/* * Copyright (C) 2005, 2006 * Avishay Traeger (avishay@gmail.com) * Copyright (C) 2008, 2009 * Boaz Harrosh <ooo@electrozaur.com> * * Copyrights for code taken from ext2: * Copyright (C) 1992, 1993, 1994, 1995 * Remy Card (card@masi.ibp.fr) * Laboratoire MASI - Institut Blaise Pascal * Universite Pierre et Marie Curie (Paris VI) * from * linux/fs/minix/inode.c * Copyright (C) 1991, 1992 Linus Torvalds * * This file is part of exofs. * * exofs 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. Since it is based on ext2, and the only * valid version of GPL for the Linux kernel is version 2, the only valid * version of GPL for exofs is version 2. * * exofs 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. * * You should have received a copy of the GNU General Public License * along with exofs; if not, write to the Free Software * Foundation, Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA */ #include <linux/slab.h> #include "exofs.h" #define EXOFS_DBGMSG2(M...) do {} while (0) unsigned exofs_max_io_pages(struct ore_layout *layout, unsigned expected_pages) { unsigned pages = min_t(unsigned, expected_pages, layout->max_io_length / PAGE_SIZE); return pages; } struct page_collect { struct exofs_sb_info *sbi; struct inode *inode; unsigned expected_pages; struct ore_io_state *ios; struct page **pages; unsigned alloc_pages; unsigned nr_pages; unsigned long length; loff_t pg_first; /* keep 64bit also in 32-arches */ bool read_4_write; /* This means two things: that the read is sync * And the pages should not be unlocked. */ struct page *that_locked_page; }; static void _pcol_init(struct page_collect *pcol, unsigned expected_pages, struct inode *inode) { struct exofs_sb_info *sbi = inode->i_sb->s_fs_info; pcol->sbi = sbi; pcol->inode = inode; pcol->expected_pages = expected_pages; pcol->ios = NULL; pcol->pages = NULL; pcol->alloc_pages = 0; pcol->nr_pages = 0; pcol->length = 0; pcol->pg_first = -1; pcol->read_4_write = false; pcol->that_locked_page = NULL; } static void _pcol_reset(struct page_collect *pcol) { pcol->expected_pages -= min(pcol->nr_pages, pcol->expected_pages); pcol->pages = NULL; pcol->alloc_pages = 0; pcol->nr_pages = 0; pcol->length = 0; pcol->pg_first = -1; pcol->ios = NULL; pcol->that_locked_page = NULL; /* this is probably the end of the loop but in writes * it might not end here. don't be left with nothing */ if (!pcol->expected_pages) pcol->expected_pages = exofs_max_io_pages(&pcol->sbi->layout, ~0); } static int pcol_try_alloc(struct page_collect *pcol) { unsigned pages; /* TODO: easily support bio chaining */ pages = exofs_max_io_pages(&pcol->sbi->layout, pcol->expected_pages); for (; pages; pages >>= 1) { pcol->pages = kmalloc(pages * sizeof(struct page *), GFP_KERNEL); if (likely(pcol->pages)) { pcol->alloc_pages = pages; return 0; } } EXOFS_ERR("Failed to kmalloc expected_pages=%u\n", pcol->expected_pages); return -ENOMEM; } static void pcol_free(struct page_collect *pcol) { kfree(pcol->pages); pcol->pages = NULL; if (pcol->ios) { ore_put_io_state(pcol->ios); pcol->ios = NULL; } } static int pcol_add_page(struct page_collect *pcol, struct page *page, unsigned len) { if (unlikely(pcol->nr_pages >= pcol->alloc_pages)) return -ENOMEM; pcol->pages[pcol->nr_pages++] = page; pcol->length += len; return 0; } enum {PAGE_WAS_NOT_IN_IO = 17}; static int update_read_page(struct page *page, int ret) { switch (ret) { case 0: /* Everything is OK */ SetPageUptodate(page); if (PageError(page)) ClearPageError(page); break; case -EFAULT: /* In this case we were trying to read something that wasn't on * disk yet - return a page full of zeroes. This should be OK, * because the object should be empty (if there was a write * before this read, the read would be waiting with the page * locked */ clear_highpage(page); SetPageUptodate(page); if (PageError(page)) ClearPageError(page); EXOFS_DBGMSG("recovered read error\n"); /* fall through */ case PAGE_WAS_NOT_IN_IO: ret = 0; /* recovered error */ break; default: SetPageError(page); } return ret; } static void update_write_page(struct page *page, int ret) { if (unlikely(ret == PAGE_WAS_NOT_IN_IO)) return; /* don't pass start don't collect $200 */ if (ret) { mapping_set_error(page->mapping, ret); SetPageError(page); } end_page_writeback(page); } /* Called at the end of reads, to optionally unlock pages and update their * status. */ static int __readpages_done(struct page_collect *pcol) { int i; u64 good_bytes; u64 length = 0; int ret = ore_check_io(pcol->ios, NULL); if (likely(!ret)) { good_bytes = pcol->length; ret = PAGE_WAS_NOT_IN_IO; } else { good_bytes = 0; } EXOFS_DBGMSG2("readpages_done(0x%lx) good_bytes=0x%llx" " length=0x%lx nr_pages=%u\n", pcol->inode->i_ino, _LLU(good_bytes), pcol->length, pcol->nr_pages); for (i = 0; i < pcol->nr_pages; i++) { struct page *page = pcol->pages[i]; struct inode *inode = page->mapping->host; int page_stat; if (inode != pcol->inode) continue; /* osd might add more pages at end */ if (likely(length < good_bytes)) page_stat = 0; else page_stat = ret; EXOFS_DBGMSG2(" readpages_done(0x%lx, 0x%lx) %s\n", inode->i_ino, page->index, page_stat ? "bad_bytes" : "good_bytes"); ret = update_read_page(page, page_stat); if (!pcol->read_4_write) unlock_page(page); length += PAGE_SIZE; } pcol_free(pcol); EXOFS_DBGMSG2("readpages_done END\n"); return ret; } /* callback of async reads */ static void readpages_done(struct ore_io_state *ios, void *p) { struct page_collect *pcol = p; __readpages_done(pcol); atomic_dec(&pcol->sbi->s_curr_pending); kfree(pcol); } static void _unlock_pcol_pages(struct page_collect *pcol, int ret, int rw) { int i; for (i = 0; i < pcol->nr_pages; i++) { struct page *page = pcol->pages[i]; if (rw == READ) update_read_page(page, ret); else update_write_page(page, ret); unlock_page(page); } } static int _maybe_not_all_in_one_io(struct ore_io_state *ios, struct page_collect *pcol_src, struct page_collect *pcol) { /* length was wrong or offset was not page aligned */ BUG_ON(pcol_src->nr_pages < ios->nr_pages); if (pcol_src->nr_pages > ios->nr_pages) { struct page **src_page; unsigned pages_less = pcol_src->nr_pages - ios->nr_pages; unsigned long len_less = pcol_src->length - ios->length; unsigned i; int ret; /* This IO was trimmed */ pcol_src->nr_pages = ios->nr_pages; pcol_src->length = ios->length; /* Left over pages are passed to the next io */ pcol->expected_pages += pages_less; pcol->nr_pages = pages_less; pcol->length = len_less; src_page = pcol_src->pages + pcol_src->nr_pages; pcol->pg_first = (*src_page)->index; ret = pcol_try_alloc(pcol); if (unlikely(ret)) return ret; for (i = 0; i < pages_less; ++i) pcol->pages[i] = *src_page++; EXOFS_DBGMSG("Length was adjusted nr_pages=0x%x " "pages_less=0x%x expected_pages=0x%x " "next_offset=0x%llx next_len=0x%lx\n", pcol_src->nr_pages, pages_less, pcol->expected_pages, pcol->pg_first * PAGE_SIZE, pcol->length); } return 0; } static int read_exec(struct page_collect *pcol) { struct exofs_i_info *oi = exofs_i(pcol->inode); struct ore_io_state *ios; struct page_collect *pcol_copy = NULL; int ret; if (!pcol->pages) return 0; if (!pcol->ios) { int ret = ore_get_rw_state(&pcol->sbi->layout, &oi->oc, true, pcol->pg_first << PAGE_CACHE_SHIFT, pcol->length, &pcol->ios); if (ret) return ret; } ios = pcol->ios; ios->pages = pcol->pages; if (pcol->read_4_write) { ore_read(pcol->ios); return __readpages_done(pcol); } pcol_copy = kmalloc(sizeof(*pcol_copy), GFP_KERNEL); if (!pcol_copy) { ret = -ENOMEM; goto err; } *pcol_copy = *pcol; ios->done = readpages_done; ios->private = pcol_copy; /* pages ownership was passed to pcol_copy */ _pcol_reset(pcol); ret = _maybe_not_all_in_one_io(ios, pcol_copy, pcol); if (unlikely(ret)) goto err; EXOFS_DBGMSG2("read_exec(0x%lx) offset=0x%llx length=0x%llx\n", pcol->inode->i_ino, _LLU(ios->offset), _LLU(ios->length)); ret = ore_read(ios); if (unlikely(ret)) goto err; atomic_inc(&pcol->sbi->s_curr_pending); return 0; err: if (!pcol_copy) /* Failed before ownership transfer */ pcol_copy = pcol; _unlock_pcol_pages(pcol_copy, ret, READ); pcol_free(pcol_copy); kfree(pcol_copy); return ret; } /* readpage_strip is called either directly from readpage() or by the VFS from * within read_cache_pages(), to add one more page to be read. It will try to * collect as many contiguous pages as posible. If a discontinuity is * encountered, or it runs out of resources, it will submit the previous segment * and will start a new collection. Eventually caller must submit the last * segment if present. */ static int readpage_strip(void *data, struct page *page) { struct page_collect *pcol = data; struct inode *inode = pcol->inode; struct exofs_i_info *oi = exofs_i(inode); loff_t i_size = i_size_read(inode); pgoff_t