Add the rt linux 4.1.3-rt3 as base
[kvmfornfv.git] / kernel / fs / gfs2 / glops.c
diff --git a/kernel/fs/gfs2/glops.c b/kernel/fs/gfs2/glops.c
new file mode 100644 (file)
index 0000000..fe91951
--- /dev/null
@@ -0,0 +1,616 @@
+/*
+ * Copyright (C) Sistina Software, Inc.  1997-2003 All rights reserved.
+ * Copyright (C) 2004-2008 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/spinlock.h>
+#include <linux/completion.h>
+#include <linux/buffer_head.h>
+#include <linux/gfs2_ondisk.h>
+#include <linux/bio.h>
+#include <linux/posix_acl.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"
+#include "dir.h"
+
+struct workqueue_struct *gfs2_freeze_wq;
+
+static void gfs2_ail_error(struct gfs2_glock *gl, const struct buffer_head *bh)
+{
+       fs_err(gl->gl_sbd, "AIL buffer %p: blocknr %llu state 0x%08lx mapping %p page state 0x%lx\n",
+              bh, (unsigned long long)bh->b_blocknr, bh->b_state,
+              bh->b_page->mapping, bh->b_page->flags);
+       fs_err(gl->gl_sbd, "AIL glock %u:%llu mapping %p\n",
+              gl->gl_name.ln_type, gl->gl_name.ln_number,
+              gfs2_glock2aspace(gl));
+       gfs2_lm_withdraw(gl->gl_sbd, "AIL error\n");
+}
+
+/**
+ * __gfs2_ail_flush - remove all buffers for a given lock from the AIL
+ * @gl: the glock
+ * @fsync: set when called from fsync (not all buffers will be clean)
+ *
+ * None of the buffers should be dirty, locked, or pinned.
+ */
+
+static void __gfs2_ail_flush(struct gfs2_glock *gl, bool fsync,
+                            unsigned int nr_revokes)
+{
+       struct gfs2_sbd *sdp = gl->gl_sbd;
+       struct list_head *head = &gl->gl_ail_list;
+       struct gfs2_bufdata *bd, *tmp;
+       struct buffer_head *bh;
+       const unsigned long b_state = (1UL << BH_Dirty)|(1UL << BH_Pinned)|(1UL << BH_Lock);
+
+       gfs2_log_lock(sdp);
+       spin_lock(&sdp->sd_ail_lock);
+       list_for_each_entry_safe_reverse(bd, tmp, head, bd_ail_gl_list) {
+               if (nr_revokes == 0)
+                       break;
+               bh = bd->bd_bh;
+               if (bh->b_state & b_state) {
+                       if (fsync)
+                               continue;
+                       gfs2_ail_error(gl, bh);
+               }
+               gfs2_trans_add_revoke(sdp, bd);
+               nr_revokes--;
+       }
+       GLOCK_BUG_ON(gl, !fsync && atomic_read(&gl->gl_ail_count));
+       spin_unlock(&sdp->sd_ail_lock);
+       gfs2_log_unlock(sdp);
+}
+
+
+static void gfs2_ail_empty_gl(struct gfs2_glock *gl)
+{
+       struct gfs2_sbd *sdp = gl->gl_sbd;
+       struct gfs2_trans tr;
+
