From c3e9f888263bb4df11cbd623ceced02081cb2f9f Mon Sep 17 00:00:00 2001 From: David Howells Date: Wed, 29 Apr 2020 17:26:41 +0100 Subject: afs: Implement client support for the YFSVL.GetCellName RPC op Implement client support for the YFSVL.GetCellName RPC operation by which YFS permits the canonical cell name to be queried from a VL server. Signed-off-by: David Howells --- fs/afs/vlclient.c | 111 ++++++++++++++++++++++++++++++++++++++++++++++++++++++ 1 file changed, 111 insertions(+) (limited to 'fs/afs/vlclient.c') diff --git a/fs/afs/vlclient.c b/fs/afs/vlclient.c index d0c85623ce8f..fd82850cd424 100644 --- a/fs/afs/vlclient.c +++ b/fs/afs/vlclient.c @@ -645,3 +645,114 @@ struct afs_addr_list *afs_yfsvl_get_endpoints(struct afs_vl_cursor *vc, afs_make_call(&vc->ac, call, GFP_KERNEL); return (struct afs_addr_list *)afs_wait_for_call_to_complete(call, &vc->ac); } + +/* + * Deliver reply data to a YFSVL.GetCellName operation. + */ +static int afs_deliver_yfsvl_get_cell_name(struct afs_call *call) +{ + char *cell_name; + u32 namesz, paddedsz; + int ret; + + _enter("{%u,%zu/%u}", + call->unmarshall, iov_iter_count(call->iter), call->count); + + switch (call->unmarshall) { + case 0: + afs_extract_to_tmp(call); + call->unmarshall++; + + /* Fall through - and extract the cell name length */ + case 1: + ret = afs_extract_data(call, true); + if (ret < 0) + return ret; + + namesz = ntohl(call->tmp); + if (namesz > AFS_MAXCELLNAME) + return afs_protocol_error(call, afs_eproto_cellname_len); + paddedsz = (namesz + 3) & ~3; + call->count = namesz; + call->count2 = paddedsz - namesz; + + cell_name = kmalloc(namesz + 1, GFP_KERNEL); + if (!cell_name) + return -ENOMEM; + cell_name[namesz] = 0; + call->ret_str = cell_name; + + afs_extract_begin(call, cell_name, namesz); + call->unmarshall++; + + /* Fall through - and extract cell name */ + case 2: + ret = afs_extract_data(call, true); + if (ret < 0) + return ret; + + afs_extract_discard(call, call->count2); + call->unmarshall++; + + /* Fall through - and extract padding */ + case 3: + ret = afs_extract_data(call, false); + if (ret < 0) + return ret; + + call->unmarshall++; + break; + } + + _leave(" = 0 [done]"); + return 0; +} + +static void afs_destroy_yfsvl_get_cell_name(struct afs_call *call) +{ + kfree(call->ret_str); + afs_flat_call_destructor(call); +} + +/* + * VL.GetCapabilities operation type + */ +static const struct afs_call_type afs_YFSVLGetCellName = { + .name = "YFSVL.GetCellName", + .op = afs_YFSVL_GetCellName, + .deliver = afs_deliver_yfsvl_get_cell_name, + .destructor = afs_destroy_yfsvl_get_cell_name, +}; + +/* + * Probe a volume server for the capabilities that it supports. This can + * return up to 196 words. + * + * We use this to probe for service upgrade to determine what the server at the + * other end supports. + */ +char *afs_yfsvl_get_cell_name(struct afs_vl_cursor *vc) +{ + struct afs_call *call; + struct afs_net *net = vc->cell->net; + __be32 *bp; + + _enter(""); + + call = afs_alloc_flat_call(net, &afs_YFSVLGetCellName, 1 * 4, 0); + if (!call) + return ERR_PTR(-ENOMEM); + + call->key = vc->key; + call->ret_str = NULL; + call->max_lifespan = AFS_VL_MAX_LIFESPAN; + + /* marshall the parameters */ + bp = call->request; + *bp++ = htonl(YVLGETCELLNAME); + + /* Can't take a ref on server */ + trace_afs_make_vl_call(call); + afs_make_call(&vc->ac, call, GFP_KERNEL); + return (char *)afs_wait_for_call_to_complete(call, &vc->ac); +} -- cgit v1.2.3