[T106][ZXW-22]7520V3SCV2.01.01.02P42U09_VEC_V0.8_AP_VEC origin source commit
Change-Id: Ic6e05d89ecd62fc34f82b23dcf306c93764aec4b
diff --git a/ap/os/linux/linux-3.4.x/fs/nfs/delegation.c b/ap/os/linux/linux-3.4.x/fs/nfs/delegation.c
new file mode 100644
index 0000000..62261de
--- /dev/null
+++ b/ap/os/linux/linux-3.4.x/fs/nfs/delegation.c
@@ -0,0 +1,708 @@
+/*
+ * linux/fs/nfs/delegation.c
+ *
+ * Copyright (C) 2004 Trond Myklebust
+ *
+ * NFS file delegation management
+ *
+ */
+#include <linux/completion.h>
+#include <linux/kthread.h>
+#include <linux/module.h>
+#include <linux/sched.h>
+#include <linux/slab.h>
+#include <linux/spinlock.h>
+
+#include <linux/nfs4.h>
+#include <linux/nfs_fs.h>
+#include <linux/nfs_xdr.h>
+
+#include "nfs4_fs.h"
+#include "delegation.h"
+#include "internal.h"
+
+static void nfs_free_delegation(struct nfs_delegation *delegation)
+{
+ if (delegation->cred) {
+ put_rpccred(delegation->cred);
+ delegation->cred = NULL;
+ }
+ kfree_rcu(delegation, rcu);
+}
+
+/**
+ * nfs_mark_delegation_referenced - set delegation's REFERENCED flag
+ * @delegation: delegation to process
+ *
+ */
+void nfs_mark_delegation_referenced(struct nfs_delegation *delegation)
+{
+ set_bit(NFS_DELEGATION_REFERENCED, &delegation->flags);
+}
+
+/**
+ * nfs_have_delegation - check if inode has a delegation
+ * @inode: inode to check
+ * @flags: delegation types to check for
+ *
+ * Returns one if inode has the indicated delegation, otherwise zero.
+ */
+int nfs_have_delegation(struct inode *inode, fmode_t flags)
+{
+ struct nfs_delegation *delegation;
+ int ret = 0;
+
+ flags &= FMODE_READ|FMODE_WRITE;
+ rcu_read_lock();
+ delegation = rcu_dereference(NFS_I(inode)->delegation);
+ if (delegation != NULL && (delegation->type & flags) == flags) {
+ nfs_mark_delegation_referenced(delegation);
+ ret = 1;
+ }
+ rcu_read_unlock();
+ return ret;
+}
+
+static int nfs_delegation_claim_locks(struct nfs_open_context *ctx, struct nfs4_state *state)
+{
+ struct inode *inode = state->inode;
+ struct file_lock *fl;
+ int status = 0;
+
+ if (inode->i_flock == NULL)
+ goto out;
+
+ /* Protect inode->i_flock using the file locks lock */
+ lock_flocks();
+ for (fl = inode->i_flock; fl != NULL; fl = fl->fl_next) {
+ if (!(fl->fl_flags & (FL_POSIX|FL_FLOCK)))
+ continue;
+ if (nfs_file_open_context(fl->fl_file) != ctx)
+ continue;
+ unlock_flocks();
+ status = nfs4_lock_delegation_recall(state, fl);
+ if (status < 0)
+ goto out;
+ lock_flocks();
+ }
+ unlock_flocks();
+out:
+ return status;
+}
+
+static int nfs_delegation_claim_opens(struct inode *inode, const nfs4_stateid *stateid)
+{
+ struct nfs_inode *nfsi = NFS_I(inode);
+ struct nfs_open_context *ctx;
+ struct nfs4_state *state;
+ int err;
+
+again:
+ spin_lock(&inode->i_lock);
+ list_for_each_entry(ctx, &nfsi->open_files, list) {
+ state = ctx->state;
+ if (state == NULL)
+ continue;
+ if (!test_bit(NFS_DELEGATED_STATE, &state->flags))
+ continue;
+ if (!nfs4_stateid_match(&state->stateid, stateid))
+ continue;
+ get_nfs_open_context(ctx);
+ spin_unlock(&inode->i_lock);
+ err = nfs4_open_delegation_recall(ctx, state, stateid);