+       memset(&tr, 0, sizeof(tr));
+       INIT_LIST_HEAD(&tr.tr_buf);
+       INIT_LIST_HEAD(&tr.tr_databuf);
+       tr.tr_revokes = atomic_read(&gl->gl_ail_count);
+
+       if (!tr.tr_revokes)
+               return;
+
+       /* A shortened, inline version of gfs2_trans_begin()
+         * tr->alloced is not set since the transaction structure is
+         * on the stack */
+       tr.tr_reserved = 1 + gfs2_struct2blk(sdp, tr.tr_revokes, sizeof(u64));
+       tr.tr_ip = _RET_IP_;
+       if (gfs2_log_reserve(sdp, tr.tr_reserved) < 0)
+               return;
+       WARN_ON_ONCE(current->journal_info);
+       current->journal_info = &tr;
+
+       __gfs2_ail_flush(gl, 0, tr.tr_revokes);
+
+       gfs2_trans_end(sdp);
+       gfs2_log_flush(sdp, NULL, NORMAL_FLUSH);
+}
+
+void gfs2_ail_flush(struct gfs2_glock *gl, bool fsync)
+{
+       struct gfs2_sbd *sdp = gl->gl_sbd;
+       unsigned int revokes = atomic_read(&gl->gl_ail_count);
+       unsigned int max_revokes = (sdp->sd_sb.sb_bsize - sizeof(struct gfs2_log_descriptor)) / sizeof(u64);
+       int ret;
+
+       if (!revokes)
+               return;
+
+       while (revokes > max_revokes)
+               max_revokes += (sdp->sd_sb.sb_bsize - sizeof(struct gfs2_meta_header)) / sizeof(u64);
+
+       ret = gfs2_trans_begin(sdp, 0, max_revokes);
+       if (ret)
+               return;
+       __gfs2_ail_flush(gl, fsync, max_revokes);
+       gfs2_trans_end(sdp);
+       gfs2_log_flush(sdp, NULL, NORMAL_FLUSH);
+}
+
+/**
+ * rgrp_go_sync - sync out the metadata for this glock
+ * @gl: the glock
+ *
+ * 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 rgrp_go_sync(struct gfs2_glock *gl)
+{
+       struct gfs2_sbd *sdp = gl->gl_sbd;
+       struct address_space *mapping = &sdp->sd_aspace;
+       struct gfs2_rgrpd *rgd;
+       int error;
+
+       if (!test_and_clear_bit(GLF_DIRTY, &gl->gl_flags))
+               return;
+       GLOCK_BUG_ON(gl, gl->gl_state != LM_ST_EXCLUSIVE);
+
+       gfs2_log_flush(sdp, gl, NORMAL_FLUSH);
+       filemap_fdatawrite_range(mapping, gl->gl_vm.start, gl->gl_vm.end);
+       error = filemap_fdatawait_range(mapping, gl->gl_vm.start, gl->gl_vm.end);
+       mapping_set_error(mapping, error);
+       gfs2_ail_empty_gl(gl);
+
+       spin_lock(&gl->gl_spin);
+       rgd = gl->gl_object;
+       if (rgd)
+               gfs2_free_clones(rgd);
+       spin_unlock(&gl->gl_spin);
+}
+
+/**
+ * rgrp_go_inval - invalidate the metadata for this glock
+ * @gl: the glock
+ * @flags:
+ *
+ * We never used LM_ST_DEFERRED with resource groups, so that we
+ * should always see the metadata flag set here.
