From: Dai Ngo dai.ngo@oracle.com
[ Upstream commit df24ac7a2e3a9d0bc68f1756a880e50bfe4b4522 ]
Currently nfsd4_setup_inter_ssc returns the vfsmount of the source server's export when the mount completes. After the copy is done nfsd4_cleanup_inter_ssc is called with the vfsmount of the source server and it searches nfsd_ssc_mount_list for a matching entry to do the clean up.
The problems with this approach are (1) the need to search the nfsd_ssc_mount_list and (2) the code has to handle the case where the matching entry is not found which looks ugly.
The enhancement is instead of nfsd4_setup_inter_ssc returning the vfsmount, it returns the nfsd4_ssc_umount_item which has the vfsmount embedded in it. When nfsd4_cleanup_inter_ssc is called it's passed with the nfsd4_ssc_umount_item directly to do the clean up so no searching is needed and there is no need to handle the 'not found' case.
Signed-off-by: Dai Ngo dai.ngo@oracle.com Signed-off-by: Chuck Lever chuck.lever@oracle.com [ cel: adjusted whitespace and variable/function names ] Reviewed-by: Olga Kornievskaia kolga@netapp.com Stable-dep-of: 34e8f9ec4c9a ("NFSD: fix leaked reference count of nfsd4_ssc_umount_item") Signed-off-by: Sasha Levin sashal@kernel.org --- fs/nfsd/nfs4proc.c | 111 ++++++++++++++++------------------------ fs/nfsd/xdr4.h | 2 +- include/linux/nfs_ssc.h | 2 +- 3 files changed, 46 insertions(+), 69 deletions(-)
diff --git a/fs/nfsd/nfs4proc.c b/fs/nfsd/nfs4proc.c index f189ba7995f5a..dbaf33398c827 100644 --- a/fs/nfsd/nfs4proc.c +++ b/fs/nfsd/nfs4proc.c @@ -1293,15 +1293,15 @@ extern void nfs_sb_deactive(struct super_block *sb); * setup a work entry in the ssc delayed unmount list. */ static __be32 nfsd4_ssc_setup_dul(struct nfsd_net *nn, char *ipaddr, - struct nfsd4_ssc_umount_item **retwork, struct vfsmount **ss_mnt) + struct nfsd4_ssc_umount_item **nsui) { struct nfsd4_ssc_umount_item *ni = NULL; struct nfsd4_ssc_umount_item *work = NULL; struct nfsd4_ssc_umount_item *tmp; DEFINE_WAIT(wait); + __be32 status = 0;
- *ss_mnt = NULL; - *retwork = NULL; + *nsui = NULL; work = kzalloc(sizeof(*work), GFP_KERNEL); try_again: spin_lock(&nn->nfsd_ssc_lock); @@ -1325,12 +1325,12 @@ static __be32 nfsd4_ssc_setup_dul(struct nfsd_net *nn, char *ipaddr, finish_wait(&nn->nfsd_ssc_waitq, &wait); goto try_again; } - *ss_mnt = ni->nsui_vfsmount; + *nsui = ni; refcount_inc(&ni->nsui_refcnt); spin_unlock(&nn->nfsd_ssc_lock); kfree(work);
- /* return vfsmount in ss_mnt */ + /* return vfsmount in (*nsui)->nsui_vfsmount */ return 0; } if (work) { @@ -1338,31 +1338,32 @@ static __be32 nfsd4_ssc_setup_dul(struct nfsd_net *nn, char *ipaddr, refcount_set(&work->nsui_refcnt, 2); work->nsui_busy = true; list_add_tail(&work->nsui_list, &nn->nfsd_ssc_mount_list); - *retwork = work; - } + *nsui = work; + } else + status = nfserr_resource; spin_unlock(&nn->nfsd_ssc_lock); - return 0; + return status; }
-static void nfsd4_ssc_update_dul_work(struct nfsd_net *nn, - struct nfsd4_ssc_umount_item *work, struct vfsmount *ss_mnt) +static void nfsd4_ssc_update_dul(struct nfsd_net *nn, + struct nfsd4_ssc_umount_item *nsui, + struct vfsmount *ss_mnt) { - /* set nsui_vfsmount, clear busy flag and wakeup waiters */ spin_lock(&nn->nfsd_ssc_lock); - work->nsui_vfsmount = ss_mnt; - work->nsui_busy = false; + nsui->nsui_vfsmount = ss_mnt; + nsui->nsui_busy = false; wake_up_all(&nn->nfsd_ssc_waitq); spin_unlock(&nn->nfsd_ssc_lock); }
