[PATCH 49/67] aufs inode operations (del entry)
From: hooanon05
Date: Fri May 16 2008 - 11:06:36 EST
From: Junjiro Okajima <hooanon05@xxxxxxxxxxx>
initial commit
aufs inode operations (del entry)
Signed-off-by: Junjiro Okajima <hooanon05@xxxxxxxxxxx>
---
fs/aufs/i_op_del.c | 582 ++++++++++++++++++++++++++++++++++++++++++++++++++++
1 files changed, 582 insertions(+), 0 deletions(-)
diff --git a/fs/aufs/i_op_del.c b/fs/aufs/i_op_del.c
new file mode 100644
index 0000000..5b84cca
--- /dev/null
+++ b/fs/aufs/i_op_del.c
@@ -0,0 +1,582 @@
+/*
+ * Copyright (C) 2005-2008 Junjiro Okajima
+ *
+ * This program, aufs 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; either version 2 of the License, or
+ * (at your option) any later version.
+ *
+ * This program 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 this program; if not, write to the Free Software
+ * Foundation, Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA
+ */
+
+/*
+ * inode operations (del entry)
+ *
+ * $Id: i_op_del.c,v 1.4 2008/05/04 23:54:53 sfjro Exp $
+ */
+
+#include "aufs.h"
+
+/* returns,
+ * 0: wh is unnecessary
+ * plus: wh is necessary
+ * minus: error
+ */
+int au_wr_dir_need_wh(struct dentry *dentry, int isdir, aufs_bindex_t *bcpup,
+ struct dentry *locked)
+{
+ int need_wh, err;
+ aufs_bindex_t bstart;
+ struct dentry *h_dentry;
+ struct super_block *sb;
+
+ LKTRTrace("%.*s, isdir %d, *bcpup %d, locked %p\n",
+ AuDLNPair(dentry), isdir, *bcpup, locked);
+ sb = dentry->d_sb;
+
+ bstart = au_dbstart(dentry);
+ LKTRTrace("bcpup %d, bstart %d\n", *bcpup, bstart);
+ h_dentry = au_h_dptr(dentry, bstart);
+ if (*bcpup < 0) {
+ *bcpup = bstart;
+ if (au_test_ro(sb, bstart, dentry->d_inode)) {
+ err = AuWbrCopyup(au_sbi(sb), dentry);
+ *bcpup = err;
+ //err = -1;
+ if (unlikely(err < 0))
+ goto out;
+ }
+ } else
+ AuDebugOn(bstart < *bcpup
+ || au_test_ro(sb, *bcpup, dentry->d_inode));
+ LKTRTrace("bcpup %d, bstart %d\n", *bcpup, bstart);
+
+ if (*bcpup != bstart) {
+ err = au_cpup_dirs(dentry, *bcpup, locked);
+ //err = -1;
+ if (unlikely(err))
+ goto out;
+ need_wh = 1;
+ } else {
+ //struct nameidata nd;
+ aufs_bindex_t old_bend, new_bend, bdiropq = -1;
+ old_bend = au_dbend(dentry);
+ if (isdir) {
+ bdiropq = au_dbdiropq(dentry);
+ au_set_dbdiropq(dentry, -1);
+ }
+ need_wh = au_lkup_dentry(dentry, bstart + 1, /*type*/0,
+ /*nd*/NULL);
+ err = need_wh;
+ //err = -1;
+ if (isdir)
+ au_set_dbdiropq(dentry, bdiropq);
+ if (unlikely(err < 0))
+ goto out;
+ new_bend = au_dbend(dentry);
+ if (!need_wh && old_bend != new_bend) {
+ au_set_h_dptr(dentry, new_bend, NULL);
+ au_set_dbend(dentry, old_bend);
+#if 0 // remove this?
