2020-11-04 16:28:50

by Trond Myklebust

[permalink] [raw]
Subject: [PATCH v3 14/17] NFS: Allow the NFS generic code to pass in a verifier to readdir

From: Trond Myklebust <[email protected]>

If we're ever going to allow support for servers that use the readdir
verifier, then that use needs to be managed by the middle layers as
those need to be able to reject cookies from other verifiers.

Signed-off-by: Trond Myklebust <[email protected]>
---
fs/nfs/dir.c | 23 ++++++++++++++++++-----
fs/nfs/nfs3proc.c | 35 +++++++++++++++++------------------
fs/nfs/nfs4proc.c | 38 ++++++++++++++++++--------------------
fs/nfs/proc.c | 18 +++++++++---------
include/linux/nfs_xdr.h | 17 +++++++++++++++--
5 files changed, 77 insertions(+), 54 deletions(-)

diff --git a/fs/nfs/dir.c b/fs/nfs/dir.c
index b226f6f3ae96..3ee0668a9719 100644
--- a/fs/nfs/dir.c
+++ b/fs/nfs/dir.c
@@ -469,8 +469,20 @@ static int nfs_readdir_xdr_filler(struct nfs_readdir_descriptor *desc,
u64 cookie, struct page **pages,
size_t bufsize)
{
- struct file *file = desc->file;
- struct inode *inode = file_inode(file);
+ struct inode *inode = file_inode(desc->file);
+ __be32 verf_res[2];
+ struct nfs_readdir_arg arg = {
+ .dentry = file_dentry(desc->file),
+ .cred = desc->file->f_cred,
+ .verf = NFS_I(inode)->cookieverf,
+ .cookie = cookie,
+ .pages = pages,
+ .page_len = bufsize,
+ .plus = desc->plus,
+ };
+ struct nfs_readdir_res res = {
+ .verf = verf_res,
+ };
unsigned long timestamp, gencount;
int error;

@@ -478,20 +490,21 @@ static int nfs_readdir_xdr_filler(struct nfs_readdir_descriptor *desc,
timestamp = jiffies;
gencount = nfs_inc_attr_generation_counter();
desc->dir_verifier = nfs_save_change_attribute(inode);
- error = NFS_PROTO(inode)->readdir(file_dentry(file), file->f_cred,
- cookie, pages, bufsize, desc->plus);
+ error = NFS_PROTO(inode)->readdir(&arg, &res);
if (error < 0) {
/* We requested READDIRPLUS, but the server doesn't grok it */
if (error == -ENOTSUPP && desc->plus) {
NFS_SERVER(inode)->caps &= ~NFS_CAP_READDIRPLUS;
clear_bit(NFS_INO_ADVISE_RDPLUS, &NFS_I(inode)->flags);
- desc->plus = false;
+ desc->plus = arg.plus = false;
goto again;
}
goto error;
}
desc->timestamp = timestamp;
desc->gencount = gencount;
+ memcpy(NFS_I(inode)->cookieverf, res.verf,
+ sizeof(NFS_I(inode)->cookieverf));
error:
return error;
}
diff --git a/fs/nfs/nfs3proc.c b/fs/nfs/nfs3proc.c
index 6b66b73a50eb..5c4e23abc345 100644
--- a/fs/nfs/nfs3proc.c
+++ b/fs/nfs/nfs3proc.c
@@ -662,37 +662,36 @@ nfs3_proc_rmdir(struct inode *dir, const struct qstr *name)
* Also note that this implementation handles both plain readdir and
* readdirplus.
*/
-static int
-nfs3_proc_readdir(struct dentry *dentry, const struct cred *cred,
- u64 cookie, struct page **pages, unsigned int count, bool plus)
+static int nfs3_proc_readdir(struct nfs_readdir_arg *nr_arg,
+ struct nfs_readdir_res *nr_res)
{
- struct inode *dir = d_inode(dentry);
- __be32 *verf = NFS_I(dir)->cookieverf;
+ struct inode *dir = d_inode(nr_arg->dentry);
struct nfs3_readdirargs arg = {
.fh = NFS_FH(dir),
- .cookie = cookie,
- .verf = {verf[0], verf[1]},
- .plus = plus,
- .count = count,
- .pages = pages
+ .cookie = nr_arg->cookie,
+ .plus = nr_arg->plus,
+ .count = nr_arg->page_len,
+ .pages = nr_arg->pages
};
struct nfs3_readdirres res = {
- .verf = verf,
- .plus = plus
+ .verf = nr_res->verf,
+ .plus = nr_arg->plus,
};
struct rpc_message msg = {
.rpc_proc = &nfs3_procedures[NFS3PROC_READDIR],
.rpc_argp = &arg,
.rpc_resp = &res,
- .rpc_cred = cred,
+ .rpc_cred = nr_arg->cred,
};
int status = -ENOMEM;

