| /* |
| * Copyright (C) 2005, 2006 |
| * Avishay Traeger (avishay@gmail.com) |
| * Copyright (C) 2008, 2009 |
| * Boaz Harrosh <bharrosh@panasas.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/writeback.h> |
| #include <linux/buffer_head.h> |
| #include <scsi/scsi_device.h> |
| |
| #include "exofs.h" |
| |
| #define EXOFS_DBGMSG2(M...) do {} while (0) |
| |
| enum { BIO_MAX_PAGES_KMALLOC = |
| (PAGE_SIZE - sizeof(struct bio)) / sizeof(struct bio_vec), |
| MAX_PAGES_KMALLOC = |
| PAGE_SIZE / sizeof(struct page *), |
| }; |
| |
| struct page_collect { |
| struct exofs_sb_info *sbi; |
| struct inode *inode; |
| unsigned expected_pages; |
| struct exofs_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 */ |
| }; |
| |
| 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; |
| } |
| |
| 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; |
| |
| /* 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 = MAX_PAGES_KMALLOC; |
| } |
| |
| static int pcol_try_alloc(struct page_collect *pcol) |
| { |
| unsigned pages = min_t(unsigned, pcol->expected_pages, |
| MAX_PAGES_KMALLOC); |
| |
| if (!pcol->ios) { /* First time allocate io_state */ |
| int ret = exofs_get_io_state(&pcol->sbi->layout, &pcol->ios); |
| |
| if (ret) |
| return ret; |
| } |
| |
| /* TODO: easily support bio chaining */ |
| pages = min_t(unsigned, pages, |
| pcol->sbi->layout.group_width * BIO_MAX_PAGES_KMALLOC); |
| |
| 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) { |
| exofs_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; |
| } |
| |
| static int update_read_page(struct page *page, int ret) |
| { |
| if (ret == 0) { |
| /* Everything is OK */ |
| SetPageUptodate(page); |
| if (PageError(page)) |
| ClearPageError(page); |
| } else if (ret == -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); |
| ret = 0; /* recovered error */ |
| EXOFS_DBGMSG("recovered read error\n"); |
| } else /* Error */ |
| SetPageError(page); |
| |
| return ret; |
| } |
| |
| static void update_write_page(struct page *page, int ret) |
| { |
| 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, bool do_unlock) |
| { |
| int i; |
| u64 resid; |
| u64 good_bytes; |
| u64 length = 0; |
| int ret = exofs_check_io(pcol->ios, &resid); |
| |
| if (likely(!ret)) |
| good_bytes = pcol->length; |
| else |
| good_bytes = pcol->length - resid; |
| |
| 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 (do_unlock) |
| 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 exofs_io_state *ios, void *p) |
| { |
| struct page_collect *pcol = p; |
| |
| __readpages_done(pcol, true); |
| 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 read_exec(struct page_collect *pcol, bool is_sync) |
| { |
| struct exofs_i_info *oi = exofs_i(pcol->inode); |
| struct exofs_io_state *ios = pcol->ios; |
| struct page_collect *pcol_copy = NULL; |
| int ret; |
| |
| if (!pcol->pages) |
| return 0; |
| |
| /* see comment in _readpage() about sync reads */ |
| WARN_ON(is_sync && (pcol->nr_pages != 1)); |
| |
| ios->pages = pcol->pages; |
| ios->nr_pages = pcol->nr_pages; |
| ios->length = pcol->length; |
| ios->offset = pcol->pg_first << PAGE_CACHE_SHIFT; |
| |
| if (is_sync) { |
| exofs_oi_read(oi, pcol->ios); |
| return __readpages_done(pcol, false); |
| } |
| |
| 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; |
| ret = exofs_oi_read(oi, ios); |
| if (unlikely(ret)) |
| goto err; |
| |
| atomic_inc(&pcol->sbi->s_curr_pending); |
| |
| EXOFS_DBGMSG2("read_exec obj=0x%llx start=0x%llx length=0x%lx\n", |
| ios->obj.id, _LLU(ios->offset), pcol->length); |
| |
| /* pages ownership was passed to pcol_copy */ |
| _pcol_reset(pcol); |
| return 0; |
| |
| err: |
| if (!is_sync) |
| _unlock_pcol_pages(pcol, ret, READ); |
| |
| pcol_free(pcol); |
| |
| 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; |
| |
| /* FIXME: Just for debugging, will be removed */ |
| if (PageUptodate(page)) |
| EXOFS_ERR("PageUptodate(0x%lx, 0x%lx)\n", pcol->inode->i_ino, |
| page->index); |
| |
| 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); |
| |