end_index = i_size >> PAGE_CACHE_SHIFT; size_t len; int ret; BUG_ON(!PageLocked(page)); /* FIXME: Just for debugging, will be removed */ if (PageUptodate(page)) EXOFS_ERR("PageUptodate(0x%lx, 0x%lx)\n", pcol->inode->i_ino, page->index); pcol->that_locked_page = page; if (page->index < end_index) len = PAGE_CACHE_SIZE; else if (page->index == end_index) len = i_size & ~PAGE_CACHE_MASK; else len = 0; if (!len || !obj_created(oi)) { /* this will be out of bounds, or doesn't exist yet. * Current page is cleared and the request is split */ clear_highpage(page); SetPageUptodate(page); if (PageError(page)) ClearPageError(page); if (!pcol->read_4_write) unlock_page(page); EXOFS_DBGMSG("readpage_strip(0x%lx) empty page len=%zx " "read_4_write=%d index=0x%lx end_index=0x%lx " "splitting\n", inode->i_ino, len, pcol->read_4_write, page->index, end_index); return read_exec(pcol); } try_again: if (unlikely(pcol->pg_first == -1)) { pcol->pg_first = page->index; } else if (unlikely((pcol->pg_first + pcol->nr_pages) != page->index)) { /* Discontinuity detected, split the request */ ret = read_exec(pcol); if (unlikely(ret)) goto fail; goto try_again; } if (!pcol->pages) { ret = pcol_try_alloc(pcol); if (unlikely(ret)) goto fail; } if (len != PAGE_CACHE_SIZE) zero_user(page, len, PAGE_CACHE_SIZE - len); EXOFS_DBGMSG2(" readpage_strip(0x%lx, 0x%lx) len=0x%zx\n", inode->i_ino, page->index, len); ret = pcol_add_page(pcol, page, len); if (ret) { EXOFS_DBGMSG2("Failed pcol_add_page pages[i]=%p " "this_len=0x%zx nr_pages=%u length=0x%lx\n", page, len, pcol->nr_pages, pcol->length); /* split the request, and start again with current page */ ret = read_exec(pcol); if (unlikely(ret)) goto fail; goto try_again; } return 0; fail: /* SetPageError(page); ??? */ unlock_page(page); return ret; } static int exofs_readpages(struct file *file, struct address_space *mapping, struct list_head *pages, unsigned nr_pages) { struct page_collect pcol; int ret; _pcol_init(&pcol, nr_pages, mapping->host); ret = read_cache_pages(mapping, pages, readpage_strip, &pcol); if (ret) { EXOFS_ERR("read_cache_pages => %d\n", ret); return ret; } ret = read_exec(&pcol); if (unlikely(ret)) return ret; return read_exec(&pcol); } static int _readpage(struct page *page, bool read_4_write) { struct page_collect pcol; int ret; _pcol_init(&pcol, 1, page->mapping->host); pcol.read_4_write = read_4_write; ret = readpage_strip(&pcol, page); if (ret) { EXOFS_ERR("_readpage => %d\n", ret); return ret; } return read_exec(&pcol); } /* * We don't need the file */ static int exofs_readpage(struct file *file, struct page *page) { return _readpage(page, false); } /* Callback for osd_write. All writes are asynchronous */ static void writepages_done(struct ore_io_state *ios, void *p) { struct page_collect *pcol = p; int i; u64 good_bytes; u64 length = 0; int ret = ore_check_io(ios, NULL); atomic_dec(&pcol->sbi->s_curr_pending); if (likely(!ret)) { good_bytes = pcol->length; ret = PAGE_WAS_NOT_IN_IO; } else { good_bytes = 0; } EXOFS_DBGMSG2("writepages_done(0x%lx) good_bytes=0x%llx" " length=0x%lx nr_pages=%u\n", pcol->inode->i_ino, _LLU(good_bytes), pcol->length, pcol->nr_pages); for (i = 0; i < pcol->nr_pages; i++) { struct page *page = pcol->pages[i]; struct inode *inode = page->mapping->host; int page_stat; if (inode != pcol->inode) continue; /* osd might add more pages to a bio */ if (likely(length < good_bytes)) page_stat = 0; else page_stat = ret; update_write_page(page, page_stat); unlock_page(page); EXOFS_DBGMSG2(" writepages_done(0x%lx, 0x%lx) status=%d\n", inode->i_ino, page->index, page_stat); length += PAGE_SIZE; } pcol_free(pcol); kfree(pcol); EXOFS_DBGMSG2("writepages_done END\n"); } static struct page *__r4w_get_page(void *priv, u64 offset, bool *uptodate) { struct page_collect *pcol = priv; pgoff_t index = offset / PAGE_SIZE; if (!pcol->that_locked_page || (pcol->that_locked_page->index != index)) { struct page *page; loff_t i_size = i_size_read(pcol->inode); if (offset >= i_size) { *uptodate = true; EXOFS_DBGMSG2("offset >= i_size index=0x%lx\n", index); return ZERO_PAGE(0); } page = find_get_page(pcol->inode->i_mapping, index); if (!page) { page = find_or_create_page(pcol->inode->i_mapping, index, GFP_NOFS); if (unlikely(!page)) { EXOFS_DBGMSG("grab_cache_page Failed " "index=0x%llx\n", _LLU(index)); return NULL; } unlock_page(page); } if (PageDirty(page) || PageWriteback(page)) *uptodate = true; else *uptodate = PageUptodate(page); EXOFS_DBGMSG2("index=0x%lx uptodate=%d\n", index, *uptodate); return page; } else { EXOFS_DBGMSG2("YES that_locked_page index=0x%lx\n", pcol->that_locked_page->index); *uptodate = true; return pcol->that_locked_page; } } static void __r4w_put_page(void *priv, struct page *page) { struct page_collect *pcol = priv; if ((pcol->that_locked_page != page) && (ZERO_PAGE(0) != page)) { EXOFS_DBGMSG2("index=0x%lx\n", page->index); page_cache_release(page); return; } EXOFS_DBGMSG2("that_locked_page index=0x%lx\n", ZERO_PAGE(0) == page ? -1 : page->index); } static const struct _ore_r4w_op _r4w_op = { .get_page = &__r4w_get_page, .put_page = &__r4w_put_page, }; static int write_exec(struct page_collect *pcol) { struct exofs_i_info *oi = exofs_i(pcol->inode); struct ore_io_state *ios; struct page_collect *pcol_copy = NULL; int ret; if (!pcol->pages) return 0; BUG_ON(pcol->ios); ret = ore_get_rw_state(&pcol->sbi->layout, &oi->oc, false, pcol->pg_first << PAGE_CACHE_SHIFT, pcol->length, &pcol->ios); if (unlikely(ret)) goto err; pcol_copy = kmalloc(sizeof(*pcol_copy), GFP_KERNEL); if (!pcol_copy) { EXOFS_ERR("write_exec: Failed to kmalloc(pcol)\n"); ret = -ENOMEM; goto err; } *pcol_copy = *pcol; ios = pcol->ios; ios->pages = pcol_copy->pages; ios->done = writepages_done; ios->r4w = &_r4w_op; ios->private = pcol_copy; /* pages ownership was passed to pcol_copy */ _pcol_reset(pcol); ret = _maybe_not_all_in_one_io(ios, pcol_copy, pcol); if (unlikely(ret)) goto err; EXOFS_DBGMSG2("write_exec(0x%lx) offset=0x%llx length=0x%llx\n", pcol->inode->i_ino, _LLU(ios->offset), _LLU(ios->length)); ret = ore_write(ios); if (unlikely(ret)) { EXOFS_ERR("write_exec: ore_write() Failed\n"); goto err; } atomic_inc(&pcol->sbi->s_curr_pending); return 0; err: if (!pcol_copy) /* Failed before ownership transfer */ pcol_copy = pcol; _unlock_pcol_pages(pcol_copy, ret, WRITE); pcol_free(pcol_copy); kfree(pcol_copy); return ret; } /* writepage_strip is called either directly from writepage() or by the VFS from * within write_cache_pages(), to add one more page to be written to storage. * It will try to collect as many contiguous pages as possible. If a * discontinuity is encountered or it runs out of resources it will submit the * previous segment and will start a new collection. * Eventually caller must submit the last segment if present. */ static int writepage_strip(struct page *page, struct writeback_control *wbc_unused, void *data) { struct page_collect *pcol = data; struct inode *inode = pcol->inode; struct exofs_i_info *oi = exofs_i(inode); loff_t i_size = i_size_read(inode); pgoff_t end_index = i_size >> PAGE_CACHE_SHIFT; size_t len; int ret; BUG_ON(!PageLocked(page)); ret = wait_obj_created(oi); if (unlikely(ret)) goto fail; if (page->index < end_index) /* in this case, the page is within the limits of the file */ len = PAGE_CACHE_SIZE; else { len = i_size & ~PAGE_CACHE_MASK; if (page->index > end_index || !len) { /* in this case, the page is outside the limits * (truncate in progress) */ ret = write_exec(pcol); if (unlikely(ret)) goto fail; if (PageError(page)) ClearPageError(page); unlock_page(page); EXOFS_DBGMSG("writepage_strip(0x%lx, 0x%lx) " "outside the limits\n", inode->i_ino, page->index); return 0; } } try_again: if (unlikely(pcol->pg_first == -1)) { pcol->pg_first = page->index; } else if (unlikely((pcol->pg_first + pcol->nr_pages) != page->index)) { /* Discontinuity detected, split the request */ ret = write_exec(pcol); if (unlikely(ret)) goto fail; EXOFS_DBGMSG("writepage_strip(0x%lx, 0x%lx) Discontinuity\n", inode->i_ino, page->index); goto try_again; } if (!pcol->pages) { ret = pcol_try_alloc(pcol); if (unlikely(ret)) goto fail; } EXOFS_DBGMSG2(" writepage_strip(0x%lx, 0x%lx) len=0x%zx\n", inode->i_ino, page->index, len); ret = pcol_add_page(pcol, page, len); if (unlikely(ret)) { EXOFS_DBGMSG2("Failed pcol_add_page " "nr_pages=%u total_length=0x%lx\n", pcol->nr_pages, pcol->length); /* split the request, next loop will start again */ ret = write_exec(pcol); if (unlikely(ret)) { EXOFS_DBGMSG("write_exec failed => %d", ret); goto fail; } goto try_again; } BUG_ON(PageWriteback(page)); set_page_writeback(page); return 0; fail: EXOFS_DBGMSG("Error: writepage_strip(0x%lx, 