- 根目录:
- fs
- afs
- dir.c
/* dir.c: AFS filesystem directory handling
*
* Copyright (C) 2002 Red Hat, Inc. All Rights Reserved.
* Written by David Howells (dhowells@redhat.com)
*
* This program is free software; you can redistribute it and/or
* modify it under the terms of the GNU General Public License
* as published by the Free Software Foundation; either version
* 2 of the License, or (at your option) any later version.
*/
#include <linux/kernel.h>
#include <linux/module.h>
#include <linux/init.h>
#include <linux/fs.h>
#include <linux/namei.h>
#include <linux/pagemap.h>
#include <linux/ctype.h>
#include <linux/sched.h>
#include "internal.h"
static struct dentry *afs_lookup(struct inode *dir, struct dentry *dentry,
struct nameidata *nd);
static int afs_dir_open(struct inode *inode, struct file *file);
static int afs_readdir(struct file *file, void *dirent, filldir_t filldir);
static int afs_d_revalidate(struct dentry *dentry, struct nameidata *nd);
static int afs_d_delete(const struct dentry *dentry);
static void afs_d_release(struct dentry *dentry);
static int afs_lookup_filldir(void *_cookie, const char *name, int nlen,
loff_t fpos, u64 ino, unsigned dtype);
static int afs_create(struct inode *dir, struct dentry *dentry, int mode,
struct nameidata *nd);
static int afs_mkdir(struct inode *dir, struct dentry *dentry, int mode);
static int afs_rmdir(struct inode *dir, struct dentry *dentry);
static int afs_unlink(struct inode *dir, struct dentry *dentry);
static int afs_link(struct dentry *from, struct inode *dir,
struct dentry *dentry);
static int afs_symlink(struct inode *dir, struct dentry *dentry,
const char *content);
static int afs_rename(struct inode *old_dir, struct dentry *old_dentry,
struct inode *new_dir, struct dentry *new_dentry);
const struct file_operations afs_dir_file_operations = {
.open = afs_dir_open,
.release = afs_release,
.readdir = afs_readdir,
.lock = afs_lock,
.llseek = generic_file_llseek,
};
const struct inode_operations afs_dir_inode_operations = {
.create = afs_create,
.lookup = afs_lookup,
.link = afs_link,
.unlink = afs_unlink,
.symlink = afs_symlink,
.mkdir = afs_mkdir,
.rmdir = afs_rmdir,
.rename = afs_rename,
.permission = afs_permission,
.getattr = afs_getattr,
.setattr = afs_setattr,
};
const struct dentry_operations afs_fs_dentry_operations = {
.d_revalidate = afs_d_revalidate,
.d_delete = afs_d_delete,
.d_release = afs_d_release,
.d_automount = afs_d_automount,
};
#define AFS_DIR_HASHTBL_SIZE 128
#define AFS_DIR_DIRENT_SIZE 32
#define AFS_DIRENT_PER_BLOCK 64
union afs_dirent {
struct {
uint8_t valid;
uint8_t unused[1];
__be16 hash_next;
__be32 vnode;
__be32 unique;
uint8_t name[16];
uint8_t overflow[4]; /* if any char of the name (inc
* NUL) reaches here, consume
* the next dirent too */
} u;
uint8_t extended_name[32];
};
/* AFS directory page header (one at the beginning of every 2048-byte chunk) */
struct afs_dir_pagehdr {
__be16 npages;
__be16 magic;
#define AFS_DIR_MAGIC htons(1234)
uint8_t nentries;
uint8_t bitmap[8];
uint8_t pad[19];
};
/* directory block layout */
union afs_dir_block {
struct afs_dir_pagehdr pagehdr;
struct {
struct afs_dir_pagehdr pagehdr;
uint8_t alloc_ctrs[128];
/* dir hash table */
uint16_t hashtable[AFS_DIR_HASHTBL_SIZE];
} hdr;
union afs_dirent dirents[AFS_DIRENT_PER_BLOCK];
};
/* layout on a linux VM page */
struct afs_dir_page {
union afs_dir_block blocks[PAGE_SIZE / sizeof(union afs_dir_block)];
};
struct afs_lookup_cookie {
struct afs_fid fid;
const char *name;
size_t nlen;
int found;
};
/*
* check that a directory page is valid
*/
static inline void afs_dir_check_page(struct inode *dir, struct page *page)
{
struct afs_dir_page *dbuf;
loff_t latter;
int tmp, qty;
#if 0
/* check the page count */
