From f044636d972246d451e06226cc1675d5da389762 Mon Sep 17 00:00:00 2001 From: Trond Myklebust Date: Thu, 26 Feb 2015 16:09:04 -0500 Subject: NFS: Add attribute update barriers to nfs_setattr_update_inode() Ensure that other operations which raced with our setattr RPC call cannot revert the file attribute changes that were made on the server. To do so, we artificially bump the attribute generation counter on the inode so that all calls to nfs_fattr_init() that precede ours will be dropped. The motivation for the patch came from Chuck Lever's reports of readaheads racing with truncate operations and causing the file size to be reverted. Reported-by: Chuck Lever Signed-off-by: Trond Myklebust Tested-by: Chuck Lever --- fs/nfs/inode.c | 17 ++++++++++++----- fs/nfs/nfs3proc.c | 2 +- fs/nfs/nfs4proc.c | 6 +++--- fs/nfs/proc.c | 2 +- 4 files changed, 17 insertions(+), 10 deletions(-) (limited to 'fs/nfs') diff --git a/fs/nfs/inode.c b/fs/nfs/inode.c index b0cbc1ba82d..3a2d127de49 100644 --- a/fs/nfs/inode.c +++ b/fs/nfs/inode.c @@ -556,6 +556,7 @@ EXPORT_SYMBOL_GPL(nfs_setattr); * This is a copy of the common vmtruncate, but with the locking * corrected to take into account the fact that NFS requires * inode->i_size to be updated under the inode->i_lock. + * Note: must be called with inode->i_lock held! */ static int nfs_vmtruncate(struct inode * inode, loff_t offset) { @@ -565,14 +566,14 @@ static int nfs_vmtruncate(struct inode * inode, loff_t offset) if (err) goto out; - spin_lock(&inode->i_lock); i_size_write(inode, offset); /* Optimisation */ if (offset == 0) NFS_I(inode)->cache_validity &= ~NFS_INO_INVALID_DATA; - spin_unlock(&inode->i_lock); + spin_unlock(&inode->i_lock); truncate_pagecache(inode, offset); + spin_lock(&inode->i_lock); out: return err; } @@ -585,10 +586,15 @@ out: * Note: we do this in the *proc.c in order to ensure that * it works for things like exclusive creates too. */ -void nfs_setattr_update_inode(struct inode *inode, struct iattr *attr) +void nfs_setattr_update_inode(struct inode *inode, struct iattr *attr, + struct nfs_fattr *fattr) { + /* Barrier: bump the attribute generation count. */ + nfs_fattr_set_barrier(fattr); + + spin_lock(&inode->i_lock); + NFS_I(inode)->attr_gencount = fattr->gencount; if ((attr->ia_valid & (ATTR_MODE|ATTR_UID|ATTR_GID)) != 0) { - spin_lock(&inode->i_lock); if ((attr->ia_valid & ATTR_MODE) != 0) { int mode = attr->ia_mode & S_IALLUGO; mode |= inode->i_mode & ~S_IALLUGO; @@ -600,12 +606,13 @@ void nfs_setattr_update_inode(struct inode *inode, struct iattr *attr) inode->i_gid = attr->ia_gid; nfs_set_cache_invalid(inode, NFS_INO_INVALID_ACCESS | NFS_INO_INVALID_ACL); - spin_unlock(&inode->i_lock); } if ((attr->ia_valid & ATTR_SIZE) != 0) { nfs_inc_stats(inode, NFSIOS_SETATTRTRUNC); nfs_vmtruncate(inode, attr->ia_size); } + nfs_update_inode(inode, fattr); + spin_unlock(&inode->i_lock); } EXPORT_SYMBOL_GPL(nfs_setattr_update_inode); diff --git a/fs/nfs/nfs3proc.c b/fs/nfs/nfs3proc.c index 78e557c3ab8..11109a137c0 100644 --- a/fs/nfs/nfs3proc.c +++ b/fs/nfs/nfs3proc.c @@ -138,7 +138,7 @@ nfs3_proc_setattr(struct dentry *dentry, struct nfs_fattr *fattr, nfs_fattr_init(fattr); status = rpc_call_sync(NFS_CLIENT(inode), &msg, 0); if (status == 0) - nfs_setattr_update_inode(inode, sattr); + nfs_setattr_update_inode(inode, sattr, fattr); dprintk("NFS reply setattr: %d\n", status); return status; } diff --git a/fs/nfs/nfs4proc.c b/fs/nfs/nfs4proc.c index 4e41340e957..c499e02a58c 100644 --- a/fs/nfs/nfs4proc.c +++ b/fs/nfs/nfs4proc.c @@ -2416,8 +2416,8 @@ static int _nfs4_do_open(struct inode *dir, opendata->o_res.f_attr, sattr, state, label, olabel); if (status == 0) { - nfs_setattr_update_inode(state->inode, sattr); - nfs_post_op_update_inode(state->inode, opendata->o_res.f_attr); + nfs_setattr_update_inode(state->inode, sattr, + opendata->o_res.f_attr); nfs_setsecurity(state->inode, opendata->o_res.f_attr, olabel); } } @@ -3291,7 +3291,7 @@ nfs4_proc_setattr(struct dentry *dentry, struct nfs_fattr *fattr, status = nfs4_do_setattr(inode, cred, fattr, sattr, state, NULL, label); if (status == 0) { - nfs_setattr_update_inode(inode, sattr); + nfs_setattr_update_inode(inode, sattr, fattr); nfs_setsecurity(inode, fattr, label); } nfs4_label_free(label); diff --git a/fs/nfs/proc.c b/fs/nfs/proc.c index b09cc23d6f4..6202bc0f11b 100644 --- a/fs/nfs/proc.c +++ b/fs/nfs/proc.c @@ -139,7 +139,7 @@ nfs_proc_setattr(struct dentry *dentry, struct nfs_fattr *fattr, nfs_fattr_init(fattr); status = rpc_call_sync(NFS_CLIENT(inode), &msg, 0); if (status == 0) - nfs_setattr_update_inode(inode, sattr); + nfs_setattr_update_inode(inode, sattr, fattr); dprintk("NFS reply setattr: %d\n", status); return status; } -- cgit v1.2.3-70-g09d2