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-rw-r--r--fs/exofs/inode.c1303
1 files changed, 1303 insertions, 0 deletions
diff --git a/fs/exofs/inode.c b/fs/exofs/inode.c
new file mode 100644
index 00000000000..ba8d9fab469
--- /dev/null
+++ b/fs/exofs/inode.c
@@ -0,0 +1,1303 @@
+/*
+ * Copyright (C) 2005, 2006
+ * Avishay Traeger (avishay@gmail.com) (avishay@il.ibm.com)
+ * Copyright (C) 2005, 2006
+ * International Business Machines
+ * 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"
+
+#ifdef CONFIG_EXOFS_DEBUG
+# define EXOFS_DEBUG_OBJ_ISIZE 1
+#endif
+
+struct page_collect {
+ struct exofs_sb_info *sbi;
+ struct request_queue *req_q;
+ struct inode *inode;
+ unsigned expected_pages;
+
+ struct bio *bio;
+ 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;
+ struct request_queue *req_q = sbi->s_dev->scsi_device->request_queue;
+
+ pcol->sbi = sbi;
+ pcol->req_q = req_q;
+ pcol->inode = inode;
+ pcol->expected_pages = expected_pages;
+
+ pcol->bio = NULL;
+ pcol->nr_pages = 0;
+ pcol->length = 0;
+ pcol->pg_first = -1;
+
+ EXOFS_DBGMSG("_pcol_init ino=0x%lx expected_pages=%u\n", inode->i_ino,
+ expected_pages);
+}
+
+static void _pcol_reset(struct page_collect *pcol)
+{
+ pcol->expected_pages -= min(pcol->nr_pages, pcol->expected_pages);
+
+ pcol->bio = NULL;
+ pcol->nr_pages = 0;
+ pcol->length = 0;
+ pcol->pg_first = -1;
+ EXOFS_DBGMSG("_pcol_reset ino=0x%lx expected_pages=%u\n",
+ pcol->inode->i_ino, pcol->expected_pages);
+
+ /* 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 = 128;
+}
+
+static int pcol_try_alloc(struct page_collect *pcol)
+{
+ int pages = min_t(unsigned, pcol->expected_pages, BIO_MAX_PAGES);
+
+ for (; pages; pages >>= 1) {
+ pcol->bio = bio_alloc(GFP_KERNEL, pages);
+ if (likely(pcol->bio))
+ return 0;
+ }
+
+ EXOFS_ERR("Failed to kcalloc expected_pages=%u\n",
+ pcol->expected_pages);
+ return -ENOMEM;
+}
+
+static void pcol_free(struct page_collect *pcol)
+{
+ bio_put(pcol->bio);
+ pcol->bio = NULL;
+}
+
+static int pcol_add_page(struct page_collect *pcol, struct page *page,
+ unsigned len)
+{
+ int added_len = bio_add_pc_page(pcol->req_q, pcol->bio, page, len, 0);
+ if (unlikely(len != added_len))
+ return -ENOMEM;
+
+ ++pcol->nr_pages;
+ 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 osd_request *or, struct page_collect *pcol,
+ bool do_unlock)
+{
+ struct bio_vec *bvec;
+ int i;
+ u64 resid;
+ u64 good_bytes;
+ u64 length = 0;
+ int ret = exofs_check_ok_resid(or, &resid, NULL);
+
+ osd_end_request(or);
+
+ if (likely(!ret))
+ good_bytes = pcol->length;
+ else if (!resid)
+ good_bytes = 0;
+ else
+ good_bytes = pcol->length - resid;
+
+ EXOFS_DBGMSG("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);
+
+ __bio_for_each_segment(bvec, pcol->bio, i, 0) {
+ struct page *page = bvec->bv_page;
+ 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_DBGMSG(" 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 += bvec->bv_len;
+ }
+
+ pcol_free(pcol);
+ EXOFS_DBGMSG("readpages_done END\n");
+ return ret;
+}
+
+/* callback of async reads */
+static void readpages_done(struct osd_request *or, void *p)
+{
+ struct page_collect *pcol = p;
+
+ __readpages_done(or, pcol, true);
