--- /dev/null
+/*
+ * Copyright (C) Sistina Software, Inc. 1997-2003 All rights reserved.
+ * Copyright (C) 2004-2006 Red Hat, Inc. All rights reserved.
+ *
+ * This copyrighted material is made available to anyone wishing to use,
+ * modify, copy, or redistribute it subject to the terms and conditions
+ * of the GNU General Public License version 2.
+ */
+
+#include <linux/sched.h>
+#include <linux/slab.h>
+#include <linux/spinlock.h>
+#include <linux/completion.h>
+#include <linux/buffer_head.h>
+#include <linux/pagemap.h>
+#include <linux/pagevec.h>
+#include <linux/mpage.h>
+#include <linux/fs.h>
+#include <linux/writeback.h>
+#include <linux/gfs2_ondisk.h>
+#include <linux/lm_interface.h>
+
+#include "gfs2.h"
+#include "incore.h"
+#include "bmap.h"
+#include "glock.h"
+#include "inode.h"
+#include "log.h"
+#include "meta_io.h"
+#include "ops_address.h"
+#include "quota.h"
+#include "trans.h"
+#include "rgrp.h"
+#include "ops_file.h"
+#include "util.h"
+#include "glops.h"
+
+
+static void gfs2_page_add_databufs(struct gfs2_inode *ip, struct page *page,
+ unsigned int from, unsigned int to)
+{
+ struct buffer_head *head = page_buffers(page);
+ unsigned int bsize = head->b_size;
+ struct buffer_head *bh;
+ unsigned int start, end;
+
+ for (bh = head, start = 0; bh != head || !start;
+ bh = bh->b_this_page, start = end) {
+ end = start + bsize;
+ if (end <= from || start >= to)
+ continue;
+ gfs2_trans_add_bh(ip->i_gl, bh, 0);
+ }
+}
+
+/**
+ * gfs2_get_block - Fills in a buffer head with details about a block
+ * @inode: The inode
+ * @lblock: The block number to look up
+ * @bh_result: The buffer head to return the result in
+ * @create: Non-zero if we may add block to the file
+ *
+ * Returns: errno
+ */
+
+int gfs2_get_block(struct inode *inode, sector_t lblock,
+ struct buffer_head *bh_result, int create)
+{
+ return gfs2_block_map(inode, lblock, create, bh_result);
+}
+
+/**
+ * gfs2_get_block_noalloc - Fills in a buffer head with details about a block
+ * @inode: The inode
+ * @lblock: The block number to look up
+ * @bh_result: The buffer head to return the result in
+ * @create: Non-zero if we may add block to the file
+ *
+ * Returns: errno
+ */
+
+static int gfs2_get_block_noalloc(struct inode *inode, sector_t lblock,
+ struct buffer_head *bh_result, int create)
+{
+ int error;
+
+ error = gfs2_block_map(inode, lblock, 0, bh_result);
+ if (error)
+ return error;
+ if (bh_result->b_blocknr == 0)
+ return -EIO;
+ return 0;
+}
+
+static int gfs2_get_block_direct(struct inode *inode, sector_t lblock,
+ struct buffer_head *bh_result, int create)
+{
+ return gfs2_block_map(inode, lblock, 0, bh_result);
+}
+
+/**
+ * gfs2_writepage - Write complete page
+ * @page: Page to write
+ *
+ * Returns: errno
+ *
+ * Some of this is copied from block_write_full_page() although we still
+ * call it to do most of the work.
