1 files changed, 615 insertions, 0 deletions

diff --git a/fs/gfs2/glops.c b/fs/gfs2/glops.c
new file mode 100644
index 0000000..41a6b68
--- /dev/null
+++ b/fs/gfs2/glops.c
@@ -0,0 +1,615 @@
+/*
+ * 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/gfs2_ondisk.h>
+#include <linux/lm_interface.h>
+
+#include "gfs2.h"
+#include "incore.h"
+#include "bmap.h"
+#include "glock.h"
+#include "glops.h"
+#include "inode.h"
+#include "log.h"
+#include "meta_io.h"
+#include "recovery.h"
+#include "rgrp.h"
+#include "util.h"
+#include "trans.h"
+
+/**
+ * ail_empty_gl - remove all buffers for a given lock from the AIL
+ * @gl: the glock
+ *
+ * None of the buffers should be dirty, locked, or pinned.
+ */
+
+static void gfs2_ail_empty_gl(struct gfs2_glock *gl)
+{
+	struct gfs2_sbd *sdp = gl->gl_sbd;
+	unsigned int blocks;
+	struct list_head *head = &gl->gl_ail_list;
+	struct gfs2_bufdata *bd;
+	struct buffer_head *bh;
+	u64 blkno;
+	int error;
+
+	blocks = atomic_read(&gl->gl_ail_count);
+	if (!blocks)
+		return;
+
+	error = gfs2_trans_begin(sdp, 0, blocks);
+	if (gfs2_assert_withdraw(sdp, !error))
+		return;
+
+	gfs2_log_lock(sdp);
+	while (!list_empty(head)) {
+		bd = list_entry(head->next, struct gfs2_bufdata,
+				bd_ail_gl_list);
+		bh = bd->bd_bh;
+		blkno = bh->b_blocknr;
+		gfs2_assert_withdraw(sdp, !buffer_busy(bh));
+
+		bd->bd_ail = NULL;
+		list_del(&bd->bd_ail_st_list);
+		list_del(&bd->bd_ail_gl_list);
+		atomic_dec(&gl->gl_ail_count);
+		brelse(bh);
+		gfs2_log_unlock(sdp);
+
+		gfs2_trans_add_revoke(sdp, blkno);
+
+		gfs2_log_lock(sdp);
+	}
+	gfs2_assert_withdraw(sdp, !atomic_read(&gl->gl_ail_count));
+	gfs2_log_unlock(sdp);
+
+	gfs2_trans_end(sdp);
+	gfs2_log_flush(sdp, NULL);
+}
+
+/**
+ * gfs2_pte_inval - Sync and invalidate all PTEs associated with a glock
+ * @gl: the glock
+ *
+ */
+
+static void gfs2_pte_inval(struct gfs2_glock *gl)
+{
+	struct gfs2_inode *ip;
+	struct inode *inode;
+
+	ip = gl->gl_object;
+	inode = &ip->i_inode;
+	if (!ip || !S_ISREG(ip->i_di.di_mode))
+		return;
+
+	if (!test_bit(GIF_PAGED, &ip->i_flags))
+		return;
+
+	unmap_shared_mapping_range(inode->i_mapping, 0, 0);
+
+	if (test_bit(GIF_SW_PAGED, &ip->i_flags))
+		set_bit(GLF_DIRTY, &gl->gl_flags);
+
+	clear_bit(GIF_SW_PAGED, &ip->i_flags);
+}
+
+/**
+ * gfs2_page_inval - Invalidate all pages associated with a glock
+ * @gl: the glock
+ *
+ */
+
+static void gfs2_page_inval(struct gfs2_glock *gl)
+{
+	struct gfs2_inode *ip;
+	struct inode *inode;
+
+	ip = gl->gl_object;
+	inode = &ip->i_inode;
+	if (!ip || !S_ISREG(ip->i_di.di_mode))
+		return;
+
+	truncate_inode_pages(inode->i_mapping, 0);
+	gfs2_assert_withdraw(GFS2_SB(&ip->i_inode), !inode->i_mapping->nrpages);
+	clear_bit(GIF_PAGED, &ip->i_flags);
+}
+
+/**
+ * gfs2_page_wait - Wait for writeback of data
+ * @gl: the glock
+ *
+ * Syncs data (not metadata) for a regular file.