+ } else if (!au_h_dptr(dentry, new_bend)->d_inode) {
+ LKTRTrace("negative\n");
+ au_set_h_dptr(dentry, new_bend, NULL);
+ au_set_dbend(dentry, old_bend);
+ need_wh = 0;
+#endif
+ }
+ }
+ LKTRTrace("need_wh %d\n", need_wh);
+ err = need_wh;
+
+ out:
+ AuTraceErr(err);
+ return err;
+}
+
+/*
+ * simple tests for the removal inode operations.
+ * following the checks in vfs, plus the parent-child relationship.
+ */
+int au_may_del(struct dentry *dentry, aufs_bindex_t bindex,
+ struct dentry *h_parent, int isdir, struct au_ndx *ndx)
+{
+ int err, exist;
+ struct super_block *sb;
+ struct dentry *h_dentry;
+ struct inode *h_inode;
+ umode_t h_mode;
+
+ LKTRTrace("%.*s/%.*s, b%d, dir %d\n",
+ AuDLNPair(h_parent), AuDLNPair(dentry), bindex, isdir);
+
+ sb = dentry->d_sb;
+ exist = !!dentry->d_inode;
+ h_dentry = au_h_dptr(dentry, bindex);
+ h_inode = h_dentry->d_inode;
+ if (exist) {
+ err = -ENOENT;
+ if (unlikely(!h_inode || !h_inode->i_nlink))
+ goto out;
+
+ h_mode = h_inode->i_mode;
+ if (!isdir) {
+ err = -EISDIR;
+ if (unlikely(S_ISDIR(h_mode)))
+ goto out;
+ } else if (unlikely(!S_ISDIR(h_mode))) {
+ err = -ENOTDIR;
+ goto out;
+ }
+ } else {
+ /* rename(2) case */
+ err = -EIO;
+ if (unlikely(h_inode))
+ goto out;
+ }
+
+ err = -ENOENT;
+ /* expected parent dir is locked */
+ if (unlikely(h_parent != h_dentry->d_parent))
+ goto out;
+ err = 0;
+
+ /*
+ * some filesystem may unlink a dir and corrupt its consistency.
+ * so let's try heavy test.
+ */
+ if (1 /*unlikely(au_opt_test(au_mntflags(sb), UDBA_INOTIFY))*/) {
+ struct dentry *h_latest;
+ struct qstr *qstr = &dentry->d_name;
+
+ err = -EACCES;
+ if (unlikely(au_test_h_perm(h_parent->d_inode,
+ MAY_EXEC | MAY_WRITE,
+ au_ftest_ndx(ndx->flags, DLGT))))
+ goto out;
+
+ h_latest = au_sio_lkup_one(qstr->name, h_parent, qstr->len,
+ ndx);
+ //err = PTR_ERR(h_latest);
+ err = -EIO;
+ if (IS_ERR(h_latest))
+ goto out;
+ dput(h_latest);
+ if (h_latest == h_dentry)
+ err = 0;
+ }
+
+ out:
+ AuTraceErr(err);
+ return err;
+}
+
+static struct dentry *
+lock_hdir_create_wh(struct dentry *dentry, int isdir, aufs_bindex_t *rbcpup,
+ struct au_dtime *dt)
+{
+ struct dentry *wh_dentry;
+ int err, need_wh;
+ struct dentry *h_parent, *parent, *gparent;
+ struct inode *dir, *h_dir, *gdir;
+ struct au_ndx ndx;
+ struct super_block *sb;
+ struct au_hinode *hgdir;
+ aufs_bindex_t bcpup;
+ unsigned int mnt_flags;
+
+ LKTRTrace("%.*s, isdir %d\n", AuDLNPair(dentry), isdir);
+
+ need_wh = au_wr_dir_need_wh(dentry, isdir, rbcpup, NULL);
+ err = need_wh;
+ //err = -1;
+ wh_dentry = ERR_PTR(err);
+ if (unlikely(err < 0))
+ goto out;
+
+ //todo: meaningless lock if CONFIG_AUFS_DEBUG is disabled.