+ if (err >= 0)
+ err = nfs_delegation_claim_locks(ctx, state);
+ put_nfs_open_context(ctx);
+ if (err != 0)
+ return err;
+ goto again;
+ }
+ spin_unlock(&inode->i_lock);
+ return 0;
+}
+
+/**
+ * nfs_inode_reclaim_delegation - process a delegation reclaim request
+ * @inode: inode to process
+ * @cred: credential to use for request
+ * @res: new delegation state from server
+ *
+ */
+void nfs_inode_reclaim_delegation(struct inode *inode, struct rpc_cred *cred,
+ struct nfs_openres *res)
+{
+ struct nfs_delegation *delegation;
+ struct rpc_cred *oldcred = NULL;
+
+ rcu_read_lock();
+ delegation = rcu_dereference(NFS_I(inode)->delegation);
+ if (delegation != NULL) {
+ spin_lock(&delegation->lock);
+ if (delegation->inode != NULL) {
+ nfs4_stateid_copy(&delegation->stateid, &res->delegation);
+ delegation->type = res->delegation_type;
+ delegation->maxsize = res->maxsize;
+ oldcred = delegation->cred;
+ delegation->cred = get_rpccred(cred);
+ clear_bit(NFS_DELEGATION_NEED_RECLAIM,
+ &delegation->flags);
+ NFS_I(inode)->delegation_state = delegation->type;
+ spin_unlock(&delegation->lock);
+ rcu_read_unlock();
+ put_rpccred(oldcred);
+ } else {
+ /* We appear to have raced with a delegation return. */
+ spin_unlock(&delegation->lock);
+ rcu_read_unlock();
+ nfs_inode_set_delegation(inode, cred, res);
+ }
+ } else {
+ rcu_read_unlock();
+ }
+}
+
+static int nfs_do_return_delegation(struct inode *inode, struct nfs_delegation *delegation, int issync)
+{
+ int res = 0;
+
+ res = nfs4_proc_delegreturn(inode, delegation->cred, &delegation->stateid, issync);
+ nfs_free_delegation(delegation);
+ return res;
+}
+
+static struct inode *nfs_delegation_grab_inode(struct nfs_delegation *delegation)
+{
+ struct inode *inode = NULL;
+
+ spin_lock(&delegation->lock);
+ if (delegation->inode != NULL)
+ inode = igrab(delegation->inode);
+ spin_unlock(&delegation->lock);
+ return inode;
+}
+
+static struct nfs_delegation *
+nfs_detach_delegation_locked(struct nfs_inode *nfsi,
+ struct nfs_server *server)
+{
+ struct nfs_delegation *delegation =
+ rcu_dereference_protected(nfsi->delegation,
+ lockdep_is_held(&server->nfs_client->cl_lock));
+
+ if (delegation == NULL)
+ goto nomatch;
+
+ spin_lock(&delegation->lock);
+ list_del_rcu(&delegation->super_list);
+ delegation->inode = NULL;
+ nfsi->delegation_state = 0;
+ rcu_assign_pointer(nfsi->delegation, NULL);
+ spin_unlock(&delegation->lock);
+ return delegation;
+nomatch:
+ return NULL;
+}
+
+static struct nfs_delegation *nfs_detach_delegation(struct nfs_inode *nfsi,
+ struct nfs_server *server)
+{
+ struct nfs_client *clp = server->nfs_client;
+ struct nfs_delegation *delegation;
+
+ spin_lock(&clp->cl_lock);
+ delegation = nfs_detach_delegation_locked(nfsi, server);
+ spin_unlock(&clp->cl_lock);
+ return delegation;
+}
+
+/**
+ * nfs_inode_set_delegation - set up a delegation on an inode
+ * @inode: inode to which delegation applies
+ * @cred: cred to use for subsequent delegation processing
+ * @res: new delegation state from server
+ *
+ * Returns zero on success, or a negative errno value.