+ */
+
+static int gfs2_writepage(struct page *page, struct writeback_control *wbc)
+{
+ struct inode *inode = page->mapping->host;
+ struct gfs2_inode *ip = GFS2_I(inode);
+ struct gfs2_sbd *sdp = GFS2_SB(inode);
+ loff_t i_size = i_size_read(inode);
+ pgoff_t end_index = i_size >> PAGE_CACHE_SHIFT;
+ unsigned offset;
+ int error;
+ int done_trans = 0;
+
+ if (gfs2_assert_withdraw(sdp, gfs2_glock_is_held_excl(ip->i_gl))) {
+ unlock_page(page);
+ return -EIO;
+ }
+ if (current->journal_info)
+ goto out_ignore;
+
+ /* Is the page fully outside i_size? (truncate in progress) */
+ offset = i_size & (PAGE_CACHE_SIZE-1);
+ if (page->index > end_index || (page->index == end_index && !offset)) {
+ page->mapping->a_ops->invalidatepage(page, 0);
+ unlock_page(page);
+ return 0; /* don't care */
+ }
+
+ if (sdp->sd_args.ar_data == GFS2_DATA_ORDERED || gfs2_is_jdata(ip)) {
+ error = gfs2_trans_begin(sdp, RES_DINODE + 1, 0);
+ if (error)
+ goto out_ignore;
+ if (!page_has_buffers(page)) {
+ create_empty_buffers(page, inode->i_sb->s_blocksize,
+ (1 << BH_Dirty)|(1 << BH_Uptodate));
+ }
+ gfs2_page_add_databufs(ip, page, 0, sdp->sd_vfs->s_blocksize-1);
+ done_trans = 1;
+ }
+ error = block_write_full_page(page, gfs2_get_block_noalloc, wbc);
+ if (done_trans)
+ gfs2_trans_end(sdp);
+ gfs2_meta_cache_flush(ip);
+ return error;
+
+out_ignore:
+ redirty_page_for_writepage(wbc, page);
+ unlock_page(page);
+ return 0;
+}
+
+/**
+ * gfs2_writepages - Write a bunch of dirty pages back to disk
+ * @mapping: The mapping to write
+ * @wbc: Write-back control
+ *
+ * For journaled files and/or ordered writes this just falls back to the
+ * kernel's default writepages path for now. We will probably want to change
+ * that eventually (i.e. when we look at allocate on flush).
+ *
+ * For the data=writeback case though we can already ignore buffer heads
+ * and write whole extents at once. This is a big reduction in the
+ * number of I/O requests we send and the bmap calls we make in this case.
+ */
+static int gfs2_writepages(struct address_space *mapping,
+ struct writeback_control *wbc)
+{
+ struct inode *inode = mapping->host;
+ struct gfs2_inode *ip = GFS2_I(inode);
+ struct gfs2_sbd *sdp = GFS2_SB(inode);
+
+ if (sdp->sd_args.ar_data == GFS2_DATA_WRITEBACK && !gfs2_is_jdata(ip))
+ return mpage_writepages(mapping, wbc, gfs2_get_block_noalloc);
+
+ return generic_writepages(mapping, wbc);
+}
+
+/**
+ * stuffed_readpage - Fill in a Linux page with stuffed file data
+ * @ip: the inode
+ * @page: the page
+ *
+ * Returns: errno
+ */
+
+static int stuffed_readpage(struct gfs2_inode *ip, struct page *page)
+{
+ struct buffer_head *dibh;
+ void *kaddr;
+ int error;
+
+ BUG_ON(page->index);
+
+ error = gfs2_meta_inode_buffer(ip, &dibh);
+ if (error)
+ return error;
+
+ kaddr = kmap_atomic(page, KM_USER0);
+ memcpy(kaddr, dibh->b_data + sizeof(struct gfs2_dinode),
+ ip->i_di.di_size);
+ memset(kaddr + ip->i_di.di_size, 0, PAGE_CACHE_SIZE - ip->i_di.di_size);
+ kunmap_atomic(kaddr, KM_USER0);
+
+ brelse(dibh);
+
+ SetPageUptodate(page);
+
+ return 0;
+}
+
+
+/**
+ * gfs2_readpage - readpage with locking
+ * @file: The file to read a page for. N.B. This may be NULL if we are
+ * reading an internal file.
