blob: e92595eff1b81fc71e33fc7cee4516d715de58a2 [file] [log] [blame]
/*
* 2007+ Copyright (c) Evgeniy Polyakov <zbr@ioremap.net>
* All rights reserved.
*
* 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.
*
* This program is distributed in the hope that it will be useful,
* but WITHOUT ANY WARRANTY; without even the implied warranty of
* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
* GNU General Public License for more details.
*/
#include <linux/module.h>
#include <linux/backing-dev.h>
#include <linux/crypto.h>
#include <linux/fs.h>
#include <linux/jhash.h>
#include <linux/hash.h>
#include <linux/ktime.h>
#include <linux/mm.h>
#include <linux/mount.h>
#include <linux/pagemap.h>
#include <linux/pagevec.h>
#include <linux/parser.h>
#include <linux/swap.h>
#include <linux/slab.h>
#include <linux/statfs.h>
#include <linux/writeback.h>
#include <linux/quotaops.h>
#include "netfs.h"
#define POHMELFS_MAGIC_NUM 0x504f482e
static struct kmem_cache *pohmelfs_inode_cache;
static atomic_t psb_bdi_num = ATOMIC_INIT(0);
/*
* Removes inode from all trees, drops local name cache and removes all queued
* requests for object removal.
*/
void pohmelfs_inode_del_inode(struct pohmelfs_sb *psb, struct pohmelfs_inode *pi)
{
mutex_lock(&pi->offset_lock);
pohmelfs_free_names(pi);
mutex_unlock(&pi->offset_lock);
dprintk("%s: deleted stuff in ino: %llu.\n", __func__, pi->ino);
}
/*
* Sync inode to server.
* Returns zero in success and negative error value otherwise.
* It will gather path to root directory into structures containing
* creation mode, permissions and names, so that the whole path
* to given inode could be created using only single network command.
*/
int pohmelfs_write_inode_create(struct inode *inode, struct netfs_trans *trans)
{
struct pohmelfs_inode *pi = POHMELFS_I(inode);
int err = -ENOMEM, size;
struct netfs_cmd *cmd;
void *data;
int cur_len = netfs_trans_cur_len(trans);
if (unlikely(cur_len < 0))
return -ETOOSMALL;
cmd = netfs_trans_current(trans);
cur_len -= sizeof(struct netfs_cmd);
data = (void *)(cmd + 1);
err = pohmelfs_construct_path_string(pi, data, cur_len);
if (err < 0)
goto err_out_exit;
size = err;
cmd->start = i_size_read(inode);
cmd->cmd = NETFS_CREATE;
cmd->size = size;
cmd->id = pi->ino;
cmd->ext = inode->i_mode;
netfs_convert_cmd(cmd);
netfs_trans_update(cmd, trans, size);
return 0;
err_out_exit:
printk("%s: completed ino: %llu, err: %d.\n", __func__, pi->ino, err);
return err;
}
static int pohmelfs_write_trans_complete(struct page **pages, unsigned int page_num,
void *private, int err)
{
unsigned i;
dprintk("%s: pages: %lu-%lu, page_num: %u, err: %d.\n",
__func__, pages[0]->index, pages[page_num-1]->index,
page_num, err);
for (i = 0; i < page_num; i++) {
struct page *page = pages[i];
if (!page)
continue;
end_page_writeback(page);
if (err < 0) {
SetPageError(page);
set_page_dirty(page);
}
unlock_page(page);
page_cache_release(page);
/* dprintk("%s: %3u/%u: page: %p.\n", __func__, i, page_num, page); */
}
return err;
}
static int pohmelfs_inode_has_dirty_pages(struct address_space *mapping, pgoff_t index)
{
int ret;
struct page *page;
rcu_read_lock();
ret = radix_tree_gang_lookup_tag(&mapping->page_tree,
(void **)&page, index, 1, PAGECACHE_TAG_DIRTY);
rcu_read_unlock();
return ret;
}
static int pohmelfs_writepages(struct address_space *mapping, struct writeback_control *wbc)
{
struct inode *inode = mapping->host;
struct pohmelfs_inode *pi = POHMELFS_I(inode);
struct pohmelfs_sb *psb = POHMELFS_SB(inode->i_sb);
int err = 0;
int done = 0;
int nr_pages;
pgoff_t index;
pgoff_t end; /* Inclusive */
int scanned = 0;
int range_whole = 0;
if (wbc->range_cyclic) {
index = mapping->writeback_index; /* Start from prev offset */
end = -1;
} else {
index = wbc->range_start >> PAGE_CACHE_SHIFT;
end = wbc->range_end >> PAGE_CACHE_SHIFT;
if (wbc->range_start == 0 && wbc->range_end == LLONG_MAX)
range_whole = 1;
scanned = 1;
}
retry:
while (!done && (index <= end)) {
unsigned int i = min(end - index, (pgoff_t)psb->trans_max_pages);
int path_len;
struct netfs_trans *trans;
err = pohmelfs_inode_has_dirty_pages(mapping, index);
if (!err)
break;
err = pohmelfs_path_length(pi);
if (err < 0)
break;
path_len = err;
if (path_len <= 2) {
err = -ENOENT;
break;
}
trans = netfs_trans_alloc(psb, path_len, 0, i);
if (!trans) {
err = -ENOMEM;
break;
}
trans->complete = &pohmelfs_write_trans_complete;
trans->page_num = nr_pages = find_get_pages_tag(mapping, &index,
PAGECACHE_TAG_DIRTY, trans->page_num,
trans->pages);
dprintk("%s: t: %p, nr_pages: %u, end: %lu, index: %lu, max: %u.\n",
__func__, trans, nr_pages, end, index, trans->page_num);
if (!nr_pages)
goto err_out_reset;
err = pohmelfs_write_inode_create(inode, trans);
if (err)
goto err_out_reset;
err = 0;
scanned = 1;
for (i = 0; i < trans->page_num; i++) {
struct page *page = trans->pages[i];
lock_page(page);
if (unlikely(page->mapping != mapping))
goto out_continue;
if (!wbc->range_cyclic && page->index > end) {
done = 1;
goto out_continue;
}
if (wbc->sync_mode != WB_SYNC_NONE)
wait_on_page_writeback(page);
if (PageWriteback(page) ||
!clear_page_dirty_for_io(page)) {
dprintk("%s: not clear for io page: %p, writeback: %d.\n",
__func__, page, PageWriteback(page));
goto out_continue;
}
set_page_writeback(page);
trans->attached_size += page_private(page);
trans->attached_pages++;
#if 0
dprintk("%s: %u/%u added trans: %p, gen: %u, page: %p, [High: %d], size: %lu, idx: %lu.\n",
__func__, i, trans->page_num, trans, trans->gen, page,
!!PageHighMem(page), page_private(page), page->index);
#endif
wbc->nr_to_write--;
if (wbc->nr_to_write <= 0)
done = 1;
continue;
out_continue:
unlock_page(page);
trans->pages[i] = NULL;
}
err = netfs_trans_finish(trans, psb);
if (err)
break;
continue;
err_out_reset:
trans->result = err;
netfs_trans_reset(trans);
netfs_trans_put(trans);
break;
}
if (!scanned && !done) {
/*
* We hit the last page and there is more work to be done: wrap
* back to the start of the file
*/
scanned = 1;
index = 0;
goto retry;
}
if (wbc->range_cyclic || (range_whole && wbc->nr_to_write > 0))
mapping->writeback_index = index;
return err;
}
/*
* Inode writeback creation completion callback.
* Only invoked for just created inodes, which do not have pages attached,
* like dirs and empty files.