+ atomic_dec(&pcol->sbi->s_curr_pending);
+ kfree(p);
+}
+
+static void _unlock_pcol_pages(struct page_collect *pcol, int ret, int rw)
+{
+ struct bio_vec *bvec;
+ int i;
+
+ __bio_for_each_segment(bvec, pcol->bio, i, 0) {
+ struct page *page = bvec->bv_page;
+
+ if (rw == READ)
+ update_read_page(page, ret);
+ else
+ update_write_page(page, ret);
+
+ unlock_page(page);
+ }
+ pcol_free(pcol);
+}
+
+static int read_exec(struct page_collect *pcol, bool is_sync)
+{
+ struct exofs_i_info *oi = exofs_i(pcol->inode);
+ struct osd_obj_id obj = {pcol->sbi->s_pid,
+ pcol->inode->i_ino + EXOFS_OBJ_OFF};
+ struct osd_request *or = NULL;
+ struct page_collect *pcol_copy = NULL;
+ loff_t i_start = pcol->pg_first << PAGE_CACHE_SHIFT;
+ int ret;
+
+ if (!pcol->bio)
+ return 0;
+
+ /* see comment in _readpage() about sync reads */
+ WARN_ON(is_sync && (pcol->nr_pages != 1));
+
+ or = osd_start_request(pcol->sbi->s_dev, GFP_KERNEL);
+ if (unlikely(!or)) {
+ ret = -ENOMEM;
+ goto err;
+ }
+
+ osd_req_read(or, &obj, pcol->bio, i_start);
+
+ if (is_sync) {
+ exofs_sync_op(or, pcol->sbi->s_timeout, oi->i_cred);
+ return __readpages_done(or, pcol, false);
+ }
+
+ pcol_copy = kmalloc(sizeof(*pcol_copy), GFP_KERNEL);
+ if (!pcol_copy) {
+ ret = -ENOMEM;
+ goto err;
+ }
+
+ *pcol_copy = *pcol;
+ ret = exofs_async_op(or, readpages_done, pcol_copy, oi->i_cred);
+ if (unlikely(ret))
+ goto err;
+
+ atomic_inc(&pcol->sbi->s_curr_pending);
+
+ EXOFS_DBGMSG("read_exec obj=0x%llx start=0x%llx length=0x%lx\n",
+ obj.id, _LLU(i_start), pcol->length);
+
+ /* pages ownership was passed to pcol_copy */
+ _pcol_reset(pcol);
+ return 0;
+
+err:
+ if (!is_sync)
+ _unlock_pcol_pages(pcol, ret, READ);
+ kfree(pcol_copy);
+ if (or)
+ osd_end_request(or);
+ 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->bio) {
+ ret = pcol_try_alloc(pcol);
+ if (unlikely(ret))
+ goto fail;
+ }
+
+ if (len != PAGE_CACHE_SIZE)
+ zero_user(page, len, PAGE_CACHE_SIZE - len);
+
+ EXOFS_DBGMSG(" 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_DBGMSG("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(,async) inside at several places
+ * but this is safe for is_async=0 since read_exec will not do anything
+ * when 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 asynchronouse */
+static void writepages_done(struct osd_request *or, void *p)
+{
+ struct page_collect *pcol = p;
+ struct bio_vec *bvec;
+ int i;
+ u64 resid;
+ u64 good_bytes;
+ u64 length = 0;
+
+ int ret = exofs_check_ok_resid(or, NULL, &resid);
+
+ osd_end_request(or);
+ atomic_dec(&pcol->sbi->s_curr_pending);
+
+ if (likely(!ret))
+ good_bytes = pcol->length;
+ else if (!resid)
+ good_bytes = 0;
+ else
+ good_bytes = pcol->length - resid;
+
+ EXOFS_DBGMSG("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);
+
+ __bio_for_each_segment(bvec, pcol->bio, i, 0) {
+ struct page *page = bvec->bv_page;
+ 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_DBGMSG(" writepages_done(0x%lx, 0x%lx) status=%d\n",
+ inode->i_ino, page->index, page_stat);
+
+ length += bvec->bv_len;
+ }
+
+ pcol_free(pcol);
+ kfree(pcol);
+ EXOFS_DBGMSG("writepages_done END\n");
+}
+
+static int write_exec(struct page_collect *pcol)
+{
