Here's one last patch for the merge window. It allows the cluster stack to
negotiate a common protocol version with mounting nodes, as opposed to
requiring an exact match as we do today. The patch itself requires a
protocol change, so it'd be nice to see this upstream with all the other
network changes we did for 2.6.25. I held this patch back from my initial
pull request so that we could a bit more testing on it.
--Mark
Please pull from 'upstream-linus' branch of
git://git.kernel.org/pub/scm/linux/kernel/git/mfasheh/ocfs2.git upstream-linus
to receive the following updates:
fs/ocfs2/cluster/tcp_internal.h | 11 ++-
fs/ocfs2/dlm/dlmapi.h | 7 +-
fs/ocfs2/dlm/dlmcommon.h | 24 +++++-
fs/ocfs2/dlm/dlmdomain.c | 195 +++++++++++++++++++++++++++++++++-----
fs/ocfs2/dlm/dlmfs.c | 15 +++-
fs/ocfs2/dlm/userdlm.c | 5 +-
fs/ocfs2/dlm/userdlm.h | 3 +-
fs/ocfs2/dlmglue.c | 29 ++++++-
fs/ocfs2/dlmglue.h | 1 +
fs/ocfs2/ocfs2.h | 1 +
fs/ocfs2/ocfs2_lockingver.h | 30 ++++++
fs/ocfs2/super.c | 1 +
12 files changed, 288 insertions(+), 34 deletions(-)
create mode 100644 fs/ocfs2/ocfs2_lockingver.h
Joel Becker (1):
ocfs2: Negotiate locking protocol versions.
diff --git a/fs/ocfs2/cluster/tcp_internal.h b/fs/ocfs2/cluster/tcp_internal.h
index b2e832a..d25b9af 100644
--- a/fs/ocfs2/cluster/tcp_internal.h
+++ b/fs/ocfs2/cluster/tcp_internal.h
@@ -38,6 +38,15 @@
* locking semantics of the file system using the protocol. It should
* be somewhere else, I'm sure, but right now it isn't.
*
+ * With version 11, we separate out the filesystem locking portion. The
+ * filesystem now has a major.minor version it negotiates. Version 11
+ * introduces this negotiation to the o2dlm protocol, and as such the
+ * version here in tcp_internal.h should not need to be bumped for
+ * filesystem locking changes.
+ *
+ * New in version 11
+ * - Negotiation of filesystem locking in the dlm join.
+ *
* New in version 10:
* - Meta/data locks combined
*
@@ -66,7 +75,7 @@
* - full 64 bit i_size in the metadata lock lvbs
* - introduction of "rw" lock and pushing meta/data locking down
*/
-#define O2NET_PROTOCOL_VERSION 10ULL
+#define O2NET_PROTOCOL_VERSION 11ULL
struct o2net_handshake {
__be64 protocol_version;
__be64 connector_id;
diff --git a/fs/ocfs2/dlm/dlmapi.h b/fs/ocfs2/dlm/dlmapi.h
index cfd5cb6..b5786a7 100644
--- a/fs/ocfs2/dlm/dlmapi.h
+++ b/fs/ocfs2/dlm/dlmapi.h
@@ -193,7 +193,12 @@ enum dlm_status dlmunlock(struct dlm_ctxt *dlm,
dlm_astunlockfunc_t *unlockast,
void *data);
-struct dlm_ctxt * dlm_register_domain(const char *domain, u32 key);
+struct dlm_protocol_version {
+ u8 pv_major;
+ u8 pv_minor;
+};
+struct dlm_ctxt * dlm_register_domain(const char *domain, u32 key,
+ struct dlm_protocol_version *fs_proto);
void dlm_unregister_domain(struct dlm_ctxt *dlm);
diff --git a/fs/ocfs2/dlm/dlmcommon.h b/fs/ocfs2/dlm/dlmcommon.h
index e90b92f..9843ee1 100644
--- a/fs/ocfs2/dlm/dlmcommon.h
+++ b/fs/ocfs2/dlm/dlmcommon.h
@@ -142,6 +142,12 @@ struct dlm_ctxt
spinlock_t work_lock;
struct list_head dlm_domain_handlers;
struct list_head dlm_eviction_callbacks;
+
+ /* The filesystem specifies this at domain registration. We
+ * cache it here to know what to tell other nodes. */
+ struct dlm_protocol_version fs_locking_proto;
+ /* This is the inter-dlm communication version */
+ struct dlm_protocol_version dlm_locking_proto;
};
static inline struct hlist_head *dlm_lockres_hash(struct dlm_ctxt *dlm, unsigned i)
@@ -589,10 +595,24 @@ struct dlm_proxy_ast
#define DLM_PROXY_AST_MAX_LEN (sizeof(struct dlm_proxy_ast)+DLM_LVB_LEN)
#define DLM_MOD_KEY (0x666c6172)
-enum dlm_query_join_response {
+enum dlm_query_join_response_code {
JOIN_DISALLOW = 0,
JOIN_OK,
JOIN_OK_NO_MAP,
+ JOIN_PROTOCOL_MISMATCH,
+};
+
+union dlm_query_join_response {
+ u32 intval;
+ struct {
+ u8 code; /* Response code. dlm_minor and fs_minor
+ are only valid if this is JOIN_OK */
+ u8 dlm_minor; /* The minor version of the protocol the
+ dlm is speaking. */
+ u8 fs_minor; /* The minor version of the protocol the
+ filesystem is speaking. */
+ u8 reserved;
+ } packet;
};
struct dlm_lock_request
@@ -633,6 +653,8 @@ struct dlm_query_join_request
u8 node_idx;
u8 pad1[2];
u8 name_len;
+ struct dlm_protocol_version dlm_proto;
+ struct dlm_protocol_version fs_proto;
u8 domain[O2NM_MAX_NAME_LEN];
u8 node_map[BITS_TO_BYTES(O2NM_MAX_NODES)];
};
diff --git a/fs/ocfs2/dlm/dlmdomain.c b/fs/ocfs2/dlm/dlmdomain.c
index 6954565..638d2eb 100644
--- a/fs/ocfs2/dlm/dlmdomain.c
+++ b/fs/ocfs2/dlm/dlmdomain.c
@@ -123,6 +123,17 @@ DEFINE_SPINLOCK(dlm_domain_lock);
LIST_HEAD(dlm_domains);
static DECLARE_WAIT_QUEUE_HEAD(dlm_domain_events);
+/*
+ * The supported protocol version for DLM communication. Running domains
+ * will have a negotiated version with the same major number and a minor
+ * number equal or smaller. The dlm_ctxt->dlm_locking_proto field should
+ * be used to determine what a running domain is actually using.