*/
static int pohmelfs_write_inode_complete(struct page **pages, unsigned int page_num,
void *private, int err)
{
struct inode *inode = private;
struct pohmelfs_inode *pi = POHMELFS_I(inode);
if (inode) {
if (err) {
mark_inode_dirty(inode);
clear_bit(NETFS_INODE_REMOTE_SYNCED, &pi->state);
} else {
set_bit(NETFS_INODE_REMOTE_SYNCED, &pi->state);
}
pohmelfs_put_inode(pi);
}
return err;
}
int pohmelfs_write_create_inode(struct pohmelfs_inode *pi)
{
struct netfs_trans *t;
struct inode *inode = &pi->vfs_inode;
struct pohmelfs_sb *psb = POHMELFS_SB(inode->i_sb);
int err;
if (test_bit(NETFS_INODE_REMOTE_SYNCED, &pi->state))
return 0;
dprintk("%s: started ino: %llu.\n", __func__, pi->ino);
err = pohmelfs_path_length(pi);
if (err < 0)
goto err_out_exit;
t = netfs_trans_alloc(psb, err + 1, 0, 0);
if (!t) {
err = -ENOMEM;
goto err_out_exit;
}
t->complete = pohmelfs_write_inode_complete;
t->private = igrab(inode);
if (!t->private) {
err = -ENOENT;
goto err_out_put;
}
err = pohmelfs_write_inode_create(inode, t);
if (err)
goto err_out_put;
netfs_trans_finish(t, POHMELFS_SB(inode->i_sb));
return 0;
err_out_put:
t->result = err;
netfs_trans_put(t);
err_out_exit:
return err;
}
/*
* Sync all not-yet-created children in given directory to the server.
*/
static int pohmelfs_write_inode_create_children(struct inode *inode)
{
struct pohmelfs_inode *parent = POHMELFS_I(inode);
struct super_block *sb = inode->i_sb;
struct pohmelfs_name *n;
while (!list_empty(&parent->sync_create_list)) {
n = NULL;
mutex_lock(&parent->offset_lock);
if (!list_empty(&parent->sync_create_list)) {
n = list_first_entry(&parent->sync_create_list,
struct pohmelfs_name, sync_create_entry);
list_del_init(&n->sync_create_entry);
}
mutex_unlock(&parent->offset_lock);
if (!n)
break;
inode = ilookup(sb, n->ino);
dprintk("%s: parent: %llu, ino: %llu, inode: %p.\n",
__func__, parent->ino, n->ino, inode);
if (inode && (inode->i_state & I_DIRTY)) {
struct pohmelfs_inode *pi = POHMELFS_I(inode);
pohmelfs_write_create_inode(pi);
/* pohmelfs_meta_command(pi, NETFS_INODE_INFO, 0, NULL, NULL, 0); */
iput(inode);
}
}
return 0;
}
/*
* Removes given child from given inode on server.
*/
int pohmelfs_remove_child(struct pohmelfs_inode *pi, struct pohmelfs_name *n)
{
return pohmelfs_meta_command_data(pi, pi->ino, NETFS_REMOVE, NULL, 0, NULL, NULL, 0);
}
/*
* Writeback for given inode.
*/
static int pohmelfs_write_inode(struct inode *inode,
struct writeback_control *wbc)
{
struct pohmelfs_inode *pi = POHMELFS_I(inode);
pohmelfs_write_create_inode(pi);
pohmelfs_write_inode_create_children(inode);
return 0;
}
/*
* It is not exported, sorry...
*/
static inline wait_queue_head_t *page_waitqueue(struct page *page)
{
const struct zone *zone = page_zone(page);
return &zone->wait_table[hash_ptr(page, zone->wait_table_bits)];
}
static int pohmelfs_wait_on_page_locked(struct page *page)
{
struct pohmelfs_sb *psb = POHMELFS_SB(page->mapping->host->i_sb);
long ret = psb->wait_on_page_timeout;
DEFINE_WAIT_BIT(wait, &page->flags, PG_locked);
int err = 0;
if (!PageLocked(page))
return 0;
for (;;) {
prepare_to_wait(page_waitqueue(page),
&wait.wait, TASK_INTERRUPTIBLE);
dprintk("%s: page: %p, locked: %d, uptodate: %d, error: %d, flags: %lx.\n",
__func__, page, PageLocked(page), PageUptodate(page),
PageError(page), page->flags);
if (!PageLocked(page))
break;
if (!signal_pending(current)) {
ret = schedule_timeout(ret);
if (!ret)
break;
continue;
}
ret = -ERESTARTSYS;
break;
}
finish_wait(page_waitqueue(page), &wait.wait);
if (!ret)
err = -ETIMEDOUT;
if (!err)
SetPageUptodate(page);
if (err)
printk("%s: page: %p, uptodate: %d, locked: %d, err: %d.\n",
__func__, page, PageUptodate(page), PageLocked(page), err);
return err;
}
static int pohmelfs_read_page_complete(struct page **pages, unsigned int page_num,
void *private, int err)
{
struct page *page = private;
if (PageChecked(page))
return err;
if (err < 0) {
dprintk("%s: page: %p, err: %d.\n", __func__, page, err);
SetPageError(page);
}
unlock_page(page);
return err;
}
/*
* Read a page from remote server.
* Function will wait until page is unlocked.
*/
static int pohmelfs_readpage(struct file *file, struct page *page)
{
struct inode *inode = page->mapping->host;
struct pohmelfs_sb *psb = POHMELFS_SB(inode->i_sb);
struct pohmelfs_inode *pi = POHMELFS_I(inode);
struct netfs_trans *t;
struct netfs_cmd *cmd;
int err, path_len;
void *data;
u64 isize;
err = pohmelfs_data_lock(pi, page->index << PAGE_CACHE_SHIFT,
PAGE_SIZE, POHMELFS_READ_LOCK);
if (err)
goto err_out_exit;
isize = i_size_read(inode);
if (isize <= page->index << PAGE_CACHE_SHIFT) {
SetPageUptodate(page);
unlock_page(page);
return 0;
}
path_len = pohmelfs_path_length(pi);
if (path_len < 0) {
err = path_len;
goto err_out_exit;
}
t = netfs_trans_alloc(psb, path_len, NETFS_TRANS_SINGLE_DST, 0);
if (!t) {
err = -ENOMEM;
goto err_out_exit;
}
t->complete = pohmelfs_read_page_complete;
t->private = page;
cmd = netfs_trans_current(t);
data = (void *)(cmd + 1);
err = pohmelfs_construct_path_string(pi, data, path_len);
if (err < 0)
goto err_out_free;
path_len = err;
cmd->id = pi->ino;
cmd->start = page->index;
cmd->start <<= PAGE_CACHE_SHIFT;
cmd->size = PAGE_CACHE_SIZE + path_len;
cmd->cmd = NETFS_READ_PAGE;
cmd->ext = path_len;
dprintk("%s: path: '%s', page: %p, ino: %llu, start: %llu, size: %lu.\n",
__func__, (char *)data, page, pi->ino, cmd->start, PAGE_CACHE_SIZE);
netfs_convert_cmd(cmd);
netfs_trans_update(cmd, t, path_len);
err = netfs_trans_finish(t, psb);
if (err)
goto err_out_return;
return pohmelfs_wait_on_page_locked(page);
err_out_free:
t->result = err;
netfs_trans_put(t);
err_out_exit:
SetPageError(page);
if (PageLocked(page))
unlock_page(page);
err_out_return:
printk("%s: page: %p, start: %lu, size: %lu, err: %d.\n",
__func__, page, page->index << PAGE_CACHE_SHIFT, PAGE_CACHE_SIZE, err);
return err;
}
/*
* Write begin/end magic.
* Allocates a page and writes inode if it was not synced to server before.