- if (plus)
+ if (nr_arg->plus)
msg.rpc_proc = &nfs3_procedures[NFS3PROC_READDIRPLUS];
+ if (arg.cookie)
+ memcpy(arg.verf, nr_arg->verf, sizeof(arg.verf));

- dprintk("NFS call readdir%s %d\n",
- plus? "plus" : "", (unsigned int) cookie);
+ dprintk("NFS call readdir%s %llu\n", nr_arg->plus ? "plus" : "",
+ (unsigned long long)nr_arg->cookie);

res.dir_attr = nfs_alloc_fattr();
if (res.dir_attr == NULL)
@@ -705,8 +704,8 @@ nfs3_proc_readdir(struct dentry *dentry, const struct cred *cred,

nfs_free_fattr(res.dir_attr);
out:
- dprintk("NFS reply readdir%s: %d\n",
- plus? "plus" : "", status);
+ dprintk("NFS reply readdir%s: %d\n", nr_arg->plus ? "plus" : "",
+ status);
return status;
}

diff --git a/fs/nfs/nfs4proc.c b/fs/nfs/nfs4proc.c
index a5b9356bee6a..8e82f988a11f 100644
--- a/fs/nfs/nfs4proc.c
+++ b/fs/nfs/nfs4proc.c
@@ -4961,35 +4961,34 @@ static int nfs4_proc_mkdir(struct inode *dir, struct dentry *dentry,
return err;
}

-static int _nfs4_proc_readdir(struct dentry *dentry, const struct cred *cred,
- u64 cookie, struct page **pages, unsigned int count, bool plus)
+static int _nfs4_proc_readdir(struct nfs_readdir_arg *nr_arg,
+ struct nfs_readdir_res *nr_res)
{
- struct inode *dir = d_inode(dentry);
+ struct inode *dir = d_inode(nr_arg->dentry);
struct nfs4_readdir_arg args = {
.fh = NFS_FH(dir),
- .pages = pages,
+ .pages = nr_arg->pages,
.pgbase = 0,
- .count = count,
- .bitmask = NFS_SERVER(d_inode(dentry))->attr_bitmask,
- .plus = plus,
+ .count = nr_arg->page_len,
+ .bitmask = NFS_SERVER(d_inode(nr_arg->dentry))->attr_bitmask,
+ .plus = nr_arg->plus,
};
struct nfs4_readdir_res res;
struct rpc_message msg = {
.rpc_proc = &nfs4_procedures[NFSPROC4_CLNT_READDIR],
.rpc_argp = &args,
.rpc_resp = &res,
- .rpc_cred = cred,
+ .rpc_cred = nr_arg->cred,
};
int status;