0x%lx)=>%d\n", inode->i_ino, page->index, ret); set_bit(AS_EIO, &page->mapping->flags); unlock_page(page); return ret; } static int exofs_writepages(struct address_space *mapping, struct writeback_control *wbc) { struct page_collect pcol; long start, end, expected_pages; int ret; start = wbc->range_start >> PAGE_CACHE_SHIFT; end = (wbc->range_end == LLONG_MAX) ? start + mapping->nrpages : wbc->range_end >> PAGE_CACHE_SHIFT; if (start || end) expected_pages = end - start + 1; else expected_pages = mapping->nrpages; if (expected_pages < 32L) expected_pages = 32L; EXOFS_DBGMSG2("inode(0x%lx) wbc->start=0x%llx wbc->end=0x%llx " "nrpages=%lu start=0x%lx end=0x%lx expected_pages=%ld\n", mapping->host->i_ino, wbc->range_start, wbc->range_end, mapping->nrpages, start, end, expected_pages); _pcol_init(&pcol, expected_pages, mapping->host); ret = write_cache_pages(mapping, wbc, writepage_strip, &pcol); if (unlikely(ret)) { EXOFS_ERR("write_cache_pages => %d\n", ret); return ret; } ret = write_exec(&pcol); if (unlikely(ret)) return ret; if (wbc->sync_mode == WB_SYNC_ALL) { return write_exec(&pcol); /* pump the last reminder */ } else if (pcol.nr_pages) { /* not SYNC let the reminder join the next writeout */ unsigned i; for (i = 0; i < pcol.nr_pages; i++) { struct page *page = pcol.pages[i]; end_page_writeback(page); set_page_dirty(page); unlock_page(page); } } return 0; } /* static int exofs_writepage(struct page *page, struct writeback_control *wbc) { struct page_collect pcol; int ret; _pcol_init(&pcol, 1, page->mapping->host); ret = writepage_strip(page, NULL, &pcol); if (ret) { EXOFS_ERR("exofs_writepage => %d\n", ret); return ret; } return write_exec(&pcol); } */ /* i_mutex held using inode->i_size directly */ static void _write_failed(struct inode *inode, loff_t to) { if (to > inode->i_size) truncate_pagecache(inode, inode->i_size); } int exofs_write_begin(struct file *file, struct address_space *mapping, loff_t pos, unsigned len, unsigned flags, struct page **pagep, void **fsdata) { int ret = 0; struct page *page; page = *pagep; if (page == NULL) { ret = simple_write_begin(file, mapping, pos, len, flags, pagep, fsdata); if (ret) { EXOFS_DBGMSG("simple_write_begin failed\n"); goto out; } page = *pagep; } /* read modify write */ if (!PageUptodate(page) && (len != PAGE_CACHE_SIZE)) { loff_t i_size = i_size_read(mapping->host); pgoff_t end_index = i_size >> PAGE_CACHE_SHIFT; size_t rlen; if (page->index < end_index) rlen = PAGE_CACHE_SIZE; else if (page->index == end_index) rlen = i_size & ~PAGE_CACHE_MASK; else rlen = 0; if (!rlen) { clear_highpage(page); SetPageUptodate(page); goto out; } ret = _readpage(page, true); if (ret) { /*SetPageError was done by _readpage. Is it ok?*/ unlock_page(page); EXOFS_DBGMSG("__readpage failed\n"); } } out: if (unlikely(ret)) _write_failed(mapping->host, pos + len); return ret; } static int exofs_write_begin_export(struct file *file, struct address_space *mapping, loff_t pos, unsigned len, unsigned flags, struct page **pagep, void **fsdata) { *pagep = NULL; return exofs_write_begin(file, mapping, pos, len, flags, pagep, fsdata); } static int exofs_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; /* According to comment in simple_write_end i_mutex is held */ loff_t i_size = inode->i_size; int ret; ret = simple_write_end(file, mapping,pos, len, copied, page, fsdata); if (unlikely(ret)) _write_failed(inode, pos + len); /* TODO: once simple_write_end marks inode dirty remove */ if (i_size != inode->i_size) mark_inode_dirty(inode); return ret; } static int exofs_releasepage(struct page *page, gfp_t gfp) { EXOFS_DBGMSG("page 0x%lx\n", page->index); WARN_ON(1); return 0; } static void exofs_invalidatepage(struct page *page, unsigned int offset, unsigned int length) { EXOFS_DBGMSG("page 0x%lx offset 0x%x length 0x%x\n", page->index, offset, length); WARN_ON(1); } /* TODO: Should be easy enough to do proprly */ static ssize_t exofs_direct_IO(struct kiocb *iocb, struct iov_iter *iter, loff_t offset) { return 0; } const struct address_space_operations exofs_aops = { .readpage = exofs_readpage, .readpages = exofs_readpages, .writepage = NULL, .writepages = exofs_writepages, .write_begin = exofs_write_begin_export, .write_end = exofs_write_end, .releasepage = exofs_releasepage, .set_page_dirty = __set_page_dirty_nobuffers, .invalidatepage = exofs_invalidatepage, /* Not implemented Yet */ .bmap = NULL, /* TODO: use osd's OSD_ACT_READ_MAP */ .direct_IO = exofs_direct_IO, /* With these NULL has special meaning or default is not exported */ .migratepage = NULL, .launder_page = NULL, .is_partially_uptodate = NULL, .error_remove_page = NULL, }; /****************************************************************************** * INODE OPERATIONS *****************************************************************************/ /* * Test whether an inode is a fast symlink. */ static inline int exofs_inode_is_fast_symlink(struct inode *inode) { struct exofs_i_info *oi = exofs_i(inode); return S_ISLNK(inode->i_mode) && (oi->i_data[0] != 0); } static int _do_truncate(struct inode *inode, loff_t newsize) { struct exofs_i_info *oi = exofs_i(inode); struct exofs_sb_info *sbi = inode->i_sb->s_fs_info; int ret; inode->i_mtime = inode->i_ctime = CURRENT_TIME; ret = ore_truncate(&sbi->layout, &oi->oc, (u64)newsize); if (likely(!ret)) truncate_setsize(inode, newsize); EXOFS_DBGMSG2("(0x%lx) size=0x%llx ret=>%d\n", inode->i_ino, newsize, ret); return ret; } /* * Set inode attributes - update size attribute on OSD if needed, * otherwise just call generic functions. */ int exofs_setattr(struct dentry *dentry, struct iattr *iattr) { struct inode *inode = d_inode(dentry); int error; /* if we are about to modify an object, and it hasn't been * created yet, wait */ error = wait_obj_created(exofs_i(inode)); if (unlikely(error)) return error; error = inode_change_ok(inode, iattr); if (unlikely(error)) return error; if ((iattr->ia_valid & ATTR_SIZE) && iattr->ia_size != i_size_read(inode)) { error = _do_truncate(inode, iattr->ia_size); if (unlikely(error)) return error; } setattr_copy(inode, iattr); mark_inode_dirty(inode); return 0; } static const struct osd_attr g_attr_inode_file_layout = ATTR_DEF( EXOFS_APAGE_FS_DATA, EXOFS_ATTR_INODE_FILE_LAYOUT, 0); static const struct osd_attr g_attr_inode_dir_layout = ATTR_DEF( EXOFS_APAGE_FS_DATA, EXOFS_ATTR_INODE_DIR_LAYOUT, 0); /* * Read the Linux inode info from the OSD, and return it as is. In exofs the * inode info is in an application specific page/attribute of the osd-object. */ static int exofs_get_inode(struct super_block *sb, struct exofs_i_info *oi, struct exofs_fcb *inode) { struct exofs_sb_info *sbi = sb->s_fs_info; struct osd_attr attrs[] = { [0] = g_attr_inode_data, [1] = g_attr_inode_file_layout, [2] = g_attr_inode_dir_layout, }; struct ore_io_state *ios; struct exofs_on_disk_inode_layout *layout; int ret; ret = ore_get_io_state(&sbi->layout, &oi->oc, &ios); if (unlikely(ret)) { EXOFS_ERR("%s: ore_get_io_state failed.\n", __func__); return ret; } attrs[1].len = exofs_on_disk_inode_layout_size(sbi->oc.numdevs); attrs[2].len = exofs_on_disk_inode_layout_size(sbi->oc.numdevs); ios->in_attr = attrs; ios->in_attr_len = ARRAY_SIZE(attrs); ret = ore_read(ios); if (unlikely(ret)) { EXOFS_ERR("object(0x%llx) corrupted, return empty file=>%d\n", _LLU(oi->one_comp.obj.id), ret); memset(inode, 0, sizeof(*inode)); inode->i_mode = 0040000 | (0777 & ~022); /* If object is lost on target we might as well enable it's * delete. */ ret = 0; goto out; } ret = extract_attr_from_ios(ios, &attrs[0]); if (ret) { EXOFS_ERR("%s: extract_attr 0 of inode failed\n", __func__); goto out; } WARN_ON(attrs[0].len != EXOFS_INO_ATTR_SIZE); memcpy(inode, attrs[0].val_ptr, EXOFS_INO_ATTR_SIZE); ret = extract_attr_from_ios(ios, &attrs[1]); if (ret) { EXOFS_ERR("%s: extract_attr 1 of inode failed\n", __func__); goto out; } if (attrs[1].len) { layout = attrs[1].val_ptr; if (layout->gen_func != cpu_to_le16(LAYOUT_MOVING_WINDOW)) { EXOFS_ERR("%s: unsupported files layout %d\n", __func__, layout->gen_func); ret = -ENOTSUPP; goto out; } } ret = extract_attr_from_ios(ios, &attrs[2]); if (ret) { EXOFS_ERR("%s: extract_attr 2 of inode failed\n", __func__); goto out; } if (attrs[2].len) { layout = attrs[2].val_ptr; if (layout->gen_func != cpu_to_le16(LAYOUT_MOVING_WINDOW)) { EXOFS_ERR("%s: unsupported meta-data layout %d\n", __func__, layout->gen_func); ret = -ENOTSUPP; goto out; } } out: ore_put_io_state(ios); return ret; } static void __oi_init(struct exofs_i_info *oi) { init_waitqueue_head(&oi->i_wq); oi->i_flags = 0; } /* * Fill in an inode read from the OSD and set it up for use */ struct inode *exofs_iget(struct super_block *sb, unsigned long ino) { struct exofs_i_info *oi; struct exofs_fcb fcb; struct inode *inode; int ret; inode = iget_locked(sb, ino); if (!inode) return ERR_PTR(-ENOMEM); if (!