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authorDaniel Baumann <daniel.baumann@progress-linux.org>2024-04-11 08:27:49 +0000
committerDaniel Baumann <daniel.baumann@progress-linux.org>2024-04-11 08:27:49 +0000
commitace9429bb58fd418f0c81d4c2835699bddf6bde6 (patch)
treeb2d64bc10158fdd5497876388cd68142ca374ed3 /fs/afs/vlclient.c
parentInitial commit. (diff)
downloadlinux-ace9429bb58fd418f0c81d4c2835699bddf6bde6.tar.xz
linux-ace9429bb58fd418f0c81d4c2835699bddf6bde6.zip
Adding upstream version 6.6.15.upstream/6.6.15
Signed-off-by: Daniel Baumann <daniel.baumann@progress-linux.org>
Diffstat (limited to 'fs/afs/vlclient.c')
-rw-r--r--fs/afs/vlclient.c759
1 files changed, 759 insertions, 0 deletions
diff --git a/fs/afs/vlclient.c b/fs/afs/vlclient.c
new file mode 100644
index 0000000000..00fca3c66b
--- /dev/null
+++ b/fs/afs/vlclient.c
@@ -0,0 +1,759 @@
+// SPDX-License-Identifier: GPL-2.0-or-later
+/* AFS Volume Location Service client
+ *
+ * Copyright (C) 2002 Red Hat, Inc. All Rights Reserved.
+ * Written by David Howells (dhowells@redhat.com)
+ */
+
+#include <linux/gfp.h>
+#include <linux/init.h>
+#include <linux/sched.h>
+#include "afs_fs.h"
+#include "internal.h"
+
+/*
+ * Deliver reply data to a VL.GetEntryByNameU call.
+ */
+static int afs_deliver_vl_get_entry_by_name_u(struct afs_call *call)
+{
+ struct afs_uvldbentry__xdr *uvldb;
+ struct afs_vldb_entry *entry;
+ bool new_only = false;
+ u32 tmp, nr_servers, vlflags;
+ int i, ret;
+
+ _enter("");
+
+ ret = afs_transfer_reply(call);
+ if (ret < 0)
+ return ret;
+
+ /* unmarshall the reply once we've received all of it */
+ uvldb = call->buffer;
+ entry = call->ret_vldb;
+
+ nr_servers = ntohl(uvldb->nServers);
+ if (nr_servers > AFS_NMAXNSERVERS)
+ nr_servers = AFS_NMAXNSERVERS;
+
+ for (i = 0; i < ARRAY_SIZE(uvldb->name) - 1; i++)
+ entry->name[i] = (u8)ntohl(uvldb->name[i]);
+ entry->name[i] = 0;
+ entry->name_len = strlen(entry->name);
+
+ /* If there is a new replication site that we can use, ignore all the
+ * sites that aren't marked as new.
+ */
+ for (i = 0; i < nr_servers; i++) {
+ tmp = ntohl(uvldb->serverFlags[i]);
+ if (!(tmp & AFS_VLSF_DONTUSE) &&
+ (tmp & AFS_VLSF_NEWREPSITE))
+ new_only = true;
+ }
+
+ vlflags = ntohl(uvldb->flags);
+ for (i = 0; i < nr_servers; i++) {
+ struct afs_uuid__xdr *xdr;
+ struct afs_uuid *uuid;
+ int j;
+ int n = entry->nr_servers;
+
+ tmp = ntohl(uvldb->serverFlags[i]);
+ if (tmp & AFS_VLSF_DONTUSE ||
+ (new_only && !(tmp & AFS_VLSF_NEWREPSITE)))
+ continue;
+ if (tmp & AFS_VLSF_RWVOL) {
+ entry->fs_mask[n] |= AFS_VOL_VTM_RW;
+ if (vlflags & AFS_VLF_BACKEXISTS)
+ entry->fs_mask[n] |= AFS_VOL_VTM_BAK;
+ }
+ if (tmp & AFS_VLSF_ROVOL)
+ entry->fs_mask[n] |= AFS_VOL_VTM_RO;
+ if (!entry->fs_mask[n])
+ continue;
+
+ xdr = &uvldb->serverNumber[i];