+ */
+int nfs_inode_set_delegation(struct inode *inode, struct rpc_cred *cred, struct nfs_openres *res)
+{
+ struct nfs_server *server = NFS_SERVER(inode);
+ struct nfs_client *clp = server->nfs_client;
+ struct nfs_inode *nfsi = NFS_I(inode);
+ struct nfs_delegation *delegation, *old_delegation;
+ struct nfs_delegation *freeme = NULL;
+ int status = 0;
+
+ delegation = kmalloc(sizeof(*delegation), GFP_NOFS);
+ if (delegation == NULL)
+ return -ENOMEM;
+ nfs4_stateid_copy(&delegation->stateid, &res->delegation);
+ delegation->type = res->delegation_type;
+ delegation->maxsize = res->maxsize;
+ delegation->change_attr = inode->i_version;
+ delegation->cred = get_rpccred(cred);
+ delegation->inode = inode;
+ delegation->flags = 1<<NFS_DELEGATION_REFERENCED;
+ spin_lock_init(&delegation->lock);
+
+ spin_lock(&clp->cl_lock);
+ old_delegation = rcu_dereference_protected(nfsi->delegation,
+ lockdep_is_held(&clp->cl_lock));
+ if (old_delegation != NULL) {
+ if (nfs4_stateid_match(&delegation->stateid,
+ &old_delegation->stateid) &&
+ delegation->type == old_delegation->type) {
+ goto out;
+ }
+ /*
+ * Deal with broken servers that hand out two
+ * delegations for the same file.
+ * Allow for upgrades to a WRITE delegation, but
+ * nothing else.
+ */
+ dfprintk(FILE, "%s: server %s handed out "
+ "a duplicate delegation!\n",
+ __func__, clp->cl_hostname);
+ if (delegation->type == old_delegation->type ||
+ !(delegation->type & FMODE_WRITE)) {
+ freeme = delegation;
+ delegation = NULL;
+ goto out;
+ }
+ freeme = nfs_detach_delegation_locked(nfsi, server);
+ }
+ list_add_rcu(&delegation->super_list, &server->delegations);
+ nfsi->delegation_state = delegation->type;
+ rcu_assign_pointer(nfsi->delegation, delegation);
+ delegation = NULL;
+
+ /* Ensure we revalidate the attributes and page cache! */
+ spin_lock(&inode->i_lock);
+ nfsi->cache_validity |= NFS_INO_REVAL_FORCED;
+ spin_unlock(&inode->i_lock);
+
+out:
+ spin_unlock(&clp->cl_lock);
+ if (delegation != NULL)
+ nfs_free_delegation(delegation);
+ if (freeme != NULL)
+ nfs_do_return_delegation(inode, freeme, 0);
+ return status;
+}
+
+/*
+ * Basic procedure for returning a delegation to the server
+ */
+static int __nfs_inode_return_delegation(struct inode *inode, struct nfs_delegation *delegation, int issync)
+{
+ struct nfs_inode *nfsi = NFS_I(inode);
+ int err;
+
+ /*
+ * Guard against new delegated open/lock/unlock calls and against
+ * state recovery
+ */
+ down_write(&nfsi->rwsem);
+ err = nfs_delegation_claim_opens(inode, &delegation->stateid);
+ up_write(&nfsi->rwsem);
+ if (err)
+ goto out;
+
+ err = nfs_do_return_delegation(inode, delegation, issync);
+out:
+ return err;
+}
+
+/**
+ * nfs_client_return_marked_delegations - return previously marked delegations
+ * @clp: nfs_client to process
+ *
+ * Returns zero on success, or a negative errno value.
+ */
+int nfs_client_return_marked_delegations(struct nfs_client *clp)
+{
+ struct nfs_delegation *delegation;
+ struct nfs_server *server;
+ struct inode *inode;
+ int err = 0;
+
+restart:
+ rcu_read_lock();
+ list_for_each_entry_rcu(server, &clp->cl_superblocks, client_link) {
+ list_for_each_entry_rcu(delegation, &server->delegations,
+ super_list) {
+ if (!test_and_clear_bit(NFS_DELEGATION_RETURN,
+ &delegation->flags))
+ continue;
+ inode = nfs_delegation_grab_inode(delegation);
+ if (inode == NULL)
+ continue;
+ delegation = nfs_detach_delegation(NFS_I(inode),
+ server);
+ rcu_read_unlock();
+
+ if (delegation != NULL) {
+ filemap_flush(inode->i_mapping);
+ err = __nfs_inode_return_delegation(inode,
+ delegation, 0);
+ }
+ iput(inode);
+ if (!err)
+ goto restart;
+ set_bit(NFS4CLNT_DELEGRETURN, &clp->cl_state);
+ return err;
+ }
+ }
+ rcu_read_unlock();
+ return 0;
+}
+
+/**
+ * nfs_inode_return_delegation_noreclaim - return delegation, don't reclaim opens
+ * @inode: inode to process
+ *
+ * Does not protect against delegation reclaims, therefore really only safe
+ * to be called from nfs4_clear_inode().
