static const char *nfs_get_link(struct dentry *dentry,
struct inode *inode,
struct delayed_call *done)
{
struct page *page;
void *err;
if (!dentry) {
err = ERR_PTR(nfs_revalidate_mapping_rcu(inode));
if (err)
return err;
page = find_get_page(inode->i_mapping, 0);
if (!page)
return ERR_PTR(-ECHILD);
if (!PageUptodate(page)) {
put_page(page);
return ERR_PTR(-ECHILD);
}
} else {
err = ERR_PTR(nfs_revalidate_mapping(inode, inode->i_mapping));
if (err)
return err;
page = read_cache_page(&inode->i_data, 0, nfs_symlink_filler,
inode);
if (IS_ERR(page))
return ERR_CAST(page);
}
set_delayed_call(done, page_put_link, page);
return page_address(page);
}
static void *nfs_follow_link(struct dentry *dentry, struct nameidata *nd)
{
struct inode *inode = dentry->d_inode;
struct page *page;
void *err = ERR_PTR(nfs_revalidate_mapping(inode, inode->i_mapping));
if (err)
goto read_failed;
page = read_cache_page(&inode->i_data, 0,
(filler_t *)nfs_symlink_filler, inode);
if (IS_ERR(page)) {
err = page;
goto read_failed;
}
if (!PageUptodate(page)) {
err = ERR_PTR(-EIO);
goto getlink_read_error;
}
nd_set_link(nd, kmap(page));
return page;
getlink_read_error:
page_cache_release(page);
read_failed:
nd_set_link(nd, err);
return NULL;
}
/**
* nfs_revalidate_file - Revalidate the page cache & related metadata
* @inode - pointer to inode struct
* @file - pointer to file
*/
static int nfs_revalidate_file(struct inode *inode, struct file *filp)
{
struct nfs_inode *nfsi = NFS_I(inode);
int retval = 0;
if ((nfsi->cache_validity & NFS_INO_REVAL_PAGECACHE) || nfs_attribute_timeout(inode))
retval = __nfs_revalidate_inode(NFS_SERVER(inode), inode);
nfs_revalidate_mapping(inode, filp->f_mapping);
return 0;
}
static int
nfs_file_mmap(struct file * file, struct vm_area_struct * vma)
{
struct dentry *dentry = file->f_path.dentry;
struct inode *inode = dentry->d_inode;
int status;
dfprintk(VFS, "nfs: mmap(%s/%s)\n",
dentry->d_parent->d_name.name, dentry->d_name.name);
status = nfs_revalidate_mapping(inode, file->f_mapping);
if (!status)
status = generic_file_mmap(file, vma);
return status;
}
static ssize_t
nfs_file_sendfile(struct file *filp, loff_t *ppos, size_t count,
read_actor_t actor, void *target)
{
struct dentry *dentry = filp->f_path.dentry;
struct inode *inode = dentry->d_inode;
ssize_t res;
dfprintk(VFS, "nfs: sendfile(%s/%s, %lu@%Lu)\n",
dentry->d_parent->d_name.name, dentry->d_name.name,
(unsigned long) count, (unsigned long long) *ppos);
res = nfs_revalidate_mapping(inode, filp->f_mapping);
if (!res)
res = generic_file_sendfile(filp, ppos, count, actor, target);
return res;
}
static ssize_t
nfs_file_splice_read(struct file *filp, loff_t *ppos,
struct pipe_inode_info *pipe, size_t count,
unsigned int flags)
{
struct dentry *dentry = filp->f_path.dentry;
struct inode *inode = dentry->d_inode;
ssize_t res;
dprintk("NFS: splice_read(%s/%s, %lu@%Lu)\n",
dentry->d_parent->d_name.name, dentry->d_name.name,
(unsigned long) count, (unsigned long long) *ppos);
res = nfs_revalidate_mapping(inode, filp->f_mapping);
if (!res)
res = generic_file_splice_read(filp, ppos, pipe, count, flags);
return res;
}
int
nfs_file_mmap(struct file * file, struct vm_area_struct * vma)
{
struct inode *inode = file_inode(file);
int status;
dprintk("NFS: mmap(%pD2)\n", file);
/* Note: generic_file_mmap() returns ENOSYS on nommu systems
* so we call that before revalidating the mapping
*/
status = generic_file_mmap(file, vma);
if (!status) {
vma->vm_ops = &nfs_file_vm_ops;
status = nfs_revalidate_mapping(inode, file->f_mapping);
}
return status;
}
static int
nfs_file_mmap(struct file * file, struct vm_area_struct * vma)
{
struct dentry *dentry = file->f_path.dentry;