-static void nfsd4_ssc_cancel_dul_work(struct nfsd_net *nn, - struct nfsd4_ssc_umount_item *work) +static void nfsd4_ssc_cancel_dul(struct nfsd_net *nn, + struct nfsd4_ssc_umount_item *nsui) { spin_lock(&nn->nfsd_ssc_lock); - list_del(&work->nsui_list); + list_del(&nsui->nsui_list); wake_up_all(&nn->nfsd_ssc_waitq); spin_unlock(&nn->nfsd_ssc_lock); - kfree(work); + kfree(nsui); }
/* @@ -1370,7 +1371,7 @@ static void nfsd4_ssc_cancel_dul_work(struct nfsd_net *nn, */ static __be32 nfsd4_interssc_connect(struct nl4_server *nss, struct svc_rqst *rqstp, - struct vfsmount **mount) + struct nfsd4_ssc_umount_item **nsui) { struct file_system_type *type; struct vfsmount *ss_mnt; @@ -1381,7 +1382,6 @@ nfsd4_interssc_connect(struct nl4_server *nss, struct svc_rqst *rqstp, char *ipaddr, *dev_name, *raw_data; int len, raw_len; __be32 status = nfserr_inval; - struct nfsd4_ssc_umount_item *work = NULL; struct nfsd_net *nn = net_generic(SVC_NET(rqstp), nfsd_net_id);
naddr = &nss->u.nl4_addr; @@ -1389,6 +1389,7 @@ nfsd4_interssc_connect(struct nl4_server *nss, struct svc_rqst *rqstp, naddr->addr_len, (struct sockaddr *)&tmp_addr, sizeof(tmp_addr)); + *nsui = NULL; if (tmp_addrlen == 0) goto out_err;
@@ -1431,10 +1432,10 @@ nfsd4_interssc_connect(struct nl4_server *nss, struct svc_rqst *rqstp, goto out_free_rawdata; snprintf(dev_name, len + 5, "%s%s%s:/", startsep, ipaddr, endsep);
- status = nfsd4_ssc_setup_dul(nn, ipaddr, &work, &ss_mnt); + status = nfsd4_ssc_setup_dul(nn, ipaddr, nsui); if (status) goto out_free_devname; - if (ss_mnt) + if ((*nsui)->nsui_vfsmount) goto out_done;
/* Use an 'internal' mount: SB_KERNMOUNT -> MNT_INTERNAL */ @@ -1442,15 +1443,12 @@ nfsd4_interssc_connect(struct nl4_server *nss, struct svc_rqst *rqstp, module_put(type->owner); if (IS_ERR(ss_mnt)) { status = nfserr_nodev; - if (work) - nfsd4_ssc_cancel_dul_work(nn, work); + nfsd4_ssc_cancel_dul(nn, *nsui); goto out_free_devname; } - if (work) - nfsd4_ssc_update_dul_work(nn, work, ss_mnt); + nfsd4_ssc_update_dul(nn, *nsui, ss_mnt); out_done: status = 0; - *mount = ss_mnt;
out_free_devname: kfree(dev_name); @@ -1474,7 +1472,7 @@ nfsd4_interssc_connect(struct nl4_server *nss, struct svc_rqst *rqstp, static __be32 nfsd4_setup_inter_ssc(struct svc_rqst *rqstp, struct nfsd4_compound_state *cstate, - struct nfsd4_copy *copy, struct vfsmount **mount) + struct nfsd4_copy *copy) { struct svc_fh *s_fh = NULL; stateid_t *s_stid = ©->cp_src_stateid; @@ -1487,7 +1485,7 @@ nfsd4_setup_inter_ssc(struct svc_rqst *rqstp, if (status) goto out;
- status = nfsd4_interssc_connect(copy->cp_src, rqstp, mount); + status = nfsd4_interssc_connect(copy->cp_src, rqstp, ©->ss_nsui); if (status) goto out;
@@ -1505,45 +1503,27 @@ nfsd4_setup_inter_ssc(struct svc_rqst *rqstp, }
static void -nfsd4_cleanup_inter_ssc(struct vfsmount *ss_mnt, struct file *filp, +nfsd4_cleanup_inter_ssc(struct nfsd4_ssc_umount_item *nsui, struct file *filp, struct nfsd_file *dst) { - bool found = false; - long timeout; - struct nfsd4_ssc_umount_item *tmp; - struct nfsd4_ssc_umount_item *ni = NULL; struct nfsd_net *nn = net_generic(dst->nf_net, nfsd_net_id); + long timeout = msecs_to_jiffies(nfsd4_ssc_umount_timeout);
nfs42_ssc_close(filp); nfsd_file_put(dst); fput(filp);