+ *
+ */
+
+static void rgrp_go_inval(struct gfs2_glock *gl, int flags)
+{
+       struct gfs2_sbd *sdp = gl->gl_sbd;
+       struct address_space *mapping = &sdp->sd_aspace;
+
+       WARN_ON_ONCE(!(flags & DIO_METADATA));
+       gfs2_assert_withdraw(sdp, !atomic_read(&gl->gl_ail_count));
+       truncate_inode_pages_range(mapping, gl->gl_vm.start, gl->gl_vm.end);
+
+       if (gl->gl_object) {
+               struct gfs2_rgrpd *rgd = (struct gfs2_rgrpd *)gl->gl_object;
+               rgd->rd_flags &= ~GFS2_RDF_UPTODATE;
+       }
+}
+
+/**
+ * inode_go_sync - Sync the dirty data and/or metadata for an inode glock
+ * @gl: the glock protecting the inode
+ *
+ */
+
+static void inode_go_sync(struct gfs2_glock *gl)
+{
+       struct gfs2_inode *ip = gl->gl_object;
+       struct address_space *metamapping = gfs2_glock2aspace(gl);
+       int error;
+
+       if (ip && !S_ISREG(ip->i_inode.i_mode))
+               ip = NULL;
+       if (ip) {
+               if (test_and_clear_bit(GIF_SW_PAGED, &ip->i_flags))
+                       unmap_shared_mapping_range(ip->i_inode.i_mapping, 0, 0);
+               inode_dio_wait(&ip->i_inode);
+       }
+       if (!test_and_clear_bit(GLF_DIRTY, &gl->gl_flags))
+               return;
+
+       GLOCK_BUG_ON(gl, gl->gl_state != LM_ST_EXCLUSIVE);
+
+       gfs2_log_flush(gl->gl_sbd, gl, NORMAL_FLUSH);
+       filemap_fdatawrite(metamapping);
+       if (ip) {
+               struct address_space *mapping = ip->i_inode.i_mapping;
+               filemap_fdatawrite(mapping);
+               error = filemap_fdatawait(mapping);
+               mapping_set_error(mapping, error);
+       }
+       error = filemap_fdatawait(metamapping);
+       mapping_set_error(metamapping, error);
+       gfs2_ail_empty_gl(gl);
+       /*
+        * Writeback of the data mapping may cause the dirty flag to be set
+        * so we have to clear it again here.
+        */
+       smp_mb__before_atomic();
+       clear_bit(GLF_DIRTY, &gl->gl_flags);
+}
+
+/**
+ * inode_go_inval - prepare a inode glock to be released
+ * @gl: the glock
+ * @flags:
+ *
+ * Normally we invalidate everything, but if we are moving into
+ * LM_ST_DEFERRED from LM_ST_SHARED or LM_ST_EXCLUSIVE then we
+ * can keep hold of the metadata, since it won't have changed.
+ *
+ */
+
+static void inode_go_inval(struct gfs2_glock *gl, int flags)
+{
+       struct gfs2_inode *ip = gl->gl_object;
+
+       gfs2_assert_withdraw(gl->gl_sbd, !atomic_read(&gl->gl_ail_count));
+
+       if (flags & DIO_METADATA) {
+               struct address_space *mapping = gfs2_glock2aspace(gl);
+               truncate_inode_pages(mapping, 0);
+               if (ip) {
+                       set_bit(GIF_INVALID, &ip->i_flags);
+                       forget_all_cached_acls(&ip->i_inode);
+                       gfs2_dir_hash_inval(ip);
+               }
+       }
+
+       if (ip == GFS2_I(gl->gl_sbd->sd_rindex)) {
+               gfs2_log_flush(gl->gl_sbd, NULL, NORMAL_FLUSH);
+               gl->gl_sbd->sd_rindex_uptodate = 0;
+       }
+       if (ip && S_ISREG(ip->i_inode.i_mode))
+               truncate_inode_pages(ip->i_inode.i_mapping, 0);
+}
+
+/**
+ * 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(const struct gfs2_glock *gl)
+{
+       struct gfs2_sbd *sdp = gl->gl_sbd;
+       struct gfs2_holder *gh;
+
+       if (sdp->sd_jindex == gl->gl_object || sdp->sd_rindex == gl->gl_object)
+               return 0;
+
+       if (!list_empty(&gl->gl_holders)) {
+               gh = list_entry(gl->gl_holders.next, struct gfs2_holder, gh_list);
+               if (gh->gh_list.next != &gl->gl_holders)
+                       return 0;
+       }
+
+       return 1;
+}
+
+/**
+ * gfs2_set_nlink - Set the inode's link count based on on-disk info
+ * @inode: The inode in question
+ * @nlink: The link count
+ *
+ * If the link count has hit zero, it must never be raised, whatever the
+ * on-disk inode might say. When new struct inodes are created the link
+ * count is set to 1, so that we can safely use this test even when reading
+ * in on disk information for the first time.