+ */
+static const struct dlm_protocol_version dlm_protocol = {
+ .pv_major = 1,
+ .pv_minor = 0,
+};
+
#define DLM_DOMAIN_BACKOFF_MS 200
static int dlm_query_join_handler(struct o2net_msg *msg, u32 len, void *data,
@@ -133,6 +144,8 @@ static int dlm_cancel_join_handler(struct o2net_msg *msg, u32 len, void *data,
void **ret_data);
static int dlm_exit_domain_handler(struct o2net_msg *msg, u32 len, void *data,
void **ret_data);
+static int dlm_protocol_compare(struct dlm_protocol_version *existing,
+ struct dlm_protocol_version *request);
static void dlm_unregister_domain_handlers(struct dlm_ctxt *dlm);
@@ -668,11 +681,45 @@ void dlm_unregister_domain(struct dlm_ctxt *dlm)
}
EXPORT_SYMBOL_GPL(dlm_unregister_domain);
+static int dlm_query_join_proto_check(char *proto_type, int node,
+ struct dlm_protocol_version *ours,
+ struct dlm_protocol_version *request)
+{
+ int rc;
+ struct dlm_protocol_version proto = *request;
+
+ if (!dlm_protocol_compare(ours, &proto)) {
+ mlog(0,
+ "node %u wanted to join with %s locking protocol "
+ "%u.%u, we respond with %u.%u\n",
+ node, proto_type,
+ request->pv_major,
+ request->pv_minor,
+ proto.pv_major, proto.pv_minor);
+ request->pv_minor = proto.pv_minor;
+ rc = 0;
+ } else {
+ mlog(ML_NOTICE,
+ "Node %u wanted to join with %s locking "
+ "protocol %u.%u, but we have %u.%u, disallowing\n",
+ node, proto_type,
+ request->pv_major,
+ request->pv_minor,
+ ours->pv_major,
+ ours->pv_minor);
+ rc = 1;
+ }
+
+ return rc;
+}
+
static int dlm_query_join_handler(struct o2net_msg *msg, u32 len, void *data,
void **ret_data)
{
struct dlm_query_join_request *query;
- enum dlm_query_join_response response;
+ union dlm_query_join_response response = {
+ .packet.code = JOIN_DISALLOW,
+ };
struct dlm_ctxt *dlm = NULL;
u8 nodenum;
@@ -690,11 +737,11 @@ static int dlm_query_join_handler(struct o2net_msg *msg, u32 len, void *data,
mlog(0, "node %u is not in our live map yet\n",
query->node_idx);
- response = JOIN_DISALLOW;
+ response.packet.code = JOIN_DISALLOW;
goto respond;
}
- response = JOIN_OK_NO_MAP;
+ response.packet.code = JOIN_OK_NO_MAP;
spin_lock(&dlm_domain_lock);
dlm = __dlm_lookup_domain_full(query->domain, query->name_len);
@@ -713,7 +760,7 @@ static int dlm_query_join_handler(struct o2net_msg *msg, u32 len, void *data,
mlog(0, "disallow join as node %u does not "
"have node %u in its nodemap\n",
query->node_idx, nodenum);
- response = JOIN_DISALLOW;
+ response.packet.code = JOIN_DISALLOW;
goto unlock_respond;
}
}
@@ -733,30 +780,48 @@ static int dlm_query_join_handler(struct o2net_msg *msg, u32 len, void *data,
/*If this is a brand new context and we
* haven't started our join process yet, then
* the other node won the race. */
- response = JOIN_OK_NO_MAP;
+ response.packet.code = JOIN_OK_NO_MAP;
} else if (dlm->joining_node != DLM_LOCK_RES_OWNER_UNKNOWN) {
/* Disallow parallel joins. */
- response = JOIN_DISALLOW;
+ response.packet.code = JOIN_DISALLOW;
} else if (dlm->reco.state & DLM_RECO_STATE_ACTIVE) {
mlog(0, "node %u trying to join, but recovery "
"is ongoing.\n", bit);
- response = JOIN_DISALLOW;
+ response.packet.code = JOIN_DISALLOW;
} else if (test_bit(bit, dlm->recovery_map)) {
mlog(0, "node %u trying to join, but it "
"still needs recovery.\n", bit);
- response = JOIN_DISALLOW;
+ response.packet.code = JOIN_DISALLOW;
} else if (test_bit(bit, dlm->domain_map)) {
mlog(0, "node %u trying to join, but it "
"is still in the domain! needs recovery?\n",
bit);
- response = JOIN_DISALLOW;
+ response.packet.code = JOIN_DISALLOW;
} else {
/* Alright we're fully a part of this domain
* so we keep some state as to who's joining
* and indicate to him that needs to be fixed
* up. */
- response = JOIN_OK;
- __dlm_set_joining_node(dlm, query->node_idx);
+
+ /* Make sure we speak compatible locking protocols. */
+ if (dlm_query_join_proto_check("DLM", bit,
+ &dlm->dlm_locking_proto,
+ &query->dlm_proto)) {
+ response.packet.code =
+ JOIN_PROTOCOL_MISMATCH;
+ } else if (dlm_query_join_proto_check("fs", bit,