qty = desc.size / sizeof(dbuf->blocks[0]);
if (qty == 0)
goto error;
if (page->index == 0 && qty != ntohs(dbuf->blocks[0].pagehdr.npages)) {
printk("kAFS: %s(%lu): wrong number of dir blocks %d!=%hu\n",
__func__, dir->i_ino, qty,
ntohs(dbuf->blocks[0].pagehdr.npages));
goto error;
}
#endif
/* determine how many magic numbers there should be in this page */
latter = dir->i_size - page_offset(page);
if (latter >= PAGE_SIZE)
qty = PAGE_SIZE;
else
qty = latter;
qty /= sizeof(union afs_dir_block);
/* check them */
dbuf = page_address(page);
for (tmp = 0; tmp < qty; tmp++) {
if (dbuf->blocks[tmp].pagehdr.magic != AFS_DIR_MAGIC) {
printk("kAFS: %s(%lu): bad magic %d/%d is %04hx\n",
__func__, dir->i_ino, tmp, qty,
ntohs(dbuf->blocks[tmp].pagehdr.magic));
goto error;
}
}
SetPageChecked(page);
return;
error:
SetPageChecked(page);
SetPageError(page);
}
/*
* discard a page cached in the pagecache
*/
static inline void afs_dir_put_page(struct page *page)
{
kunmap(page);
page_cache_release(page);
}
/*
* get a page into the pagecache
*/
static struct page *afs_dir_get_page(struct inode *dir, unsigned long index,
struct key *key)
{
struct page *page;
_enter("{%lu},%lu", dir->i_ino, index);
page = read_cache_page(dir->i_mapping, index, afs_page_filler, key);
if (!IS_ERR(page)) {
kmap(page);
if (!PageChecked(page))
afs_dir_check_page(dir, page);
if (PageError(page))
goto fail;
}
return page;
fail:
afs_dir_put_page(page);
_leave(" = -EIO");
return ERR_PTR(-EIO);
}
/*
* open an AFS directory file
*/
static int afs_dir_open(struct inode *inode, struct file *file)
{
_enter("{%lu}", inode->i_ino);
BUILD_BUG_ON(sizeof(union afs_dir_block) != 2048);
BUILD_BUG_ON(sizeof(union afs_dirent) != 32);
if (test_bit(AFS_VNODE_DELETED, &AFS_FS_I(inode)->flags))
return -ENOENT;
return afs_open(inode, file);
}
/*
* deal with one block in an AFS directory
*/
static int afs_dir_iterate_block(unsigned *fpos,
union afs_dir_block *block,
unsigned blkoff,
void *cookie,
filldir_t filldir)
{
union afs_dirent *dire;
unsigned offset, next, curr;
size_t nlen;
int tmp, ret;
_enter("%u,%x,%p,,",*fpos,blkoff,block);
curr = (*fpos - blkoff) / sizeof(union afs_dirent);
/* walk through the block, an entry at a time */
for (offset = AFS_DIRENT_PER_BLOCK - block->pagehdr.nentries;
offset < AFS_DIRENT_PER_BLOCK;
offset = next
) {
next = offset + 1;
/* skip entries marked unused in the bitmap */
if (!(block->pagehdr.bitmap[offset / 8] &
(1 << (offset % 8)))) {
_debug("ENT[%Zu.%u]: unused",
blkoff / sizeof(union afs_dir_block), offset);
if (offset >= curr)
*fpos = blkoff +
next * sizeof(union afs_dirent);
continue;
}
/* got a valid entry */
dire = &block->dirents[offset];
nlen = strnlen(dire->u.name,
sizeof(*block) -
offset * sizeof(union afs_dirent));
_debug("ENT[%Zu.%u]: %s %Zu \"%s\"",
blkoff / sizeof(union afs_dir_block), offset,
(offset < curr ? "skip" : "fill"),
nlen, dire->u.name);
/* work out where the next possible entry is */
for (tmp = nlen; tmp > 15; tmp -= sizeof(union afs_dirent)) {
if (next >= AFS_DIRENT_PER_BLOCK) {
_debug("ENT[%Zu.%u]:"
" %u travelled beyond end dir block"
" (len %u/%Zu)",
blkoff / sizeof(union afs_dir_block),
offset, next, tmp, nlen);
return -EIO;
}
if (!(block->pagehdr.bitmap[next / 8] &
(1 << (next % 8)))) {
_debug("ENT[%Zu.%u]:"
" %u unmarked extension (len %u/%Zu)",
blkoff / sizeof(union afs_dir_block),
offset, next, tmp, nlen);
return -EIO;
}
_debug("ENT[%Zu.%u]: ext %u/%Zu",
blkoff / sizeof(union afs_dir_block),
next, tmp, nlen);
next++;
}
/* skip if starts before the current position */
if (offset < curr)
continue;
/* found the next entry */
ret = filldir(cookie,
dire->u.name,
nlen,
blkoff + offset * sizeof(union afs_dirent),
ntohl(dire->u.vnode),
filldir == afs_lookup_filldir ?