*/
static int pohmelfs_write_begin(struct file *file, struct address_space *mapping,
loff_t pos, unsigned len, unsigned flags,
struct page **pagep, void **fsdata)
{
struct inode *inode = mapping->host;
struct page *page;
pgoff_t index;
unsigned start, end;
int err;
*pagep = NULL;
index = pos >> PAGE_CACHE_SHIFT;
start = pos & (PAGE_CACHE_SIZE - 1);
end = start + len;
page = grab_cache_page(mapping, index);
#if 0
dprintk("%s: page: %p pos: %llu, len: %u, index: %lu, start: %u, end: %u, uptodate: %d.\n",
__func__, page, pos, len, index, start, end, PageUptodate(page));
#endif
if (!page) {
err = -ENOMEM;
goto err_out_exit;
}
while (!PageUptodate(page)) {
if (start && test_bit(NETFS_INODE_REMOTE_SYNCED, &POHMELFS_I(inode)->state)) {
err = pohmelfs_readpage(file, page);
if (err)
goto err_out_exit;
lock_page(page);
continue;
}
if (len != PAGE_CACHE_SIZE) {
void *kaddr = kmap_atomic(page, KM_USER0);
memset(kaddr + start, 0, PAGE_CACHE_SIZE - start);
flush_dcache_page(page);
kunmap_atomic(kaddr, KM_USER0);
}
SetPageUptodate(page);
}
set_page_private(page, end);
*pagep = page;
return 0;
err_out_exit:
page_cache_release(page);
*pagep = NULL;
return err;
}
static int pohmelfs_write_end(struct file *file, struct address_space *mapping,
loff_t pos, unsigned len, unsigned copied,
struct page *page, void *fsdata)
{
struct inode *inode = mapping->host;
if (copied != len) {
unsigned from = pos & (PAGE_CACHE_SIZE - 1);
void *kaddr = kmap_atomic(page, KM_USER0);
memset(kaddr + from + copied, 0, len - copied);
flush_dcache_page(page);
kunmap_atomic(kaddr, KM_USER0);
}
SetPageUptodate(page);
set_page_dirty(page);
#if 0
dprintk("%s: page: %p [U: %d, D: %d, L: %d], pos: %llu, len: %u, copied: %u.\n",
__func__, page,
PageUptodate(page), PageDirty(page), PageLocked(page),
pos, len, copied);
#endif
flush_dcache_page(page);
unlock_page(page);
page_cache_release(page);
if (pos + copied > inode->i_size) {
struct pohmelfs_sb *psb = POHMELFS_SB(inode->i_sb);
psb->avail_size -= pos + copied - inode->i_size;
i_size_write(inode, pos + copied);
}
return copied;
}
static int pohmelfs_readpages_trans_complete(struct page **__pages, unsigned int page_num,
void *private, int err)
{
struct pohmelfs_inode *pi = private;
unsigned int i, num;
struct page **pages, *page = (struct page *)__pages;
loff_t index = page->index;
pages = kzalloc(sizeof(void *) * page_num, GFP_NOIO);
if (!pages)
return -ENOMEM;
num = find_get_pages_contig(pi->vfs_inode.i_mapping, index, page_num, pages);
if (num <= 0) {
err = num;
goto err_out_free;
}
for (i = 0; i < num; ++i) {
page = pages[i];
if (err)
printk("%s: %u/%u: page: %p, index: %lu, uptodate: %d, locked: %d, err: %d.\n",
__func__, i, num, page, page->index,
PageUptodate(page), PageLocked(page), err);
if (!PageChecked(page)) {
if (err < 0)
SetPageError(page);
unlock_page(page);
}
page_cache_release(page);
page_cache_release(page);
}
err_out_free:
kfree(pages);
return err;
}
static int pohmelfs_send_readpages(struct pohmelfs_inode *pi, struct page *first, unsigned int num)
{
struct netfs_trans *t;
struct netfs_cmd *cmd;
struct pohmelfs_sb *psb = POHMELFS_SB(pi->vfs_inode.i_sb);
int err, path_len;
void *data;
err = pohmelfs_data_lock(pi, first->index << PAGE_CACHE_SHIFT,
num * PAGE_SIZE, POHMELFS_READ_LOCK);
if (err)
goto err_out_exit;
path_len = pohmelfs_path_length(pi);
if (path_len < 0) {
err = path_len;
goto err_out_exit;
}
t = netfs_trans_alloc(psb, path_len, NETFS_TRANS_SINGLE_DST, 0);
if (!t) {
err = -ENOMEM;
goto err_out_exit;
}
cmd = netfs_trans_current(t);
data = (void *)(cmd + 1);
t->complete = pohmelfs_readpages_trans_complete;
t->private = pi;
t->page_num = num;
t->pages = (struct page **)first;
err = pohmelfs_construct_path_string(pi, data, path_len);
if (err < 0)
goto err_out_put;
path_len = err;
cmd->cmd = NETFS_READ_PAGES;
cmd->start = first->index;
cmd->start <<= PAGE_CACHE_SHIFT;
cmd->size = (num << 8 | PAGE_CACHE_SHIFT);
cmd->id = pi->ino;
cmd->ext = path_len;
dprintk("%s: t: %p, gen: %u, path: '%s', path_len: %u, "
"start: %lu, num: %u.\n",
__func__, t, t->gen, (char *)data, path_len,
first->index, num);
netfs_convert_cmd(cmd);
netfs_trans_update(cmd, t, path_len);
return netfs_trans_finish(t, psb);
err_out_put:
netfs_trans_free(t);
err_out_exit:
pohmelfs_readpages_trans_complete((struct page **)first, num, pi, err);
return err;
}
#define list_to_page(head) (list_entry((head)->prev, struct page, lru))
static int pohmelfs_readpages(struct file *file, struct address_space *mapping,
struct list_head *pages, unsigned nr_pages)
{
unsigned int page_idx, num = 0;
struct page *page = NULL, *first = NULL;
for (page_idx = 0; page_idx < nr_pages; page_idx++) {
page = list_to_page(pages);
prefetchw(&page->flags);
list_del(&page->lru);
if (!add_to_page_cache_lru(page, mapping,
page->index, GFP_KERNEL)) {
if (!num) {
num = 1;
first = page;
continue;
}
dprintk("%s: added to lru page: %p, page_index: %lu, first_index: %lu.\n",
__func__, page, page->index, first->index);
if (unlikely(first->index + num != page->index) || (num > 500)) {
pohmelfs_send_readpages(POHMELFS_I(mapping->host),
first, num);
first = page;
num = 0;
}
num++;
}
}
pohmelfs_send_readpages(POHMELFS_I(mapping->host), first, num);
/*
* This will be sync read, so when last page is processed,
* all previous are alerady unlocked and ready to be used.
*/
return 0;
}
/*
* Small addres space operations for POHMELFS.
*/
const struct address_space_operations pohmelfs_aops = {
.readpage = pohmelfs_readpage,
.readpages = pohmelfs_readpages,
.writepages = pohmelfs_writepages,
.write_begin = pohmelfs_write_begin,
.write_end = pohmelfs_write_end,
.set_page_dirty = __set_page_dirty_nobuffers,
};
/*
* ->detroy_inode() callback. Deletes inode from the caches
* and frees private data.
*/
static void pohmelfs_destroy_inode(struct inode *inode)
{
struct super_block *sb = inode->i_sb;
struct pohmelfs_sb *psb = POHMELFS_SB(sb);
struct pohmelfs_inode *pi = POHMELFS_I(inode);
/* pohmelfs_data_unlock(pi, 0, inode->i_size, POHMELFS_READ_LOCK); */
pohmelfs_inode_del_inode(psb, pi);
dprintk("%s: pi: %p, inode: %p, ino: %llu.\n",
__func__, pi, &pi->vfs_inode, pi->ino);
kmem_cache_free(pohmelfs_inode_cache, pi);
atomic_long_dec(&psb->total_inodes);
}
/*
* ->alloc_inode() callback. Allocates inode and initilizes private data.