+ */
+void nfs_inode_return_delegation_noreclaim(struct inode *inode)
+{
+ struct nfs_server *server = NFS_SERVER(inode);
+ struct nfs_inode *nfsi = NFS_I(inode);
+ struct nfs_delegation *delegation;
+
+ if (rcu_access_pointer(nfsi->delegation) != NULL) {
+ delegation = nfs_detach_delegation(nfsi, server);
+ if (delegation != NULL)
+ nfs_do_return_delegation(inode, delegation, 0);
+ }
+}
+
+/**
+ * nfs_inode_return_delegation - synchronously return a delegation
+ * @inode: inode to process
+ *
+ * Returns zero on success, or a negative errno value.
+ */
+int nfs_inode_return_delegation(struct inode *inode)
+{
+ struct nfs_server *server = NFS_SERVER(inode);
+ struct nfs_inode *nfsi = NFS_I(inode);
+ struct nfs_delegation *delegation;
+ int err = 0;
+
+ if (rcu_access_pointer(nfsi->delegation) != NULL) {
+ delegation = nfs_detach_delegation(nfsi, server);
+ if (delegation != NULL) {
+ nfs_wb_all(inode);
+ err = __nfs_inode_return_delegation(inode, delegation, 1);
+ }
+ }
+ return err;
+}
+
+static void nfs_mark_return_delegation(struct nfs_server *server,
+ struct nfs_delegation *delegation)
+{
+ set_bit(NFS_DELEGATION_RETURN, &delegation->flags);
+ set_bit(NFS4CLNT_DELEGRETURN, &server->nfs_client->cl_state);
+}
+
+/**
+ * nfs_super_return_all_delegations - return delegations for one superblock
+ * @sb: sb to process
+ *
+ */
+void nfs_super_return_all_delegations(struct super_block *sb)
+{
+ struct nfs_server *server = NFS_SB(sb);
+ struct nfs_client *clp = server->nfs_client;
+ struct nfs_delegation *delegation;
+
+ if (clp == NULL)
+ return;
+
+ rcu_read_lock();
+ list_for_each_entry_rcu(delegation, &server->delegations, super_list) {
+ spin_lock(&delegation->lock);
+ set_bit(NFS_DELEGATION_RETURN, &delegation->flags);
+ spin_unlock(&delegation->lock);
+ }
+ rcu_read_unlock();
+
+ if (nfs_client_return_marked_delegations(clp) != 0)
+ nfs4_schedule_state_manager(clp);
+}
+
+static void nfs_mark_return_all_delegation_types(struct nfs_server *server,
+ fmode_t flags)
+{
+ struct nfs_delegation *delegation;
+
+ list_for_each_entry_rcu(delegation, &server->delegations, super_list) {
+ if ((delegation->type == (FMODE_READ|FMODE_WRITE)) && !(flags & FMODE_WRITE))
+ continue;
+ if (delegation->type & flags)
+ nfs_mark_return_delegation(server, delegation);
+ }
+}
+
+static void nfs_client_mark_return_all_delegation_types(struct nfs_client *clp,
+ fmode_t flags)
+{
+ struct nfs_server *server;
+
+ rcu_read_lock();
+ list_for_each_entry_rcu(server, &clp->cl_superblocks, client_link)
+ nfs_mark_return_all_delegation_types(server, flags);
+ rcu_read_unlock();
+}
+
+static void nfs_delegation_run_state_manager(struct nfs_client *clp)
+{
+ if (test_bit(NFS4CLNT_DELEGRETURN, &clp->cl_state))
+ nfs4_schedule_state_manager(clp);
+}
+
+void nfs_remove_bad_delegation(struct inode *inode)
+{
+ struct nfs_delegation *delegation;
+
+ delegation = nfs_detach_delegation(NFS_I(inode), NFS_SERVER(inode));
+ if (delegation) {
+ nfs_inode_find_state_and_recover(inode, &delegation->stateid);