+ &dlm->fs_locking_proto,
+ &query->fs_proto)) {
+ response.packet.code =
+ JOIN_PROTOCOL_MISMATCH;
+ } else {
+ response.packet.dlm_minor =
+ query->dlm_proto.pv_minor;
+ response.packet.fs_minor =
+ query->fs_proto.pv_minor;
+ response.packet.code = JOIN_OK;
+ __dlm_set_joining_node(dlm, query->node_idx);
+ }
}
spin_unlock(&dlm->spinlock);
@@ -765,9 +830,9 @@ unlock_respond:
spin_unlock(&dlm_domain_lock);
respond:
- mlog(0, "We respond with %u\n", response);
+ mlog(0, "We respond with %u\n", response.packet.code);
- return response;
+ return response.intval;
}
static int dlm_assert_joined_handler(struct o2net_msg *msg, u32 len, void *data,
@@ -899,10 +964,11 @@ static int dlm_send_join_cancels(struct dlm_ctxt *dlm,
static int dlm_request_join(struct dlm_ctxt *dlm,
int node,
- enum dlm_query_join_response *response)
+ enum dlm_query_join_response_code *response)
{
- int status, retval;
+ int status;
struct dlm_query_join_request join_msg;
+ union dlm_query_join_response join_resp;
mlog(0, "querying node %d\n", node);
@@ -910,12 +976,15 @@ static int dlm_request_join(struct dlm_ctxt *dlm,
join_msg.node_idx = dlm->node_num;
join_msg.name_len = strlen(dlm->name);
memcpy(join_msg.domain, dlm->name, join_msg.name_len);
+ join_msg.dlm_proto = dlm->dlm_locking_proto;
+ join_msg.fs_proto = dlm->fs_locking_proto;
/* copy live node map to join message */
byte_copymap(join_msg.node_map, dlm->live_nodes_map, O2NM_MAX_NODES);
status = o2net_send_message(DLM_QUERY_JOIN_MSG, DLM_MOD_KEY, &join_msg,
- sizeof(join_msg), node, &retval);
+ sizeof(join_msg), node,
+ &join_resp.intval);
if (status < 0 && status != -ENOPROTOOPT) {
mlog_errno(status);
goto bail;
@@ -928,14 +997,41 @@ static int dlm_request_join(struct dlm_ctxt *dlm,
if (status == -ENOPROTOOPT) {
status = 0;
*response = JOIN_OK_NO_MAP;
- } else if (retval == JOIN_DISALLOW ||
- retval == JOIN_OK ||
- retval == JOIN_OK_NO_MAP) {
- *response = retval;
+ } else if (join_resp.packet.code == JOIN_DISALLOW ||
+ join_resp.packet.code == JOIN_OK_NO_MAP) {
+ *response = join_resp.packet.code;
+ } else if (join_resp.packet.code == JOIN_PROTOCOL_MISMATCH) {
+ mlog(ML_NOTICE,
+ "This node requested DLM locking protocol %u.%u and "
+ "filesystem locking protocol %u.%u. At least one of "
+ "the protocol versions on node %d is not compatible, "
+ "disconnecting\n",
+ dlm->dlm_locking_proto.pv_major,
+ dlm->dlm_locking_proto.pv_minor,
+ dlm->fs_locking_proto.pv_major,
+ dlm->fs_locking_proto.pv_minor,
+ node);
+ status = -EPROTO;
+ *response = join_resp.packet.code;
+ } else if (join_resp.packet.code == JOIN_OK) {
+ *response = join_resp.packet.code;
+ /* Use the same locking protocol as the remote node */
+ dlm->dlm_locking_proto.pv_minor =
+ join_resp.packet.dlm_minor;
+ dlm->fs_locking_proto.pv_minor =
+ join_resp.packet.fs_minor;
+ mlog(0,
+ "Node %d responds JOIN_OK with DLM locking protocol "
+ "%u.%u and fs locking protocol %u.%u\n",
+ node,
+ dlm->dlm_locking_proto.pv_major,
+ dlm->dlm_locking_proto.pv_minor,
+ dlm->fs_locking_proto.pv_major,
+ dlm->fs_locking_proto.pv_minor);
} else {
status = -EINVAL;
- mlog(ML_ERROR, "invalid response %d from node %u\n", retval,
- node);
+ mlog(ML_ERROR, "invalid response %d from node %u\n",
+ join_resp.packet.code, node);
}
mlog(0, "status %d, node %d response is %d\n", status, node,
@@ -1008,7 +1104,7 @@ struct domain_join_ctxt {
static int dlm_should_restart_join(struct dlm_ctxt *dlm,
struct domain_join_ctxt *ctxt,
- enum dlm_query_join_response response)
+ enum dlm_query_join_response_code response)
{
int ret;
@@ -1034,7 +1130,7 @@ static int dlm_try_to_join_domain(struct dlm_ctxt *dlm)
{
int status = 0, tmpstat, node;
struct domain_join_ctxt *ctxt;
- enum dlm_query_join_response response = JOIN_DISALLOW;
+ enum dlm_query_join_response_code response = JOIN_DISALLOW;
mlog_entry("%p", dlm);
@@ -1450,10 +1546,38 @@ leave:
}
/*
- * dlm_register_domain: one-time setup per "domain"
+ * Compare a requested locking protocol version against the current one.
