%d n_muid=%d\n", + ret->size, ret->type, ret->dev, ret->qid.type, ret->qid.path, + ret->qid.version, ret->mode, + ret->atime, ret->mtime, ret->length, + ret->name, ret->uid, ret->gid, ret->muid, ret->extension, + from_kuid(&init_user_ns, ret->n_uid), + from_kgid(&init_user_ns, ret->n_gid), + from_kuid(&init_user_ns, ret->n_muid)); + + p9_req_put(clnt, req); + return ret; + +error: + kfree(ret); + return ERR_PTR(err); +} +EXPORT_SYMBOL(p9_client_stat); + +struct p9_stat_dotl *p9_client_getattr_dotl(struct p9_fid *fid, + u64 request_mask) +{ + int err; + struct p9_client *clnt; + struct p9_stat_dotl *ret; + struct p9_req_t *req; + + p9_debug(P9_DEBUG_9P, ">>> TGETATTR fid %d, request_mask %lld\n", + fid->fid, request_mask); + + ret = kmalloc(sizeof(*ret), GFP_KERNEL); + if (!ret) + return ERR_PTR(-ENOMEM); + + err = 0; + clnt = fid->clnt; + + req = p9_client_rpc(clnt, P9_TGETATTR, "dq", fid->fid, request_mask); + if (IS_ERR(req)) { + err = PTR_ERR(req); + goto error; + } + + err = p9pdu_readf(&req->rc, clnt->proto_version, "A", ret); + if (err) { + trace_9p_protocol_dump(clnt, &req->rc); + p9_req_put(clnt, req); + goto error; + } + + p9_debug(P9_DEBUG_9P, "<<< RGETATTR st_result_mask=%lld\n" + "<<< qid=%x.%llx.%x\n" + "<<< st_mode=%8.8x st_nlink=%llu\n" + "<<< st_uid=%d st_gid=%d\n" + "<<< st_rdev=%llx st_size=%llx st_blksize=%llu st_blocks=%llu\n" + "<<< st_atime_sec=%lld st_atime_nsec=%lld\n" + "<<< st_mtime_sec=%lld st_mtime_nsec=%lld\n" + "<<< st_ctime_sec=%lld st_ctime_nsec=%lld\n" + "<<< st_btime_sec=%lld st_btime_nsec=%lld\n" + "<<< st_gen=%lld st_data_version=%lld\n", + ret->st_result_mask, + ret->qid.type, ret->qid.path, ret->qid.version, + ret->st_mode, ret->st_nlink, + from_kuid(&init_user_ns, ret->st_uid), + from_kgid(&init_user_ns, ret->st_gid), + ret->st_rdev, ret->st_size, ret->st_blksize, ret->st_blocks, + ret->st_atime_sec, ret->st_atime_nsec, + ret->st_mtime_sec, ret->st_mtime_nsec, + ret->st_ctime_sec, ret->st_ctime_nsec, + ret->st_btime_sec, ret->st_btime_nsec, + ret->st_gen, ret->st_data_version); + + p9_req_put(clnt, req); + return ret; + +error: + kfree(ret); + return ERR_PTR(err); +} +EXPORT_SYMBOL(p9_client_getattr_dotl); + +static int p9_client_statsize(struct p9_wstat *wst, int proto_version) +{ + int ret; + + /* NOTE: size shouldn't include its own length */ + /* size[2] type[2] dev[4] qid[13] */ + /* mode[4] atime[4] mtime[4] length[8]*/ + /* name[s] uid[s] gid[s] muid[s] */ + ret = 2 + 4 + 13 + 4 + 4 + 4 + 8 + 2 + 2 + 2 + 2; + + if (wst->name) + ret += strlen(wst->name); + if (wst->uid) + ret += strlen(wst->uid); + if (wst->gid) + ret += strlen(wst->gid); + if (wst->muid) + ret += strlen(wst->muid); + + if (proto_version == p9_proto_2000u || + proto_version == p9_proto_2000L) { + /* extension[s] n_uid[4] n_gid[4] n_muid[4] */ + ret += 2 + 4 + 4 + 4; + if (wst->extension) + ret += strlen(wst->extension); + } + + return ret; +} + +int p9_client_wstat(struct p9_fid *fid, struct p9_wstat *wst) +{ + int err; + struct p9_req_t *req; + struct p9_client *clnt; + + err = 0; + clnt = fid->clnt; + wst->size = p9_client_statsize(wst, clnt->proto_version); + p9_debug(P9_DEBUG_9P, ">>> TWSTAT fid %d\n", + fid->fid); + p9_debug(P9_DEBUG_9P, + " sz=%x type=%x dev=%x qid=%x.