+ nfs_free_delegation(delegation);
+ }
+}
+EXPORT_SYMBOL_GPL(nfs_remove_bad_delegation);
+
+/**
+ * nfs_expire_all_delegation_types
+ * @clp: client to process
+ * @flags: delegation types to expire
+ *
+ */
+void nfs_expire_all_delegation_types(struct nfs_client *clp, fmode_t flags)
+{
+ nfs_client_mark_return_all_delegation_types(clp, flags);
+ nfs_delegation_run_state_manager(clp);
+}
+
+/**
+ * nfs_expire_all_delegations
+ * @clp: client to process
+ *
+ */
+void nfs_expire_all_delegations(struct nfs_client *clp)
+{
+ nfs_expire_all_delegation_types(clp, FMODE_READ|FMODE_WRITE);
+}
+
+static void nfs_mark_return_unreferenced_delegations(struct nfs_server *server)
+{
+ struct nfs_delegation *delegation;
+
+ list_for_each_entry_rcu(delegation, &server->delegations, super_list) {
+ if (test_and_clear_bit(NFS_DELEGATION_REFERENCED, &delegation->flags))
+ continue;
+ nfs_mark_return_delegation(server, delegation);
+ }
+}
+
+/**
+ * nfs_expire_unreferenced_delegations - Eliminate unused delegations
+ * @clp: nfs_client to process
+ *
+ */
+void nfs_expire_unreferenced_delegations(struct nfs_client *clp)
+{
+ struct nfs_server *server;
+
+ rcu_read_lock();
+ list_for_each_entry_rcu(server, &clp->cl_superblocks, client_link)
+ nfs_mark_return_unreferenced_delegations(server);
+ rcu_read_unlock();
+
+ nfs_delegation_run_state_manager(clp);
+}
+
+/**
+ * nfs_async_inode_return_delegation - asynchronously return a delegation
+ * @inode: inode to process
+ * @stateid: state ID information
+ *
+ * Returns zero on success, or a negative errno value.
+ */
+int nfs_async_inode_return_delegation(struct inode *inode,
+ const nfs4_stateid *stateid)
+{
+ struct nfs_server *server = NFS_SERVER(inode);
+ struct nfs_client *clp = server->nfs_client;
+ struct nfs_delegation *delegation;
+
+ rcu_read_lock();
+ delegation = rcu_dereference(NFS_I(inode)->delegation);
+ if (delegation == NULL)
+ goto out_enoent;
+
+ if (!clp->cl_mvops->match_stateid(&delegation->stateid, stateid))
+ goto out_enoent;
+ nfs_mark_return_delegation(server, delegation);
+ rcu_read_unlock();
+
+ nfs_delegation_run_state_manager(clp);
+ return 0;
+out_enoent:
+ rcu_read_unlock();
+ return -ENOENT;
+}
+
+static struct inode *
+nfs_delegation_find_inode_server(struct nfs_server *server,
+ const struct nfs_fh *fhandle)
+{
+ struct nfs_delegation *delegation;
+ struct inode *res = NULL;
+
+ list_for_each_entry_rcu(delegation, &server->delegations, super_list) {
+ spin_lock(&delegation->lock);
+ if (delegation->inode != NULL &&
+ nfs_compare_fh(fhandle, &NFS_I(delegation->inode)->fh) == 0) {
+ res = igrab(delegation->inode);
+ }
+ spin_unlock(&delegation->lock);
+ if (res != NULL)
+ break;
+ }
+ return res;
+}
+
+/**
+ * nfs_delegation_find_inode - retrieve the inode associated with a delegation
+ * @clp: client state handle
+ * @fhandle: filehandle from a delegation recall
+ *
+ * Returns pointer to inode matching "fhandle," or NULL if a matching inode
+ * cannot be found.