+ *
+ * If the major numbers are different, they are incompatible.
+ * If the current minor is greater than the request, they are incompatible.
+ * If the current minor is less than or equal to the request, they are
+ * compatible, and the requester should run at the current minor version.
+ */
+static int dlm_protocol_compare(struct dlm_protocol_version *existing,
+ struct dlm_protocol_version *request)
+{
+ if (existing->pv_major != request->pv_major)
+ return 1;
+
+ if (existing->pv_minor > request->pv_minor)
+ return 1;
+
+ if (existing->pv_minor < request->pv_minor)
+ request->pv_minor = existing->pv_minor;
+
+ return 0;
+}
+
+/*
+ * dlm_register_domain: one-time setup per "domain".
+ *
+ * The filesystem passes in the requested locking version via proto.
+ * If registration was successful, proto will contain the negotiated
+ * locking protocol.
*/
struct dlm_ctxt * dlm_register_domain(const char *domain,
- u32 key)
+ u32 key,
+ struct dlm_protocol_version *fs_proto)
{
int ret;
struct dlm_ctxt *dlm = NULL;
@@ -1496,6 +1620,15 @@ retry:
goto retry;
}
+ if (dlm_protocol_compare(&dlm->fs_locking_proto, fs_proto)) {
+ mlog(ML_ERROR,
+ "Requested locking protocol version is not "
+ "compatible with already registered domain "
+ "\"%s\"\n", domain);
+ ret = -EPROTO;
+ goto leave;
+ }
+
__dlm_get(dlm);
dlm->num_joins++;
@@ -1526,6 +1659,13 @@ retry:
list_add_tail(&dlm->list, &dlm_domains);
spin_unlock(&dlm_domain_lock);
+ /*
+ * Pass the locking protocol version into the join. If the join
+ * succeeds, it will have the negotiated protocol set.
+ */
+ dlm->dlm_locking_proto = dlm_protocol;
+ dlm->fs_locking_proto = *fs_proto;
+
ret = dlm_join_domain(dlm);
if (ret) {
mlog_errno(ret);
@@ -1533,6 +1673,9 @@ retry:
goto leave;
}
+ /* Tell the caller what locking protocol we negotiated */
+ *fs_proto = dlm->fs_locking_proto;
+
ret = 0;
leave:
if (new_ctxt)
diff --git a/fs/ocfs2/dlm/dlmfs.c b/fs/ocfs2/dlm/dlmfs.c
index 6639baa..61a000f 100644
--- a/fs/ocfs2/dlm/dlmfs.c
+++ b/fs/ocfs2/dlm/dlmfs.c
@@ -60,6 +60,8 @@
#define MLOG_MASK_PREFIX ML_DLMFS
#include "cluster/masklog.h"
+#include "ocfs2_lockingver.h"
+
static const struct super_operations dlmfs_ops;
static const struct file_operations dlmfs_file_operations;
static const struct inode_operations dlmfs_dir_inode_operations;
@@ -70,6 +72,16 @@ static struct kmem_cache *dlmfs_inode_cache;
struct workqueue_struct *user_dlm_worker;
/*
+ * This is the userdlmfs locking protocol version.
+ *
+ * See fs/ocfs2/dlmglue.c for more details on locking versions.
+ */
+static const struct dlm_protocol_version user_locking_protocol = {
+ .pv_major = OCFS2_LOCKING_PROTOCOL_MAJOR,
+ .pv_minor = OCFS2_LOCKING_PROTOCOL_MINOR,
+};
+
+/*
* decodes a set of open flags into a valid lock level and a set of flags.