*/
static struct inode *pohmelfs_alloc_inode(struct super_block *sb)
{
struct pohmelfs_inode *pi;
pi = kmem_cache_alloc(pohmelfs_inode_cache, GFP_NOIO);
if (!pi)
return NULL;
pi->hash_root = RB_ROOT;
mutex_init(&pi->offset_lock);
INIT_LIST_HEAD(&pi->sync_create_list);
INIT_LIST_HEAD(&pi->inode_entry);
pi->lock_type = 0;
pi->state = 0;
pi->total_len = 0;
pi->drop_count = 0;
dprintk("%s: pi: %p, inode: %p.\n", __func__, pi, &pi->vfs_inode);
atomic_long_inc(&POHMELFS_SB(sb)->total_inodes);
return &pi->vfs_inode;
}
/*
* We want fsync() to work on POHMELFS.
*/
static int pohmelfs_fsync(struct file *file, int datasync)
{
struct inode *inode = file->f_mapping->host;
struct writeback_control wbc = {
.sync_mode = WB_SYNC_ALL,
.nr_to_write = 0, /* sys_fsync did this */
};
return sync_inode(inode, &wbc);
}
ssize_t pohmelfs_write(struct file *file, const char __user *buf,
size_t len, loff_t *ppos)
{
struct address_space *mapping = file->f_mapping;
struct inode *inode = mapping->host;
struct pohmelfs_inode *pi = POHMELFS_I(inode);
struct iovec iov = { .iov_base = (void __user *)buf, .iov_len = len };
struct kiocb kiocb;
ssize_t ret;
loff_t pos = *ppos;
init_sync_kiocb(&kiocb, file);
kiocb.ki_pos = pos;
kiocb.ki_left = len;
dprintk("%s: len: %zu, pos: %llu.\n", __func__, len, pos);
mutex_lock(&inode->i_mutex);
ret = pohmelfs_data_lock(pi, pos, len, POHMELFS_WRITE_LOCK);
if (ret)
goto err_out_unlock;
ret = __generic_file_aio_write(&kiocb, &iov, 1, &kiocb.ki_pos);
*ppos = kiocb.ki_pos;
mutex_unlock(&inode->i_mutex);
WARN_ON(ret < 0);
if (ret > 0) {
ssize_t err;
err = generic_write_sync(file, pos, ret);
if (err < 0)
ret = err;
WARN_ON(ret < 0);
}
return ret;
err_out_unlock:
mutex_unlock(&inode->i_mutex);
return ret;
}
static const struct file_operations pohmelfs_file_ops = {
.open = generic_file_open,
.fsync = pohmelfs_fsync,
.llseek = generic_file_llseek,
.read = do_sync_read,
.aio_read = generic_file_aio_read,
.mmap = generic_file_mmap,
.splice_read = generic_file_splice_read,
.splice_write = generic_file_splice_write,
.write = pohmelfs_write,
.aio_write = generic_file_aio_write,
};
const struct inode_operations pohmelfs_symlink_inode_operations = {
.readlink = generic_readlink,
.follow_link = page_follow_link_light,
.put_link = page_put_link,
};
int pohmelfs_setattr_raw(struct inode *inode, struct iattr *attr)
{
int err;
err = inode_change_ok(inode, attr);
if (err) {
dprintk("%s: ino: %llu, inode changes are not allowed.\n", __func__, POHMELFS_I(inode)->ino);
goto err_out_exit;
}
if ((attr->ia_valid & ATTR_UID && attr->ia_uid != inode->i_uid) ||
(attr->ia_valid & ATTR_GID && attr->ia_gid != inode->i_gid)) {
err = dquot_transfer(inode, attr);
if (err)
goto err_out_exit;
}
err = inode_setattr(inode, attr);
if (err) {
dprintk("%s: ino: %llu, failed to set the attributes.\n", __func__, POHMELFS_I(inode)->ino);
goto err_out_exit;
}
dprintk("%s: ino: %llu, mode: %o -> %o, uid: %u -> %u, gid: %u -> %u, size: %llu -> %llu.\n",
__func__, POHMELFS_I(inode)->ino, inode->i_mode, attr->ia_mode,
inode->i_uid, attr->ia_uid, inode->i_gid, attr->ia_gid, inode->i_size, attr->ia_size);
return 0;
err_out_exit:
return err;
}
int pohmelfs_setattr(struct dentry *dentry, struct iattr *attr)
{
struct inode *inode = dentry->d_inode;
struct pohmelfs_inode *pi = POHMELFS_I(inode);
int err;
err = pohmelfs_data_lock(pi, 0, ~0, POHMELFS_WRITE_LOCK);
if (err)
goto err_out_exit;
err = security_inode_setattr(dentry, attr);
if (err)
goto err_out_exit;
err = pohmelfs_setattr_raw(inode, attr);
if (err)
goto err_out_exit;
return 0;
err_out_exit:
return err;
}
static int pohmelfs_send_xattr_req(struct pohmelfs_inode *pi, u64 id, u64 start,
const char *name, const void *value, size_t attrsize, int command)
{
struct pohmelfs_sb *psb = POHMELFS_SB(pi->vfs_inode.i_sb);
int err, path_len, namelen = strlen(name) + 1; /* 0-byte */
struct netfs_trans *t;
struct netfs_cmd *cmd;
void *data;
dprintk("%s: id: %llu, start: %llu, name: '%s', attrsize: %zu, cmd: %d.\n",
__func__, id, start, name, attrsize, command);
path_len = pohmelfs_path_length(pi);
if (path_len < 0) {
err = path_len;
goto err_out_exit;
}
t = netfs_trans_alloc(psb, namelen + path_len + attrsize, 0, 0);
if (!t) {
err = -ENOMEM;
goto err_out_exit;
}
cmd = netfs_trans_current(t);
data = cmd + 1;
path_len = pohmelfs_construct_path_string(pi, data, path_len);
if (path_len < 0) {
err = path_len;
goto err_out_put;
}
data += path_len;
/*
* 'name' is a NUL-terminated string already and
* 'namelen' includes 0-byte.
*/
memcpy(data, name, namelen);
data += namelen;
memcpy(data, value, attrsize);
cmd->cmd = command;
cmd->id = id;
cmd->start = start;
cmd->size = attrsize + namelen + path_len;
cmd->ext = path_len;
cmd->csize = 0;
cmd->cpad = 0;
netfs_convert_cmd(cmd);
netfs_trans_update(cmd, t, namelen + path_len + attrsize);
return netfs_trans_finish(t, psb);
err_out_put:
t->result = err;
netfs_trans_put(t);
err_out_exit:
return err;
}
static int pohmelfs_setxattr(struct dentry *dentry, const char *name,
const void *value, size_t attrsize, int flags)
{
struct inode *inode = dentry->d_inode;
struct pohmelfs_inode *pi = POHMELFS_I(inode);
struct pohmelfs_sb *psb = POHMELFS_SB(inode->i_sb);
if (!(psb->state_flags & POHMELFS_FLAGS_XATTR))
return -EOPNOTSUPP;
return pohmelfs_send_xattr_req(pi, flags, attrsize, name,
value, attrsize, NETFS_XATTR_SET);
}
static ssize_t pohmelfs_getxattr(struct dentry *dentry, const char *name,
void *value, size_t attrsize)
{
struct inode *inode = dentry->d_inode;
struct pohmelfs_inode *pi = POHMELFS_I(inode);
struct pohmelfs_sb *psb = POHMELFS_SB(inode->i_sb);
struct pohmelfs_mcache *m;
int err;
long timeout = psb->mcache_timeout;
if (!(psb->state_flags & POHMELFS_FLAGS_XATTR))
return -EOPNOTSUPP;
m = pohmelfs_mcache_alloc(psb, 0, attrsize, value);
if (IS_ERR(m))
return PTR_ERR(m);
dprintk("%s: ino: %llu, name: '%s', size: %zu.\n",
__func__, pi->ino, name, attrsize);
err = pohmelfs_send_xattr_req(pi, m->gen, attrsize, name, value, 0, NETFS_XATTR_GET);
if (err)
goto err_out_put;
do {
err = wait_for_completion_timeout(&m->complete, timeout);
if (err) {
err = m->err;
break;
}
/*
* This loop is a bit ugly, since it waits until reference counter
* hits 1 and then put object here. Main goal is to prevent race with
* network thread, when it can start processing given request, i.e.