+ uuid = (struct afs_uuid *)&entry->fs_server[n];
+ uuid->time_low = xdr->time_low;
+ uuid->time_mid = htons(ntohl(xdr->time_mid));
+ uuid->time_hi_and_version = htons(ntohl(xdr->time_hi_and_version));
+ uuid->clock_seq_hi_and_reserved = (u8)ntohl(xdr->clock_seq_hi_and_reserved);
+ uuid->clock_seq_low = (u8)ntohl(xdr->clock_seq_low);
+ for (j = 0; j < 6; j++)
+ uuid->node[j] = (u8)ntohl(xdr->node[j]);
+
+ entry->addr_version[n] = ntohl(uvldb->serverUnique[i]);
+ entry->nr_servers++;
+ }
+
+ for (i = 0; i < AFS_MAXTYPES; i++)
+ entry->vid[i] = ntohl(uvldb->volumeId[i]);
+
+ if (vlflags & AFS_VLF_RWEXISTS)
+ __set_bit(AFS_VLDB_HAS_RW, &entry->flags);
+ if (vlflags & AFS_VLF_ROEXISTS)
+ __set_bit(AFS_VLDB_HAS_RO, &entry->flags);
+ if (vlflags & AFS_VLF_BACKEXISTS)
+ __set_bit(AFS_VLDB_HAS_BAK, &entry->flags);
+
+ if (!(vlflags & (AFS_VLF_RWEXISTS | AFS_VLF_ROEXISTS | AFS_VLF_BACKEXISTS))) {
+ entry->error = -ENOMEDIUM;
+ __set_bit(AFS_VLDB_QUERY_ERROR, &entry->flags);
+ }
+
+ __set_bit(AFS_VLDB_QUERY_VALID, &entry->flags);
+ _leave(" = 0 [done]");
+ return 0;
+}
+
+static void afs_destroy_vl_get_entry_by_name_u(struct afs_call *call)
+{
+ kfree(call->ret_vldb);
+ afs_flat_call_destructor(call);
+}
+
+/*
+ * VL.GetEntryByNameU operation type.
+ */
+static const struct afs_call_type afs_RXVLGetEntryByNameU = {
+ .name = "VL.GetEntryByNameU",
+ .op = afs_VL_GetEntryByNameU,
+ .deliver = afs_deliver_vl_get_entry_by_name_u,
+ .destructor = afs_destroy_vl_get_entry_by_name_u,
+};
+
+/*
+ * Dispatch a get volume entry by name or ID operation (uuid variant). If the
+ * volname is a decimal number then it's a volume ID not a volume name.
+ */
+struct afs_vldb_entry *afs_vl_get_entry_by_name_u(struct afs_vl_cursor *vc,
+ const char *volname,
+ int volnamesz)
+{
+ struct afs_vldb_entry *entry;
+ struct afs_call *call;
+ struct afs_net *net = vc->cell->net;
+ size_t reqsz, padsz;
+ __be32 *bp;
+
+ _enter("");
+
+ padsz = (4 - (volnamesz & 3)) & 3;
+ reqsz = 8 + volnamesz + padsz;
+
+ entry = kzalloc(sizeof(struct afs_vldb_entry), GFP_KERNEL);
+ if (!entry)
+ return ERR_PTR(-ENOMEM);
+
+ call = afs_alloc_flat_call(net, &afs_RXVLGetEntryByNameU, reqsz,
+ sizeof(struct afs_uvldbentry__xdr));
+ if (!call) {
+ kfree(entry);
+ return ERR_PTR(-ENOMEM);
+ }
+
+ call->key = vc->key;
+ call->ret_vldb = entry;
+ call->max_lifespan = AFS_VL_MAX_LIFESPAN;
+
+ /* Marshall the parameters */
+ bp = call->request;
+ *bp++ = htonl(VLGETENTRYBYNAMEU);
+ *bp++ = htonl(volnamesz);
+ memcpy(bp, volname, volnamesz);
+ if (padsz > 0)
+ memset((void *)bp + volnamesz, 0, padsz);
+
+ trace_afs_make_vl_call(call);
+ afs_make_call(&vc->ac, call, GFP_KERNEL);
+ return (struct afs_vldb_entry *)afs_wait_for_call_to_complete(call, &vc->ac);
+}
+
+/*
+ * Deliver reply data to a VL.GetAddrsU call.