+ hgdir = NULL;
+ bcpup = *rbcpup;
+ sb = dentry->d_sb;
+ mnt_flags = au_mntflags(sb);
+ parent = dentry->d_parent; /* dir inode is locked */
+ if (unlikely(au_opt_test(mnt_flags, UDBA_INOTIFY)
+ && !IS_ROOT(parent))) {
+ gparent = dget_parent(parent);
+ gdir = gparent->d_inode;
+ ii_read_lock_parent2(gdir);
+ hgdir = au_hi(gdir, bcpup);
+ ii_read_unlock(gdir);
+ dput(gparent);
+ }
+ dir = parent->d_inode;
+ IMustLock(dir);
+ h_parent = au_h_dptr(parent, bcpup);
+ h_dir = h_parent->d_inode;
+
+ AuDbgSleep_UdbaRace();
+ au_hdir_lock(h_dir, dir, bcpup);
+ //todo: revalidate the lower dentry?
+
+ if (!au_opt_test(mnt_flags, UDBA_NONE) && au_dbstart(dentry) == bcpup) {
+ ndx.nfsmnt = au_nfsmnt(sb, bcpup);
+ ndx.flags = 0;
+ if (unlikely(au_opt_test_dlgt(mnt_flags)))
+ au_fset_ndx(ndx.flags, DLGT);
+ ndx.nd = NULL;
+ //ndx.br = au_sbr(sb, bcpup);
+ //ndx.nd_file = NULL;
+ err = au_may_del(dentry, bcpup, h_parent, isdir, &ndx);
+ wh_dentry = ERR_PTR(err);
+ if (unlikely(err))
+ goto out_dir;
+ }
+
+ au_dtime_store(dt, parent, h_parent, hgdir);
+ wh_dentry = NULL;
+ if (!need_wh)
+ goto out; /* success, no need to create whiteout */
+
+ ndx.nfsmnt = au_nfsmnt(sb, bcpup);
+ ndx.flags = 0;
+ if (unlikely(au_opt_test_dlgt(mnt_flags)))
+ au_fset_ndx(ndx.flags, DLGT);
+ ndx.nd = NULL;
+ //ndx.br = NULL;
+ wh_dentry = au_wh_create(dir, dentry, bcpup, h_parent, &ndx);
+ //wh_dentry = ERR_PTR(-1);
+ if (!IS_ERR(wh_dentry))
+ goto out; /* success */
+ /* returns with the parent is locked and wh_dentry is DGETed */
+
+ out_dir:
+ au_hdir_unlock(h_dir, dir, bcpup);
+ out:
+ AuTraceErrPtr(wh_dentry);
+ return wh_dentry;
+}
+
+static int renwh_and_rmdir(struct dentry *dentry, aufs_bindex_t bindex,
+ struct au_nhash *whlist, struct inode *dir)
+{
+ int rmdir_later, err;
+ struct dentry *h_dentry;
+ struct inode *inode, *h_inode;
+ struct super_block *sb;
+
+ LKTRTrace("%.*s, b%d\n", AuDLNPair(dentry), bindex);
+
+ inode = NULL;
+ h_inode = NULL;
+ sb = dentry->d_sb;
+ if (unlikely(au_opt_test(au_mntflags(sb), UDBA_INOTIFY))) {
+ inode = dentry->d_inode;
+ h_inode = au_h_iptr(inode, bindex);
+ au_hdir2_lock(h_inode, inode, bindex);
+ }
+ err = au_whtmp_ren(dir, dentry, bindex, /*noself*/1);
+ if (unlikely(inode))
+ au_hdir_unlock(h_inode, inode, bindex);
+ //err = -1;
+ if (unlikely(err))
+ goto out;
+
+ h_dentry = au_h_dptr(dentry, bindex);
+ if (!au_test_nfs(h_dentry->d_sb)) {
+ const int dirwh = au_sbi(sb)->si_dirwh;
+ rmdir_later = (dirwh <= 1);
+ if (!rmdir_later)
+ rmdir_later = au_nhash_test_longer_wh(whlist, bindex,
+ dirwh);
+ if (rmdir_later)
+ return rmdir_later;
+ }
+
+ err = au_whtmp_rmdir(h_dentry, whlist, bindex, dir, dentry->d_inode,
+ /*noself*/1);
+ //err = -1;
+ if (unlikely(err)) {
+ AuIOErr("rmdir %.*s, b%d failed, %d. ignored\n",
+ AuDLNPair(h_dentry), bindex, err);
+ err = 0;
+ }
+
+ out:
+ AuTraceErr(err);
+ return err;
+}
+
+static void epilog(struct inode *dir, struct dentry *dentry,
+ aufs_bindex_t bindex)
+{
+ //todo: unnecessary?