| unlock_page(page); |
| EXOFS_DBGMSG("readpage_strip(0x%lx, 0x%lx) empty page," |
| " splitting\n", inode->i_ino, page->index); |
| |
| return read_exec(pcol, false); |
| } |
| |
| 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, false); |
| 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, false); |
| 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; |
| } |
| |
| return read_exec(&pcol, false); |
| } |
| |
| static int _readpage(struct page *page, bool is_sync) |
| { |
| struct page_collect pcol; |
| int ret; |
| |
| _pcol_init(&pcol, 1, page->mapping->host); |
| |
| /* readpage_strip might call read_exec(,is_sync==false) at several |
| * places but not if we have a single page. |
| */ |
| ret = readpage_strip(&pcol, page); |
| if (ret) { |
| EXOFS_ERR("_readpage => %d\n", ret); |
| return ret; |
| } |
| |
| return read_exec(&pcol, is_sync); |
| } |
| |
| /* |
| * 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 exofs_io_state *ios, void *p) |
| { |
| struct page_collect *pcol = p; |
| int i; |
| u64 resid; |
| u64 good_bytes; |
| u64 length = 0; |
| int ret = exofs_check_io(ios, &resid); |
| |
| atomic_dec(&pcol->sbi->s_curr_pending); |
| |
| if (likely(!ret)) |
| good_bytes = pcol->length; |
| else |
| good_bytes = pcol->length - resid; |
| |
| 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 int write_exec(struct page_collect *pcol) |
| { |
| struct exofs_i_info *oi = exofs_i(pcol->inode); |
| struct exofs_io_state *ios = pcol->ios; |
| struct page_collect *pcol_copy = NULL; |
| int ret; |
| |
| if (!pcol->pages) |
| return 0; |
| |
| pcol_copy = kmalloc(sizeof(*pcol_copy), GFP_KERNEL); |
| if (!pcol_copy) { |
| EXOFS_ERR("write_exec: Faild to kmalloc(pcol)\n"); |
| ret = -ENOMEM; |
| goto err; |
| } |
| |
| *pcol_copy = *pcol; |
| |
| ios->pages = pcol_copy->pages; |
| ios->nr_pages = pcol_copy->nr_pages; |
| ios->offset = pcol_copy->pg_first << PAGE_CACHE_SHIFT; |
| ios->length = pcol_copy->length; |
| ios->done = writepages_done; |
| ios->private = pcol_copy; |
| |
| ret = exofs_oi_write(oi, ios); |
| if (unlikely(ret)) { |
| EXOFS_ERR("write_exec: exofs_oi_write() Faild\n"); |
| goto err; |
| } |
| |
| atomic_inc(&pcol->sbi->s_curr_pending); |
| EXOFS_DBGMSG2("write_exec(0x%lx, 0x%llx) start=0x%llx length=0x%lx\n", |
| pcol->inode->i_ino, pcol->pg_first, _LLU(ios->offset), |
| pcol->length); |
| /* pages ownership was passed to pcol_copy */ |
| _pcol_reset(pcol); |
| return 0; |
| |
| err: |
| _unlock_pcol_pages(pcol, ret, WRITE); |
| pcol_free(pcol); |
| 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 faild => %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 (ret) { |
| EXOFS_ERR("write_cache_pages => %d\n", ret); |
| return ret; |
| } |
| |
| return write_exec(&pcol); |
| } |
| |
| 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); |
| } |
| |
| 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 faild\n"); |
| return ret; |
| } |
| |
| page = *pagep; |
| } |
| |
| /* read modify write */ |
| if (!PageUptodate(page) && (len != PAGE_CACHE_SIZE)) { |
| ret = _readpage(page, true); |
| if (ret) { |
| /*SetPageError was done by _readpage. Is it ok?*/ |
| unlock_page(page); |
| EXOFS_DBGMSG("__readpage_filler faild\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; |
| /* 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 (i_size != inode->i_size) |
| mark_inode_dirty(inode); |
| return ret; |
| } |
| |
| const struct address_space_operations exofs_aops = { |
| .readpage = exofs_readpage, |
| .readpages = exofs_readpages, |
| .writepage = exofs_writepage, |
| .writepages = exofs_writepages, |
| .write_begin = exofs_write_begin_export, |
| .write_end = exofs_write_end, |
| }; |
| |
| /****************************************************************************** |
| * 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); |
| } |
| |
| /* |
| * get_block_t - Fill in a buffer_head |
| * An OSD takes care of block allocation so we just fake an allocation by |
| * putting in the inode's sector_t in the buffer_head. |