* returns < 0 if we have invalid flags
* flags which mean something to us:
@@ -416,6 +428,7 @@ static int dlmfs_mkdir(struct inode * dir,
struct qstr *domain = &dentry->d_name;
struct dlmfs_inode_private *ip;
struct dlm_ctxt *dlm;
+ struct dlm_protocol_version proto = user_locking_protocol;
mlog(0, "mkdir %.*s\n", domain->len, domain->name);
@@ -435,7 +448,7 @@ static int dlmfs_mkdir(struct inode * dir,
ip = DLMFS_I(inode);
- dlm = user_dlm_register_context(domain);
+ dlm = user_dlm_register_context(domain, &proto);
if (IS_ERR(dlm)) {
status = PTR_ERR(dlm);
mlog(ML_ERROR, "Error %d could not register domain \"%.*s\"\n",
diff --git a/fs/ocfs2/dlm/userdlm.c b/fs/ocfs2/dlm/userdlm.c
index 7d2f578..4cb1d3d 100644
--- a/fs/ocfs2/dlm/userdlm.c
+++ b/fs/ocfs2/dlm/userdlm.c
@@ -645,7 +645,8 @@ bail:
return status;
}
-struct dlm_ctxt *user_dlm_register_context(struct qstr *name)
+struct dlm_ctxt *user_dlm_register_context(struct qstr *name,
+ struct dlm_protocol_version *proto)
{
struct dlm_ctxt *dlm;
u32 dlm_key;
@@ -661,7 +662,7 @@ struct dlm_ctxt *user_dlm_register_context(struct qstr *name)
snprintf(domain, name->len + 1, "%.*s", name->len, name->name);
- dlm = dlm_register_domain(domain, dlm_key);
+ dlm = dlm_register_domain(domain, dlm_key, proto);
if (IS_ERR(dlm))
mlog_errno(PTR_ERR(dlm));
diff --git a/fs/ocfs2/dlm/userdlm.h b/fs/ocfs2/dlm/userdlm.h
index c400e93..39ec277 100644
--- a/fs/ocfs2/dlm/userdlm.h
+++ b/fs/ocfs2/dlm/userdlm.h
@@ -83,7 +83,8 @@ void user_dlm_write_lvb(struct inode *inode,
void user_dlm_read_lvb(struct inode *inode,
char *val,
unsigned int len);
-struct dlm_ctxt *user_dlm_register_context(struct qstr *name);
+struct dlm_ctxt *user_dlm_register_context(struct qstr *name,
+ struct dlm_protocol_version *proto);
void user_dlm_unregister_context(struct dlm_ctxt *dlm);
struct dlmfs_inode_private {
diff --git a/fs/ocfs2/dlmglue.c b/fs/ocfs2/dlmglue.c
index 3867244..351130c 100644
--- a/fs/ocfs2/dlmglue.c
+++ b/fs/ocfs2/dlmglue.c
@@ -43,6 +43,7 @@
#include <cluster/masklog.h>
#include "ocfs2.h"
+#include "ocfs2_lockingver.h"
#include "alloc.h"
#include "dcache.h"
@@ -258,6 +259,31 @@ static struct ocfs2_lock_res_ops ocfs2_flock_lops = {
.flags = 0,
};
+/*
+ * This is the filesystem locking protocol version.
+ *
+ * Whenever the filesystem does new things with locks (adds or removes a
+ * lock, orders them differently, does different things underneath a lock),
+ * the version must be changed. The protocol is negotiated when joining
+ * the dlm domain. A node may join the domain if its major version is
+ * identical to all other nodes and its minor version is greater than
+ * or equal to all other nodes. When its minor version is greater than
+ * the other nodes, it will run at the minor version specified by the
+ * other nodes.
+ *
+ * If a locking change is made that will not be compatible with older
+ * versions, the major number must be increased and the minor version set
+ * to zero. If a change merely adds a behavior that can be disabled when
+ * speaking to older versions, the minor version must be increased. If a
+ * change adds a fully backwards compatible change (eg, LVB changes that
+ * are just ignored by older versions), the version does not need to be
+ * updated.
