diff options
Diffstat (limited to 'drivers/staging/pohmelfs/inode.c')
| -rw-r--r-- | drivers/staging/pohmelfs/inode.c | 2051 |
1 files changed, 2051 insertions, 0 deletions
diff --git a/drivers/staging/pohmelfs/inode.c b/drivers/staging/pohmelfs/inode.c new file mode 100644 index 000000000000..b2eaf9047266 --- /dev/null +++ b/drivers/staging/pohmelfs/inode.c @@ -0,0 +1,2051 @@ +/* + * 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; + +/* + * 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); + struct backing_dev_info *bdi = mapping->backing_dev_info; + 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->nonblocking && bdi_write_congested(bdi)) { + wbc->encountered_congestion = 1; + return 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; + if (wbc->nonblocking && bdi_write_congested(bdi)) { + wbc->encountered_congestion = 1; + 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_put; + } + 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, int sync) +{ + 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, struct dentry *dentry, 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_nolock(&kiocb, &iov, 1, pos); + *ppos = kiocb.ki_pos; + + mutex_unlock(&inode->i_mutex); + WARN_ON(ret < 0); + + if (ret > 0 && ((file->f_flags & O_SYNC) || IS_SYNC(inode))) { + ssize_t err; + + err = sync_page_range(inode, mapping, pos, ret); + if (err < 0) + ret = err; + WARN_ON(ret < 0); + } + + return ret; + +err_out_unlock: + mutex_unlock(&inode->i_mutex); + return ret; +} + +const static 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 = vfs_dq_transfer(inode, attr) ? -EDQUOT : 0; + 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); + + 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); + } + + truncate_inode_pages(inode->i_mapping, 0); + + 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 { + 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)); + seq_printf(m, "%u.%u.%u.%u:%u", NIPQUAD(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; + + 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; + + 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_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_sb; + + err = pohmelfs_copy_crypto(psb); + if (err) + goto err_out_free_sb; + + 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_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) +{ + struct writeback_control wbc = { + .sync_mode = WB_SYNC_ALL, + .range_start = 0, + .range_end = LLONG_MAX, + .nr_to_write = LONG_MAX, + }; + generic_sync_sb_inodes(sb, &wbc); + + 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"); |