- dprintk("%s: dentry = %pd2, cookie = %Lu\n", __func__,
- dentry,
- (unsigned long long)cookie);
- nfs4_setup_readdir(cookie, NFS_I(dir)->cookieverf, dentry, &args);
+ dprintk("%s: dentry = %pd2, cookie = %llu\n", __func__,
+ nr_arg->dentry, (unsigned long long)nr_arg->cookie);
+ nfs4_setup_readdir(nr_arg->cookie, nr_arg->verf, nr_arg->dentry, &args);
res.pgbase = args.pgbase;
status = nfs4_call_sync(NFS_SERVER(dir)->client, NFS_SERVER(dir), &msg, &args.seq_args, &res.seq_res, 0);
if (status >= 0) {
- memcpy(NFS_I(dir)->cookieverf, res.verifier.data, NFS4_VERIFIER_SIZE);
+ memcpy(nr_res->verf, res.verifier.data, NFS4_VERIFIER_SIZE);
status += args.pgbase;
}

@@ -4999,19 +4998,18 @@ static int _nfs4_proc_readdir(struct dentry *dentry, const struct cred *cred,
return status;
}

-static int nfs4_proc_readdir(struct dentry *dentry, const struct cred *cred,
- u64 cookie, struct page **pages, unsigned int count, bool plus)
+static int nfs4_proc_readdir(struct nfs_readdir_arg *arg,
+ struct nfs_readdir_res *res)
{
struct nfs4_exception exception = {
.interruptible = true,
};
int err;
do {
- err = _nfs4_proc_readdir(dentry, cred, cookie,
- pages, count, plus);
- trace_nfs4_readdir(d_inode(dentry), err);
- err = nfs4_handle_exception(NFS_SERVER(d_inode(dentry)), err,
- &exception);
+ err = _nfs4_proc_readdir(arg, res);
+ trace_nfs4_readdir(d_inode(arg->dentry), err);
+ err = nfs4_handle_exception(NFS_SERVER(d_inode(arg->dentry)),
+ err, &exception);
} while (exception.retry);
return err;
}
diff --git a/fs/nfs/proc.c b/fs/nfs/proc.c
index 15c865cc837f..73ab7c59d3a7 100644
--- a/fs/nfs/proc.c
+++ b/fs/nfs/proc.c
@@ -499,26 +499,26 @@ nfs_proc_rmdir(struct inode *dir, const struct qstr *name)
* sure it is syntactically correct; the entries itself are decoded
* from nfs_readdir by calling the decode_entry function directly.
*/
-static int
-nfs_proc_readdir(struct dentry *dentry, const struct cred *cred,
- u64 cookie, struct page **pages, unsigned int count, bool plus)
+static int nfs_proc_readdir(struct nfs_readdir_arg *nr_arg,
+ struct nfs_readdir_res *nr_res)
{
- struct inode *dir = d_inode(dentry);
+ struct inode *dir = d_inode(nr_arg->dentry);
struct nfs_readdirargs arg = {
.fh = NFS_FH(dir),
- .cookie = cookie,
- .count = count,
- .pages = pages,
+ .cookie = nr_arg->cookie,
+ .count = nr_arg->page_len,
+ .pages = nr_arg->pages,
};
struct rpc_message msg = {
.rpc_proc = &nfs_procedures[NFSPROC_READDIR],
.rpc_argp = &arg,
- .rpc_cred = cred,
+ .rpc_cred = nr_arg->cred,
};
int status;

- dprintk("NFS call readdir %d\n", (unsigned int)cookie);
+ dprintk("NFS call readdir %llu\n", (unsigned long long)nr_arg->cookie);
status = rpc_call_sync(NFS_CLIENT(dir), &msg, 0);
+ nr_res->verf[0] = nr_res->verf[1] = 0;

nfs_invalidate_atime(dir);

diff --git a/include/linux/nfs_xdr.h b/include/linux/nfs_xdr.h
index d63cb862d58e..3327239fa2f9 100644
--- a/include/linux/nfs_xdr.h
+++ b/include/linux/nfs_xdr.h
@@ -750,6 +750,20 @@ struct nfs_entry {
struct nfs_server * server;
};