+ */
+
+static void gfs2_set_nlink(struct inode *inode, u32 nlink)
+{
+       /*
+        * We will need to review setting the nlink count here in the
+        * light of the forthcoming ro bind mount work. This is a reminder
+        * to do that.
+        */
+       if ((inode->i_nlink != nlink) && (inode->i_nlink != 0)) {
+               if (nlink == 0)
+                       clear_nlink(inode);
+               else
+                       set_nlink(inode, nlink);
+       }
+}
+
+static int gfs2_dinode_in(struct gfs2_inode *ip, const void *buf)
+{
+       const struct gfs2_dinode *str = buf;
+       struct timespec atime;
+       u16 height, depth;
+
+       if (unlikely(ip->i_no_addr != be64_to_cpu(str->di_num.no_addr)))
+               goto corrupt;
+       ip->i_no_formal_ino = be64_to_cpu(str->di_num.no_formal_ino);
+       ip->i_inode.i_mode = be32_to_cpu(str->di_mode);
+       ip->i_inode.i_rdev = 0;
+       switch (ip->i_inode.i_mode & S_IFMT) {
+       case S_IFBLK:
+       case S_IFCHR:
+               ip->i_inode.i_rdev = MKDEV(be32_to_cpu(str->di_major),
+                                          be32_to_cpu(str->di_minor));
+               break;
+       };
+
+       i_uid_write(&ip->i_inode, be32_to_cpu(str->di_uid));
+       i_gid_write(&ip->i_inode, be32_to_cpu(str->di_gid));
+       gfs2_set_nlink(&ip->i_inode, be32_to_cpu(str->di_nlink));
+       i_size_write(&ip->i_inode, be64_to_cpu(str->di_size));
+       gfs2_set_inode_blocks(&ip->i_inode, be64_to_cpu(str->di_blocks));
+       atime.tv_sec = be64_to_cpu(str->di_atime);
+       atime.tv_nsec = be32_to_cpu(str->di_atime_nsec);
+       if (timespec_compare(&ip->i_inode.i_atime, &atime) < 0)
+               ip->i_inode.i_atime = atime;
+       ip->i_inode.i_mtime.tv_sec = be64_to_cpu(str->di_mtime);
+       ip->i_inode.i_mtime.tv_nsec = be32_to_cpu(str->di_mtime_nsec);
+       ip->i_inode.i_ctime.tv_sec = be64_to_cpu(str->di_ctime);
+       ip->i_inode.i_ctime.tv_nsec = be32_to_cpu(str->di_ctime_nsec);
+
+       ip->i_goal = be64_to_cpu(str->di_goal_meta);
+       ip->i_generation = be64_to_cpu(str->di_generation);
+
+       ip->i_diskflags = be32_to_cpu(str->di_flags);
+       ip->i_eattr = be64_to_cpu(str->di_eattr);
+       /* i_diskflags and i_eattr must be set before gfs2_set_inode_flags() */
+       gfs2_set_inode_flags(&ip->i_inode);
+       height = be16_to_cpu(str->di_height);
+       if (unlikely(height > GFS2_MAX_META_HEIGHT))
+               goto corrupt;
+       ip->i_height = (u8)height;
+
+       depth = be16_to_cpu(str->di_depth);
+       if (unlikely(depth > GFS2_DIR_MAX_DEPTH))
+               goto corrupt;
+       ip->i_depth = (u8)depth;
+       ip->i_entries = be32_to_cpu(str->di_entries);
+
+       if (S_ISREG(ip->i_inode.i_mode))
+               gfs2_set_aops(&ip->i_inode);
+
+       return 0;
+corrupt:
+       gfs2_consist_inode(ip);
+       return -EIO;
+}
+
+/**
+ * gfs2_inode_refresh - Refresh the incore copy of the dinode
+ * @ip: The GFS2 inode
+ *
+ * Returns: errno
+ */
+
+int gfs2_inode_refresh(struct gfs2_inode *ip)