- if (!nn) { - mntput(ss_mnt); - return; - } spin_lock(&nn->nfsd_ssc_lock); - timeout = msecs_to_jiffies(nfsd4_ssc_umount_timeout); - list_for_each_entry_safe(ni, tmp, &nn->nfsd_ssc_mount_list, nsui_list) { - if (ni->nsui_vfsmount->mnt_sb == ss_mnt->mnt_sb) { - list_del(&ni->nsui_list); - /* - * vfsmount can be shared by multiple exports, - * decrement refcnt. If the count drops to 1 it - * will be unmounted when nsui_expire expires. - */ - refcount_dec(&ni->nsui_refcnt); - ni->nsui_expire = jiffies + timeout; - list_add_tail(&ni->nsui_list, &nn->nfsd_ssc_mount_list); - found = true; - break; - } - } + list_del(&nsui->nsui_list); + /* + * vfsmount can be shared by multiple exports, + * decrement refcnt. If the count drops to 1 it + * will be unmounted when nsui_expire expires. + */ + refcount_dec(&nsui->nsui_refcnt); + nsui->nsui_expire = jiffies + timeout; + list_add_tail(&nsui->nsui_list, &nn->nfsd_ssc_mount_list); spin_unlock(&nn->nfsd_ssc_lock); - if (!found) { - mntput(ss_mnt); - return; - } }
#else /* CONFIG_NFSD_V4_2_INTER_SSC */ @@ -1551,15 +1531,13 @@ nfsd4_cleanup_inter_ssc(struct vfsmount *ss_mnt, struct file *filp, static __be32 nfsd4_setup_inter_ssc(struct svc_rqst *rqstp, struct nfsd4_compound_state *cstate, - struct nfsd4_copy *copy, - struct vfsmount **mount) + struct nfsd4_copy *copy) { - *mount = NULL; return nfserr_inval; }
static void -nfsd4_cleanup_inter_ssc(struct vfsmount *ss_mnt, struct file *filp, +nfsd4_cleanup_inter_ssc(struct nfsd4_ssc_umount_item *nsui, struct file *filp, struct nfsd_file *dst) { } @@ -1700,7 +1678,7 @@ static void dup_copy_fields(struct nfsd4_copy *src, struct nfsd4_copy *dst) memcpy(dst->cp_src, src->cp_src, sizeof(struct nl4_server)); memcpy(&dst->stateid, &src->stateid, sizeof(src->stateid)); memcpy(&dst->c_fh, &src->c_fh, sizeof(src->c_fh)); - dst->ss_mnt = src->ss_mnt; + dst->ss_nsui = src->ss_nsui; }
static void cleanup_async_copy(struct nfsd4_copy *copy) @@ -1749,8 +1727,8 @@ static int nfsd4_do_async_copy(void *data) if (nfsd4_ssc_is_inter(copy)) { struct file *filp;
- filp = nfs42_ssc_open(copy->ss_mnt, ©->c_fh, - ©->stateid); + filp = nfs42_ssc_open(copy->ss_nsui->nsui_vfsmount, + ©->c_fh, ©->stateid); if (IS_ERR(filp)) { switch (PTR_ERR(filp)) { case -EBADF: @@ -1764,7 +1742,7 @@ static int nfsd4_do_async_copy(void *data) } nfserr = nfsd4_do_copy(copy, filp, copy->nf_dst->nf_file, false); - nfsd4_cleanup_inter_ssc(copy->ss_mnt, filp, copy->nf_dst); + nfsd4_cleanup_inter_ssc(copy->ss_nsui, filp, copy->nf_dst); } else { nfserr = nfsd4_do_copy(copy, copy->nf_src->nf_file, copy->nf_dst->nf_file, false); @@ -1790,8 +1768,7 @@ nfsd4_copy(struct svc_rqst *rqstp, struct nfsd4_compound_state *cstate, status = nfserr_notsupp; goto out; } - status = nfsd4_setup_inter_ssc(rqstp, cstate, copy, - ©->ss_mnt); + status = nfsd4_setup_inter_ssc(rqstp, cstate, copy); if (status) return nfserr_offload_denied; } else { diff --git a/fs/nfsd/xdr4.h b/fs/nfsd/xdr4.h index 4fd2cf6d1d2dc..510978e602da6 100644 --- a/fs/nfsd/xdr4.h +++ b/fs/nfsd/xdr4.h @@ -571,7 +571,7 @@ struct nfsd4_copy { struct task_struct *copy_task; refcount_t refcount;
- struct vfsmount *ss_mnt; + struct nfsd4_ssc_umount_item *ss_nsui; struct nfs_fh c_fh; nfs4_stateid stateid; }; diff --git a/include/linux/nfs_ssc.h b/include/linux/nfs_ssc.h index 75843c00f326a..22265b1ff0800 100644 --- a/include/linux/nfs_ssc.h +++ b/include/linux/nfs_ssc.h @@ -53,6 +53,7 @@ static inline void nfs42_ssc_close(struct file *filep) if (nfs_ssc_client_tbl.ssc_nfs4_ops) (*nfs_ssc_client_tbl.ssc_nfs4_ops->sco_close)(filep); } +#endif
struct nfsd4_ssc_umount_item { struct list_head nsui_list; @@ -66,7 +67,6 @@ struct nfsd4_ssc_umount_item { struct vfsmount *nsui_vfsmount; char nsui_ipaddr[RPC_MAX_ADDRBUFLEN + 1]; }; -#endif
/* * NFS_FS