+struct nfs_readdir_arg {
+ struct dentry *dentry;
+ const struct cred *cred;
+ __be32 *verf;
+ u64 cookie;
+ struct page **pages;
+ unsigned int page_len;
+ bool plus;
+};
+
+struct nfs_readdir_res {
+ __be32 *verf;
+};
+
/*
* The following types are for NFSv2 only.
*/
@@ -1744,8 +1758,7 @@ struct nfs_rpc_ops {
unsigned int, struct iattr *);
int (*mkdir) (struct inode *, struct dentry *, struct iattr *);
int (*rmdir) (struct inode *, const struct qstr *);
- int (*readdir) (struct dentry *, const struct cred *,
- u64, struct page **, unsigned int, bool);
+ int (*readdir) (struct nfs_readdir_arg *, struct nfs_readdir_res *);
int (*mknod) (struct inode *, struct dentry *, struct iattr *,
dev_t);
int (*statfs) (struct nfs_server *, struct nfs_fh *,
--
2.28.0


2020-11-04 16:29:56

by Trond Myklebust

[permalink] [raw]
Subject: [PATCH v3 15/17] NFS: Handle NFS4ERR_NOT_SAME and NFSERR_BADCOOKIE from readdir calls

From: Trond Myklebust <[email protected]>

If the server returns NFS4ERR_NOT_SAME or tells us that the cookie is
bad in response to a READDIR call, then we should empty the page cache
so that we can fill it from scratch again.

Signed-off-by: Trond Myklebust <[email protected]>
---
fs/nfs/dir.c | 24 ++++++++++++++++--------
fs/nfs/nfs4proc.c | 2 ++
2 files changed, 18 insertions(+), 8 deletions(-)

diff --git a/fs/nfs/dir.c b/fs/nfs/dir.c
index 3ee0668a9719..3b44bef3a1b4 100644
--- a/fs/nfs/dir.c
+++ b/fs/nfs/dir.c
@@ -861,15 +861,21 @@ static int find_and_lock_cache_page(struct nfs_readdir_descriptor *desc)
return -ENOMEM;
if (nfs_readdir_page_needs_filling(desc->page)) {
res = nfs_readdir_xdr_to_array(desc, desc->page, inode);
- if (res < 0)
- goto error;
+ if (res < 0) {
+ nfs_readdir_page_unlock_and_put_cached(desc);
+ if (res == -EBADCOOKIE || res == -ENOTSYNC) {
+ invalidate_inode_pages2(desc->file->f_mapping);
+ desc->page_index = 0;
+ return -EAGAIN;
+ }
+ return res;
+ }
}
res = nfs_readdir_search_array(desc);
if (res == 0) {
nfsi->page_index = desc->page_index;
return 0;
}
-error:
nfs_readdir_page_unlock_and_put_cached(desc);
return res;
}
@@ -879,12 +885,12 @@ static int readdir_search_pagecache(struct nfs_readdir_descriptor *desc)
{
int res;

- if (desc->page_index == 0) {
- desc->current_index = 0;
- desc->prev_index = 0;
- desc->last_cookie = 0;
- }
do {
+ if (desc->page_index == 0) {
+ desc->current_index = 0;
+ desc->prev_index = 0;
+ desc->last_cookie = 0;
+ }
res = find_and_lock_cache_page(desc);
} while (res == -EAGAIN);
return res;
@@ -1030,6 +1036,8 @@ static int nfs_readdir(struct file *file, struct dir_context *ctx)
res = uncached_readdir(desc);
if (res == 0)
continue;
+ if (res == -EBADCOOKIE || res == -ENOTSYNC)
+ res = 0;
}
break;
}
diff --git a/fs/nfs/nfs4proc.c b/fs/nfs/nfs4proc.c
index 8e82f988a11f..3f1fdb06ba56 100644
--- a/fs/nfs/nfs4proc.c
+++ b/fs/nfs/nfs4proc.c
@@ -184,6 +184,8 @@ static int nfs4_map_errors(int err)
return -EPROTONOSUPPORT;
case -NFS4ERR_FILE_OPEN:
return -EBUSY;
+ case -NFS4ERR_NOT_SAME:
+ return -ENOTSYNC;
default:
dprintk("%s could not handle NFSv4 error %d\n",
__func__, -err);
--
2.28.0