struct inode *inode = dentry->d_inode;
int status;
dprintk("NFS: mmap(%s/%s)\n",
dentry->d_parent->d_name.name, dentry->d_name.name);
status = nfs_revalidate_mapping(inode, file->f_mapping);
if (!status) {
vma->vm_ops = &nfs_file_vm_ops;
vma->vm_flags |= VM_CAN_NONLINEAR;
file_accessed(file);
}
return status;
}
ssize_t
nfs_file_splice_read(struct file *filp, loff_t *ppos,
struct pipe_inode_info *pipe, size_t count,
unsigned int flags)
{
struct inode *inode = file_inode(filp);
ssize_t res;
dprintk("NFS: splice_read(%pD2, %lu@%Lu)\n",
filp, (unsigned long) count, (unsigned long long) *ppos);
res = nfs_revalidate_mapping(inode, filp->f_mapping);
if (!res) {
res = generic_file_splice_read(filp, ppos, pipe, count, flags);
if (res > 0)
nfs_add_stats(inode, NFSIOS_NORMALREADBYTES, res);
}
return res;
}
static int
nfs_file_mmap(struct file * file, struct vm_area_struct * vma)
{
struct dentry *dentry = file->f_path.dentry;
struct inode *inode = dentry->d_inode;
int status;
dprintk("NFS: mmap(%s/%s)\n",
dentry->d_parent->d_name.name, dentry->d_name.name);
/* Note: generic_file_mmap() returns ENOSYS on nommu systems
* so we call that before revalidating the mapping
*/
status = generic_file_mmap(file, vma);
if (!status) {
vma->vm_ops = &nfs_file_vm_ops;
status = nfs_revalidate_mapping(inode, file->f_mapping);
}
return status;
}
/*
* Write to a file (through the page cache).
*/
static ssize_t
nfs_file_write(struct kiocb *iocb, const char __user *buf, size_t count, loff_t pos)
{
struct dentry * dentry = iocb->ki_filp->f_dentry;
struct inode * inode = dentry->d_inode;
ssize_t result;
#ifdef CONFIG_NFS_DIRECTIO
if (iocb->ki_filp->f_flags & O_DIRECT)
return nfs_file_direct_write(iocb, buf, count, pos);
#endif
dfprintk(VFS, "nfs: write(%s/%s(%ld), %lu@%lu)\n",
dentry->d_parent->d_name.name, dentry->d_name.name,
inode->i_ino, (unsigned long) count, (unsigned long) pos);
result = -EBUSY;
if (IS_SWAPFILE(inode))
goto out_swapfile;
/*
* O_APPEND implies that we must revalidate the file length.
*/
if (iocb->ki_filp->f_flags & O_APPEND) {
result = nfs_revalidate_file_size(inode, iocb->ki_filp);
if (result)
goto out;
}
nfs_revalidate_mapping(inode, iocb->ki_filp->f_mapping);
result = count;
if (!count)
goto out;
result = generic_file_aio_write(iocb, buf, count, pos);
out:
return result;
out_swapfile:
printk(KERN_INFO "NFS: attempt to write to active swap file!\n");
goto out;
}
ssize_t
nfs_file_read(struct kiocb *iocb, struct iov_iter *to)
{
struct inode *inode = file_inode(iocb->ki_filp);
ssize_t result;
if (iocb->ki_filp->f_flags & O_DIRECT)
return nfs_file_direct_read(iocb, to, iocb->ki_pos);
dprintk("NFS: read(%pD2, %zu@%lu)\n",
iocb->ki_filp,
iov_iter_count(to), (unsigned long) iocb->ki_pos);
result = nfs_revalidate_mapping(inode, iocb->ki_filp->f_mapping);
if (!result) {
result = generic_file_read_iter(iocb, to);
if (result > 0)
nfs_add_stats(inode, NFSIOS_NORMALREADBYTES, result);
}
return result;
}
static ssize_t
nfs_file_read(struct kiocb *iocb, const struct iovec *iov,
unsigned long nr_segs, loff_t pos)
{
struct dentry * dentry = iocb->ki_filp->f_path.dentry;
struct inode * inode = dentry->d_inode;
ssize_t result;
size_t count = iov_length(iov, nr_segs);
if (iocb->ki_filp->f_flags & O_DIRECT)
return nfs_file_direct_read(iocb, iov, nr_segs, pos);
dprintk("NFS: read(%s/%s, %lu@%lu)\n",
dentry->d_parent->d_name.name, dentry->d_name.name,
(unsigned long) count, (unsigned long) pos);
result = nfs_revalidate_mapping(inode, iocb->ki_filp->f_mapping);
nfs_add_stats(inode, NFSIOS_NORMALREADBYTES, count);
if (!result)
result = generic_file_aio_read(iocb, iov, nr_segs, pos);
return result;
}