%llx.%x\n" + " mode=%8.8x atime=%8.8x mtime=%8.8x length=%llx\n" + " name=%s uid=%s gid=%s muid=%s extension=(%s)\n" + " uid=%d gid=%d n_muid=%d\n", + wst->size, wst->type, wst->dev, wst->qid.type, + wst->qid.path, wst->qid.version, + wst->mode, wst->atime, wst->mtime, wst->length, + wst->name, wst->uid, wst->gid, wst->muid, wst->extension, + from_kuid(&init_user_ns, wst->n_uid), + from_kgid(&init_user_ns, wst->n_gid), + from_kuid(&init_user_ns, wst->n_muid)); + + req = p9_client_rpc(clnt, P9_TWSTAT, "dwS", + fid->fid, wst->size + 2, wst); + if (IS_ERR(req)) { + err = PTR_ERR(req); + goto error; + } + + p9_debug(P9_DEBUG_9P, "<<< RWSTAT fid %d\n", fid->fid); + + p9_req_put(clnt, req); +error: + return err; +} +EXPORT_SYMBOL(p9_client_wstat); + +int p9_client_setattr(struct p9_fid *fid, struct p9_iattr_dotl *p9attr) +{ + int err; + struct p9_req_t *req; + struct p9_client *clnt; + + err = 0; + clnt = fid->clnt; + p9_debug(P9_DEBUG_9P, ">>> TSETATTR fid %d\n", fid->fid); + p9_debug(P9_DEBUG_9P, " valid=%x mode=%x uid=%d gid=%d size=%lld\n", + p9attr->valid, p9attr->mode, + from_kuid(&init_user_ns, p9attr->uid), + from_kgid(&init_user_ns, p9attr->gid), + p9attr->size); + p9_debug(P9_DEBUG_9P, " atime_sec=%lld atime_nsec=%lld\n", + p9attr->atime_sec, p9attr->atime_nsec); + p9_debug(P9_DEBUG_9P, " mtime_sec=%lld mtime_nsec=%lld\n", + p9attr->mtime_sec, p9attr->mtime_nsec); + + req = p9_client_rpc(clnt, P9_TSETATTR, "dI", fid->fid, p9attr); + + if (IS_ERR(req)) { + err = PTR_ERR(req); + goto error; + } + p9_debug(P9_DEBUG_9P, "<<< RSETATTR fid %d\n", fid->fid); + p9_req_put(clnt, req); +error: + return err; +} +EXPORT_SYMBOL(p9_client_setattr); + +int p9_client_statfs(struct p9_fid *fid, struct p9_rstatfs *sb) +{ + int err; + struct p9_req_t *req; + struct p9_client *clnt; + + err = 0; + clnt = fid->clnt; + + p9_debug(P9_DEBUG_9P, ">>> TSTATFS fid %d\n", fid->fid); + + req = p9_client_rpc(clnt, P9_TSTATFS, "d", fid->fid); + if (IS_ERR(req)) { + err = PTR_ERR(req); + goto error; + } + + err = p9pdu_readf(&req->rc, clnt->proto_version, "ddqqqqqqd", &sb->type, + &sb->bsize, &sb->blocks, &sb->bfree, &sb->bavail, + &sb->files, &sb->ffree, &sb->fsid, &sb->namelen); + if (err) { + trace_9p_protocol_dump(clnt, &req->rc); + p9_req_put(clnt, req); + goto error; + } + + p9_debug(P9_DEBUG_9P, + "<<< RSTATFS fid %d type 0x%x bsize %u blocks %llu bfree %llu bavail %llu files %llu ffree %llu fsid %llu namelen %u\n", + fid->fid, sb->type, sb->bsize, sb->blocks, sb->bfree, + sb->bavail, sb->files, sb->ffree, sb->fsid, sb->namelen); + + p9_req_put(clnt, req); +error: + return err; +} +EXPORT_SYMBOL(p9_client_statfs); + +int p9_client_rename(struct p9_fid *fid, + struct p9_fid *newdirfid, const char *name) +{ + int err; + struct p9_req_t *req; + struct p9_client *clnt; + + err = 0; + clnt = fid->clnt; + + p9_debug(P9_DEBUG_9P, ">>> TRENAME fid %d newdirfid %d name %s\n", + fid->fid, newdirfid->fid, name); + + req = p9_client_rpc(clnt, P9_TRENAME, "dds", fid->fid, + newdirfid->fid, name); + if (IS_ERR(req)) { + err = PTR_ERR(req); + goto error; + } + + p9_debug(P9_DEBUG_9P, "<<< RRENAME fid %d\n", fid->fid); + + p9_req_put(clnt, req); +error: + return err; +} +EXPORT_SYMBOL(p9_client_rename); + +int p9_client_renameat(struct p9_fid *olddirfid, const char *old_name, + struct p9_fid *newdirfid, const char *new_name) +{ + int err; + struct p9_req_t *req; + struct p9_client *clnt; + + err = 0; + clnt = olddirfid->clnt; + + p9_debug(P9_DEBUG_9P, + ">>> TRENAMEAT olddirfid %d old name %s newdirfid %d new name %s\n", + olddirfid->fid, old_name, newdirfid->fid, new_name); + + req = p9_client_rpc(clnt, P9_TRENAMEAT, "dsds", olddirfid->fid, + old_name, newdirfid->fid, new_name); + if (IS_ERR(req)) { + err = PTR_ERR(req); + goto error; + } + + p9_debug(P9_DEBUG_9P, "<<< RRENAMEAT newdirfid %d new name %s\n", + newdirfid->fid, new_name); + + p9_req_put(clnt, req); +error: + return err; +} +EXPORT_SYMBOL(p9_client_renameat); + +/* An xattrwalk without @attr_name gives the fid for the lisxattr namespace + */ +struct p9_fid *p9_client_xattrwalk(struct p9_fid *file_fid, + const char *attr_name, u64 *attr_size) +{ + int err; + struct p9_req_t *req; + struct p9_client *clnt; + struct p9_fid *attr_fid; + + err = 0; + clnt = file_fid->clnt; + attr_fid = p9_fid_create(clnt); + if (!attr_fid) { + err = -ENOMEM; + goto error; + } + p9_debug(P9_DEBUG_9P, + ">>> TXATTRWALK file_fid %d, attr_fid %d name '%s'\n", + file_fid->fid, attr_fid->fid, attr_name); + + req = p9_client_rpc(clnt, P9_TXATTRWALK, "dds", + file_fid->fid, attr_fid->fid, attr_name); + if (IS_ERR(req)) { + err = PTR_ERR(req); + goto error; + } + err = p9pdu_readf(&req->rc, clnt->proto_version, "q", attr_size); + if (err) { + trace_9p_protocol_dump(clnt, &req->rc); + p9_req_put(clnt, req); + goto clunk_fid; + } + p9_req_put(clnt, req); + p9_debug(P9_DEBUG_9P, "<<< RXATTRWALK fid %d size %llu\n", + attr_fid->fid, *attr_size); + return attr_fid; +clunk_fid: + p9_fid_put(attr_fid); + attr_fid = NULL; +error: + if (attr_fid && attr_fid != file_fid) + p9_fid_destroy(attr_fid); + + return ERR_PTR(err); +} +EXPORT_SYMBOL_GPL(p9_client_xattrwalk); + +int p9_client_xattrcreate(struct p9_fid *fid, const char *name, + u64 attr_size, int flags) +{ + int err; + struct p9_req_t *req; + struct p9_client *clnt; + + p9_debug(P9_DEBUG_9P, + ">>> TXATTRCREATE fid %d name %s size %llu flag %d\n", + fid->fid, name, attr_size, flags); + err = 0; + clnt = fid->clnt; + req = p9_client_rpc(clnt, P9_TXATTRCREATE, "dsqd", + fid->fid, name, attr_size, flags); + if (IS_ERR(req)) { + err = PTR_ERR(req); + goto error; + } + p9_debug(P9_DEBUG_9P, "<<< RXATTRCREATE fid %d\n", fid->fid); + p9_req_put(clnt, req); +error: + return