+ struct exofs_i_info *oi = exofs_i(pcol->inode);
+ struct osd_obj_id obj = {pcol->sbi->s_pid,
+ pcol->inode->i_ino + EXOFS_OBJ_OFF};
+ struct osd_request *or = NULL;
+ struct page_collect *pcol_copy = NULL;
+ loff_t i_start = pcol->pg_first << PAGE_CACHE_SHIFT;
+ int ret;
+
+ if (!pcol->bio)
+ return 0;
+
+ or = osd_start_request(pcol->sbi->s_dev, GFP_KERNEL);
+ if (unlikely(!or)) {
+ EXOFS_ERR("write_exec: Faild to osd_start_request()\n");
+ ret = -ENOMEM;
+ goto err;
+ }
+
+ 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;
+
+ osd_req_write(or, &obj, pcol_copy->bio, i_start);
+ ret = exofs_async_op(or, writepages_done, pcol_copy, oi->i_cred);
+ if (unlikely(ret)) {
+ EXOFS_ERR("write_exec: exofs_async_op() Faild\n");
+ goto err;
+ }
+
+ atomic_inc(&pcol->sbi->s_curr_pending);
+ EXOFS_DBGMSG("write_exec(0x%lx, 0x%llx) start=0x%llx length=0x%lx\n",
+ pcol->inode->i_ino, pcol->pg_first, _LLU(i_start),
+ pcol->length);
+ /* pages ownership was passed to pcol_copy */
+ _pcol_reset(pcol);
+ return 0;
+
+err:
+ _unlock_pcol_pages(pcol, ret, WRITE);
+ kfree(pcol_copy);
+ if (or)
+ osd_end_request(or);
+ 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);
+ 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;
+ goto try_again;
+ }
+
+ if (!pcol->bio) {
+ ret = pcol_try_alloc(pcol);
+ if (unlikely(ret))
+ goto fail;
+ }
+
+ EXOFS_DBGMSG(" 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_DBGMSG("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:
+ 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 = min(end - start + 1, 32L);
+ else
+ expected_pages = mapping->nrpages;
+
+ EXOFS_DBGMSG("inode(0x%lx) wbc->start=0x%llx wbc->end=0x%llx"
+ " m->nrpages=%lu start=0x%lx end=0x%lx\n",
+ mapping->host->i_ino, wbc->range_start, wbc->range_end,
+ mapping->nrpages, start, end);
+
+ _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);
+}
+
+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 = simple_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);
+
+/*
+ * 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_sb_info *sbi = inode->i_sb->s_fs_info;
+ struct exofs_i_info *oi = exofs_i(inode);
+ struct osd_obj_id obj = {sbi->s_pid, inode->i_ino + EXOFS_OBJ_OFF};
+ struct osd_request *or;
+ struct osd_attr attr;
+ loff_t isize = i_size_read(inode);
+ __be64 newsize;
+ 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;
+ inode->i_mtime = inode->i_ctime = CURRENT_TIME;
+
+ nobh_truncate_page(inode->i_mapping, isize, exofs_get_block);
+
+ or = osd_start_request(sbi->s_dev, GFP_KERNEL);
+ if (unlikely(!or)) {
+ EXOFS_ERR("ERROR: exofs_truncate: osd_start_request failed\n");
+ goto fail;
+ }
+
+ osd_req_set_attributes(or, &obj);
+
+ newsize = cpu_to_be64((u64)isize);
+ attr = g_attr_logical_length;
+ attr.val_ptr = &newsize;
+ osd_req_add_set_attr_list(or, &attr, 1);
+
+ /* 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 = exofs_sync_op(or, sbi->s_timeout, oi->i_cred);
+ osd_end_request(or);
+ 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;
+}
+
+/*
+ * Read an inode from the OSD, and return it as is. We also return the size
+ * attribute in the 'sanity' argument if we got compiled with debugging turned
+ * on.