ntohl(dire->u.unique) : DT_UNKNOWN);
if (ret < 0) {
_leave(" = 0 [full]");
return 0;
}
*fpos = blkoff + next * sizeof(union afs_dirent);
}
_leave(" = 1 [more]");
return 1;
}
/*
* iterate through the data blob that lists the contents of an AFS directory
*/
static int afs_dir_iterate(struct inode *dir, unsigned *fpos, void *cookie,
filldir_t filldir, struct key *key)
{
union afs_dir_block *dblock;
struct afs_dir_page *dbuf;
struct page *page;
unsigned blkoff, limit;
int ret;
_enter("{%lu},%u,,", dir->i_ino, *fpos);
if (test_bit(AFS_VNODE_DELETED, &AFS_FS_I(dir)->flags)) {
_leave(" = -ESTALE");
return -ESTALE;
}
/* round the file position up to the next entry boundary */
*fpos += sizeof(union afs_dirent) - 1;
*fpos &= ~(sizeof(union afs_dirent) - 1);
/* walk through the blocks in sequence */
ret = 0;
while (*fpos < dir->i_size) {
blkoff = *fpos & ~(sizeof(union afs_dir_block) - 1);
/* fetch the appropriate page from the directory */
page = afs_dir_get_page(dir, blkoff / PAGE_SIZE, key);
if (IS_ERR(page)) {
ret = PTR_ERR(page);
break;
}
limit = blkoff & ~(PAGE_SIZE - 1);
dbuf = page_address(page);
/* deal with the individual blocks stashed on this page */
do {
dblock = &dbuf->blocks[(blkoff % PAGE_SIZE) /
sizeof(union afs_dir_block)];
ret = afs_dir_iterate_block(fpos, dblock, blkoff,
cookie, filldir);
if (ret != 1) {
afs_dir_put_page(page);
goto out;
}
blkoff += sizeof(union afs_dir_block);
} while (*fpos < dir->i_size && blkoff < limit);
afs_dir_put_page(page);
ret = 0;
}
out:
_leave(" = %d", ret);
return ret;
}
/*
* read an AFS directory
*/
static int afs_readdir(struct file *file, void *cookie, filldir_t filldir)
{
unsigned fpos;
int ret;
_enter("{%Ld,{%lu}}",
file->f_pos, file->f_path.dentry->d_inode->i_ino);
ASSERT(file->private_data != NULL);
fpos = file->f_pos;
ret = afs_dir_iterate(file->f_path.dentry->d_inode, &fpos,
cookie, filldir, file->private_data);
file->f_pos = fpos;
_leave(" = %d", ret);
return ret;
}
/*
* search the directory for a name
* - if afs_dir_iterate_block() spots this function, it'll pass the FID
* uniquifier through dtype
*/
static int afs_lookup_filldir(void *_cookie, const char *name, int nlen,
loff_t fpos, u64 ino, unsigned dtype)
{
struct afs_lookup_cookie *cookie = _cookie;
_enter("{%s,%Zu},%s,%u,,%llu,%u",
cookie->name, cookie->nlen, name, nlen,
(unsigned long long) ino, dtype);
/* insanity checks first */
BUILD_BUG_ON(sizeof(union afs_dir_block) != 2048);
BUILD_BUG_ON(sizeof(union afs_dirent) != 32);
if (cookie->nlen != nlen || memcmp(cookie->name, name, nlen) != 0) {
_leave(" = 0 [no]");
return 0;
}
cookie->fid.vnode = ino;
cookie->fid.unique = dtype;
cookie->found = 1;
_leave(" = -1 [found]");
return -1;
}
/*
* do a lookup in a directory
* - just returns the FID the dentry name maps to if found
*/
static int afs_do_lookup(struct inode *dir, struct dentry *dentry,
struct afs_fid *fid, struct key *key)
{
struct afs_lookup_cookie cookie;
struct afs_super_info *as;
unsigned fpos;
int ret;
_enter("{%lu},%p{%s},", dir->i_ino, dentry, dentry->d_name.name);