err; +} +EXPORT_SYMBOL_GPL(p9_client_xattrcreate); + +int p9_client_readdir(struct p9_fid *fid, char *data, u32 count, u64 offset) +{ + int err, rsize, non_zc = 0; + struct p9_client *clnt; + struct p9_req_t *req; + char *dataptr; + struct kvec kv = {.iov_base = data, .iov_len = count}; + struct iov_iter to; + + iov_iter_kvec(&to, ITER_DEST, &kv, 1, count); + + p9_debug(P9_DEBUG_9P, ">>> TREADDIR fid %d offset %llu count %d\n", + fid->fid, offset, count); + + err = 0; + clnt = fid->clnt; + + rsize = fid->iounit; + if (!rsize || rsize > clnt->msize - P9_READDIRHDRSZ) + rsize = clnt->msize - P9_READDIRHDRSZ; + + if (count < rsize) + rsize = count; + + /* Don't bother zerocopy for small IO (< 1024) */ + if (clnt->trans_mod->zc_request && rsize > 1024) { + /* response header len is 11 + * PDU Header(7) + IO Size (4) + */ + req = p9_client_zc_rpc(clnt, P9_TREADDIR, &to, NULL, rsize, 0, + 11, "dqd", fid->fid, offset, rsize); + } else { + non_zc = 1; + req = p9_client_rpc(clnt, P9_TREADDIR, "dqd", fid->fid, + offset, rsize); + } + if (IS_ERR(req)) { + err = PTR_ERR(req); + goto error; + } + + err = p9pdu_readf(&req->rc, clnt->proto_version, "D", &count, &dataptr); + if (err) { + trace_9p_protocol_dump(clnt, &req->rc); + goto free_and_error; + } + if (rsize < count) { + pr_err("bogus RREADDIR count (%d > %d)\n", count, rsize); + count = rsize; + } + + p9_debug(P9_DEBUG_9P, "<<< RREADDIR count %d\n", count); + + if (non_zc) + memmove(data, dataptr, count); + + p9_req_put(clnt, req); + return count; + +free_and_error: + p9_req_put(clnt, req); +error: + return err; +} +EXPORT_SYMBOL(p9_client_readdir); + +int p9_client_mknod_dotl(struct p9_fid *fid, const char *name, int mode, + dev_t rdev, kgid_t gid, struct p9_qid *qid) +{ + int err; + struct p9_client *clnt; + struct p9_req_t *req; + + err = 0; + clnt = fid->clnt; + p9_debug(P9_DEBUG_9P, + ">>> TMKNOD fid %d name %s mode %d major %d minor %d\n", + fid->fid, name, mode, MAJOR(rdev), MINOR(rdev)); + req = p9_client_rpc(clnt, P9_TMKNOD, "dsdddg", fid->fid, name, mode, + MAJOR(rdev), MINOR(rdev), gid); + if (IS_ERR(req)) + return PTR_ERR(req); + + err = p9pdu_readf(&req->rc, clnt->proto_version, "Q", qid); + if (err) { + trace_9p_protocol_dump(clnt, &req->rc); + goto error; + } + p9_debug(P9_DEBUG_9P, "<<< RMKNOD qid %x.%llx.%x\n", + qid->type, qid->path, qid->version); + +error: + p9_req_put(clnt, req); + return err; +} +EXPORT_SYMBOL(p9_client_mknod_dotl); + +int p9_client_mkdir_dotl(struct p9_fid *fid, const char *name, int mode, + kgid_t gid, struct p9_qid *qid) +{ + int err; + struct p9_client *clnt; + struct p9_req_t *req; + + err = 0; + clnt = fid->clnt; + p9_debug(P9_DEBUG_9P, ">>> TMKDIR fid %d name %s mode %d gid %d\n", + fid->fid, name, mode, from_kgid(&init_user_ns, gid)); + req = p9_client_rpc(clnt, P9_TMKDIR, "dsdg", + fid->fid, name, mode, gid); + if (IS_ERR(req)) + return PTR_ERR(req); + + err = p9pdu_readf(&req->rc, clnt->proto_version, "Q", qid); + if (err) { + trace_9p_protocol_dump(clnt, &req->rc); + goto error; + } + p9_debug(P9_DEBUG_9P, "<<< RMKDIR qid %x.