// SPDX-License-Identifier: GPL-2.0
/*
* linux/fs/nfs/file.c
*
* Copyright (C) 1992 Rick Sladkey
*/
#include <linux/fs.h>
#include <linux/file.h>
#include <linux/falloc.h>
#include <linux/mount.h>
#include <linux/nfs_fs.h>
#include <linux/nfs_ssc.h>
#include <linux/splice.h>
#include "delegation.h"
#include "internal.h"
#include "iostat.h"
#include "fscache.h"
#include "pnfs.h"
#include "nfstrace.h"
#ifdef CONFIG_NFS_V4_2
#include "nfs42.h"
#endif
#define NFSDBG_FACILITY NFSDBG_FILE
static int
nfs4_file_open(struct inode *inode, struct file *filp)
{
struct nfs_open_context *ctx;
struct dentry *dentry = file_dentry(filp);
struct dentry *parent = NULL;
struct inode *dir;
unsigned openflags = filp->f_flags;
struct iattr attr;
int err;
/*
* If no cached dentry exists or if it's negative, NFSv4 handled the
* opens in ->lookup() or ->create().
*
* We only get this far for a cached positive dentry. We skipped
* revalidation, so handle it here by dropping the dentry and returning
* -EOPENSTALE. The VFS will retry the lookup/create/open.
*/
dprintk("NFS: open file(%pd2)\n", dentry);
err = nfs_check_flags(openflags);
if (err)
return err;
/* We can't create new files here */
openflags &= ~(O_CREAT|O_EXCL);
parent = dget_parent(dentry);
dir = d_inode(parent);
ctx = alloc_nfs_open_context(file_dentry(filp),
flags_to_mode(openflags), filp);
err = PTR_ERR(ctx);
if (IS_ERR(ctx))
goto out;
attr.ia_valid = ATTR_OPEN;
if (openflags & O_TRUNC) {
attr.ia_valid |= ATTR_SIZE;
attr.ia_size = 0;
filemap_write_and_wait(inode->i_mapping);
}
inode = NFS_PROTO(dir)->open_context(dir, ctx, openflags, &attr, NULL);
if (IS_ERR(inode)) {
err = PTR_ERR(inode);
switch (err) {
default:
goto out_put_ctx;
case -ENOENT:
case -ESTALE:
case -EISDIR:
case -ENOTDIR:
case -ELOOP:
goto out_drop;
}
}
if (inode != d_inode(dentry))
goto out_drop;
nfs_file_set_open_context(filp, ctx);
nfs_fscache_open_file(inode, filp);
err = 0;
filp->f_mode |= FMODE_CAN_ODIRECT;
out_put_ctx:
put_nfs_open_context(ctx);
out:
dput(parent);
return err;
out_drop:
d_drop(dentry);
err = -EOPENSTALE;
goto out_put_ctx;
}
/*
* Flush all dirty pages, and check for write errors.
*/
static int
nfs4_file_flush(struct file *file, fl_owner_t id)
{
struct inode *inode = file_inode(file);
errseq_t since;
dprintk("NFS: flush(%pD2)\n", file);
nfs_inc_stats(inode, NFSIOS_VFSFLUSH);
if ((file->f_mode & FMODE_WRITE) == 0)
return 0;
/*
* If we're holding a write delegation, then check if we're required
* to flush the i/o on close. If not, then just start the i/o now.
*/
if (!nfs4_delegation_flush_on_close(inode))
return filemap_fdatawrite(file->f_mapping);
/* Flush writes to the server and return any errors */
since = filemap_sample_wb_err(file->f_mapping);
nfs_wb_all(inode);
return filemap_check_wb_err(file->f_mapping, since);
}
#ifdef CONFIG_NFS_V4_2
static ssize_t __nfs4_copy_file_range(struct file *file_in, loff_t pos_in,
struct file *file_out, loff_t pos_out,
size_t count, unsigned int flags)
{
struct nfs42_copy_notify_res *cn_resp = NULL;
struct nl4_server *nss = NULL;
nfs4_stateid *cnrs = NULL;
ssize_t ret;
bool sync = false;
/* Only offload copy if superblock is the same */
if (file_in->f_op != &nfs4_file_operations)
return -EXDEV;
if (!nfs_server_capable(file_inode(file_out), NFS_CAP_COPY) ||
!nfs_server_capable(file_inode(file_in), NFS_CAP_COPY))
return -EOPNOTSUPP;
if (file_inode(file_in) == file_inode(file_out))
return -EOPNOTSUPP;
/* if the copy size if smaller than 2 RPC payloads, make it
* synchronous
*/
if (count <= 2 * NFS_SERVER(file_inode(file_in))->rsize)
sync = true;
retry:
if (!nfs42_files_from_same_server(file_in, file_out)) {
/*
* for inter copy, if copy size is too small
* then fallback to generic copy.