as = dir->i_sb->s_fs_info;
/* search the directory */
cookie.name = dentry->d_name.name;
cookie.nlen = dentry->d_name.len;
cookie.fid.vid = as->volume->vid;
cookie.found = 0;
fpos = 0;
ret = afs_dir_iterate(dir, &fpos, &cookie, afs_lookup_filldir,
key);
if (ret < 0) {
_leave(" = %d [iter]", ret);
return ret;
}
ret = -ENOENT;
if (!cookie.found) {
_leave(" = -ENOENT [not found]");
return -ENOENT;
}
*fid = cookie.fid;
_leave(" = 0 { vn=%u u=%u }", fid->vnode, fid->unique);
return 0;
}
/*
* Try to auto mount the mountpoint with pseudo directory, if the autocell
* operation is setted.
*/
static struct inode *afs_try_auto_mntpt(
int ret, struct dentry *dentry, struct inode *dir, struct key *key,
struct afs_fid *fid)
{
const char *devname = dentry->d_name.name;
struct afs_vnode *vnode = AFS_FS_I(dir);
struct inode *inode;
_enter("%d, %p{%s}, {%x:%u}, %p",
ret, dentry, devname, vnode->fid.vid, vnode->fid.vnode, key);
if (ret != -ENOENT ||
!test_bit(AFS_VNODE_AUTOCELL, &vnode->flags))
goto out;
inode = afs_iget_autocell(dir, devname, strlen(devname), key);
if (IS_ERR(inode)) {
ret = PTR_ERR(inode);
goto out;
}
*fid = AFS_FS_I(inode)->fid;
_leave("= %p", inode);
return inode;
out:
_leave("= %d", ret);
return ERR_PTR(ret);
}
/*
* look up an entry in a directory
*/
static struct dentry *afs_lookup(struct inode *dir, struct dentry *dentry,
struct nameidata *nd)
{
struct afs_vnode *vnode;
struct afs_fid fid;
struct inode *inode;
struct key *key;
int ret;
vnode = AFS_FS_I(dir);
_enter("{%x:%u},%p{%s},",
vnode->fid.vid, vnode->fid.vnode, dentry, dentry->d_name.name);
ASSERTCMP(dentry->d_inode, ==, NULL);
if (dentry->d_name.len >= AFSNAMEMAX) {
_leave(" = -ENAMETOOLONG");
return ERR_PTR(-ENAMETOOLONG);
}
if (test_bit(AFS_VNODE_DELETED, &vnode->flags)) {
_leave(" = -ESTALE");
return ERR_PTR(-ESTALE);
}
key = afs_request_key(vnode->volume->cell);
if (IS_ERR(key)) {
_leave(" = %ld [key]", PTR_ERR(key));
return ERR_CAST(key);
}
ret = afs_validate(vnode, key);
if (ret < 0) {
key_put(key);
_leave(" = %d [val]", ret);
return ERR_PTR(ret);
}
ret = afs_do_lookup(dir, dentry, &fid, key);
if (ret < 0) {
inode = afs_try_auto_mntpt(ret, dentry, dir, key, &fid);
if (!IS_ERR(inode)) {
key_put(key);
goto success;
}
ret = PTR_ERR(inode);
key_put(key);
if (ret == -ENOENT) {
d_add(dentry, NULL);
_leave(" = NULL [negative]");
return NULL;
}
_leave(" = %d [do]", ret);
return ERR_PTR(ret);
}
dentry->d_fsdata = (void *)(unsigned long) vnode->status.data_version;
/* instantiate the dentry */
inode = afs_iget(dir->i_sb, key, &fid, NULL, NULL);
key_put(key);
if (IS_ERR(inode)) {
_leave(" = %ld", PTR_ERR(inode));
return ERR_CAST(inode);
}
success:
d_add(dentry, inode);
_leave(" = 0 { vn=%u u=%u } -> { ino=%lu v=%u }",
fid.vnode,
fid.unique,
dentry->d_inode->i_ino,
dentry->d_inode->i_generation);
return NULL;
}
/*
* check that a dentry lookup hit has found a valid entry
* - NOTE! the hit can be a negative hit too, so we can't assume we have an
* inode
*/
static int afs_d_revalidate(struct dentry *dentry, struct nameidata *nd)