%llx.%x\n", qid->type, + qid->path, qid->version); + +error: + p9_req_put(clnt, req); + return err; +} +EXPORT_SYMBOL(p9_client_mkdir_dotl); + +int p9_client_lock_dotl(struct p9_fid *fid, struct p9_flock *flock, u8 *status) +{ + int err; + struct p9_client *clnt; + struct p9_req_t *req; + + err = 0; + clnt = fid->clnt; + p9_debug(P9_DEBUG_9P, + ">>> TLOCK fid %d type %i flags %d start %lld length %lld proc_id %d client_id %s\n", + fid->fid, flock->type, flock->flags, flock->start, + flock->length, flock->proc_id, flock->client_id); + + req = p9_client_rpc(clnt, P9_TLOCK, "dbdqqds", fid->fid, flock->type, + flock->flags, flock->start, flock->length, + flock->proc_id, flock->client_id); + + if (IS_ERR(req)) + return PTR_ERR(req); + + err = p9pdu_readf(&req->rc, clnt->proto_version, "b", status); + if (err) { + trace_9p_protocol_dump(clnt, &req->rc); + goto error; + } + p9_debug(P9_DEBUG_9P, "<<< RLOCK status %i\n", *status); +error: + p9_req_put(clnt, req); + return err; +} +EXPORT_SYMBOL(p9_client_lock_dotl); + +int p9_client_getlock_dotl(struct p9_fid *fid, struct p9_getlock *glock) +{ + int err; + struct p9_client *clnt; + struct p9_req_t *req; + + err = 0; + clnt = fid->clnt; + p9_debug(P9_DEBUG_9P, + ">>> TGETLOCK fid %d, type %i start %lld length %lld proc_id %d client_id %s\n", + fid->fid, glock->type, glock->start, glock->length, + glock->proc_id, glock->client_id); + + req = p9_client_rpc(clnt, P9_TGETLOCK, "dbqqds", fid->fid, + glock->type, glock->start, glock->length, + glock->proc_id, glock->client_id); + + if (IS_ERR(req)) + return PTR_ERR(req); + + err = p9pdu_readf(&req->rc, clnt->proto_version, "bqqds", &glock->type, + &glock->start, &glock->length, &glock->proc_id, + &glock->client_id); + if (err) { + trace_9p_protocol_dump(clnt, &req->rc); + goto error; + } + p9_debug(P9_DEBUG_9P, + "<<< RGETLOCK type %i start %lld length %lld proc_id %d client_id %s\n", + glock->type, glock->start, glock->length, + glock->proc_id, glock->client_id); +error: + p9_req_put(clnt, req); + return err; +} +EXPORT_SYMBOL(p9_client_getlock_dotl); + +int p9_client_readlink(struct p9_fid *fid, char **target) +{ + int err; + struct p9_client *clnt; + struct p9_req_t *req; + + err = 0; + clnt = fid->clnt; + p9_debug(P9_DEBUG_9P, ">>> TREADLINK fid %d\n", fid->fid); + + req = p9_client_rpc(clnt, P9_TREADLINK, "d", fid->fid); + if (IS_ERR(req)) + return PTR_ERR(req); + + err = p9pdu_readf(&req->rc, clnt->proto_version, "s", target); + if (err) { + trace_9p_protocol_dump(clnt, &req->rc); + goto error; + } + p9_debug(P9_DEBUG_9P, "<<< RREADLINK target %s\n", *target); +error: + p9_req_put(clnt, req); + return err; +} +EXPORT_SYMBOL(p9_client_readlink); + +int __init p9_client_init(void) +{ + p9_req_cache = KMEM_CACHE(p9_req_t, SLAB_TYPESAFE_BY_RCU); + return p9_req_cache ? 0 : -ENOMEM; +} + +void __exit p9_client_exit(void) +{ + kmem_cache_destroy(p9_req_cache); +} |