*/
if (sync)
return -EOPNOTSUPP;
cn_resp = kzalloc(sizeof(struct nfs42_copy_notify_res),
GFP_KERNEL);
if (unlikely(cn_resp == NULL))
return -ENOMEM;
ret = nfs42_proc_copy_notify(file_in, file_out, cn_resp);
if (ret) {
ret = -EOPNOTSUPP;
goto out;
}
nss = &cn_resp->cnr_src;
cnrs = &cn_resp->cnr_stateid;
}
ret = nfs42_proc_copy(file_in, pos_in, file_out, pos_out, count,
nss, cnrs, sync);
out:
kfree(cn_resp);
if (ret == -EAGAIN)
goto retry;
return ret;
}
static ssize_t nfs4_copy_file_range(struct file *file_in, loff_t pos_in,
struct file *file_out, loff_t pos_out,
size_t count, unsigned int flags)
{
ssize_t ret;
ret = __nfs4_copy_file_range(file_in, pos_in, file_out, pos_out, count,
flags);
if (ret == -EOPNOTSUPP || ret == -EXDEV)
ret = splice_copy_file_range(file_in, pos_in, file_out,
pos_out, count);
return ret;
}
static loff_t nfs4_file_llseek(struct file *filep, loff_t offset, int whence)
{
loff_t ret;
switch (whence) {
case SEEK_HOLE:
case SEEK_DATA:
ret = nfs42_proc_llseek(filep, offset, whence);
if (ret != -EOPNOTSUPP)
return ret;
fallthrough;
default:
return nfs_file_llseek(filep, offset, whence);
}
}
static long nfs42_fallocate(struct file *filep, int mode, loff_t offset, loff_t len)
{
struct inode *inode = file_inode(filep);
long ret;
if (!S_ISREG(inode->i_mode))
return -EOPNOTSUPP;
if ((mode != 0) && (mode != (FALLOC_FL_PUNCH_HOLE | FALLOC_FL_KEEP_SIZE)))
return -EOPNOTSUPP;
ret = inode_newsize_ok(inode, offset + len);
if (ret < 0)
return ret;
if (mode & FALLOC_FL_PUNCH_HOLE)
return nfs42_proc_deallocate(filep, offset, len);
return nfs42_proc_allocate(filep, offset, len);
}
static loff_t nfs42_remap_file_range(struct file *src_file, loff_t src_off,
struct file *dst_file, loff_t dst_off, loff_t count,
unsigned int remap_flags)
{
struct inode *dst_inode = file_inode(dst_file);
struct nfs_server *server = NFS_SERVER(dst_inode);
struct inode *src_inode = file_inode(src_file);
unsigned int bs = server->clone_blksize;
bool same_inode = false;
int ret;
/* NFS does not support deduplication. */
if (remap_flags & REMAP_FILE_DEDUP)
return -EOPNOTSUPP;
if (remap_flags & ~REMAP_FILE_ADVISORY)
return -EINVAL;
if (IS_SWAPFILE(dst_inode) || IS_SWAPFILE(src_inode))
return -ETXTBSY;
/* check alignment w.r.t. clone_blksize */
ret = -EINVAL;
if (bs) {
if (!IS_ALIGNED(src_off, bs) || !IS_ALIGNED(dst_off, bs))
goto out;
if (!IS_ALIGNED(count, bs) && i_size_read(src_inode) != (src_off + count))
goto out;
}
if (src_inode == dst_inode)
same_inode = true;
/* XXX: do we lock at all? what if server needs CB_RECALL_LAYOUT? */
if (same_inode) {
inode_lock(src_inode);
} else if (dst_inode < src_inode) {
inode_lock_nested(dst_inode, I_MUTEX_PARENT);
inode_lock_nested(src_inode, I_MUTEX_CHILD);
} else {
inode_lock_nested(src_inode, I_MUTEX_PARENT);
inode_lock_nested(dst_inode, I_MUTEX_CHILD);
}
/* flush all pending writes on both src and dst so that server
* has the latest data */
ret = nfs_sync_inode(src_inode);
if (ret)
goto out_unlock;
ret = nfs_sync_inode(dst_inode);
if (ret)
goto out_unlock;
ret = nfs42_proc_clone(src_file, dst_file, src_off, dst_off, count);
/* truncate inode page cache of the dst range so that future reads can fetch
* new data from server */
if (!ret)
truncate_inode_pages_range(&dst_inode->i_data, dst_off, dst_off + count - 1);
out_unlock:
if (same_inode) {
inode_unlock(src_inode);
} else if (dst_inode < src_inode) {
inode_unlock(src_inode);
inode_unlock(dst_inode);
} else {
inode_unlock(dst_inode);
inode_unlock(src_inode);
}
out:
return ret < 0 ? ret : count;
}
static int read_name_gen = 1;