{
struct afs_vnode *vnode, *dir;
struct afs_fid uninitialized_var(fid);
struct dentry *parent;
struct key *key;
void *dir_version;
int ret;
if (nd->flags & LOOKUP_RCU)
return -ECHILD;
vnode = AFS_FS_I(dentry->d_inode);
if (dentry->d_inode)
_enter("{v={%x:%u} n=%s fl=%lx},",
vnode->fid.vid, vnode->fid.vnode, dentry->d_name.name,
vnode->flags);
else
_enter("{neg n=%s}", dentry->d_name.name);
key = afs_request_key(AFS_FS_S(dentry->d_sb)->volume->cell);
if (IS_ERR(key))
key = NULL;
/* lock down the parent dentry so we can peer at it */
parent = dget_parent(dentry);
if (!parent->d_inode)
goto out_bad;
dir = AFS_FS_I(parent->d_inode);
/* validate the parent directory */
if (test_bit(AFS_VNODE_MODIFIED, &dir->flags))
afs_validate(dir, key);
if (test_bit(AFS_VNODE_DELETED, &dir->flags)) {
_debug("%s: parent dir deleted", dentry->d_name.name);
goto out_bad;
}
dir_version = (void *) (unsigned long) dir->status.data_version;
if (dentry->d_fsdata == dir_version)
goto out_valid; /* the dir contents are unchanged */
_debug("dir modified");
/* search the directory for this vnode */
ret = afs_do_lookup(&dir->vfs_inode, dentry, &fid, key);
switch (ret) {
case 0:
/* the filename maps to something */
if (!dentry->d_inode)
goto out_bad;
if (is_bad_inode(dentry->d_inode)) {
printk("kAFS: afs_d_revalidate: %s/%s has bad inode\n",
parent->d_name.name, dentry->d_name.name);
goto out_bad;
}
/* if the vnode ID has changed, then the dirent points to a
* different file */
if (fid.vnode != vnode->fid.vnode) {
_debug("%s: dirent changed [%u != %u]",
dentry->d_name.name, fid.vnode,
vnode->fid.vnode);
goto not_found;
}
/* if the vnode ID uniqifier has changed, then the file has
* been deleted and replaced, and the original vnode ID has
* been reused */
if (fid.unique != vnode->fid.unique) {
_debug("%s: file deleted (uq %u -> %u I:%u)",
dentry->d_name.name, fid.unique,
vnode->fid.unique,
dentry->d_inode->i_generation);
spin_lock(&vnode->lock);
set_bit(AFS_VNODE_DELETED, &vnode->flags);
spin_unlock(&vnode->lock);
goto not_found;
}
goto out_valid;
case -ENOENT:
/* the filename is unknown */
_debug("%s: dirent not found", dentry->d_name.name);
if (dentry->d_inode)
goto not_found;
goto out_valid;
default:
_debug("failed to iterate dir %s: %d",
parent->d_name.name, ret);
goto out_bad;
}
out_valid:
dentry->d_fsdata = dir_version;
out_skip:
dput(parent);
key_put(key);
_leave(" = 1 [valid]");
return 1;
/* the dirent, if it exists, now points to a different vnode */
not_found:
spin_lock(&dentry->d_lock);
dentry->d_flags |= DCACHE_NFSFS_RENAMED;
spin_unlock(&dentry->d_lock);
out_bad:
if (dentry->d_inode) {
/* don't unhash if we have submounts */
if (have_submounts(dentry))
goto out_skip;
}
_debug("dropping dentry %s/%s",
parent->d_name.name, dentry->d_name.name);
shrink_dcache_parent(dentry);
d_drop(dentry);
dput(parent);
key_put(key);
_leave(" = 0 [bad]");
return 0;
}
/*
* allow the VFS to enquire as to whether a dentry should be unhashed (mustn't
* sleep)
* - called from dput() when d_count is going to 0.