+ *
+ * GetAddrsU(IN ListAddrByAttributes *inaddr,
+ * OUT afsUUID *uuidp1,
+ * OUT uint32_t *uniquifier,
+ * OUT uint32_t *nentries,
+ * OUT bulkaddrs *blkaddrs);
+ */
+static int afs_deliver_vl_get_addrs_u(struct afs_call *call)
+{
+ struct afs_addr_list *alist;
+ __be32 *bp;
+ u32 uniquifier, nentries, count;
+ int i, ret;
+
+ _enter("{%u,%zu/%u}",
+ call->unmarshall, iov_iter_count(call->iter), call->count);
+
+ switch (call->unmarshall) {
+ case 0:
+ afs_extract_to_buf(call,
+ sizeof(struct afs_uuid__xdr) + 3 * sizeof(__be32));
+ call->unmarshall++;
+
+ /* Extract the returned uuid, uniquifier, nentries and
+ * blkaddrs size */
+ fallthrough;
+ case 1:
+ ret = afs_extract_data(call, true);
+ if (ret < 0)
+ return ret;
+
+ bp = call->buffer + sizeof(struct afs_uuid__xdr);
+ uniquifier = ntohl(*bp++);
+ nentries = ntohl(*bp++);
+ count = ntohl(*bp);
+
+ nentries = min(nentries, count);
+ alist = afs_alloc_addrlist(nentries, FS_SERVICE, AFS_FS_PORT);
+ if (!alist)
+ return -ENOMEM;
+ alist->version = uniquifier;
+ call->ret_alist = alist;
+ call->count = count;
+ call->count2 = nentries;
+ call->unmarshall++;
+
+ more_entries:
+ count = min(call->count, 4U);
+ afs_extract_to_buf(call, count * sizeof(__be32));
+
+ fallthrough; /* and extract entries */
+ case 2:
+ ret = afs_extract_data(call, call->count > 4);
+ if (ret < 0)
+ return ret;
+
+ alist = call->ret_alist;
+ bp = call->buffer;
+ count = min(call->count, 4U);
+ for (i = 0; i < count; i++)
+ if (alist->nr_addrs < call->count2)
+ afs_merge_fs_addr4(alist, *bp++, AFS_FS_PORT);
+
+ call->count -= count;
+ if (call->count > 0)
+ goto more_entries;
+ call->unmarshall++;
+ break;
+ }
+
+ _leave(" = 0 [done]");
+ return 0;
+}
+
+static void afs_vl_get_addrs_u_destructor(struct afs_call *call)
+{
+ afs_put_addrlist(call->ret_alist);
+ return afs_flat_call_destructor(call);
+}
+
+/*
+ * VL.GetAddrsU operation type.
+ */
+static const struct afs_call_type afs_RXVLGetAddrsU = {
+ .name = "VL.GetAddrsU",
+ .op = afs_VL_GetAddrsU,
+ .deliver = afs_deliver_vl_get_addrs_u,
+ .destructor = afs_vl_get_addrs_u_destructor,
+};
+
+/*
+ * Dispatch an operation to get the addresses for a server, where the server is
+ * nominated by UUID.