(inode->i_state & I_NEW)) return inode; oi = exofs_i(inode); __oi_init(oi); exofs_init_comps(&oi->oc, &oi->one_comp, sb->s_fs_info, exofs_oi_objno(oi)); /* read the inode from the osd */ ret = exofs_get_inode(sb, oi, &fcb); if (ret) goto bad_inode; set_obj_created(oi); /* copy stuff from on-disk struct to in-memory struct */ inode->i_mode = le16_to_cpu(fcb.i_mode); i_uid_write(inode, le32_to_cpu(fcb.i_uid)); i_gid_write(inode, le32_to_cpu(fcb.i_gid)); set_nlink(inode, le16_to_cpu(fcb.i_links_count)); inode->i_ctime.tv_sec = (signed)le32_to_cpu(fcb.i_ctime); inode->i_atime.tv_sec = (signed)le32_to_cpu(fcb.i_atime); inode->i_mtime.tv_sec = (signed)le32_to_cpu(fcb.i_mtime); inode->i_ctime.tv_nsec = inode->i_atime.tv_nsec = inode->i_mtime.tv_nsec = 0; oi->i_commit_size = le64_to_cpu(fcb.i_size); i_size_write(inode, oi->i_commit_size); inode->i_blkbits = EXOFS_BLKSHIFT; inode->i_generation = le32_to_cpu(fcb.i_generation); oi->i_dir_start_lookup = 0; if ((inode->i_nlink == 0) && (inode->i_mode == 0)) { ret = -ESTALE; goto bad_inode; } if (S_ISCHR(inode->i_mode) || S_ISBLK(inode->i_mode)) { if (fcb.i_data[0]) inode->i_rdev = old_decode_dev(le32_to_cpu(fcb.i_data[0])); else inode->i_rdev = new_decode_dev(le32_to_cpu(fcb.i_data[1])); } else { memcpy(oi->i_data, fcb.i_data, sizeof(fcb.i_data)); } if (S_ISREG(inode->i_mode)) { inode->i_op = &exofs_file_inode_operations; inode->i_fop = &exofs_file_operations; inode->i_mapping->a_ops = &exofs_aops; } else if (S_ISDIR(inode->i_mode)) { inode->i_op = &exofs_dir_inode_operations; inode->i_fop = &exofs_dir_operations; inode->i_mapping->a_ops = &exofs_aops; } else if (S_ISLNK(inode->i_mode)) { if (exofs_inode_is_fast_symlink(inode)) { inode->i_op = &simple_symlink_inode_operations; inode->i_link = (char *)oi->i_data; } else { inode->i_op = &page_symlink_inode_operations; inode->i_mapping->a_ops = &exofs_aops; } } else { inode->i_op = &exofs_special_inode_operations; if (fcb.i_data[0]) init_special_inode(inode, inode->i_mode, old_decode_dev(le32_to_cpu(fcb.i_data[0]))); else init_special_inode(inode, inode->i_mode, new_decode_dev(le32_to_cpu(fcb.i_data[1]))); } unlock_new_inode(inode); return inode; bad_inode: iget_failed(inode); return ERR_PTR(ret); } int __exofs_wait_obj_created(struct exofs_i_info *oi) { if (!obj_created(oi)) { EXOFS_DBGMSG("!obj_created\n"); BUG_ON(!obj_2bcreated(oi)); wait_event(oi->i_wq, obj_created(oi)); EXOFS_DBGMSG("wait_event done\n"); } return unlikely(is_bad_inode(&oi->vfs_inode)) ? -EIO : 0; } /* * Callback function from exofs_new_inode(). The important thing is that we * set the obj_created flag so that other methods know that the object exists on * the OSD. */ static void create_done(struct ore_io_state *ios, void *p) { struct inode *inode = p; struct exofs_i_info *oi = exofs_i(inode); struct exofs_sb_info *sbi = inode->i_sb->s_fs_info; int ret; ret = ore_check_io(ios, NULL); ore_put_io_state(ios); atomic_dec(&sbi->s_curr_pending); if (unlikely(ret)) { EXOFS_ERR("object=0x%llx creation failed in pid=0x%llx", _LLU(exofs_oi_objno(oi)), _LLU(oi->one_comp.obj.partition)); /*TODO: When FS is corrupted creation can fail, object already * exist. Get rid of this asynchronous creation, if exist * increment the obj counter and try the next object. Until we * succeed. All these dangling objects will be made into lost * files by chkfs.exofs */ } set_obj_created(oi); wake_up(&oi->i_wq); } /* * Set up a new inode and create an object for it on the OSD */ struct inode *exofs_new_inode(struct inode *dir, umode_t mode) { struct super_block *sb = dir->i_sb; struct exofs_sb_info *sbi = sb->s_fs_info; struct inode *inode; struct exofs_i_info *oi; struct ore_io_state *ios; int ret; inode = new_inode(sb); if (!inode) return ERR_PTR(-ENOMEM); oi = exofs_i(inode); __oi_init(oi); set_obj_2bcreated(oi); inode_init_owner(inode, dir, mode); inode->i_ino = sbi->s_nextid++; inode->i_blkbits = EXOFS_BLKSHIFT; inode->i_mtime = inode->i_atime = inode->i_ctime = CURRENT_TIME; oi->i_commit_size = inode->i_size = 0; spin_lock(&sbi->s_next_gen_lock); inode->i_generation = sbi->s_next_generation++; spin_unlock(&sbi->s_next_gen_lock); insert_inode_hash(inode); exofs_init_comps(&oi->oc, &oi->one_comp, sb->s_fs_info, exofs_oi_objno(oi)); exofs_sbi_write_stats(sbi); /* Make