+ * No-op for all other types.
+ */
+
+static void gfs2_page_wait(struct gfs2_glock *gl)
+{
+	struct gfs2_inode *ip = gl->gl_object;
+	struct inode *inode = &ip->i_inode;
+	struct address_space *mapping = inode->i_mapping;
+	int error;
+
+	if (!S_ISREG(ip->i_di.di_mode))
+		return;
+
+	error = filemap_fdatawait(mapping);
+
+	/* Put back any errors cleared by filemap_fdatawait()
+	   so they can be caught by someone who can pass them
+	   up to user space. */
+
+	if (error == -ENOSPC)
+		set_bit(AS_ENOSPC, &mapping->flags);
+	else if (error)
+		set_bit(AS_EIO, &mapping->flags);
+
+}
+
+static void gfs2_page_writeback(struct gfs2_glock *gl)
+{
+	struct gfs2_inode *ip = gl->gl_object;
+	struct inode *inode = &ip->i_inode;
+	struct address_space *mapping = inode->i_mapping;
+
+	if (!S_ISREG(ip->i_di.di_mode))
+		return;
+
+	filemap_fdatawrite(mapping);
+}
+
+/**
+ * meta_go_sync - sync out the metadata for this glock
+ * @gl: the glock
+ * @flags: DIO_*
+ *
+ * Called when demoting or unlocking an EX glock.  We must flush
+ * to disk all dirty buffers/pages relating to this glock, and must not
+ * not return to caller to demote/unlock the glock until I/O is complete.
+ */
+
+static void meta_go_sync(struct gfs2_glock *gl, int flags)
+{
+	if (!(flags & DIO_METADATA))
+		return;
+
+	if (test_and_clear_bit(GLF_DIRTY, &gl->gl_flags)) {
+		gfs2_log_flush(gl->gl_sbd, gl);
+		gfs2_meta_sync(gl);
+		if (flags & DIO_RELEASE)
+			gfs2_ail_empty_gl(gl);
+	}
+
+}
+
+/**
+ * meta_go_inval - invalidate the metadata for this glock
+ * @gl: the glock
+ * @flags:
+ *
+ */
+
+static void meta_go_inval(struct gfs2_glock *gl, int flags)
+{
+	if (!(flags & DIO_METADATA))
+		return;
+
+	gfs2_meta_inval(gl);
+	gl->gl_vn++;
+}
+
+/**
+ * inode_go_xmote_th - promote/demote a glock
+ * @gl: the glock
+ * @state: the requested state
+ * @flags:
+ *
+ */
+
+static void inode_go_xmote_th(struct gfs2_glock *gl, unsigned int state,
+			      int flags)
+{
+	if (gl->gl_state != LM_ST_UNLOCKED)
+		gfs2_pte_inval(gl);
+	gfs2_glock_xmote_th(gl, state, flags);
+}
+
+/**
+ * inode_go_xmote_bh - After promoting/demoting a glock
+ * @gl: the glock
+ *
+ */
+
+static void inode_go_xmote_bh(struct gfs2_glock *gl)
+{
+	struct gfs2_holder *gh = gl->gl_req_gh;
+	struct buffer_head *bh;
+	int error;
+
+	if (gl->gl_state != LM_ST_UNLOCKED &&
+	    (!gh || !(gh->gh_flags & GL_SKIP))) {
+		error = gfs2_meta_read(gl, gl->gl_name.ln_number, 0, &bh);
+		if (!error)
+			brelse(bh);
+	}
+}
+
+/**
+ * inode_go_drop_th - unlock a glock
+ * @gl: the glock
+ *
+ * Invoked from rq_demote().
+ * Another node needs the lock in EXCLUSIVE mode, or lock (unused for too long)
+ * is being purged from our node's glock cache; we're dropping lock.