* increase its reference counter but yet not complete it, while
* we will exit from ->getxattr() with timeout, and although request
* will not be freed (its reference counter was increased by network
* thread), data pointer provided by user may be released, so we will
* overwrite already freed area in network thread.
*
* Now after timeout we remove request from the cache, so it can not be
* found by network thread, and wait for its reference counter to hit 1,
* i.e. if network thread already started to process this request, we wait
* it to finish, and then free object locally. If reference counter is
* already 1, i.e. request is not used by anyone else, we can free it without
* problem.
*/
err = -ETIMEDOUT;
timeout = HZ;
pohmelfs_mcache_remove_locked(psb, m);
} while (atomic_read(&m->refcnt) != 1);
pohmelfs_mcache_put(psb, m);
dprintk("%s: ino: %llu, err: %d.\n", __func__, pi->ino, err);
return err;
err_out_put:
pohmelfs_mcache_put(psb, m);
return err;
}
static int pohmelfs_getattr(struct vfsmount *mnt, struct dentry *dentry, struct kstat *stat)
{
struct inode *inode = dentry->d_inode;
#if 0
struct pohmelfs_inode *pi = POHMELFS_I(inode);
int err;
err = pohmelfs_data_lock(pi, 0, ~0, POHMELFS_READ_LOCK);
if (err)
return err;
dprintk("%s: ino: %llu, mode: %o, uid: %u, gid: %u, size: %llu.\n",
__func__, pi->ino, inode->i_mode, inode->i_uid,
inode->i_gid, inode->i_size);
#endif
generic_fillattr(inode, stat);
return 0;
}
const struct inode_operations pohmelfs_file_inode_operations = {
.setattr = pohmelfs_setattr,
.getattr = pohmelfs_getattr,
.setxattr = pohmelfs_setxattr,
.getxattr = pohmelfs_getxattr,
};
/*
* Fill inode data: mode, size, operation callbacks and so on...
*/
void pohmelfs_fill_inode(struct inode *inode, struct netfs_inode_info *info)
{
inode->i_mode = info->mode;
inode->i_nlink = info->nlink;
inode->i_uid = info->uid;
inode->i_gid = info->gid;
inode->i_blocks = info->blocks;
inode->i_rdev = info->rdev;
inode->i_size = info->size;
inode->i_version = info->version;
inode->i_blkbits = ffs(info->blocksize);
dprintk("%s: inode: %p, num: %lu/%llu inode is regular: %d, dir: %d, link: %d, mode: %o, size: %llu.\n",
__func__, inode, inode->i_ino, info->ino,
S_ISREG(inode->i_mode), S_ISDIR(inode->i_mode),
S_ISLNK(inode->i_mode), inode->i_mode, inode->i_size);
inode->i_mtime = inode->i_atime = inode->i_ctime = CURRENT_TIME_SEC;
/*
* i_mapping is a pointer to i_data during inode initialization.
*/
inode->i_data.a_ops = &pohmelfs_aops;
if (S_ISREG(inode->i_mode)) {
inode->i_fop = &pohmelfs_file_ops;
inode->i_op = &pohmelfs_file_inode_operations;
} else if (S_ISDIR(inode->i_mode)) {
inode->i_fop = &pohmelfs_dir_fops;
inode->i_op = &pohmelfs_dir_inode_ops;
} else if (S_ISLNK(inode->i_mode)) {
inode->i_op = &pohmelfs_symlink_inode_operations;
inode->i_fop = &pohmelfs_file_ops;
} else {
inode->i_fop = &generic_ro_fops;
}
}
static void pohmelfs_drop_inode(struct inode *inode)
{
struct pohmelfs_sb *psb = POHMELFS_SB(inode->i_sb);
struct pohmelfs_inode *pi = POHMELFS_I(inode);
spin_lock(&psb->ino_lock);
list_del_init(&pi->inode_entry);
spin_unlock(&psb->ino_lock);
generic_drop_inode(inode);
}
static struct pohmelfs_inode *pohmelfs_get_inode_from_list(struct pohmelfs_sb *psb,
struct list_head *head, unsigned int *count)
{
struct pohmelfs_inode *pi = NULL;
spin_lock(&psb->ino_lock);
if (!list_empty(head)) {
pi = list_entry(head->next, struct pohmelfs_inode,
inode_entry);
list_del_init(&pi->inode_entry);
*count = pi->drop_count;
pi->drop_count = 0;
}
spin_unlock(&psb->ino_lock);
return pi;
}
static void pohmelfs_flush_transactions(struct pohmelfs_sb *psb)
{
struct pohmelfs_config *c;
mutex_lock(&psb->state_lock);
list_for_each_entry(c, &psb->state_list, config_entry) {
pohmelfs_state_flush_transactions(&c->state);
}
mutex_unlock(&psb->state_lock);
}
/*
* ->put_super() callback. Invoked before superblock is destroyed,
* so it has to clean all private data.
*/
static void pohmelfs_put_super(struct super_block *sb)
{
struct pohmelfs_sb *psb = POHMELFS_SB(sb);
struct pohmelfs_inode *pi;
unsigned int count;
unsigned int in_drop_list = 0;
struct inode *inode, *tmp;
dprintk("%s.\n", __func__);
/*
* Kill pending transactions, which could affect inodes in-flight.
*/
pohmelfs_flush_transactions(psb);
while ((pi = pohmelfs_get_inode_from_list(psb, &psb->drop_list, &count))) {
inode = &pi->vfs_inode;
dprintk("%s: ino: %llu, pi: %p, inode: %p, count: %u.\n",
__func__, pi->ino, pi, inode, count);
if (atomic_read(&inode->i_count) != count) {
printk("%s: ino: %llu, pi: %p, inode: %p, count: %u, i_count: %d.\n",
__func__, pi->ino, pi, inode, count,
atomic_read(&inode->i_count));
count = atomic_read(&inode->i_count);
in_drop_list++;
}
while (count--)
iput(&pi->vfs_inode);
}
list_for_each_entry_safe(inode, tmp, &sb->s_inodes, i_sb_list) {
pi = POHMELFS_I(inode);
dprintk("%s: ino: %llu, pi: %p, inode: %p, i_count: %u.\n",
__func__, pi->ino, pi, inode, atomic_read(&inode->i_count));
/*
* These are special inodes, they were created during
* directory reading or lookup, and were not bound to dentry,
* so they live here with reference counter being 1 and prevent
* umount from succeed since it believes that they are busy.