+ */
+struct afs_addr_list *afs_vl_get_addrs_u(struct afs_vl_cursor *vc,
+ const uuid_t *uuid)
+{
+ struct afs_ListAddrByAttributes__xdr *r;
+ const struct afs_uuid *u = (const struct afs_uuid *)uuid;
+ struct afs_call *call;
+ struct afs_net *net = vc->cell->net;
+ __be32 *bp;
+ int i;
+
+ _enter("");
+
+ call = afs_alloc_flat_call(net, &afs_RXVLGetAddrsU,
+ sizeof(__be32) + sizeof(struct afs_ListAddrByAttributes__xdr),
+ sizeof(struct afs_uuid__xdr) + 3 * sizeof(__be32));
+ if (!call)
+ return ERR_PTR(-ENOMEM);
+
+ call->key = vc->key;
+ call->ret_alist = NULL;
+ call->max_lifespan = AFS_VL_MAX_LIFESPAN;
+
+ /* Marshall the parameters */
+ bp = call->request;
+ *bp++ = htonl(VLGETADDRSU);
+ r = (struct afs_ListAddrByAttributes__xdr *)bp;
+ r->Mask = htonl(AFS_VLADDR_UUID);
+ r->ipaddr = 0;
+ r->index = 0;
+ r->spare = 0;
+ r->uuid.time_low = u->time_low;
+ r->uuid.time_mid = htonl(ntohs(u->time_mid));
+ r->uuid.time_hi_and_version = htonl(ntohs(u->time_hi_and_version));
+ r->uuid.clock_seq_hi_and_reserved = htonl(u->clock_seq_hi_and_reserved);
+ r->uuid.clock_seq_low = htonl(u->clock_seq_low);
+ for (i = 0; i < 6; i++)
+ r->uuid.node[i] = htonl(u->node[i]);
+
+ trace_afs_make_vl_call(call);
+ 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 an VL.GetCapabilities operation.
+ */
+static int afs_deliver_vl_get_capabilities(struct afs_call *call)
+{
+ u32 count;
+ 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++;
+
+ fallthrough; /* and extract the capabilities word count */
+ case 1:
+ ret = afs_extract_data(call, true);
+ if (ret < 0)
+ return ret;
+
+ count = ntohl(call->tmp);
+ call->count = count;
+ call->count2 = count;
+
+ call->unmarshall++;
+ afs_extract_discard(call, count * sizeof(__be32));
+
+ fallthrough; /* and extract capabilities words */
+ case 2:
+ ret = afs_extract_data(call, false);
+ if (ret < 0)
+ return ret;
+
+ /* TODO: Examine capabilities */
+
+ call->unmarshall++;
+ break;
+ }
+
+ _leave(" = 0 [done]");
+ return 0;
+}
+
+static void afs_destroy_vl_get_capabilities(struct afs_call *call)
+{
+ afs_put_vlserver(call->net, call->vlserver);
+ afs_flat_call_destructor(call);
+}
+
+/*
+ * VL.GetCapabilities operation type
+ */
+static const struct afs_call_type afs_RXVLGetCapabilities = {
+ .name = "VL.GetCapabilities",
+ .op = afs_VL_GetCapabilities,
+ .deliver = afs_deliver_vl_get_capabilities,
+ .done = afs_vlserver_probe_result,
+ .destructor = afs_destroy_vl_get_capabilities,
+};
+
+/*
+ * 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.
+ */
+struct afs_call *afs_vl_get_capabilities(struct afs_net *net,
+ struct afs_addr_cursor *ac,
+ struct key *key,
+ struct afs_vlserver *server,
+ unsigned int server_index)
+{
+ struct afs_call *call;
+ __be32 *bp;
+
+ _enter("");
+
+ call = afs_alloc_flat_call(net, &afs_RXVLGetCapabilities, 1 * 4, 16 * 4);
+ if (!call)
+ return ERR_PTR(-ENOMEM);
+
+ call->key = key;
+ call->vlserver = afs_get_vlserver(server);
+ call->server_index = server_index;
+ call->upgrade = true;
+ call->async = true;
+ call->max_lifespan = AFS_PROBE_MAX_LIFESPAN;
+
+ /* marshall the parameters */
+ bp = call->request;
+ *bp++ = htonl(VLGETCAPABILITIES);
+
+ /* Can't take a ref on server */
+ trace_afs_make_vl_call(call);
+ afs_make_call(ac, call, GFP_KERNEL);
+ return call;
+}
+
+/*
+ * Deliver reply data to a YFSVL.GetEndpoints call.