+ */
+
+static void inode_go_drop_th(struct gfs2_glock *gl)
+{
+	gfs2_pte_inval(gl);
+	gfs2_glock_drop_th(gl);
+}
+
+/**
+ * inode_go_sync - Sync the dirty data and/or metadata for an inode glock
+ * @gl: the glock protecting the inode
+ * @flags:
+ *
+ */
+
+static void inode_go_sync(struct gfs2_glock *gl, int flags)
+{
+	int meta = (flags & DIO_METADATA);
+	int data = (flags & DIO_DATA);
+
+	if (test_bit(GLF_DIRTY, &gl->gl_flags)) {
+		if (meta && data) {
+			gfs2_page_writeback(gl);
+			gfs2_log_flush(gl->gl_sbd, gl);
+			gfs2_meta_sync(gl);
+			gfs2_page_wait(gl);
+			clear_bit(GLF_DIRTY, &gl->gl_flags);
+		} else if (meta) {
+			gfs2_log_flush(gl->gl_sbd, gl);
+			gfs2_meta_sync(gl);
+		} else if (data) {
+			gfs2_page_writeback(gl);
+			gfs2_page_wait(gl);
+		}
+		if (flags & DIO_RELEASE)
+			gfs2_ail_empty_gl(gl);
+	}
+}
+
+/**
+ * inode_go_inval - prepare a inode glock to be released
+ * @gl: the glock
+ * @flags:
+ *
+ */
+
+static void inode_go_inval(struct gfs2_glock *gl, int flags)
+{
+	int meta = (flags & DIO_METADATA);
+	int data = (flags & DIO_DATA);
+
+	if (meta) {
+		gfs2_meta_inval(gl);
+		gl->gl_vn++;
+	}
+	if (data)
+		gfs2_page_inval(gl);
+}
+
+/**
+ * inode_go_demote_ok - Check to see if it's ok to unlock an inode glock
+ * @gl: the glock
+ *
+ * Returns: 1 if it's ok
+ */
+
+static int inode_go_demote_ok(struct gfs2_glock *gl)
+{
+	struct gfs2_sbd *sdp = gl->gl_sbd;
+	int demote = 0;
+
+	if (!gl->gl_object && !gl->gl_aspace->i_mapping->nrpages)
+		demote = 1;
+	else if (!sdp->sd_args.ar_localcaching &&
+		 time_after_eq(jiffies, gl->gl_stamp +
+			       gfs2_tune_get(sdp, gt_demote_secs) * HZ))
+		demote = 1;
+
+	return demote;
+}
+
+/**
+ * inode_go_lock - operation done after an inode lock is locked by a process
+ * @gl: the glock
+ * @flags:
+ *
+ * Returns: errno
+ */
+
+static int inode_go_lock(struct gfs2_holder *gh)
+{
+	struct gfs2_glock *gl = gh->gh_gl;
+	struct gfs2_inode *ip = gl->gl_object;
+	int error = 0;
+
+	if (!ip)
+		return 0;
+
+	if (ip->i_vn != gl->gl_vn) {
+		error = gfs2_inode_refresh(ip);
+		if (error)
+			return error;
+		gfs2_inode_attr_in(ip);
+	}
+
+	if ((ip->i_di.di_flags & GFS2_DIF_TRUNC_IN_PROG) &&
+	    (gl->gl_state == LM_ST_EXCLUSIVE) &&
+	    (gh->gh_flags & GL_LOCAL_EXCL))
+		error = gfs2_truncatei_resume(ip);
+
+	return error;
+}
+
+/**
+ * inode_go_unlock - operation done before an inode lock is unlocked by a
+ *		     process
+ * @gl: the glock
+ * @flags:
+ *
+ */
+
+static void inode_go_unlock(struct gfs2_holder *gh)
+{
+	struct gfs2_glock *gl = gh->gh_gl;
+	struct gfs2_inode *ip = gl->gl_object;
+
+	if (ip == NULL)
+		return;
+	if (test_bit(GLF_DIRTY, &gl->gl_flags))
+		gfs2_inode_attr_in(ip);
+	gfs2_meta_cache_flush(ip);
+}
+
+/**
+ * inode_greedy -
+ * @gl: the glock
+ *
+ */
+
+static void inode_greedy(struct gfs2_glock *gl)
+{
+	struct gfs2_sbd *sdp = gl->gl_sbd;