| * TODO: What about the case of create==0 and @iblock does not exist in the |
| * object? |
| */ |
| static int exofs_get_block(struct inode *inode, sector_t iblock, |
| struct buffer_head *bh_result, int create) |
| { |
| map_bh(bh_result, inode->i_sb, iblock); |
| return 0; |
| } |
| |
| const struct osd_attr g_attr_logical_length = ATTR_DEF( |
| OSD_APAGE_OBJECT_INFORMATION, OSD_ATTR_OI_LOGICAL_LENGTH, 8); |
| |
| static int _do_truncate(struct inode *inode) |
| { |
| struct exofs_i_info *oi = exofs_i(inode); |
| loff_t isize = i_size_read(inode); |
| int ret; |
| |
| inode->i_mtime = inode->i_ctime = CURRENT_TIME; |
| |
| nobh_truncate_page(inode->i_mapping, isize, exofs_get_block); |
| |
| ret = exofs_oi_truncate(oi, (u64)isize); |
| EXOFS_DBGMSG("(0x%lx) size=0x%llx\n", inode->i_ino, isize); |
| return ret; |
| } |
| |
| /* |
| * Truncate a file to the specified size - all we have to do is set the size |
| * attribute. We make sure the object exists first. |
| */ |
| void exofs_truncate(struct inode *inode) |
| { |
| struct exofs_i_info *oi = exofs_i(inode); |
| int ret; |
| |
| if (!(S_ISREG(inode->i_mode) || S_ISDIR(inode->i_mode) |
| || S_ISLNK(inode->i_mode))) |
| return; |
| if (exofs_inode_is_fast_symlink(inode)) |
| return; |
| if (IS_APPEND(inode) || IS_IMMUTABLE(inode)) |
| return; |
| |
| /* if we are about to truncate an object, and it hasn't been |
| * created yet, wait |
| */ |
| if (unlikely(wait_obj_created(oi))) |
| goto fail; |
| |
| ret = _do_truncate(inode); |
| if (ret) |
| goto fail; |
| |
| out: |
| mark_inode_dirty(inode); |
| return; |
| fail: |
| make_bad_inode(inode); |
| goto out; |
| } |
| |
| /* |
| * Set inode attributes - just call generic functions. |
| */ |
| int exofs_setattr(struct dentry *dentry, struct iattr *iattr) |
| { |
| struct inode *inode = dentry->d_inode; |
| int error; |
| |
| error = inode_change_ok(inode, iattr); |
| if (error) |
| return error; |
| |
| error = inode_setattr(inode, iattr); |
| return error; |
| } |
| |
| 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 exofs_io_state *ios; |
| struct exofs_on_disk_inode_layout *layout; |
| int ret; |
| |
| ret = exofs_get_io_state(&sbi->layout, &ios); |
| if (unlikely(ret)) { |
| EXOFS_ERR("%s: exofs_get_io_state failed.\n", __func__); |
| return ret; |
| } |
| |
| ios->obj.id = exofs_oi_objno(oi); |
| exofs_make_credential(oi->i_cred, &ios->obj); |
| ios->cred = oi->i_cred; |
| |
| attrs[1].len = exofs_on_disk_inode_layout_size(sbi->layout.s_numdevs); |
| attrs[2].len = exofs_on_disk_inode_layout_size(sbi->layout.s_numdevs); |
| |
| ios->in_attr = attrs; |
| ios->in_attr_len = ARRAY_SIZE(attrs); |
| |
| ret = exofs_sbi_read(ios); |
| if (unlikely(ret)) { |
| EXOFS_ERR("object(0x%llx) corrupted, return empty file=>%d\n", |
| _LLU(ios->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. |
| */ |
| if ((ret == -ENOENT) || (ret == -EINVAL)) |
| ret = 0; |
| goto out; |
| } |
| |
| ret = extract_attr_from_ios(ios, &attrs[0]); |
| if (ret) { |
| EXOFS_ERR("%s: extract_attr of inode_data 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 of inode_data 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 of inode_data 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: |
| exofs_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); |
| |
| /* 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); |
| inode->i_uid = le32_to_cpu(fcb.i_uid); |
| inode->i_gid = le32_to_cpu(fcb.i_gid); |
| inode->i_nlink = 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 = &exofs_fast_symlink_inode_operations; |
| else { |
| inode->i_op = &exofs_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)) { |
| BUG_ON(!obj_2bcreated(oi)); |
| wait_event(oi->i_wq, obj_created(oi)); |
| } |
| 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 exofs_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 = exofs_check_io(ios, NULL); |
| exofs_put_io_state(ios); |
| |
| atomic_dec(&sbi->s_curr_pending); |
| |
| if (unlikely(ret)) { |
| EXOFS_ERR("object=0x%llx creation faild in pid=0x%llx", |