+ * @page: The page to read
+ *
+ * Returns: errno
+ */
+
+static int gfs2_readpage(struct file *file, struct page *page)
+{
+ struct gfs2_inode *ip = GFS2_I(page->mapping->host);
+ struct gfs2_sbd *sdp = GFS2_SB(page->mapping->host);
+ struct gfs2_file *gf = NULL;
+ struct gfs2_holder gh;
+ int error;
+ int do_unlock = 0;
+
+ if (likely(file != &gfs2_internal_file_sentinel)) {
+ if (file) {
+ gf = file->private_data;
+ if (test_bit(GFF_EXLOCK, &gf->f_flags))
+ /* gfs2_sharewrite_nopage has grabbed the ip->i_gl already */
+ goto skip_lock;
+ }
+ gfs2_holder_init(ip->i_gl, LM_ST_SHARED, GL_ATIME|LM_FLAG_TRY_1CB, &gh);
+ do_unlock = 1;
+ error = gfs2_glock_nq_atime(&gh);
+ if (unlikely(error))
+ goto out_unlock;
+ }
+
+skip_lock:
+ if (gfs2_is_stuffed(ip)) {
+ error = stuffed_readpage(ip, page);
+ unlock_page(page);
+ } else
+ error = mpage_readpage(page, gfs2_get_block);
+
+ if (unlikely(test_bit(SDF_SHUTDOWN, &sdp->sd_flags)))
+ error = -EIO;
+
+ if (do_unlock) {
+ gfs2_glock_dq_m(1, &gh);
+ gfs2_holder_uninit(&gh);
+ }
+out:
+ return error;
+out_unlock:
+ unlock_page(page);
+ if (error == GLR_TRYFAILED) {
+ error = AOP_TRUNCATED_PAGE;
+ yield();
+ }
+ if (do_unlock)
+ gfs2_holder_uninit(&gh);
+ goto out;
+}
+
+/**
+ * gfs2_readpages - Read a bunch of pages at once
+ *
+ * Some notes:
+ * 1. This is only for readahead, so we can simply ignore any things
+ * which are slightly inconvenient (such as locking conflicts between
+ * the page lock and the glock) and return having done no I/O. Its
+ * obviously not something we'd want to do on too regular a basis.
+ * Any I/O we ignore at this time will be done via readpage later.
+ * 2. We don't handle stuffed files here we let readpage do the honours.
+ * 3. mpage_readpages() does most of the heavy lifting in the common case.
+ * 4. gfs2_get_block() is relied upon to set BH_Boundary in the right places.
+ * 5. We use LM_FLAG_TRY_1CB here, effectively we then have lock-ahead as
+ * well as read-ahead.
+ */
+static int gfs2_readpages(struct file *file, struct address_space *mapping,
+ struct list_head *pages, unsigned nr_pages)
+{
+ struct inode *inode = mapping->host;
+ struct gfs2_inode *ip = GFS2_I(inode);
+ struct gfs2_sbd *sdp = GFS2_SB(inode);
+ struct gfs2_holder gh;
+ int ret = 0;
+ int do_unlock = 0;
+
+ if (likely(file != &gfs2_internal_file_sentinel)) {
+ if (file) {
+ struct gfs2_file *gf = file->private_data;
+ if (test_bit(GFF_EXLOCK, &gf->f_flags))
+ goto skip_lock;
+ }
+ gfs2_holder_init(ip->i_gl, LM_ST_SHARED,
+ LM_FLAG_TRY_1CB|GL_ATIME, &gh);
+ do_unlock = 1;
+ ret = gfs2_glock_nq_atime(&gh);
+ if (ret == GLR_TRYFAILED)
+ goto out_noerror;
+ if (unlikely(ret))
+ goto out_unlock;
+ }
+skip_lock:
+ if (!gfs2_is_stuffed(ip))
+ ret = mpage_readpages(mapping, pages, nr_pages, gfs2_get_block);
+
+ if (do_unlock) {
+ gfs2_glock_dq_m(1, &gh);