*/
count = atomic_read(&inode->i_count);
if (count) {
list_del_init(&inode->i_sb_list);
while (count--)
iput(&pi->vfs_inode);
}
}
psb->trans_scan_timeout = psb->drop_scan_timeout = 0;
cancel_rearming_delayed_work(&psb->dwork);
cancel_rearming_delayed_work(&psb->drop_dwork);
flush_scheduled_work();
dprintk("%s: stopped workqueues.\n", __func__);
pohmelfs_crypto_exit(psb);
pohmelfs_state_exit(psb);
bdi_destroy(&psb->bdi);
kfree(psb);
sb->s_fs_info = NULL;
}
static int pohmelfs_statfs(struct dentry *dentry, struct kstatfs *buf)
{
struct super_block *sb = dentry->d_sb;
struct pohmelfs_sb *psb = POHMELFS_SB(sb);
/*
* There are no filesystem size limits yet.
*/
memset(buf, 0, sizeof(struct kstatfs));
buf->f_type = POHMELFS_MAGIC_NUM; /* 'POH.' */
buf->f_bsize = sb->s_blocksize;
buf->f_files = psb->ino;
buf->f_namelen = 255;
buf->f_files = atomic_long_read(&psb->total_inodes);
buf->f_bfree = buf->f_bavail = psb->avail_size >> PAGE_SHIFT;
buf->f_blocks = psb->total_size >> PAGE_SHIFT;
dprintk("%s: total: %llu, avail: %llu, inodes: %llu, bsize: %lu.\n",
__func__, psb->total_size, psb->avail_size, buf->f_files, sb->s_blocksize);
return 0;
}
static int pohmelfs_show_options(struct seq_file *seq, struct vfsmount *vfs)
{
struct pohmelfs_sb *psb = POHMELFS_SB(vfs->mnt_sb);
seq_printf(seq, ",idx=%u", psb->idx);
seq_printf(seq, ",trans_scan_timeout=%u", jiffies_to_msecs(psb->trans_scan_timeout));
seq_printf(seq, ",drop_scan_timeout=%u", jiffies_to_msecs(psb->drop_scan_timeout));
seq_printf(seq, ",wait_on_page_timeout=%u", jiffies_to_msecs(psb->wait_on_page_timeout));
seq_printf(seq, ",trans_retries=%u", psb->trans_retries);
seq_printf(seq, ",crypto_thread_num=%u", psb->crypto_thread_num);
seq_printf(seq, ",trans_max_pages=%u", psb->trans_max_pages);
seq_printf(seq, ",mcache_timeout=%u", jiffies_to_msecs(psb->mcache_timeout));
if (psb->crypto_fail_unsupported)
seq_printf(seq, ",crypto_fail_unsupported");
return 0;
}
enum {
pohmelfs_opt_idx,
pohmelfs_opt_crypto_thread_num,
pohmelfs_opt_trans_max_pages,
pohmelfs_opt_crypto_fail_unsupported,
/* Remountable options */
pohmelfs_opt_trans_scan_timeout,
pohmelfs_opt_drop_scan_timeout,
pohmelfs_opt_wait_on_page_timeout,
pohmelfs_opt_trans_retries,
pohmelfs_opt_mcache_timeout,
};
static struct match_token pohmelfs_tokens[] = {
{pohmelfs_opt_idx, "idx=%u"},
{pohmelfs_opt_crypto_thread_num, "crypto_thread_num=%u"},
{pohmelfs_opt_trans_max_pages, "trans_max_pages=%u"},
{pohmelfs_opt_crypto_fail_unsupported, "crypto_fail_unsupported"},
{pohmelfs_opt_trans_scan_timeout, "trans_scan_timeout=%u"},
{pohmelfs_opt_drop_scan_timeout, "drop_scan_timeout=%u"},
{pohmelfs_opt_wait_on_page_timeout, "wait_on_page_timeout=%u"},
{pohmelfs_opt_trans_retries, "trans_retries=%u"},
{pohmelfs_opt_mcache_timeout, "mcache_timeout=%u"},
};
static int pohmelfs_parse_options(char *options, struct pohmelfs_sb *psb, int remount)
{
char *p;
substring_t args[MAX_OPT_ARGS];
int option, err;
if (!options)
return 0;
while ((p = strsep(&options, ",")) != NULL) {
int token;
if (!*p)
continue;
token = match_token(p, pohmelfs_tokens, args);
err = match_int(&args[0], &option);
if (err)
return err;
if (remount && token <= pohmelfs_opt_crypto_fail_unsupported)
continue;
switch (token) {
case pohmelfs_opt_idx:
psb->idx = option;
break;
case pohmelfs_opt_trans_scan_timeout:
psb->trans_scan_timeout = msecs_to_jiffies(option);
break;
case pohmelfs_opt_drop_scan_timeout:
psb->drop_scan_timeout = msecs_to_jiffies(option);
break;
case pohmelfs_opt_wait_on_page_timeout:
psb->wait_on_page_timeout = msecs_to_jiffies(option);
break;
case pohmelfs_opt_mcache_timeout:
psb->mcache_timeout = msecs_to_jiffies(option);
break;
case pohmelfs_opt_trans_retries:
psb->trans_retries = option;
break;
case pohmelfs_opt_crypto_thread_num:
psb->crypto_thread_num = option;
break;
case pohmelfs_opt_trans_max_pages:
psb->trans_max_pages = option;
break;
case pohmelfs_opt_crypto_fail_unsupported:
psb->crypto_fail_unsupported = 1;
break;
default:
return -EINVAL;
}
}
return 0;
}
static int pohmelfs_remount(struct super_block *sb, int *flags, char *data)
{
int err;
struct pohmelfs_sb *psb = POHMELFS_SB(sb);
unsigned long old_sb_flags = sb->s_flags;
err = pohmelfs_parse_options(data, psb, 1);
if (err)
goto err_out_restore;
if (!(*flags & MS_RDONLY))
sb->s_flags &= ~MS_RDONLY;
return 0;
err_out_restore:
sb->s_flags = old_sb_flags;
return err;
}
static void pohmelfs_flush_inode(struct pohmelfs_inode *pi, unsigned int count)
{
struct inode *inode = &pi->vfs_inode;
dprintk("%s: %p: ino: %llu, owned: %d.\n",
__func__, inode, pi->ino, test_bit(NETFS_INODE_OWNED, &pi->state));
mutex_lock(&inode->i_mutex);
if (test_and_clear_bit(NETFS_INODE_OWNED, &pi->state)) {
filemap_fdatawrite(inode->i_mapping);
inode->i_sb->s_op->write_inode(inode, 0);
}
#ifdef POHMELFS_TRUNCATE_ON_INODE_FLUSH
truncate_inode_pages(inode->i_mapping, 0);
#endif
pohmelfs_data_unlock(pi, 0, ~0, POHMELFS_WRITE_LOCK);
mutex_unlock(&inode->i_mutex);
}
static void pohmelfs_put_inode_count(struct pohmelfs_inode *pi, unsigned int count)
{
dprintk("%s: ino: %llu, pi: %p, inode: %p, count: %u.\n",
__func__, pi->ino, pi, &pi->vfs_inode, count);
if (test_and_clear_bit(NETFS_INODE_NEED_FLUSH, &pi->state))
pohmelfs_flush_inode(pi, count);
while (count--)
iput(&pi->vfs_inode);
}
static void pohmelfs_drop_scan(struct work_struct *work)
{
struct pohmelfs_sb *psb =
container_of(work, struct pohmelfs_sb, drop_dwork.work);
struct pohmelfs_inode *pi;
unsigned int count = 0;
while ((pi = pohmelfs_get_inode_from_list(psb, &psb->drop_list, &count)))
pohmelfs_put_inode_count(pi, count);
pohmelfs_check_states(psb);
if (psb->drop_scan_timeout)
schedule_delayed_work(&psb->drop_dwork, psb->drop_scan_timeout);
}
/*
* Run through all transactions starting from the oldest,
* drop transaction from current state and try to send it
* to all remote nodes, which are currently installed.