+	struct gfs2_inode *ip = gl->gl_object;
+	unsigned int quantum = gfs2_tune_get(sdp, gt_greedy_quantum);
+	unsigned int max = gfs2_tune_get(sdp, gt_greedy_max);
+	unsigned int new_time;
+
+	spin_lock(&ip->i_spin);
+
+	if (time_after(ip->i_last_pfault + quantum, jiffies)) {
+		new_time = ip->i_greedy + quantum;
+		if (new_time > max)
+			new_time = max;
+	} else {
+		new_time = ip->i_greedy - quantum;
+		if (!new_time || new_time > max)
+			new_time = 1;
+	}
+
+	ip->i_greedy = new_time;
+
+	spin_unlock(&ip->i_spin);
+
+	iput(&ip->i_inode);
+}
+
+/**
+ * rgrp_go_demote_ok - Check to see if it's ok to unlock a RG's glock
+ * @gl: the glock
+ *
+ * Returns: 1 if it's ok
+ */
+
+static int rgrp_go_demote_ok(struct gfs2_glock *gl)
+{
+	return !gl->gl_aspace->i_mapping->nrpages;
+}
+
+/**
+ * rgrp_go_lock - operation done after an rgrp lock is locked by
+ *    a first holder on this node.
+ * @gl: the glock
+ * @flags:
+ *
+ * Returns: errno
+ */
+
+static int rgrp_go_lock(struct gfs2_holder *gh)
+{
+	return gfs2_rgrp_bh_get(gh->gh_gl->gl_object);
+}
+
+/**
+ * rgrp_go_unlock - operation done before an rgrp lock is unlocked by
+ *    a last holder on this node.
+ * @gl: the glock
+ * @flags:
+ *
+ */
+
+static void rgrp_go_unlock(struct gfs2_holder *gh)
+{
+	gfs2_rgrp_bh_put(gh->gh_gl->gl_object);
+}
+
+/**
+ * trans_go_xmote_th - promote/demote the transaction glock
+ * @gl: the glock
+ * @state: the requested state
+ * @flags:
+ *
+ */
+
+static void trans_go_xmote_th(struct gfs2_glock *gl, unsigned int state,
+			      int flags)
+{
+	struct gfs2_sbd *sdp = gl->gl_sbd;
+
+	if (gl->gl_state != LM_ST_UNLOCKED &&
+	    test_bit(SDF_JOURNAL_LIVE, &sdp->sd_flags)) {
+		gfs2_meta_syncfs(sdp);
+		gfs2_log_shutdown(sdp);
+	}
+
+	gfs2_glock_xmote_th(gl, state, flags);
+}
+
+/**
+ * trans_go_xmote_bh - After promoting/demoting the transaction glock
+ * @gl: the glock
+ *
+ */
+
+static void trans_go_xmote_bh(struct gfs2_glock *gl)
+{
+	struct gfs2_sbd *sdp = gl->gl_sbd;
+	struct gfs2_inode *ip = GFS2_I(sdp->sd_jdesc->jd_inode);
+	struct gfs2_glock *j_gl = ip->i_gl;
+	struct gfs2_log_header head;
+	int error;
+
+	if (gl->gl_state != LM_ST_UNLOCKED &&
+	    test_bit(SDF_JOURNAL_LIVE, &sdp->sd_flags)) {
+		gfs2_meta_cache_flush(GFS2_I(sdp->sd_jdesc->jd_inode));
+		j_gl->gl_ops->go_inval(j_gl, DIO_METADATA | DIO_DATA);
+
+		error = gfs2_find_jhead(sdp->sd_jdesc, &head);
+		if (error)
+			gfs2_consist(sdp);
+		if (!(head.lh_flags & GFS2_LOG_HEAD_UNMOUNT))
+			gfs2_consist(sdp);
+
+		/*  Initialize some head of the log stuff  */
+		if (!test_bit(SDF_SHUTDOWN, &sdp->sd_flags)) {
+			sdp->sd_log_sequence = head.lh_sequence + 1;
+			gfs2_log_pointers_init(sdp, head.lh_blkno);
+		}
+	}
+}
+
+/**
+ * trans_go_drop_th - unlock the transaction glock
+ * @gl: the glock
+ *
+ * We want to sync the device even with localcaching.  Remember
+ * that localcaching journal replay only marks buffers dirty.