#define SSC_READ_NAME_BODY "ssc_read_%d"
static struct file *__nfs42_ssc_open(struct vfsmount *ss_mnt,
struct nfs_fh *src_fh, nfs4_stateid *stateid)
{
struct nfs_fattr *fattr = nfs_alloc_fattr();
struct file *filep, *res;
struct nfs_server *server;
struct inode *r_ino = NULL;
struct nfs_open_context *ctx;
struct nfs4_state_owner *sp;
char *read_name = NULL;
int len, status = 0;
server = NFS_SB(ss_mnt->mnt_sb);
if (!fattr)
return ERR_PTR(-ENOMEM);
status = nfs4_proc_getattr(server, src_fh, fattr, NULL);
if (status < 0) {
res = ERR_PTR(status);
goto out;
}
if (!S_ISREG(fattr->mode)) {
res = ERR_PTR(-EBADF);
goto out;
}
res = ERR_PTR(-ENOMEM);
len = strlen(SSC_READ_NAME_BODY) + 16;
read_name = kzalloc(len, GFP_KERNEL);
if (read_name == NULL)
goto out;
snprintf(read_name, len, SSC_READ_NAME_BODY, read_name_gen++);
r_ino = nfs_fhget(ss_mnt->mnt_sb, src_fh, fattr);
if (IS_ERR(r_ino)) {
res = ERR_CAST(r_ino);
goto out_free_name;
}
filep = alloc_file_pseudo(r_ino, ss_mnt, read_name, O_RDONLY,
r_ino->i_fop);
if (IS_ERR(filep)) {
res = ERR_CAST(filep);
iput(r_ino);
goto out_free_name;
}
ctx = alloc_nfs_open_context(filep->f_path.dentry,
flags_to_mode(filep->f_flags), filep);
if (IS_ERR(ctx)) {
res = ERR_CAST(ctx);
goto out_filep;
}
res = ERR_PTR(-EINVAL);
sp = nfs4_get_state_owner(server, ctx->cred, GFP_KERNEL);
if (sp == NULL)
goto out_ctx;
ctx->state = nfs4_get_open_state(r_ino, sp);
if (ctx->state == NULL)
goto out_stateowner;
set_bit(NFS_SRV_SSC_COPY_STATE, &ctx->state->flags);
memcpy(&ctx->state->open_stateid.other, &stateid->other,
NFS4_STATEID_OTHER_SIZE);
update_open_stateid(ctx->state, stateid, NULL, filep->f_mode);
set_bit(NFS_OPEN_STATE, &ctx->state->flags);
nfs_file_set_open_context(filep, ctx);
put_nfs_open_context(ctx);
file_ra_state_init(&filep->f_ra, filep->f_mapping->host->i_mapping);
res = filep;
out_free_name:
kfree(read_name);
out:
nfs_free_fattr(fattr);
return res;
out_stateowner:
nfs4_put_state_owner(sp);
out_ctx:
put_nfs_open_context(ctx);
out_filep:
fput(filep);
goto out_free_name;
}
static void __nfs42_ssc_close(struct file *filep)
{
struct nfs_open_context *ctx = nfs_file_open_context(filep);
ctx->state->flags = 0;
}
static const struct nfs4_ssc_client_ops nfs4_ssc_clnt_ops_tbl = {
.sco_open = __nfs42_ssc_open,
.sco_close = __nfs42_ssc_close,
};
/**
* nfs42_ssc_register_ops - Wrapper to register NFS_V4 ops in nfs_common
*
* Return values:
* None
*/
void nfs42_ssc_register_ops(void)
{
nfs42_ssc_register(&nfs4_ssc_clnt_ops_tbl);
}
/**
* nfs42_ssc_unregister_ops - wrapper to un-register NFS_V4 ops in nfs_common
*
* Return values:
* None.
*/
void nfs42_ssc_unregister_ops(void)
{
nfs42_ssc_unregister(&nfs4_ssc_clnt_ops_tbl);
}
#endif /* CONFIG_NFS_V4_2 */
static int nfs4_setlease(struct file *file, int arg, struct file_lease **lease,
void **priv)
{
return nfs4_proc_setlease(file, arg, lease, priv);
}
const struct file_operations nfs4_file_operations = {
.read_iter = nfs_file_read,
.write_iter = nfs_file_write,
.mmap = nfs_file_mmap,
.open = nfs4_file_open,
.flush = nfs4_file_flush,
.release = nfs_file_release,
.fsync = nfs_file_fsync,
.lock = nfs_lock,
.flock = nfs_flock,
.splice_read = nfs_file_splice_read,
.splice_write = iter_file_splice_write,
.check_flags = nfs_check_flags,
.setlease = nfs4_setlease,
#ifdef CONFIG_NFS_V4_2
.copy_file_range = nfs4_copy_file_range,
.llseek = nfs4_file_llseek,
.fallocate = nfs42_fallocate,
.remap_file_range = nfs42_remap_file_range,
#else
.llseek = nfs_file_llseek,
#endif
};
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