*/
static void pohmelfs_trans_scan_state(struct netfs_state *st)
{
struct rb_node *rb_node;
struct netfs_trans_dst *dst;
struct pohmelfs_sb *psb = st->psb;
unsigned int timeout = psb->trans_scan_timeout;
struct netfs_trans *t;
int err;
mutex_lock(&st->trans_lock);
for (rb_node = rb_first(&st->trans_root); rb_node; ) {
dst = rb_entry(rb_node, struct netfs_trans_dst, state_entry);
t = dst->trans;
if (timeout && time_after(dst->send_time + timeout, jiffies)
&& dst->retries == 0)
break;
dprintk("%s: t: %p, gen: %u, st: %p, retries: %u, max: %u.\n",
__func__, t, t->gen, st, dst->retries, psb->trans_retries);
netfs_trans_get(t);
rb_node = rb_next(rb_node);
err = -ETIMEDOUT;
if (timeout && (++dst->retries < psb->trans_retries))
err = netfs_trans_resend(t, psb);
if (err || (t->flags & NETFS_TRANS_SINGLE_DST)) {
if (netfs_trans_remove_nolock(dst, st))
netfs_trans_drop_dst_nostate(dst);
}
t->result = err;
netfs_trans_put(t);
}
mutex_unlock(&st->trans_lock);
}
/*
* Walk through all installed network states and resend all
* transactions, which are old enough.
*/
static void pohmelfs_trans_scan(struct work_struct *work)
{
struct pohmelfs_sb *psb =
container_of(work, struct pohmelfs_sb, dwork.work);
struct netfs_state *st;
struct pohmelfs_config *c;
mutex_lock(&psb->state_lock);
list_for_each_entry(c, &psb->state_list, config_entry) {
st = &c->state;
pohmelfs_trans_scan_state(st);
}
mutex_unlock(&psb->state_lock);
/*
* If no timeout specified then system is in the middle of umount process,
* so no need to reschedule scanning process again.
*/
if (psb->trans_scan_timeout)
schedule_delayed_work(&psb->dwork, psb->trans_scan_timeout);
}
int pohmelfs_meta_command_data(struct pohmelfs_inode *pi, u64 id, unsigned int cmd_op, char *addon,
unsigned int flags, netfs_trans_complete_t complete, void *priv, u64 start)
{
struct inode *inode = &pi->vfs_inode;
struct pohmelfs_sb *psb = POHMELFS_SB(inode->i_sb);
int err = 0, sz;
struct netfs_trans *t;
int path_len, addon_len = 0;
void *data;
struct netfs_inode_info *info;
struct netfs_cmd *cmd;
dprintk("%s: ino: %llu, cmd: %u, addon: %p.\n", __func__, pi->ino, cmd_op, addon);
path_len = pohmelfs_path_length(pi);
if (path_len < 0) {
err = path_len;
goto err_out_exit;
}
if (addon)
addon_len = strlen(addon) + 1; /* 0-byte */
sz = addon_len;
if (cmd_op == NETFS_INODE_INFO)
sz += sizeof(struct netfs_inode_info);
t = netfs_trans_alloc(psb, sz + path_len, flags, 0);
if (!t) {
err = -ENOMEM;
goto err_out_exit;
}
t->complete = complete;
t->private = priv;
cmd = netfs_trans_current(t);
data = (void *)(cmd + 1);
if (cmd_op == NETFS_INODE_INFO) {
info = (struct netfs_inode_info *)(cmd + 1);
data = (void *)(info + 1);
/*
* We are under i_mutex, can read and change whatever we want...
*/
info->mode = inode->i_mode;
info->nlink = inode->i_nlink;
info->uid = inode->i_uid;
info->gid = inode->i_gid;
info->blocks = inode->i_blocks;
info->rdev = inode->i_rdev;
info->size = inode->i_size;
info->version = inode->i_version;
netfs_convert_inode_info(info);
}
path_len = pohmelfs_construct_path_string(pi, data, path_len);
if (path_len < 0)
goto err_out_free;
dprintk("%s: path_len: %d.\n", __func__, path_len);
if (addon) {
path_len--; /* Do not place null-byte before the addon */
path_len += sprintf(data + path_len, "/%s", addon) + 1; /* 0 - byte */
}
sz += path_len;
cmd->cmd = cmd_op;
cmd->ext = path_len;
cmd->size = sz;
cmd->id = id;
cmd->start = start;
netfs_convert_cmd(cmd);
netfs_trans_update(cmd, t, sz);
/*
* Note, that it is possible to leak error here: transaction callback will not
* be invoked for allocation path failure.
*/
return netfs_trans_finish(t, psb);
err_out_free:
netfs_trans_free(t);
err_out_exit:
if (complete)
complete(NULL, 0, priv, err);
return err;
}
int pohmelfs_meta_command(struct pohmelfs_inode *pi, unsigned int cmd_op, unsigned int flags,
netfs_trans_complete_t complete, void *priv, u64 start)
{
return pohmelfs_meta_command_data(pi, pi->ino, cmd_op, NULL, flags, complete, priv, start);
}
/*
* Send request and wait for POHMELFS root capabilities response,
* which will update server's informaion about size of the export,
* permissions, number of objects, available size and so on.
*/
static int pohmelfs_root_handshake(struct pohmelfs_sb *psb)
{
struct netfs_trans *t;
struct netfs_cmd *cmd;
int err = -ENOMEM;
t = netfs_trans_alloc(psb, 0, 0, 0);
if (!t)
goto err_out_exit;
cmd = netfs_trans_current(t);
cmd->cmd = NETFS_CAPABILITIES;
cmd->id = POHMELFS_ROOT_CAPABILITIES;
cmd->size = 0;
cmd->start = 0;
cmd->ext = 0;
cmd->csize = 0;
netfs_convert_cmd(cmd);
netfs_trans_update(cmd, t, 0);
err = netfs_trans_finish(t, psb);
if (err)
goto err_out_exit;
psb->flags = ~0;
err = wait_event_interruptible_timeout(psb->wait,
(psb->flags != ~0),
psb->wait_on_page_timeout);
if (!err)
err = -ETIMEDOUT;
else if (err > 0)
err = -psb->flags;
if (err)
goto err_out_exit;
return 0;
err_out_exit:
return err;
}
static int pohmelfs_show_stats(struct seq_file *m, struct vfsmount *mnt)
{
struct netfs_state *st;
struct pohmelfs_ctl *ctl;
struct pohmelfs_sb *psb = POHMELFS_SB(mnt->mnt_sb);
struct pohmelfs_config *c;
mutex_lock(&psb->state_lock);
seq_printf(m, "\nidx addr(:port) socket_type protocol active priority permissions\n");
list_for_each_entry(c, &psb->state_list, config_entry) {
st = &c->state;
ctl = &st->ctl;
seq_printf(m, "%u ", ctl->idx);
if (ctl->addr.sa_family == AF_INET) {
struct sockaddr_in *sin = (struct sockaddr_in *)&st->ctl.addr;
seq_printf(m, "%pI4:%u", &sin->sin_addr.s_addr, ntohs(sin->sin_port));
} else if (ctl->addr.sa_family == AF_INET6) {
struct sockaddr_in6 *sin = (struct sockaddr_in6 *)&st->ctl.addr;
seq_printf(m, "%pi6:%u", &sin->sin6_addr, ntohs(sin->sin6_port));
} else {
unsigned int i;
for (i = 0; i < ctl->addrlen; ++i)
seq_printf(m, "%02x.", ctl->addr.addr[i]);
}
seq_printf(m, " %u %u %d %u %x\n",
ctl->type, ctl->proto,
st->socket != NULL,
ctl->prio, ctl->perm);
}
mutex_unlock(&psb->state_lock);
return 0;
}
static const struct super_operations pohmelfs_sb_ops = {
.alloc_inode = pohmelfs_alloc_inode,
.destroy_inode = pohmelfs_destroy_inode,
.drop_inode = pohmelfs_drop_inode,
.write_inode = pohmelfs_write_inode,
.put_super = pohmelfs_put_super,
.remount_fs = pohmelfs_remount,
.statfs = pohmelfs_statfs,
.show_options = pohmelfs_show_options,
.show_stats = pohmelfs_show_stats,
};
/*
* Allocate private superblock and create root dir.