sure new sbi->s_nextid is on disk */ mark_inode_dirty(inode); ret = ore_get_io_state(&sbi->layout, &oi->oc, &ios); if (unlikely(ret)) { EXOFS_ERR("exofs_new_inode: ore_get_io_state failed\n"); return ERR_PTR(ret); } ios->done = create_done; ios->private = inode; ret = ore_create(ios); if (ret) { ore_put_io_state(ios); return ERR_PTR(ret); } atomic_inc(&sbi->s_curr_pending); return inode; } /* * struct to pass two arguments to update_inode's callback */ struct updatei_args { struct exofs_sb_info *sbi; struct exofs_fcb fcb; }; /* * Callback function from exofs_update_inode(). */ static void updatei_done(struct ore_io_state *ios, void *p) { struct updatei_args *args = p; ore_put_io_state(ios); atomic_dec(&args->sbi->s_curr_pending); kfree(args); } /* * Write the inode to the OSD. Just fill up the struct, and set the attribute * synchronously or asynchronously depending on the do_sync flag. */ static int exofs_update_inode(struct inode *inode, int do_sync) { struct exofs_i_info *oi = exofs_i(inode); struct super_block *sb = inode->i_sb; struct exofs_sb_info *sbi = sb->s_fs_info; struct ore_io_state *ios; struct osd_attr attr; struct exofs_fcb *fcb; struct updatei_args *args; int ret; args = kzalloc(sizeof(*args), GFP_KERNEL); if (!args) { EXOFS_DBGMSG("Failed kzalloc of args\n"); return -ENOMEM; } fcb = &args->fcb; fcb->i_mode = cpu_to_le16(inode->i_mode); fcb->i_uid = cpu_to_le32(i_uid_read(inode)); fcb->i_gid = cpu_to_le32(i_gid_read(inode)); fcb->i_links_count = cpu_to_le16(inode->i_nlink); fcb->i_ctime = cpu_to_le32(inode->i_ctime.tv_sec); fcb->i_atime = cpu_to_le32(inode->i_atime.tv_sec); fcb->i_mtime = cpu_to_le32(inode->i_mtime.tv_sec); oi->i_commit_size = i_size_read(inode); fcb->i_size = cpu_to_le64(oi->i_commit_size); fcb->i_generation = cpu_to_le32(inode->i_generation); if (S_ISCHR(inode->i_mode) || S_ISBLK(inode->i_mode)) { if (old_valid_dev(inode->i_rdev)) { fcb->i_data[0] = cpu_to_le32(old_encode_dev(inode->i_rdev)); fcb->i_data[1] = 0; } else { fcb->i_data[0] = 0; fcb->i_data[1] = cpu_to_le32(new_encode_dev(inode->i_rdev)); fcb->i_data[2] = 0; } } else memcpy(fcb->i_data, oi->i_data, sizeof(fcb->i_data)); ret = ore_get_io_state(&sbi->layout, &oi->oc, &ios); if (unlikely(ret)) { EXOFS_ERR("%s: ore_get_io_state failed.\n", __func__); goto free_args; } attr = g_attr_inode_data; attr.val_ptr = fcb; ios->out_attr_len = 1; ios->out_attr = &attr; wait_obj_created(oi); if (!do_sync) { args->sbi = sbi; ios->done = updatei_done; ios->private = args; } ret = ore_write(ios); if (!do_sync && !ret) { atomic_inc(&sbi->s_curr_pending); goto out; /* deallocation in updatei_done */ } ore_put_io_state(ios); free_args: kfree(args); out: EXOFS_DBGMSG("(0x%lx) do_sync=%d ret=>%d\n", inode->i_ino, do_sync, ret); return ret; } int exofs_write_inode(struct inode *inode, struct writeback_control *wbc) { /* FIXME: fix fsync and use wbc->sync_mode == WB_SYNC_ALL */ return exofs_update_inode(inode, 1); } /* * Callback function from exofs_delete_inode() - don't have much cleaning up to * do. */ static void delete_done(struct ore_io_state *ios, void *p) { struct exofs_sb_info *sbi = p; ore_put_io_state(ios); atomic_dec(&sbi->s_curr_pending); } /* * Called when the refcount of an inode reaches zero. We remove the object * from the OSD here. We make sure the object was created before we try and * delete it. */ void exofs_evict_inode(struct inode *inode) { struct exofs_i_info *oi = exofs_i(inode); struct super_block *sb = inode->i_sb; struct exofs_sb_info *sbi = sb->s_fs_info; struct ore_io_state *ios; int ret; truncate_inode_pages_final(&inode->i_data); /* TODO: should do better here */ if (inode->i_nlink || is_bad_inode(inode)) goto no_delete; inode->i_size = 0; clear_inode(inode); /* if we are deleting an obj that hasn't been created yet, wait. * This also makes sure that create_done cannot be called with an * already evicted inode. */ wait_obj_created(oi); /* ignore the error, attempt a remove anyway */ /* Now Remove the OSD objects */ ret = ore_get_io_state(&sbi->layout, &oi->oc, &ios); if (unlikely(ret)) { EXOFS_ERR("%s: ore_get_io_state failed\n", __func__); return; } ios->done = delete_done; ios->private = sbi; ret = ore_remove(ios); if (ret) { EXOFS_ERR("%s: ore_remove failed\n", __func__); ore_put_io_state(ios); return; } atomic_inc(&sbi->s_curr_pending); return; no_delete: clear_inode(inode); }