+ *
+ * GetEndpoints(IN yfsServerAttributes *attr,
+ * OUT opr_uuid *uuid,
+ * OUT afs_int32 *uniquifier,
+ * OUT endpoints *fsEndpoints,
+ * OUT endpoints *volEndpoints)
+ */
+static int afs_deliver_yfsvl_get_endpoints(struct afs_call *call)
+{
+ struct afs_addr_list *alist;
+ __be32 *bp;
+ u32 uniquifier, size;
+ int ret;
+
+ _enter("{%u,%zu,%u}",
+ call->unmarshall, iov_iter_count(call->iter), call->count2);
+
+ switch (call->unmarshall) {
+ case 0:
+ afs_extract_to_buf(call, sizeof(uuid_t) + 3 * sizeof(__be32));
+ call->unmarshall = 1;
+
+ /* Extract the returned uuid, uniquifier, fsEndpoints count and
+ * either the first fsEndpoint type or the volEndpoints
+ * count if there are no fsEndpoints. */
+ fallthrough;
+ case 1:
+ ret = afs_extract_data(call, true);
+ if (ret < 0)
+ return ret;
+
+ bp = call->buffer + sizeof(uuid_t);
+ uniquifier = ntohl(*bp++);
+ call->count = ntohl(*bp++);
+ call->count2 = ntohl(*bp); /* Type or next count */
+
+ if (call->count > YFS_MAXENDPOINTS)
+ return afs_protocol_error(call, afs_eproto_yvl_fsendpt_num);
+
+ alist = afs_alloc_addrlist(call->count, FS_SERVICE, AFS_FS_PORT);
+ if (!alist)
+ return -ENOMEM;
+ alist->version = uniquifier;
+ call->ret_alist = alist;
+
+ if (call->count == 0)
+ goto extract_volendpoints;
+
+ next_fsendpoint:
+ switch (call->count2) {
+ case YFS_ENDPOINT_IPV4:
+ size = sizeof(__be32) * (1 + 1 + 1);
+ break;
+ case YFS_ENDPOINT_IPV6:
+ size = sizeof(__be32) * (1 + 4 + 1);
+ break;
+ default:
+ return afs_protocol_error(call, afs_eproto_yvl_fsendpt_type);
+ }
+
+ size += sizeof(__be32);
+ afs_extract_to_buf(call, size);
+ call->unmarshall = 2;
+
+ fallthrough; /* and extract fsEndpoints[] entries */
+ case 2:
+ ret = afs_extract_data(call, true);
+ if (ret < 0)
+ return ret;
+
+ alist = call->ret_alist;
+ bp = call->buffer;
+ switch (call->count2) {
+ case YFS_ENDPOINT_IPV4:
+ if (ntohl(bp[0]) != sizeof(__be32) * 2)
+ return afs_protocol_error(
+ call, afs_eproto_yvl_fsendpt4_len);
+ afs_merge_fs_addr4(alist, bp[1], ntohl(bp[2]));
+ bp += 3;
+ break;
+ case YFS_ENDPOINT_IPV6:
+ if (ntohl(bp[0]) != sizeof(__be32) * 5)
+ return afs_protocol_error(
+ call, afs_eproto_yvl_fsendpt6_len);
+ afs_merge_fs_addr6(alist, bp + 1, ntohl(bp[5]));
+ bp += 6;
+ break;
+ default:
+ return afs_protocol_error(call, afs_eproto_yvl_fsendpt_type);
+ }
+
+ /* Got either the type of the next entry or the count of
+ * volEndpoints if no more fsEndpoints.
+ */
+ call->count2 = ntohl(*bp++);
+
+ call->count--;
+ if (call->count > 0)
+ goto next_fsendpoint;
+
+ extract_volendpoints:
+ /* Extract the list of volEndpoints. */
+ call->count = call->count2;
+ if (!call->count)
+ goto end;
+ if (call->count > YFS_MAXENDPOINTS)
+ return afs_protocol_error(call, afs_eproto_yvl_vlendpt_type);
+
+ afs_extract_to_buf(call, 1 * sizeof(__be32));
+ call->unmarshall = 3;
+
+ /* Extract the type of volEndpoints[0]. Normally we would
+ * extract the type of the next endpoint when we extract the
+ * data of the current one, but this is the first...