* - return 1 to request dentry be unhashed, 0 otherwise
*/
static int afs_d_delete(const struct dentry *dentry)
{
_enter("%s", dentry->d_name.name);
if (dentry->d_flags & DCACHE_NFSFS_RENAMED)
goto zap;
if (dentry->d_inode &&
(test_bit(AFS_VNODE_DELETED, &AFS_FS_I(dentry->d_inode)->flags) ||
test_bit(AFS_VNODE_PSEUDODIR, &AFS_FS_I(dentry->d_inode)->flags)))
goto zap;
_leave(" = 0 [keep]");
return 0;
zap:
_leave(" = 1 [zap]");
return 1;
}
/*
* handle dentry release
*/
static void afs_d_release(struct dentry *dentry)
{
_enter("%s", dentry->d_name.name);
}
/*
* create a directory on an AFS filesystem
*/
static int afs_mkdir(struct inode *dir, struct dentry *dentry, int mode)
{
struct afs_file_status status;
struct afs_callback cb;
struct afs_server *server;
struct afs_vnode *dvnode, *vnode;
struct afs_fid fid;
struct inode *inode;
struct key *key;
int ret;
dvnode = AFS_FS_I(dir);
_enter("{%x:%u},{%s},%o",
dvnode->fid.vid, dvnode->fid.vnode, dentry->d_name.name, mode);
ret = -ENAMETOOLONG;
if (dentry->d_name.len >= AFSNAMEMAX)
goto error;
key = afs_request_key(dvnode->volume->cell);
if (IS_ERR(key)) {
ret = PTR_ERR(key);
goto error;
}
mode |= S_IFDIR;
ret = afs_vnode_create(dvnode, key, dentry->d_name.name,
mode, &fid, &status, &cb, &server);
if (ret < 0)
goto mkdir_error;
inode = afs_iget(dir->i_sb, key, &fid, &status, &cb);
if (IS_ERR(inode)) {
/* ENOMEM at a really inconvenient time - just abandon the new
* directory on the server */
ret = PTR_ERR(inode);
goto iget_error;
}
/* apply the status report we've got for the new vnode */
vnode = AFS_FS_I(inode);
spin_lock(&vnode->lock);
vnode->update_cnt++;
spin_unlock(&vnode->lock);
afs_vnode_finalise_status_update(vnode, server);
afs_put_server(server);
d_instantiate(dentry, inode);
if (d_unhashed(dentry)) {
_debug("not hashed");
d_rehash(dentry);
}
key_put(key);
_leave(" = 0");
return 0;
iget_error:
afs_put_server(server);
mkdir_error:
key_put(key);
error:
d_drop(dentry);
_leave(" = %d", ret);
return ret;
}
/*
* remove a directory from an AFS filesystem
*/
static int afs_rmdir(struct inode *dir, struct dentry *dentry)
{
struct afs_vnode *dvnode, *vnode;
struct key *key;
int ret;
dvnode = AFS_FS_I(dir);
_enter("{%x:%u},{%s}",
dvnode->fid.vid, dvnode->fid.vnode, dentry->d_name.name);
ret = -ENAMETOOLONG;
if (dentry->d_name.len >= AFSNAMEMAX)
goto error;
key = afs_request_key(dvnode->volume->cell);
if (IS_ERR(key)) {
ret = PTR_ERR(key);
goto error;
}
ret = afs_vnode_remove(dvnode, key, dentry->d_name.name, true);
if (ret < 0)
goto rmdir_error;
if (dentry->d_inode) {
vnode = AFS_FS_I(dentry->d_inode);
clear_nlink(&vnode->vfs_inode);
set_bit(AFS_VNODE_DELETED, &vnode->flags);
afs_discard_callback_on_delete(vnode);
}
key_put(key);
_leave(" = 0");
return 0;
rmdir_error:
key_put(key);
error:
_leave(" = %d", ret);
return ret;
}
/*
* remove a file from an AFS filesystem
*/
static int afs_unlink(struct inode *dir, struct dentry *dentry)
{
struct afs_vnode *dvnode, *vnode;
struct key *key;
int ret;
dvnode = AFS_FS_I(dir);
_enter("{%x:%u},{%s}",