+ */
+static int exofs_get_inode(struct super_block *sb, struct exofs_i_info *oi,
+ struct exofs_fcb *inode, uint64_t *sanity)
+{
+ struct exofs_sb_info *sbi = sb->s_fs_info;
+ struct osd_request *or;
+ struct osd_attr attr;
+ struct osd_obj_id obj = {sbi->s_pid,
+ oi->vfs_inode.i_ino + EXOFS_OBJ_OFF};
+ int ret;
+
+ exofs_make_credential(oi->i_cred, &obj);
+
+ or = osd_start_request(sbi->s_dev, GFP_KERNEL);
+ if (unlikely(!or)) {
+ EXOFS_ERR("exofs_get_inode: osd_start_request failed.\n");
+ return -ENOMEM;
+ }
+ osd_req_get_attributes(or, &obj);
+
+ /* we need the inode attribute */
+ osd_req_add_get_attr_list(or, &g_attr_inode_data, 1);
+
+#ifdef EXOFS_DEBUG_OBJ_ISIZE
+ /* we get the size attributes to do a sanity check */
+ osd_req_add_get_attr_list(or, &g_attr_logical_length, 1);
+#endif
+
+ ret = exofs_sync_op(or, sbi->s_timeout, oi->i_cred);
+ if (ret)
+ goto out;
+
+ attr = g_attr_inode_data;
+ ret = extract_attr_from_req(or, &attr);
+ if (ret) {
+ EXOFS_ERR("exofs_get_inode: extract_attr_from_req failed\n");
+ goto out;
+ }
+
+ WARN_ON(attr.len != EXOFS_INO_ATTR_SIZE);
+ memcpy(inode, attr.val_ptr, EXOFS_INO_ATTR_SIZE);
+
+#ifdef EXOFS_DEBUG_OBJ_ISIZE
+ attr = g_attr_logical_length;
+ ret = extract_attr_from_req(or, &attr);
+ if (ret) {
+ EXOFS_ERR("ERROR: extract attr from or failed\n");
+ goto out;
+ }
+ *sanity = get_unaligned_be64(attr.val_ptr);
+#endif
+
+out:
+ osd_end_request(or);
+ return ret;
+}
+
+/*
+ * 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;
+ uint64_t uninitialized_var(sanity);
+ 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);
+
+ /* read the inode from the osd */
+ ret = exofs_get_inode(sb, oi, &fcb, &sanity);
+ if (ret)
+ goto bad_inode;
+
+ init_waitqueue_head(&oi->i_wq);
+ 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);
+
+#ifdef EXOFS_DEBUG_OBJ_ISIZE
+ if ((inode->i_size != sanity) &&
+ (!exofs_inode_is_fast_symlink(inode))) {
+ EXOFS_ERR("WARNING: Size of object from inode and "
+ "attributes differ (%lld != %llu)\n",
+ inode->i_size, _LLU(sanity));
+ }
+#endif
+
+ 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 osd_request *or, 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_ok(or);
+ osd_end_request(or);
+ atomic_dec(&sbi->s_curr_pending);
+
+ if (unlikely(ret)) {
+ EXOFS_ERR("object=0x%llx creation faild in pid=0x%llx",
+ _LLU(sbi->s_pid), _LLU(inode->i_ino + EXOFS_OBJ_OFF));
+ make_bad_inode(inode);
+ } else
+ 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 osd_request *or;
+ struct osd_obj_id obj;
+ int ret;
+
+ sb = dir->i_sb;
+ inode = new_inode(sb);
+ if (!inode)
+ return ERR_PTR(-ENOMEM);
+
+ oi = exofs_i(inode);
+
+ init_waitqueue_head(&oi->i_wq);
+ 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);
+
+ obj.partition = sbi->s_pid;
+ obj.id = inode->i_ino + EXOFS_OBJ_OFF;
+ exofs_make_credential(oi->i_cred, &obj);