+ */
+const struct dlm_protocol_version ocfs2_locking_protocol = {
+ .pv_major = OCFS2_LOCKING_PROTOCOL_MAJOR,
+ .pv_minor = OCFS2_LOCKING_PROTOCOL_MINOR,
+};
+
static inline int ocfs2_is_inode_lock(struct ocfs2_lock_res *lockres)
{
return lockres->l_type == OCFS2_LOCK_TYPE_META ||
@@ -2506,7 +2532,8 @@ int ocfs2_dlm_init(struct ocfs2_super *osb)
dlm_key = crc32_le(0, osb->uuid_str, strlen(osb->uuid_str));
/* for now, uuid == domain */
- dlm = dlm_register_domain(osb->uuid_str, dlm_key);
+ dlm = dlm_register_domain(osb->uuid_str, dlm_key,
+ &osb->osb_locking_proto);
if (IS_ERR(dlm)) {
status = PTR_ERR(dlm);
mlog_errno(status);
diff --git a/fs/ocfs2/dlmglue.h b/fs/ocfs2/dlmglue.h
index 5f17243..1d5b069 100644
--- a/fs/ocfs2/dlmglue.h
+++ b/fs/ocfs2/dlmglue.h
@@ -116,4 +116,5 @@ void ocfs2_wake_downconvert_thread(struct ocfs2_super *osb);
struct ocfs2_dlm_debug *ocfs2_new_dlm_debug(void);
void ocfs2_put_dlm_debug(struct ocfs2_dlm_debug *dlm_debug);
+extern const struct dlm_protocol_version ocfs2_locking_protocol;
#endif /* DLMGLUE_H */
diff --git a/fs/ocfs2/ocfs2.h b/fs/ocfs2/ocfs2.h
index d084805..e8b7292 100644
--- a/fs/ocfs2/ocfs2.h
+++ b/fs/ocfs2/ocfs2.h
@@ -251,6 +251,7 @@ struct ocfs2_super
struct ocfs2_lock_res osb_rename_lockres;
struct dlm_eviction_cb osb_eviction_cb;
struct ocfs2_dlm_debug *osb_dlm_debug;
+ struct dlm_protocol_version osb_locking_proto;
struct dentry *osb_debug_root;
diff --git a/fs/ocfs2/ocfs2_lockingver.h b/fs/ocfs2/ocfs2_lockingver.h
new file mode 100644
index 0000000..82d5eea
--- /dev/null
+++ b/fs/ocfs2/ocfs2_lockingver.h
@@ -0,0 +1,30 @@
+/* -*- mode: c; c-basic-offset: 8; -*-
+ * vim: noexpandtab sw=8 ts=8 sts=0:
+ *
+ * ocfs2_lockingver.h
+ *
+ * Defines OCFS2 Locking version values.
+ *
+ * Copyright (C) 2008 Oracle. All rights reserved.
+ *
+ * This program is free software; you can redistribute it and/or
+ * modify it under the terms of the GNU General Public
+ * License, version 2, as published by the Free Software Foundation.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
+ * General Public License for more details.
+ */
+
+#ifndef OCFS2_LOCKINGVER_H
+#define OCFS2_LOCKINGVER_H
+
+/*
+ * The protocol version for ocfs2 cluster locking. See dlmglue.c for
+ * more details.
+ */
+#define OCFS2_LOCKING_PROTOCOL_MAJOR 1
+#define OCFS2_LOCKING_PROTOCOL_MINOR 0
+
+#endif /* OCFS2_LOCKINGVER_H */
diff --git a/fs/ocfs2/super.c b/fs/ocfs2/super.c
index 01fe40e..bec75af 100644
--- a/fs/ocfs2/super.c
+++ b/fs/ocfs2/super.c
@@ -1355,6 +1355,7 @@ static int ocfs2_initialize_super(struct super_block *sb,
sb->s_fs_info = osb;
sb->s_op = &ocfs2_sops;
sb->s_export_op = &ocfs2_export_ops;
+ osb->osb_locking_proto = ocfs2_locking_protocol;
sb->s_time_gran = 1;
sb->s_flags |= MS_NOATIME;
/* this is needed to support O_LARGEFILE */
On Thu, 7 Feb 2008 12:09:44 -0800
Mark Fasheh <[email protected]> wrote:
> /*
> - * dlm_register_domain: one-time setup per "domain"
> + * Compare a requested locking protocol version against the current one.
> + *
> + * If the major numbers are different, they are incompatible.
> + * If the current minor is greater than the request, they are incompatible.
> + * If the current minor is less than or equal to the request, they are
> + * compatible, and the requester should run at the current minor version.
> + */
> +static int dlm_protocol_compare(struct dlm_protocol_version *existing,
> + struct dlm_protocol_version *request)
> +{
> + if (existing->pv_major != request->pv_major)
> + return 1;
> +
> + if (existing->pv_minor > request->pv_minor)
> + return 1;
> +
> + if (existing->pv_minor < request->pv_minor)
> + request->pv_minor = existing->pv_minor;
> +
> + return 0;
> +}
> +
It's somewhat obnoxious that what appears to be a straightforward
compare-two-things-and-return-result function will actually modify one of
the things which it is allegedly comparing.
Please integrate checkpatch into your processes - this one had a few little
glitches.
On Thu, Feb 07, 2008 at 12:47:45PM -0800, Andrew Morton wrote:
> On Thu, 7 Feb 2008 12:09:44 -0800
> Mark Fasheh <[email protected]> wrote:
>
> > /*
> > - * dlm_register_domain: one-time setup per "domain"
> > + * Compare a requested locking protocol version against the current one.
> > + *
> > + * If the major numbers are different, they are incompatible.
> > + * If the current minor is greater than the request, they are incompatible.
> > + * If the current minor is less than or equal to the request, they are
> > + * compatible, and the requester should run at the current minor version.
> > + */
> > +static int dlm_protocol_compare(struct dlm_protocol_version *existing,
> > + struct dlm_protocol_version *request)
> > +{
> > + if (existing->pv_major != request->pv_major)
> > + return 1;
> > +
> > + if (existing->pv_minor > request->pv_minor)
> > + return 1;
> > +
> > + if (existing->pv_minor < request->pv_minor)
> > + request->pv_minor = existing->pv_minor;
> > +
> > + return 0;
> > +}
> > +
>
> It's somewhat obnoxious that what appears to be a straightforward
> compare-two-things-and-return-result function will actually modify one of
> the things which it is allegedly comparing.