+{
+       struct buffer_head *dibh;
+       int error;
+
+       error = gfs2_meta_inode_buffer(ip, &dibh);
+       if (error)
+               return error;
+
+       error = gfs2_dinode_in(ip, dibh->b_data);
+       brelse(dibh);
+       clear_bit(GIF_INVALID, &ip->i_flags);
+
+       return error;
+}
+
+/**
+ * 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_sbd *sdp = gl->gl_sbd;
+       struct gfs2_inode *ip = gl->gl_object;
+       int error = 0;
+
+       if (!ip || (gh->gh_flags & GL_SKIP))
+               return 0;
+
+       if (test_bit(GIF_INVALID, &ip->i_flags)) {
+               error = gfs2_inode_refresh(ip);
+               if (error)
+                       return error;
+       }
+
+       if (gh->gh_state != LM_ST_DEFERRED)
+               inode_dio_wait(&ip->i_inode);
+
+       if ((ip->i_diskflags & GFS2_DIF_TRUNC_IN_PROG) &&
+           (gl->gl_state == LM_ST_EXCLUSIVE) &&
+           (gh->gh_state == LM_ST_EXCLUSIVE)) {
+               spin_lock(&sdp->sd_trunc_lock);
+               if (list_empty(&ip->i_trunc_list))
+                       list_add(&sdp->sd_trunc_list, &ip->i_trunc_list);
+               spin_unlock(&sdp->sd_trunc_lock);
+               wake_up(&sdp->sd_quota_wait);
+               return 1;
+       }
+
+       return error;
+}
+
+/**
+ * inode_go_dump - print information about an inode
+ * @seq: The iterator
+ * @ip: the inode
+ *
+ */
+
+static void inode_go_dump(struct seq_file *seq, const struct gfs2_glock *gl)
+{
+       const struct gfs2_inode *ip = gl->gl_object;
+       if (ip == NULL)
+               return;
+       gfs2_print_dbg(seq, " I: n:%llu/%llu t:%u f:0x%02lx d:0x%08x s:%llu\n",
+                 (unsigned long long)ip->i_no_formal_ino,
+                 (unsigned long long)ip->i_no_addr,
+                 IF2DT(ip->i_inode.i_mode), ip->i_flags,
+                 (unsigned int)ip->i_diskflags,
+                 (unsigned long long)i_size_read(&ip->i_inode));
+}
+
+/**
+ * freeze_go_sync - promote/demote the freeze glock
+ * @gl: the glock
+ * @state: the requested state
+ * @flags:
+ *
+ */
+
+static void freeze_go_sync(struct gfs2_glock *gl)
+{
+       int error = 0;
+       struct gfs2_sbd *sdp = gl->gl_sbd;
+
+       if (gl->gl_state == LM_ST_SHARED &&
+           test_bit(SDF_JOURNAL_LIVE, &sdp->sd_flags)) {
+               atomic_set(&sdp->sd_freeze_state, SFS_STARTING_FREEZE);
+               error = freeze_super(sdp->sd_vfs);
+               if (error) {
+                       printk(KERN_INFO "GFS2: couldn't freeze filesystem: %d\n", error);
+                       gfs2_assert_withdraw(sdp, 0);
+               }
+               queue_work(gfs2_freeze_wq, &sdp->sd_freeze_work);
+               gfs2_log_flush(sdp, NULL, FREEZE_FLUSH);
+       }
+}
+
+/**
+ * freeze_go_xmote_bh - After promoting/demoting the freeze glock
+ * @gl: the glock
+ *
+ */
+
+static int freeze_go_xmote_bh(struct gfs2_glock *gl, struct gfs2_holder *gh)
+{
+       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_host head;
+       int error;