dvnode->fid.vid, dvnode->fid.vnode, dentry->d_name.name);
ret = -ENAMETOOLONG;
if (dentry->d_name.len >= AFSNAMEMAX)
goto error;
key = afs_request_key(dvnode->volume->cell);
if (IS_ERR(key)) {
ret = PTR_ERR(key);
goto error;
}
if (dentry->d_inode) {
vnode = AFS_FS_I(dentry->d_inode);
/* make sure we have a callback promise on the victim */
ret = afs_validate(vnode, key);
if (ret < 0)
goto error;
}
ret = afs_vnode_remove(dvnode, key, dentry->d_name.name, false);
if (ret < 0)
goto remove_error;
if (dentry->d_inode) {
/* if the file wasn't deleted due to excess hard links, the
* fileserver will break the callback promise on the file - if
* it had one - before it returns to us, and if it was deleted,
* it won't
*
* however, if we didn't have a callback promise outstanding,
* or it was outstanding on a different server, then it won't
* break it either...
*/
vnode = AFS_FS_I(dentry->d_inode);
if (test_bit(AFS_VNODE_DELETED, &vnode->flags))
_debug("AFS_VNODE_DELETED");
if (test_bit(AFS_VNODE_CB_BROKEN, &vnode->flags))
_debug("AFS_VNODE_CB_BROKEN");
set_bit(AFS_VNODE_CB_BROKEN, &vnode->flags);
ret = afs_validate(vnode, key);
_debug("nlink %d [val %d]", vnode->vfs_inode.i_nlink, ret);
}
key_put(key);
_leave(" = 0");
return 0;
remove_error:
key_put(key);
error:
_leave(" = %d", ret);
return ret;
}
/*
* create a regular file on an AFS filesystem
*/
static int afs_create(struct inode *dir, struct dentry *dentry, int mode,
struct nameidata *nd)
{
struct afs_file_status status;
struct afs_callback cb;
struct afs_server *server;
struct afs_vnode *dvnode, *vnode;
struct afs_fid fid;
struct inode *inode;
struct key *key;
int ret;
dvnode = AFS_FS_I(dir);
_enter("{%x:%u},{%s},%o,",
dvnode->fid.vid, dvnode->fid.vnode, dentry->d_name.name, mode);
ret = -ENAMETOOLONG;
if (dentry->d_name.len >= AFSNAMEMAX)
goto error;
key = afs_request_key(dvnode->volume->cell);
if (IS_ERR(key)) {
ret = PTR_ERR(key);
goto error;
}
mode |= S_IFREG;
ret = afs_vnode_create(dvnode, key, dentry->d_name.name,
mode, &fid, &status, &cb, &server);
if (ret < 0)
goto create_error;
inode = afs_iget(dir->i_sb, key, &fid, &status, &cb);
if (IS_ERR(inode)) {
/* ENOMEM at a really inconvenient time - just abandon the new
* directory on the server */
ret = PTR_ERR(inode);
goto iget_error;
}
/* apply the status report we've got for the new vnode */
vnode = AFS_FS_I(inode);
spin_lock(&vnode->lock);
vnode->update_cnt++;
spin_unlock(&vnode->lock);
afs_vnode_finalise_status_update(vnode, server);
afs_put_server(server);
d_instantiate(dentry, inode);
if (d_unhashed(dentry)) {
_debug("not hashed");
d_rehash(dentry);
}
key_put(key);
_leave(" = 0");
return 0;
iget_error:
afs_put_server(server);
create_error:
key_put(key);
error:
d_drop(dentry);
_leave(" = %d", ret);
return ret;
}
/*
* create a hard link between files in an AFS filesystem
*/
static int afs_link(struct dentry *from, struct inode *dir,
struct dentry *dentry)
{
struct afs_vnode *dvnode, *vnode;
struct key *key;
int ret;
vnode = AFS_FS_I(from->d_inode);
dvnode = AFS_FS_I(dir);
_enter("{%x:%u},{%x:%u},{%s}",