+ */
+ fallthrough;
+ case 3:
+ ret = afs_extract_data(call, true);
+ if (ret < 0)
+ return ret;
+
+ bp = call->buffer;
+
+ next_volendpoint:
+ call->count2 = ntohl(*bp++);
+ switch (call->count2) {
+ case YFS_ENDPOINT_IPV4:
+ size = sizeof(__be32) * (1 + 1 + 1);
+ break;
+ case YFS_ENDPOINT_IPV6:
+ size = sizeof(__be32) * (1 + 4 + 1);
+ break;
+ default:
+ return afs_protocol_error(call, afs_eproto_yvl_vlendpt_type);
+ }
+
+ if (call->count > 1)
+ size += sizeof(__be32); /* Get next type too */
+ afs_extract_to_buf(call, size);
+ call->unmarshall = 4;
+
+ fallthrough; /* and extract volEndpoints[] entries */
+ case 4:
+ ret = afs_extract_data(call, true);
+ if (ret < 0)
+ return ret;
+
+ bp = call->buffer;
+ switch (call->count2) {
+ case YFS_ENDPOINT_IPV4:
+ if (ntohl(bp[0]) != sizeof(__be32) * 2)
+ return afs_protocol_error(
+ call, afs_eproto_yvl_vlendpt4_len);
+ bp += 3;
+ break;
+ case YFS_ENDPOINT_IPV6:
+ if (ntohl(bp[0]) != sizeof(__be32) * 5)
+ return afs_protocol_error(
+ call, afs_eproto_yvl_vlendpt6_len);
+ bp += 6;
+ break;
+ default:
+ return afs_protocol_error(call, afs_eproto_yvl_vlendpt_type);
+ }
+
+ /* Got either the type of the next entry or the count of
+ * volEndpoints if no more fsEndpoints.
+ */
+ call->count--;
+ if (call->count > 0)
+ goto next_volendpoint;
+
+ end:
+ afs_extract_discard(call, 0);
+ call->unmarshall = 5;
+
+ fallthrough; /* Done */
+ case 5:
+ ret = afs_extract_data(call, false);
+ if (ret < 0)
+ return ret;
+ call->unmarshall = 6;
+ fallthrough;
+
+ case 6:
+ break;
+ }
+
+ _leave(" = 0 [done]");
+ return 0;
+}
+
+/*
+ * YFSVL.GetEndpoints operation type.
+ */
+static const struct afs_call_type afs_YFSVLGetEndpoints = {
+ .name = "YFSVL.GetEndpoints",
+ .op = afs_YFSVL_GetEndpoints,
+ .deliver = afs_deliver_yfsvl_get_endpoints,
+ .destructor = afs_vl_get_addrs_u_destructor,
+};
+
+/*
+ * Dispatch an operation to get the addresses for a server, where the server is
+ * nominated by UUID.
+ */
+struct afs_addr_list *afs_yfsvl_get_endpoints(struct afs_vl_cursor *vc,
+ const uuid_t *uuid)
+{
+ struct afs_call *call;
+ struct afs_net *net = vc->cell->net;
+ __be32 *bp;
+
+ _enter("");
+
+ call = afs_alloc_flat_call(net, &afs_YFSVLGetEndpoints,
+ sizeof(__be32) * 2 + sizeof(*uuid),
+ sizeof(struct in6_addr) + sizeof(__be32) * 3);
+ if (!call)
+ return ERR_PTR(-ENOMEM);
+
+ call->key = vc->key;
+ call->ret_alist = NULL;
+ call->max_lifespan = AFS_VL_MAX_LIFESPAN;
+
+ /* Marshall the parameters */
+ bp = call->request;
+ *bp++ = htonl(YVLGETENDPOINTS);
+ *bp++ = htonl(YFS_SERVER_UUID);
+ memcpy(bp, uuid, sizeof(*uuid)); /* Type opr_uuid */
+
+ trace_afs_make_vl_call(call);
+ 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++;
+
+ fallthrough; /* 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++;
+
+ fallthrough; /* 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++;
+
+ fallthrough; /* 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);
+}