+ */
+
+static void trans_go_drop_th(struct gfs2_glock *gl)
+{
+	struct gfs2_sbd *sdp = gl->gl_sbd;
+
+	if (test_bit(SDF_JOURNAL_LIVE, &sdp->sd_flags)) {
+		gfs2_meta_syncfs(sdp);
+		gfs2_log_shutdown(sdp);
+	}
+
+	gfs2_glock_drop_th(gl);
+}
+
+/**
+ * quota_go_demote_ok - Check to see if it's ok to unlock a quota glock
+ * @gl: the glock
+ *
+ * Returns: 1 if it's ok
+ */
+
+static int quota_go_demote_ok(struct gfs2_glock *gl)
+{
+	return !atomic_read(&gl->gl_lvb_count);
+}
+
+const struct gfs2_glock_operations gfs2_meta_glops = {
+	.go_xmote_th = gfs2_glock_xmote_th,
+	.go_drop_th = gfs2_glock_drop_th,
+	.go_type = LM_TYPE_META,
+};
+
+const struct gfs2_glock_operations gfs2_inode_glops = {
+	.go_xmote_th = inode_go_xmote_th,
+	.go_xmote_bh = inode_go_xmote_bh,
+	.go_drop_th = inode_go_drop_th,
+	.go_sync = inode_go_sync,
+	.go_inval = inode_go_inval,
+	.go_demote_ok = inode_go_demote_ok,
+	.go_lock = inode_go_lock,
+	.go_unlock = inode_go_unlock,
+	.go_greedy = inode_greedy,
+	.go_type = LM_TYPE_INODE,
+};
+
+const struct gfs2_glock_operations gfs2_rgrp_glops = {
+	.go_xmote_th = gfs2_glock_xmote_th,
+	.go_drop_th = gfs2_glock_drop_th,
+	.go_sync = meta_go_sync,
+	.go_inval = meta_go_inval,
+	.go_demote_ok = rgrp_go_demote_ok,
+	.go_lock = rgrp_go_lock,
+	.go_unlock = rgrp_go_unlock,
+	.go_type = LM_TYPE_RGRP,
+};
+
+const struct gfs2_glock_operations gfs2_trans_glops = {
+	.go_xmote_th = trans_go_xmote_th,
+	.go_xmote_bh = trans_go_xmote_bh,
+	.go_drop_th = trans_go_drop_th,
+	.go_type = LM_TYPE_NONDISK,
+};
+
+const struct gfs2_glock_operations gfs2_iopen_glops = {
+	.go_xmote_th = gfs2_glock_xmote_th,
+	.go_drop_th = gfs2_glock_drop_th,
+	.go_type = LM_TYPE_IOPEN,
+};
+
+const struct gfs2_glock_operations gfs2_flock_glops = {
+	.go_xmote_th = gfs2_glock_xmote_th,
+	.go_drop_th = gfs2_glock_drop_th,
+	.go_type = LM_TYPE_FLOCK,
+};
+
+const struct gfs2_glock_operations gfs2_nondisk_glops = {
+	.go_xmote_th = gfs2_glock_xmote_th,
+	.go_drop_th = gfs2_glock_drop_th,
+	.go_type = LM_TYPE_NONDISK,
+};
+
+const struct gfs2_glock_operations gfs2_quota_glops = {
+	.go_xmote_th = gfs2_glock_xmote_th,
+	.go_drop_th = gfs2_glock_drop_th,
+	.go_demote_ok = quota_go_demote_ok,
+	.go_type = LM_TYPE_QUOTA,
+};
+
+const struct gfs2_glock_operations gfs2_journal_glops = {
+	.go_xmote_th = gfs2_glock_xmote_th,
+	.go_drop_th = gfs2_glock_drop_th,
+	.go_type = LM_TYPE_JOURNAL,
+};
+