vnode->fid.vid, vnode->fid.vnode,
dvnode->fid.vid, dvnode->fid.vnode,
dentry->d_name.name);
ret = -ENAMETOOLONG;
if (dentry->d_name.len >= AFSNAMEMAX)
goto error;
key = afs_request_key(dvnode->volume->cell);
if (IS_ERR(key)) {
ret = PTR_ERR(key);
goto error;
}
ret = afs_vnode_link(dvnode, vnode, key, dentry->d_name.name);
if (ret < 0)
goto link_error;
ihold(&vnode->vfs_inode);
d_instantiate(dentry, &vnode->vfs_inode);
key_put(key);
_leave(" = 0");
return 0;
link_error:
key_put(key);
error:
d_drop(dentry);
_leave(" = %d", ret);
return ret;
}
/*
* create a symlink in an AFS filesystem
*/
static int afs_symlink(struct inode *dir, struct dentry *dentry,
const char *content)
{
struct afs_file_status status;
struct afs_server *server;
struct afs_vnode *dvnode, *vnode;
struct afs_fid fid;
struct inode *inode;
struct key *key;
int ret;
dvnode = AFS_FS_I(dir);
_enter("{%x:%u},{%s},%s",
dvnode->fid.vid, dvnode->fid.vnode, dentry->d_name.name,
content);
ret = -ENAMETOOLONG;
if (dentry->d_name.len >= AFSNAMEMAX)
goto error;
ret = -EINVAL;
if (strlen(content) >= AFSPATHMAX)
goto error;
key = afs_request_key(dvnode->volume->cell);
if (IS_ERR(key)) {
ret = PTR_ERR(key);
goto error;
}
ret = afs_vnode_symlink(dvnode, key, dentry->d_name.name, content,
&fid, &status, &server);
if (ret < 0)
goto create_error;
inode = afs_iget(dir->i_sb, key, &fid, &status, NULL);
if (IS_ERR(inode)) {
/* ENOMEM at a really inconvenient time - just abandon the new
* directory on the server */
ret = PTR_ERR(inode);
goto iget_error;
}
/* apply the status report we've got for the new vnode */
vnode = AFS_FS_I(inode);
spin_lock(&vnode->lock);
vnode->update_cnt++;
spin_unlock(&vnode->lock);
afs_vnode_finalise_status_update(vnode, server);
afs_put_server(server);
d_instantiate(dentry, inode);
if (d_unhashed(dentry)) {
_debug("not hashed");
d_rehash(dentry);
}
key_put(key);
_leave(" = 0");
return 0;
iget_error:
afs_put_server(server);
create_error:
key_put(key);
error:
d_drop(dentry);
_leave(" = %d", ret);
return ret;
}
/*
* rename a file in an AFS filesystem and/or move it between directories
*/
static int afs_rename(struct inode *old_dir, struct dentry *old_dentry,
struct inode *new_dir, struct dentry *new_dentry)
{
struct afs_vnode *orig_dvnode, *new_dvnode, *vnode;
struct key *key;
int ret;
vnode = AFS_FS_I(old_dentry->d_inode);
orig_dvnode = AFS_FS_I(old_dir);
new_dvnode = AFS_FS_I(new_dir);
_enter("{%x:%u},{%x:%u},{%x:%u},{%s}",
orig_dvnode->fid.vid, orig_dvnode->fid.vnode,
vnode->fid.vid, vnode->fid.vnode,
new_dvnode->fid.vid, new_dvnode->fid.vnode,
new_dentry->d_name.name);
ret = -ENAMETOOLONG;
if (new_dentry->d_name.len >= AFSNAMEMAX)
goto error;
key = afs_request_key(orig_dvnode->volume->cell);
if (IS_ERR(key)) {
ret = PTR_ERR(key);
goto error;
}
ret = afs_vnode_rename(orig_dvnode, new_dvnode, key,
old_dentry->d_name.name,
new_dentry->d_name.name);
if (ret < 0)
goto rename_error;
key_put(key);
_leave(" = 0");
return 0;
rename_error:
key_put(key);
error:
d_drop(new_dentry);
_leave(" = %d", ret);
return ret;
}