+ gfs2_holder_uninit(&gh);
+ }
+out:
+ if (unlikely(test_bit(SDF_SHUTDOWN, &sdp->sd_flags)))
+ ret = -EIO;
+ return ret;
+out_noerror:
+ ret = 0;
+out_unlock:
+ if (do_unlock)
+ gfs2_holder_uninit(&gh);
+ goto out;
+}
+
+/**
+ * gfs2_prepare_write - Prepare to write a page to a file
+ * @file: The file to write to
+ * @page: The page which is to be prepared for writing
+ * @from: From (byte range within page)
+ * @to: To (byte range within page)
+ *
+ * Returns: errno
+ */
+
+static int gfs2_prepare_write(struct file *file, struct page *page,
+ unsigned from, unsigned to)
+{
+ struct gfs2_inode *ip = GFS2_I(page->mapping->host);
+ struct gfs2_sbd *sdp = GFS2_SB(page->mapping->host);
+ unsigned int data_blocks, ind_blocks, rblocks;
+ int alloc_required;
+ int error = 0;
+ loff_t pos = ((loff_t)page->index << PAGE_CACHE_SHIFT) + from;
+ loff_t end = ((loff_t)page->index << PAGE_CACHE_SHIFT) + to;
+ struct gfs2_alloc *al;
+ unsigned int write_len = to - from;
+
+
+ gfs2_holder_init(ip->i_gl, LM_ST_EXCLUSIVE, GL_ATIME|LM_FLAG_TRY_1CB, &ip->i_gh);
+ error = gfs2_glock_nq_atime(&ip->i_gh);
+ if (unlikely(error)) {
+ if (error == GLR_TRYFAILED) {
+ unlock_page(page);
+ error = AOP_TRUNCATED_PAGE;
+ yield();
+ }
+ goto out_uninit;
+ }
+
+ gfs2_write_calc_reserv(ip, write_len, &data_blocks, &ind_blocks);
+
+ error = gfs2_write_alloc_required(ip, pos, write_len, &alloc_required);
+ if (error)
+ goto out_unlock;
+
+
+ ip->i_alloc.al_requested = 0;
+ if (alloc_required) {
+ al = gfs2_alloc_get(ip);
+
+ error = gfs2_quota_lock(ip, NO_QUOTA_CHANGE, NO_QUOTA_CHANGE);
+ if (error)
+ goto out_alloc_put;
+
+ error = gfs2_quota_check(ip, ip->i_inode.i_uid, ip->i_inode.i_gid);
+ if (error)
+ goto out_qunlock;
+
+ al->al_requested = data_blocks + ind_blocks;
+ error = gfs2_inplace_reserve(ip);
+ if (error)
+ goto out_qunlock;
+ }
+
+ rblocks = RES_DINODE + ind_blocks;
+ if (gfs2_is_jdata(ip))
+ rblocks += data_blocks ? data_blocks : 1;
+ if (ind_blocks || data_blocks)
+ rblocks += RES_STATFS + RES_QUOTA;
+
+ error = gfs2_trans_begin(sdp, rblocks, 0);
+ if (error)
+ goto out;
+
+ if (gfs2_is_stuffed(ip)) {
+ if (end > sdp->sd_sb.sb_bsize - sizeof(struct gfs2_dinode)) {
+ error = gfs2_unstuff_dinode(ip, page);
+ if (error == 0)
+ goto prepare_write;
+ } else if (!PageUptodate(page))
+ error = stuffed_readpage(ip, page);
+ goto out;
+ }
+
+prepare_write:
+ error = block_prepare_write(page, from, to, gfs2_get_block);
+
+out:
+ if (error) {
+ gfs2_trans_end(sdp);
+ if (alloc_required) {
+ gfs2_inplace_release(ip);
+out_qunlock:
+ gfs2_quota_unlock(ip);
+out_alloc_put:
+ gfs2_alloc_put(ip);
+ }
+out_unlock:
+ gfs2_glock_dq_m(1, &ip->i_gh);
+out_uninit:
+ gfs2_holder_uninit(&ip->i_gh);
+ }
+
+ return error;
+}
+
+/**
+ * gfs2_commit_write - Commit write to a file
+ * @file: The file to write to