| _LLU(exofs_oi_objno(oi)), _LLU(sbi->layout.s_pid)); |
| /*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); |
| |
| atomic_dec(&inode->i_count); |
| 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, int mode) |
| { |
| struct super_block *sb; |
| struct inode *inode; |
| struct exofs_i_info *oi; |
| struct exofs_sb_info *sbi; |
| struct exofs_io_state *ios; |
| int ret; |
| |
| sb = dir->i_sb; |
| inode = new_inode(sb); |
| if (!inode) |
| return ERR_PTR(-ENOMEM); |
| |
| oi = exofs_i(inode); |
| __oi_init(oi); |
| |
| set_obj_2bcreated(oi); |
| |
| sbi = sb->s_fs_info; |
| |
| sb->s_dirt = 1; |
| inode->i_uid = current->cred->fsuid; |
| if (dir->i_mode & S_ISGID) { |
| inode->i_gid = dir->i_gid; |
| if (S_ISDIR(mode)) |
| mode |= S_ISGID; |
| } else { |
| inode->i_gid = current->cred->fsgid; |
| } |
| inode->i_mode = 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); |
| |
| mark_inode_dirty(inode); |
| |
| ret = exofs_get_io_state(&sbi->layout, &ios); |
| if (unlikely(ret)) { |
| EXOFS_ERR("exofs_new_inode: exofs_get_io_state failed\n"); |
| return ERR_PTR(ret); |
| } |
| |
| ios->obj.id = exofs_oi_objno(oi); |
| exofs_make_credential(oi->i_cred, &ios->obj); |
| |
| /* increment the refcount so that the inode will still be around when we |
| * reach the callback |
| */ |
| atomic_inc(&inode->i_count); |
| |
| ios->done = create_done; |
| ios->private = inode; |
| ios->cred = oi->i_cred; |
| ret = exofs_sbi_create(ios); |
| if (ret) { |
| atomic_dec(&inode->i_count); |
| exofs_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 exofs_io_state *ios, void *p) |
| { |
| struct updatei_args *args = p; |
| |
| exofs_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 exofs_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("Faild kzalloc of args\n"); |
| return -ENOMEM; |
| } |
| |
| fcb = &args->fcb; |
| |
| fcb->i_mode = cpu_to_le16(inode->i_mode); |
| fcb->i_uid = cpu_to_le32(inode->i_uid); |
| fcb->i_gid = cpu_to_le32(inode->i_gid); |
| 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 = exofs_get_io_state(&sbi->layout, &ios); |
| if (unlikely(ret)) { |
| EXOFS_ERR("%s: exofs_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; |
| |
| 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"); |
| } |
| |
| if (!do_sync) { |
| args->sbi = sbi; |
| ios->done = updatei_done; |
| ios->private = args; |
| } |
| |
| ret = exofs_oi_write(oi, ios); |
| if (!do_sync && !ret) { |
| atomic_inc(&sbi->s_curr_pending); |
| goto out; /* deallocation in updatei_done */ |
| } |
| |
| exofs_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) |
| { |
| return exofs_update_inode(inode, wbc->sync_mode == WB_SYNC_ALL); |
| } |
| |
| /* |
| * Callback function from exofs_delete_inode() - don't have much cleaning up to |
| * do. |
| */ |
| static void delete_done(struct exofs_io_state *ios, void *p) |
| { |
| struct exofs_sb_info *sbi = p; |
| |
| exofs_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_delete_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 exofs_io_state *ios; |
| int ret; |
| |
| truncate_inode_pages(&inode->i_data, 0); |
| |
| if (is_bad_inode(inode)) |
| goto no_delete; |
| |
| mark_inode_dirty(inode); |
| exofs_update_inode(inode, inode_needs_sync(inode)); |
| |
| inode->i_size = 0; |
| if (inode->i_blocks) |
| exofs_truncate(inode); |
| |
| clear_inode(inode); |
| |
| ret = exofs_get_io_state(&sbi->layout, &ios); |
| if (unlikely(ret)) { |
| EXOFS_ERR("%s: exofs_get_io_state failed\n", __func__); |
| return; |
| } |
| |
| /* if we are deleting an obj that hasn't been created yet, wait */ |
| if (!obj_created(oi)) { |
| BUG_ON(!obj_2bcreated(oi)); |
| wait_event(oi->i_wq, obj_created(oi)); |
| } |
| |
| ios->obj.id = exofs_oi_objno(oi); |
| ios->done = delete_done; |
| ios->private = sbi; |
| ios->cred = oi->i_cred; |
| ret = exofs_sbi_remove(ios); |
| if (ret) { |
| EXOFS_ERR("%s: exofs_sbi_remove failed\n", __func__); |
| exofs_put_io_state(ios); |
| return; |
| } |
| atomic_inc(&sbi->s_curr_pending); |
| |
| return; |
| |
| no_delete: |
| clear_inode(inode); |
| } |