+
+       if (test_bit(SDF_JOURNAL_LIVE, &sdp->sd_flags)) {
+               j_gl->gl_ops->go_inval(j_gl, DIO_METADATA);
+
+               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);
+               }
+       }
+       return 0;
+}
+
+/**
+ * trans_go_demote_ok
+ * @gl: the glock
+ *
+ * Always returns 0
+ */
+
+static int freeze_go_demote_ok(const struct gfs2_glock *gl)
+{
+       return 0;
+}
+
+/**
+ * iopen_go_callback - schedule the dcache entry for the inode to be deleted
+ * @gl: the glock
+ *
+ * gl_spin lock is held while calling this
+ */
+static void iopen_go_callback(struct gfs2_glock *gl, bool remote)
+{
+       struct gfs2_inode *ip = (struct gfs2_inode *)gl->gl_object;
+       struct gfs2_sbd *sdp = gl->gl_sbd;
+
+       if (!remote || (sdp->sd_vfs->s_flags & MS_RDONLY))
+               return;
+
+       if (gl->gl_demote_state == LM_ST_UNLOCKED &&
+           gl->gl_state == LM_ST_SHARED && ip) {
+               gl->gl_lockref.count++;
+               if (queue_work(gfs2_delete_workqueue, &gl->gl_delete) == 0)
+                       gl->gl_lockref.count--;
+       }
+}
+
+const struct gfs2_glock_operations gfs2_meta_glops = {
+       .go_type = LM_TYPE_META,
+};
+
+const struct gfs2_glock_operations gfs2_inode_glops = {
+       .go_sync = inode_go_sync,
+       .go_inval = inode_go_inval,
+       .go_demote_ok = inode_go_demote_ok,
+       .go_lock = inode_go_lock,
+       .go_dump = inode_go_dump,
+       .go_type = LM_TYPE_INODE,
+       .go_flags = GLOF_ASPACE,
+};
+
+const struct gfs2_glock_operations gfs2_rgrp_glops = {
+       .go_sync = rgrp_go_sync,
+       .go_inval = rgrp_go_inval,
+       .go_lock = gfs2_rgrp_go_lock,
+       .go_unlock = gfs2_rgrp_go_unlock,
+       .go_dump = gfs2_rgrp_dump,
+       .go_type = LM_TYPE_RGRP,
+       .go_flags = GLOF_LVB,
+};
+
+const struct gfs2_glock_operations gfs2_freeze_glops = {
+       .go_sync = freeze_go_sync,
+       .go_xmote_bh = freeze_go_xmote_bh,
+       .go_demote_ok = freeze_go_demote_ok,
+       .go_type = LM_TYPE_NONDISK,
+};
+
+const struct gfs2_glock_operations gfs2_iopen_glops = {
+       .go_type = LM_TYPE_IOPEN,
+       .go_callback = iopen_go_callback,
+};
+
+const struct gfs2_glock_operations gfs2_flock_glops = {
+       .go_type = LM_TYPE_FLOCK,
+};
+
+const struct gfs2_glock_operations gfs2_nondisk_glops = {
+       .go_type = LM_TYPE_NONDISK,
+};
+
+const struct gfs2_glock_operations gfs2_quota_glops = {
+       .go_type = LM_TYPE_QUOTA,
+       .go_flags = GLOF_LVB,
+};
+
+const struct gfs2_glock_operations gfs2_journal_glops = {
+       .go_type = LM_TYPE_JOURNAL,
+};
+
+const struct gfs2_glock_operations *gfs2_glops_list[] = {
+       [LM_TYPE_META] = &gfs2_meta_glops,
+       [LM_TYPE_INODE] = &gfs2_inode_glops,
+       [LM_TYPE_RGRP] = &gfs2_rgrp_glops,
+       [LM_TYPE_IOPEN] = &gfs2_iopen_glops,
+       [LM_TYPE_FLOCK] = &gfs2_flock_glops,
+       [LM_TYPE_NONDISK] = &gfs2_nondisk_glops,
+       [LM_TYPE_QUOTA] = &gfs2_quota_glops,
+       [LM_TYPE_JOURNAL] = &gfs2_journal_glops,
+};
+