+ * @page: The page containing the data
+ * @from: From (byte range within page)
+ * @to: To (byte range within page)
+ *
+ * Returns: errno
+ */
+
+static int gfs2_commit_write(struct file *file, struct page *page,
+ unsigned from, unsigned to)
+{
+ struct inode *inode = page->mapping->host;
+ struct gfs2_inode *ip = GFS2_I(inode);
+ struct gfs2_sbd *sdp = GFS2_SB(inode);
+ int error = -EOPNOTSUPP;
+ struct buffer_head *dibh;
+ struct gfs2_alloc *al = &ip->i_alloc;
+ struct gfs2_dinode *di;
+
+ if (gfs2_assert_withdraw(sdp, gfs2_glock_is_locked_by_me(ip->i_gl)))
+ goto fail_nounlock;
+
+ error = gfs2_meta_inode_buffer(ip, &dibh);
+ if (error)
+ goto fail_endtrans;
+
+ gfs2_trans_add_bh(ip->i_gl, dibh, 1);
+ di = (struct gfs2_dinode *)dibh->b_data;
+
+ if (gfs2_is_stuffed(ip)) {
+ u64 file_size;
+ void *kaddr;
+
+ file_size = ((u64)page->index << PAGE_CACHE_SHIFT) + to;
+
+ kaddr = kmap_atomic(page, KM_USER0);
+ memcpy(dibh->b_data + sizeof(struct gfs2_dinode) + from,
+ kaddr + from, to - from);
+ kunmap_atomic(kaddr, KM_USER0);
+
+ SetPageUptodate(page);
+
+ if (inode->i_size < file_size) {
+ i_size_write(inode, file_size);
+ mark_inode_dirty(inode);
+ }
+ } else {
+ if (sdp->sd_args.ar_data == GFS2_DATA_ORDERED ||
+ gfs2_is_jdata(ip))
+ gfs2_page_add_databufs(ip, page, from, to);
+ error = generic_commit_write(file, page, from, to);
+ if (error)
+ goto fail;
+ }
+
+ if (ip->i_di.di_size < inode->i_size) {
+ ip->i_di.di_size = inode->i_size;
+ di->di_size = cpu_to_be64(inode->i_size);
+ }
+
+ brelse(dibh);
+ gfs2_trans_end(sdp);
+ if (al->al_requested) {
+ gfs2_inplace_release(ip);
+ gfs2_quota_unlock(ip);
+ gfs2_alloc_put(ip);
+ }
+ unlock_page(page);
+ gfs2_glock_dq_m(1, &ip->i_gh);
+ lock_page(page);
+ gfs2_holder_uninit(&ip->i_gh);
+ return 0;
+
+fail:
+ brelse(dibh);
+fail_endtrans:
+ gfs2_trans_end(sdp);
+ if (al->al_requested) {
+ gfs2_inplace_release(ip);
+ gfs2_quota_unlock(ip);
+ gfs2_alloc_put(ip);
+ }
+ unlock_page(page);
+ gfs2_glock_dq_m(1, &ip->i_gh);
+ lock_page(page);
+ gfs2_holder_uninit(&ip->i_gh);
+fail_nounlock:
+ ClearPageUptodate(page);
+ return error;
+}
+
+/**
+ * gfs2_bmap - Block map function
+ * @mapping: Address space info
+ * @lblock: The block to map
+ *
+ * Returns: The disk address for the block or 0 on hole or error
+ */
+
+static sector_t gfs2_bmap(struct address_space *mapping, sector_t lblock)
+{
+ struct gfs2_inode *ip = GFS2_I(mapping->host);
+ struct gfs2_holder i_gh;
+ sector_t dblock = 0;
+ int error;
+
+ error = gfs2_glock_nq_init(ip->i_gl, LM_ST_SHARED, LM_FLAG_ANY, &i_gh);
+ if (error)
+ return 0;
+
+ if (!gfs2_is_stuffed(ip))
+ dblock = generic_block_bmap(mapping, lblock, gfs2_get_block);
+
+ gfs2_glock_dq_uninit(&i_gh);
+
+ return dblock;
+}
+
+static void discard_buffer(struct gfs2_sbd *sdp, struct buffer_head *bh)
+{
+ struct gfs2_bufdata *bd;
+