Yeah, a better name would probably help with readability. Joel, how about
dlm_protocol_compare_and_set()?
> Please integrate checkpatch into your processes - this one had a few little
> glitches.
FWIW - I've run all patches through checkpatch.pl since your last review.
This one went through a couple cycles of checkpatch actually :) There's
three warnings that I get:
ERROR: "foo * bar" should be "foo *bar"
#70: FILE: fs/ocfs2/dlm/dlmapi.h:200:
+struct dlm_ctxt * dlm_register_domain(const char *domain, u32 key,
WARNING: line over 80 characters
#269: FILE: fs/ocfs2/dlm/dlmdomain.c:813:
+
#&dlm->fs_locking_proto,
WARNING: line over 80 characters
#270: FILE: fs/ocfs2/dlm/dlmdomain.c:814:
+
#&query->fs_proto)) {
total: 1 errors, 2 warnings, 569 lines checked
The "foo * bar" one is from existing code which got moved, and I felt that
leaving them unmodified was cleaner from a patch-reading perspective.
The over 80 characters warnings were ignored as the code seemed more
readable as-is.
I guess a lot of this can be subjective though, so I can be super strict if
you really feel it's necessary.
Thanks,
--Mark
--
Mark Fasheh
Principal Software Developer, Oracle
[email protected]
On Thu, 7 Feb 2008 13:37:15 -0800
Mark Fasheh <[email protected]> wrote:
> > Please integrate checkpatch into your processes - this one had a few little
> > glitches.
>
> FWIW - I've run all patches through checkpatch.pl since your last review.
cool, thanks.
> This one went through a couple cycles of checkpatch actually :) There's
> three warnings that I get:
>
> ERROR: "foo * bar" should be "foo *bar"
> #70: FILE: fs/ocfs2/dlm/dlmapi.h:200:
> +struct dlm_ctxt * dlm_register_domain(const char *domain, u32 key,
>
> WARNING: line over 80 characters
> #269: FILE: fs/ocfs2/dlm/dlmdomain.c:813:
> +
> #&dlm->fs_locking_proto,
>
> WARNING: line over 80 characters
> #270: FILE: fs/ocfs2/dlm/dlmdomain.c:814:
> +
> #&query->fs_proto)) {
>
> total: 1 errors, 2 warnings, 569 lines checked
>
>
> The "foo * bar" one is from existing code which got moved, and I felt that
> leaving them unmodified was cleaner from a patch-reading perspective.
I tend to clean those things up as we go, because it's a free patch.
otoh I see that dlm style is presently space-after-asterisk so there's not
a lot of point in fixing just one of them.
> The over 80 characters warnings were ignored as the code seemed more
> readable as-is.
yes, I tend to ignore those warnings unless the mess is really gratuitous or
if the surrounding code has obviously made some effort to avoid the problem.
> I guess a lot of this can be subjective though, so I can be super strict if
> you really feel it's necessary.
No, you shouldn't view checkpatch as a things-i-must-do. It is a
things-i-might-have-missed tool. If you _meant_ things to be that way then
fine, ignore it.
On Thu, Feb 07, 2008 at 01:37:15PM -0800, Mark Fasheh wrote:
> On Thu, Feb 07, 2008 at 12:47:45PM -0800, Andrew Morton wrote:
> > On Thu, 7 Feb 2008 12:09:44 -0800
> > Mark Fasheh <[email protected]> wrote:
> >
> > > +static int dlm_protocol_compare(struct dlm_protocol_version *existing,
> > > + struct dlm_protocol_version *request)
> >
> > It's somewhat obnoxious that what appears to be a straightforward
> > compare-two-things-and-return-result function will actually modify one of
> > the things which it is allegedly comparing.
>
> Yeah, a better name would probably help with readability. Joel, how about
> dlm_protocol_compare_and_set()?
Even better is to move the update outside the function. What do
we think of the following?
>From d667a08d73cd6659219d21cc57f67882f46e42d1 Mon Sep 17 00:00:00 2001
From: Joel Becker <[email protected]>
Date: Thu, 7 Feb 2008 14:25:11 -0800
Subject: [PATCH] ocfs2: Clean up locking protocol negotiation.
The comparison functions for protocol negotiation (introduced in commit
d24fbcda0c4988322949df3d759f1cfb32b32953) were confusing.
Separate out the comparison and value update parts.
Signed-off-by: Joel Becker <[email protected]>
---
fs/ocfs2/dlm/dlmdomain.c | 102 ++++++++++++++++++++++------------------------
1 files changed, 49 insertions(+), 53 deletions(-)
diff --git a/fs/ocfs2/dlm/dlmdomain.c b/fs/ocfs2/dlm/dlmdomain.c
index 638d2eb..de802a7 100644
--- a/fs/ocfs2/dlm/dlmdomain.c
+++ b/fs/ocfs2/dlm/dlmdomain.c
@@ -144,8 +144,6 @@ static int dlm_cancel_join_handler(struct o2net_msg *msg, u32 len, void *data,
void **ret_data);
static int dlm_exit_domain_handler(struct o2net_msg *msg, u32 len, void *data,
void **ret_data);
-static int dlm_protocol_compare(struct dlm_protocol_version *existing,
- struct dlm_protocol_version *request);
static void dlm_unregister_domain_handlers(struct dlm_ctxt *dlm);
@@ -681,36 +679,48 @@ void dlm_unregister_domain(struct dlm_ctxt *dlm)
}
EXPORT_SYMBOL_GPL(dlm_unregister_domain);
+/*
+ * Compare a requested locking protocol version against the current one.