+ */
+struct inode *nfs_delegation_find_inode(struct nfs_client *clp,
+ const struct nfs_fh *fhandle)
+{
+ struct nfs_server *server;
+ struct inode *res = NULL;
+
+ rcu_read_lock();
+ list_for_each_entry_rcu(server, &clp->cl_superblocks, client_link) {
+ res = nfs_delegation_find_inode_server(server, fhandle);
+ if (res != NULL)
+ break;
+ }
+ rcu_read_unlock();
+ return res;
+}
+
+static void nfs_delegation_mark_reclaim_server(struct nfs_server *server)
+{
+ struct nfs_delegation *delegation;
+
+ list_for_each_entry_rcu(delegation, &server->delegations, super_list)
+ set_bit(NFS_DELEGATION_NEED_RECLAIM, &delegation->flags);
+}
+
+/**
+ * nfs_delegation_mark_reclaim - mark all delegations as needing to be reclaimed
+ * @clp: nfs_client to process
+ *
+ */
+void nfs_delegation_mark_reclaim(struct nfs_client *clp)
+{
+ struct nfs_server *server;
+
+ rcu_read_lock();
+ list_for_each_entry_rcu(server, &clp->cl_superblocks, client_link)
+ nfs_delegation_mark_reclaim_server(server);
+ rcu_read_unlock();
+}
+
+/**
+ * nfs_delegation_reap_unclaimed - reap unclaimed delegations after reboot recovery is done
+ * @clp: nfs_client to process
+ *
+ */
+void nfs_delegation_reap_unclaimed(struct nfs_client *clp)
+{
+ struct nfs_delegation *delegation;
+ struct nfs_server *server;
+ struct inode *inode;
+
+restart:
+ rcu_read_lock();
+ list_for_each_entry_rcu(server, &clp->cl_superblocks, client_link) {
+ list_for_each_entry_rcu(delegation, &server->delegations,
+ super_list) {
+ if (test_bit(NFS_DELEGATION_NEED_RECLAIM,
+ &delegation->flags) == 0)
+ continue;
+ inode = nfs_delegation_grab_inode(delegation);
+ if (inode == NULL)
+ continue;
+ delegation = nfs_detach_delegation(NFS_I(inode),
+ server);
+ rcu_read_unlock();
+
+ if (delegation != NULL)
+ nfs_free_delegation(delegation);
+ iput(inode);
+ goto restart;
+ }
+ }
+ rcu_read_unlock();
+}
+
+/**
+ * nfs_delegations_present - check for existence of delegations
+ * @clp: client state handle
+ *
+ * Returns one if there are any nfs_delegation structures attached
+ * to this nfs_client.
+ */
+int nfs_delegations_present(struct nfs_client *clp)
+{
+ struct nfs_server *server;
+ int ret = 0;
+
+ rcu_read_lock();
+ list_for_each_entry_rcu(server, &clp->cl_superblocks, client_link)
+ if (!list_empty(&server->delegations)) {
+ ret = 1;
+ break;
+ }
+ rcu_read_unlock();
+ return ret;
+}
+
+/**
+ * nfs4_copy_delegation_stateid - Copy inode's state ID information
+ * @dst: stateid data structure to fill in
+ * @inode: inode to check
+ * @flags: delegation type requirement
+ *
+ * Returns "true" and fills in "dst->data" * if inode had a delegation,
+ * otherwise "false" is returned.
+ */
+bool nfs4_copy_delegation_stateid(nfs4_stateid *dst, struct inode *inode,
+ fmode_t flags)
+{
+ struct nfs_inode *nfsi = NFS_I(inode);
+ struct nfs_delegation *delegation;
+ bool ret;
+
+ flags &= FMODE_READ|FMODE_WRITE;
+ rcu_read_lock();
+ delegation = rcu_dereference(nfsi->delegation);
+ ret = (delegation != NULL && (delegation->type & flags) == flags);
+ if (ret) {
+ nfs4_stateid_copy(dst, &delegation->stateid);
+ nfs_mark_delegation_referenced(delegation);
+ }
+ rcu_read_unlock();
+ return ret;
+}