+ gfs2_log_lock(sdp);
+ bd = bh->b_private;
+ if (bd) {
+ bd->bd_bh = NULL;
+ bh->b_private = NULL;
+ }
+ gfs2_log_unlock(sdp);
+
+ lock_buffer(bh);
+ clear_buffer_dirty(bh);
+ bh->b_bdev = NULL;
+ clear_buffer_mapped(bh);
+ clear_buffer_req(bh);
+ clear_buffer_new(bh);
+ clear_buffer_delay(bh);
+ unlock_buffer(bh);
+}
+
+static void gfs2_invalidatepage(struct page *page, unsigned long offset)
+{
+ struct gfs2_sbd *sdp = GFS2_SB(page->mapping->host);
+ struct buffer_head *head, *bh, *next;
+ unsigned int curr_off = 0;
+
+ BUG_ON(!PageLocked(page));
+ if (!page_has_buffers(page))
+ return;
+
+ bh = head = page_buffers(page);
+ do {
+ unsigned int next_off = curr_off + bh->b_size;
+ next = bh->b_this_page;
+
+ if (offset <= curr_off)
+ discard_buffer(sdp, bh);
+
+ curr_off = next_off;
+ bh = next;
+ } while (bh != head);
+
+ if (!offset)
+ try_to_release_page(page, 0);
+
+ return;
+}
+
+/**
+ * gfs2_ok_for_dio - check that dio is valid on this file
+ * @ip: The inode
+ * @rw: READ or WRITE
+ * @offset: The offset at which we are reading or writing
+ *
+ * Returns: 0 (to ignore the i/o request and thus fall back to buffered i/o)
+ * 1 (to accept the i/o request)
+ */
+static int gfs2_ok_for_dio(struct gfs2_inode *ip, int rw, loff_t offset)
+{
+ /*
+ * Should we return an error here? I can't see that O_DIRECT for
+ * a journaled file makes any sense. For now we'll silently fall
+ * back to buffered I/O, likewise we do the same for stuffed
+ * files since they are (a) small and (b) unaligned.
+ */
+ if (gfs2_is_jdata(ip))
+ return 0;
+
+ if (gfs2_is_stuffed(ip))
+ return 0;
+
+ if (offset > i_size_read(&ip->i_inode))
+ return 0;
+ return 1;
+}
+
+
+
+static ssize_t gfs2_direct_IO(int rw, struct kiocb *iocb,
+ const struct iovec *iov, loff_t offset,
+ unsigned long nr_segs)
+{
+ struct file *file = iocb->ki_filp;
+ struct inode *inode = file->f_mapping->host;
+ struct gfs2_inode *ip = GFS2_I(inode);
+ struct gfs2_holder gh;
+ int rv;
+
+ /*
+ * Deferred lock, even if its a write, since we do no allocation
+ * on this path. All we need change is atime, and this lock mode
+ * ensures that other nodes have flushed their buffered read caches
+ * (i.e. their page cache entries for this inode). We do not,
+ * unfortunately have the option of only flushing a range like
+ * the VFS does.
+ */
+ gfs2_holder_init(ip->i_gl, LM_ST_DEFERRED, GL_ATIME, &gh);
+ rv = gfs2_glock_nq_atime(&gh);
+ if (rv)
+ return rv;
+ rv = gfs2_ok_for_dio(ip, rw, offset);
+ if (rv != 1)
+ goto out; /* dio not valid, fall back to buffered i/o */
+
+ rv = blockdev_direct_IO_no_locking(rw, iocb, inode, inode->i_sb->s_bdev,
+ iov, offset, nr_segs,
+ gfs2_get_block_direct, NULL);
+out:
+ gfs2_glock_dq_m(1, &gh);
+ gfs2_holder_uninit(&gh);
+ return rv;
+}
+
+/**
+ * stuck_releasepage - We're stuck in gfs2_releasepage(). Print stuff out.