+ *
+ * If the major numbers are different, they are incompatible.
+ * If the current minor is greater than the request, they are incompatible.
+ * If the current minor is less than or equal to the request, they are
+ * compatible, and the requester should run at the current minor version.
+ */
+static int dlm_protocol_compatible(struct dlm_protocol_version *existing,
+ struct dlm_protocol_version *request)
+{
+ if (existing->pv_major != request->pv_major)
+ return 0;
+
+ if (existing->pv_minor > request->pv_minor)
+ return 0;
+
+ return 1;
+}
+
static int dlm_query_join_proto_check(char *proto_type, int node,
struct dlm_protocol_version *ours,
struct dlm_protocol_version *request)
{
- int rc;
- struct dlm_protocol_version proto = *request;
+ int compatible = dlm_protocol_compatible(ours, request);
- if (!dlm_protocol_compare(ours, &proto)) {
+ if (compatible)
mlog(0,
"node %u wanted to join with %s locking protocol "
"%u.%u, we respond with %u.%u\n",
node, proto_type,
- request->pv_major,
- request->pv_minor,
- proto.pv_major, proto.pv_minor);
- request->pv_minor = proto.pv_minor;
- rc = 0;
- } else {
+ request->pv_major, request->pv_minor,
+ ours->pv_major, ours->pv_minor);
+ else
mlog(ML_NOTICE,
"Node %u wanted to join with %s locking "
"protocol %u.%u, but we have %u.%u, disallowing\n",
node, proto_type,
- request->pv_major,
- request->pv_minor,
- ours->pv_major,
- ours->pv_minor);
- rc = 1;
- }
+ request->pv_major, request->pv_minor,
+ ours->pv_major, ours->pv_minor);
- return rc;
+ return compatible;
}
static int dlm_query_join_handler(struct o2net_msg *msg, u32 len, void *data,
@@ -806,21 +816,23 @@ static int dlm_query_join_handler(struct o2net_msg *msg, u32 len, void *data,
/* Make sure we speak compatible locking protocols. */
if (dlm_query_join_proto_check("DLM", bit,
&dlm->dlm_locking_proto,
- &query->dlm_proto)) {
- response.packet.code =
- JOIN_PROTOCOL_MISMATCH;
- } else if (dlm_query_join_proto_check("fs", bit,
- &dlm->fs_locking_proto,
- &query->fs_proto)) {
- response.packet.code =
- JOIN_PROTOCOL_MISMATCH;
- } else {
+ &query->dlm_proto) &&
+ dlm_query_join_proto_check("fs", bit,
+ &dlm->fs_locking_proto,
+ &query->fs_proto)) {
+ /*
+ * We're compatible, return our
+ * minor number
+ */
response.packet.dlm_minor =
- query->dlm_proto.pv_minor;
+ dlm->dlm_locking_proto.pv_minor;
response.packet.fs_minor =
- query->fs_proto.pv_minor;
+ dlm->fs_locking_proto.pv_minor;
response.packet.code = JOIN_OK;
__dlm_set_joining_node(dlm, query->node_idx);
+ } else {
+ response.packet.code =
+ JOIN_PROTOCOL_MISMATCH;
}
}
@@ -1546,29 +1558,6 @@ leave:
}
/*
- * Compare a requested locking protocol version against the current one.
- *
- * If the major numbers are different, they are incompatible.
- * If the current minor is greater than the request, they are incompatible.
- * If the current minor is less than or equal to the request, they are
- * compatible, and the requester should run at the current minor version.
- */
-static int dlm_protocol_compare(struct dlm_protocol_version *existing,
- struct dlm_protocol_version *request)
-{
- if (existing->pv_major != request->pv_major)
- return 1;
-
- if (existing->pv_minor > request->pv_minor)
- return 1;
-
- if (existing->pv_minor < request->pv_minor)
- request->pv_minor = existing->pv_minor;
-
- return 0;
-}
-
-/*
* dlm_register_domain: one-time setup per "domain".
*
* The filesystem passes in the requested locking version via proto.
@@ -1620,7 +1609,14 @@ retry:
goto retry;
}
- if (dlm_protocol_compare(&dlm->fs_locking_proto, fs_proto)) {
+ if (dlm_protocol_compatible(&dlm->fs_locking_proto, fs_proto)) {
+ /*
+ * We're compatible, and we run at the minor
+ * number negotiated
+ */
+ fs_proto->pv_minor =
+ dlm->fs_locking_proto.pv_minor;
+ } else {
mlog(ML_ERROR,
"Requested locking protocol version is not "
"compatible with already registered domain "
--
1.5.2.2
--
"Gone to plant a weeping willow
On the bank's green edge it will roll, roll, roll.
Sing a lulaby beside the waters.
Lovers come and go, the river roll, roll, rolls."
Joel Becker
Principal Software Developer
Oracle
E-mail: [email protected]
Phone: (650) 506-8127