+
+ or = osd_start_request(sbi->s_dev, GFP_KERNEL);
+ if (unlikely(!or)) {
+ EXOFS_ERR("exofs_new_inode: osd_start_request failed\n");
+ return ERR_PTR(-ENOMEM);
+ }
+
+ osd_req_create_object(or, &obj);
+
+ /* increment the refcount so that the inode will still be around when we
+ * reach the callback
+ */
+ atomic_inc(&inode->i_count);
+
+ ret = exofs_async_op(or, create_done, inode, oi->i_cred);
+ if (ret) {
+ atomic_dec(&inode->i_count);
+ osd_end_request(or);
+ return ERR_PTR(-EIO);
+ }
+ 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 osd_request *or, void *p)
+{
+ struct updatei_args *args = p;
+
+ osd_end_request(or);
+
+ 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 osd_obj_id obj = {sbi->s_pid, inode->i_ino + EXOFS_OBJ_OFF};
+ struct osd_request *or;
+ struct osd_attr attr;
+ struct exofs_fcb *fcb;
+ struct updatei_args *args;
+ int ret;
+
+ args = kzalloc(sizeof(*args), GFP_KERNEL);
+ if (!args)
+ 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));
+
+ or = osd_start_request(sbi->s_dev, GFP_KERNEL);
+ if (unlikely(!or)) {
+ EXOFS_ERR("exofs_update_inode: osd_start_request failed.\n");
+ ret = -ENOMEM;
+ goto free_args;
+ }
+
+ osd_req_set_attributes(or, &obj);
+
+ attr = g_attr_inode_data;
+ attr.val_ptr = fcb;
+ osd_req_add_set_attr_list(or, &attr, 1);
+
+ 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) {
+ ret = exofs_sync_op(or, sbi->s_timeout, oi->i_cred);
+ osd_end_request(or);
+ goto free_args;
+ } else {
+ args->sbi = sbi;
+
+ ret = exofs_async_op(or, updatei_done, args, oi->i_cred);
+ if (ret) {
+ osd_end_request(or);
+ goto free_args;
+ }
+ atomic_inc(&sbi->s_curr_pending);
+ goto out; /* deallocation in updatei_done */
+ }
+
+free_args:
+ kfree(args);
+out:
+ EXOFS_DBGMSG("ret=>%d\n", ret);
+ return ret;
+}
+
+int exofs_write_inode(struct inode *inode, int wait)
+{
+ return exofs_update_inode(inode, wait);
+}
+
+/*
+ * Callback function from exofs_delete_inode() - don't have much cleaning up to
+ * do.
+ */
+static void delete_done(struct osd_request *or, void *p)
+{
+ struct exofs_sb_info *sbi;
+ osd_end_request(or);
+ sbi = p;
+ 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 osd_obj_id obj = {sbi->s_pid, inode->i_ino + EXOFS_OBJ_OFF};
+ struct osd_request *or;
+ 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);
+
+ or = osd_start_request(sbi->s_dev, GFP_KERNEL);
+ if (unlikely(!or)) {
+ EXOFS_ERR("exofs_delete_inode: osd_start_request failed\n");
+ return;
+ }
+
+ osd_req_remove_object(or, &obj);
+
+ /* 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));
+ }
+
+ ret = exofs_async_op(or, delete_done, sbi, oi->i_cred);
+ if (ret) {
+ EXOFS_ERR(
+ "ERROR: @exofs_delete_inode exofs_async_op failed\n");
+ osd_end_request(or);
+ return;
+ }
+ atomic_inc(&sbi->s_curr_pending);
+
+ return;
+
+no_delete:
+ clear_inode(inode);
+}