+ * @bh: the buffer we're stuck on
+ *
+ */
+
+static void stuck_releasepage(struct buffer_head *bh)
+{
+ struct inode *inode = bh->b_page->mapping->host;
+ struct gfs2_sbd *sdp = inode->i_sb->s_fs_info;
+ struct gfs2_bufdata *bd = bh->b_private;
+ struct gfs2_glock *gl;
+static unsigned limit = 0;
+
+ if (limit > 3)
+ return;
+ limit++;
+
+ fs_warn(sdp, "stuck in gfs2_releasepage() %p\n", inode);
+ fs_warn(sdp, "blkno = %llu, bh->b_count = %d\n",
+ (unsigned long long)bh->b_blocknr, atomic_read(&bh->b_count));
+ fs_warn(sdp, "pinned = %u\n", buffer_pinned(bh));
+ fs_warn(sdp, "bh->b_private = %s\n", (bd) ? "!NULL" : "NULL");
+
+ if (!bd)
+ return;
+
+ gl = bd->bd_gl;
+
+ fs_warn(sdp, "gl = (%u, %llu)\n",
+ gl->gl_name.ln_type, (unsigned long long)gl->gl_name.ln_number);
+
+ fs_warn(sdp, "bd_list_tr = %s, bd_le.le_list = %s\n",
+ (list_empty(&bd->bd_list_tr)) ? "no" : "yes",
+ (list_empty(&bd->bd_le.le_list)) ? "no" : "yes");
+
+ if (gl->gl_ops == &gfs2_inode_glops) {
+ struct gfs2_inode *ip = gl->gl_object;
+ unsigned int x;
+
+ if (!ip)
+ return;
+
+ fs_warn(sdp, "ip = %llu %llu\n",
+ (unsigned long long)ip->i_num.no_formal_ino,
+ (unsigned long long)ip->i_num.no_addr);
+
+ for (x = 0; x < GFS2_MAX_META_HEIGHT; x++)
+ fs_warn(sdp, "ip->i_cache[%u] = %s\n",
+ x, (ip->i_cache[x]) ? "!NULL" : "NULL");
+ }
+}
+
+/**
+ * gfs2_releasepage - free the metadata associated with a page
+ * @page: the page that's being released
+ * @gfp_mask: passed from Linux VFS, ignored by us
+ *
+ * Call try_to_free_buffers() if the buffers in this page can be
+ * released.
+ *
+ * Returns: 0
+ */
+
+int gfs2_releasepage(struct page *page, gfp_t gfp_mask)
+{
+ struct inode *aspace = page->mapping->host;
+ struct gfs2_sbd *sdp = aspace->i_sb->s_fs_info;
+ struct buffer_head *bh, *head;
+ struct gfs2_bufdata *bd;
+ unsigned long t = jiffies + gfs2_tune_get(sdp, gt_stall_secs) * HZ;
+
+ if (!page_has_buffers(page))
+ goto out;
+
+ head = bh = page_buffers(page);
+ do {
+ while (atomic_read(&bh->b_count)) {
+ if (!atomic_read(&aspace->i_writecount))
+ return 0;
+
+ if (!(gfp_mask & __GFP_WAIT))
+ return 0;
+
+ if (time_after_eq(jiffies, t)) {
+ stuck_releasepage(bh);
+ /* should we withdraw here? */
+ return 0;
+ }
+
+ yield();
+ }
+
+ gfs2_assert_warn(sdp, !buffer_pinned(bh));
+ gfs2_assert_warn(sdp, !buffer_dirty(bh));
+
+ gfs2_log_lock(sdp);
+ bd = bh->b_private;
+ if (bd) {
+ gfs2_assert_warn(sdp, bd->bd_bh == bh);
+ gfs2_assert_warn(sdp, list_empty(&bd->bd_list_tr));
+ gfs2_assert_warn(sdp, !bd->bd_ail);
+ bd->bd_bh = NULL;
+ if (!list_empty(&bd->bd_le.le_list))
+ bd = NULL;
+ bh->b_private = NULL;
+ }
+ gfs2_log_unlock(sdp);
+ if (bd)
+ kmem_cache_free(gfs2_bufdata_cachep, bd);
+
+ bh = bh->b_this_page;
+ } while (bh != head);
+
+out:
+ return try_to_free_buffers(page);
+}
+
+const struct address_space_operations gfs2_file_aops = {
+ .writepage = gfs2_writepage,
+ .writepages = gfs2_writepages,
+ .readpage = gfs2_readpage,
+ .readpages = gfs2_readpages,
+ .sync_page = block_sync_page,
+ .prepare_write = gfs2_prepare_write,
+ .commit_write = gfs2_commit_write,
+ .bmap = gfs2_bmap,
+ .invalidatepage = gfs2_invalidatepage,
+ .releasepage = gfs2_releasepage,
+ .direct_IO = gfs2_direct_IO,
+};
+
git://git.onelab.eu / linux-2.6.git / blobdiff