*/
static int pohmelfs_fill_super(struct super_block *sb, void *data, int silent)
{
struct pohmelfs_sb *psb;
int err = -ENOMEM;
struct inode *root;
struct pohmelfs_inode *npi;
struct qstr str;
psb = kzalloc(sizeof(struct pohmelfs_sb), GFP_KERNEL);
if (!psb)
goto err_out_exit;
err = bdi_init(&psb->bdi);
if (err)
goto err_out_free_sb;
err = bdi_register(&psb->bdi, NULL, "pfs-%d", atomic_inc_return(&psb_bdi_num));
if (err) {
bdi_destroy(&psb->bdi);
goto err_out_free_sb;
}
sb->s_fs_info = psb;
sb->s_op = &pohmelfs_sb_ops;
sb->s_magic = POHMELFS_MAGIC_NUM;
sb->s_maxbytes = MAX_LFS_FILESIZE;
sb->s_blocksize = PAGE_SIZE;
sb->s_bdi = &psb->bdi;
psb->sb = sb;
psb->ino = 2;
psb->idx = 0;
psb->active_state = NULL;
psb->trans_retries = 5;
psb->trans_data_size = PAGE_SIZE;
psb->drop_scan_timeout = msecs_to_jiffies(1000);
psb->trans_scan_timeout = msecs_to_jiffies(5000);
psb->wait_on_page_timeout = msecs_to_jiffies(5000);
init_waitqueue_head(&psb->wait);
spin_lock_init(&psb->ino_lock);
INIT_LIST_HEAD(&psb->drop_list);
mutex_init(&psb->mcache_lock);
psb->mcache_root = RB_ROOT;
psb->mcache_timeout = msecs_to_jiffies(5000);
atomic_long_set(&psb->mcache_gen, 0);
psb->trans_max_pages = 100;
psb->crypto_align_size = 16;
psb->crypto_attached_size = 0;
psb->hash_strlen = 0;
psb->cipher_strlen = 0;
psb->perform_crypto = 0;
psb->crypto_thread_num = 2;
psb->crypto_fail_unsupported = 0;
mutex_init(&psb->crypto_thread_lock);
INIT_LIST_HEAD(&psb->crypto_ready_list);
INIT_LIST_HEAD(&psb->crypto_active_list);
atomic_set(&psb->trans_gen, 1);
atomic_long_set(&psb->total_inodes, 0);
mutex_init(&psb->state_lock);
INIT_LIST_HEAD(&psb->state_list);
err = pohmelfs_parse_options((char *) data, psb, 0);
if (err)
goto err_out_free_bdi;
err = pohmelfs_copy_crypto(psb);
if (err)
goto err_out_free_bdi;
err = pohmelfs_state_init(psb);
if (err)
goto err_out_free_strings;
err = pohmelfs_crypto_init(psb);
if (err)
goto err_out_state_exit;
err = pohmelfs_root_handshake(psb);
if (err)
goto err_out_crypto_exit;
str.name = "/";
str.hash = jhash("/", 1, 0);
str.len = 1;
npi = pohmelfs_create_entry_local(psb, NULL, &str, 0, 0755|S_IFDIR);
if (IS_ERR(npi)) {
err = PTR_ERR(npi);
goto err_out_crypto_exit;
}
set_bit(NETFS_INODE_REMOTE_SYNCED, &npi->state);
clear_bit(NETFS_INODE_OWNED, &npi->state);
root = &npi->vfs_inode;
sb->s_root = d_alloc_root(root);
if (!sb->s_root)
goto err_out_put_root;
INIT_DELAYED_WORK(&psb->drop_dwork, pohmelfs_drop_scan);
schedule_delayed_work(&psb->drop_dwork, psb->drop_scan_timeout);
INIT_DELAYED_WORK(&psb->dwork, pohmelfs_trans_scan);
schedule_delayed_work(&psb->dwork, psb->trans_scan_timeout);
return 0;
err_out_put_root:
iput(root);
err_out_crypto_exit:
pohmelfs_crypto_exit(psb);
err_out_state_exit:
pohmelfs_state_exit(psb);
err_out_free_strings:
kfree(psb->cipher_string);
kfree(psb->hash_string);
err_out_free_bdi:
bdi_destroy(&psb->bdi);
err_out_free_sb:
kfree(psb);
err_out_exit:
dprintk("%s: err: %d.\n", __func__, err);
return err;
}
/*
* Some VFS magic here...
*/
static int pohmelfs_get_sb(struct file_system_type *fs_type,
int flags, const char *dev_name, void *data, struct vfsmount *mnt)
{
return get_sb_nodev(fs_type, flags, data, pohmelfs_fill_super,
mnt);
}
/*
* We need this to sync all inodes earlier, since when writeback
* is invoked from the umount/mntput path dcache is already shrunk,
* see generic_shutdown_super(), and no inodes can access the path.
*/
static void pohmelfs_kill_super(struct super_block *sb)
{
sync_inodes_sb(sb);
kill_anon_super(sb);
}
static struct file_system_type pohmel_fs_type = {
.owner = THIS_MODULE,
.name = "pohmel",
.get_sb = pohmelfs_get_sb,
.kill_sb = pohmelfs_kill_super,
};
/*
* Cache and module initializations and freeing routings.
*/
static void pohmelfs_init_once(void *data)
{
struct pohmelfs_inode *pi = data;
inode_init_once(&pi->vfs_inode);
}
static int __init pohmelfs_init_inodecache(void)
{
pohmelfs_inode_cache = kmem_cache_create("pohmelfs_inode_cache",
sizeof(struct pohmelfs_inode),
0, (SLAB_RECLAIM_ACCOUNT|SLAB_MEM_SPREAD),
pohmelfs_init_once);
if (!pohmelfs_inode_cache)
return -ENOMEM;
return 0;
}
static void pohmelfs_destroy_inodecache(void)
{
kmem_cache_destroy(pohmelfs_inode_cache);
}
static int __init init_pohmel_fs(void)
{
int err;
err = pohmelfs_config_init();
if (err)
goto err_out_exit;
err = pohmelfs_init_inodecache();
if (err)
goto err_out_config_exit;
err = pohmelfs_mcache_init();
if (err)
goto err_out_destroy;
err = netfs_trans_init();
if (err)
goto err_out_mcache_exit;
err = register_filesystem(&pohmel_fs_type);
if (err)
goto err_out_trans;
return 0;
err_out_trans:
netfs_trans_exit();
err_out_mcache_exit:
pohmelfs_mcache_exit();
err_out_destroy:
pohmelfs_destroy_inodecache();
err_out_config_exit:
pohmelfs_config_exit();
err_out_exit:
return err;
}
static void __exit exit_pohmel_fs(void)
{
unregister_filesystem(&pohmel_fs_type);
pohmelfs_destroy_inodecache();
pohmelfs_mcache_exit();
pohmelfs_config_exit();
netfs_trans_exit();
}
module_init(init_pohmel_fs);
module_exit(exit_pohmel_fs);
MODULE_LICENSE("GPL");
MODULE_AUTHOR("Evgeniy Polyakov <zbr@ioremap.net>");
MODULE_DESCRIPTION("Pohmel filesystem");