diff options
Diffstat (limited to 'fs/exofs/inode.c')
| -rw-r--r-- | fs/exofs/inode.c | 1514 |
1 files changed, 1514 insertions, 0 deletions
diff --git a/fs/exofs/inode.c b/fs/exofs/inode.c new file mode 100644 index 000000000..5f81fcd38 --- /dev/null +++ b/fs/exofs/inode.c @@ -0,0 +1,1514 @@ +/* + * 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_array(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_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_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_SIZE; + else if (page->index == end_index) + len = i_size & ~PAGE_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_SIZE) + zero_user(page, len, PAGE_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); + } + *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); + put_page(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_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_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_SIZE; + else { + len = i_size & ~PAGE_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); + mapping_set_error(page->mapping, -EIO); + 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_SHIFT; + end = (wbc->range_end == LLONG_MAX) ? + start + mapping->nrpages : + wbc->range_end >> PAGE_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) { + page = grab_cache_page_write_begin(mapping, pos >> PAGE_SHIFT, + flags); + if (!page) { + EXOFS_DBGMSG("grab_cache_page_write_begin failed\n"); + return -ENOMEM; + } + *pagep = page; + } + + /* read modify write */ + if (!PageUptodate(page) && (len != PAGE_SIZE)) { + loff_t i_size = i_size_read(mapping->host); + pgoff_t end_index = i_size >> PAGE_SHIFT; + + if (page->index > end_index) { + clear_highpage(page); + SetPageUptodate(page); + } else { + ret = _readpage(page, true); + if (ret) { + unlock_page(page); + EXOFS_DBGMSG("__readpage failed\n"); + } + } + } + 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; + loff_t last_pos = pos + copied; + + if (!PageUptodate(page)) { + if (copied < len) { + _write_failed(inode, pos + len); + copied = 0; + goto out; + } + SetPageUptodate(page); + } + if (last_pos > inode->i_size) { + i_size_write(inode, last_pos); + mark_inode_dirty(inode); + } + set_page_dirty(page); +out: + unlock_page(page); + put_page(page); + return copied; +} + +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) +{ + 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(inode); + + 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 = setattr_prepare(dentry, 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_nohighmem(inode); + 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(inode); + 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); +} |