+ d_drop(dentry);
+ dentry->d_inode->i_ctime = dir->i_ctime;
+
+ if (atomic_read(&dentry->d_count) == 1) {
+ au_set_h_dptr(dentry, au_dbstart(dentry), NULL);
+ au_update_dbstart(dentry);
+ }
+ if (au_ibstart(dir) == bindex)
+ au_cpup_attr_timesizes(dir);
+ dir->i_version++;
+}
+
+/* revert flags */
+#define AuRev_DLGT 1
+#define au_ftest_rev(flags, name) ((flags) & AuRev_##name)
+#define au_fset_rev(flags, name) { (flags) |= AuRev_##name; }
+#define au_fclr_rev(flags, name) { (flags) &= ~AuRev_##name; }
+#ifndef CONFIG_AUFS_DLGT
+#undef AuRev_DLGT
+#define AuRev_DLGT 0
+#endif
+
+static int do_revert(int err, struct dentry *wh_dentry, struct dentry *dentry,
+ aufs_bindex_t bwh, struct au_dtime *dt, unsigned int flags)
+{
+ int rerr;
+ struct inode *dir;
+
+ dir = wh_dentry->d_parent->d_inode; /* dir inode is locked */
+ IMustLock(dir);
+ rerr = au_wh_unlink_dentry(dir, wh_dentry, dentry, dir,
+ au_ftest_rev(flags, DLGT));
+ //rerr = -1;
+ if (!rerr) {
+ au_set_dbwh(dentry, bwh);
+ au_dtime_revert(dt);
+ return 0;
+ }
+
+ AuIOErr("%.*s reverting whiteout failed(%d, %d)\n",
+ AuDLNPair(dentry), err, rerr);
+ return -EIO;
+}
+
+/* ---------------------------------------------------------------------- */
+
+int aufs_unlink(struct inode *dir, struct dentry *dentry)
+{
+ int err, dlgt;
+ struct inode *inode, *h_dir;
+ struct dentry *parent, *wh_dentry, *h_dentry;
+ struct au_dtime dt;
+ aufs_bindex_t bwh, bindex, bstart;
+ struct super_block *sb;
+ struct vfsub_args vargs;
+
+ LKTRTrace("i%lu, %.*s\n", dir->i_ino, AuDLNPair(dentry));
+ IMustLock(dir);
+ inode = dentry->d_inode;
+ if (unlikely(!inode))
+ return -ENOENT; /* possible? */
+ IMustLock(inode);
+
+ aufs_read_lock(dentry, AuLock_DW);
+ parent = dentry->d_parent; /* dir inode is locked */
+ di_write_lock_parent(parent);
+
+ bstart = au_dbstart(dentry);
+ bwh = au_dbwh(dentry);
+ bindex = -1;
+ wh_dentry = lock_hdir_create_wh(dentry, /*isdir*/0, &bindex, &dt);
+ //wh_dentry = ERR_PTR(-1);
+ err = PTR_ERR(wh_dentry);
+ if (IS_ERR(wh_dentry))
+ goto out;
+
+ sb = dir->i_sb;
+ dlgt = !!au_opt_test_dlgt(au_mntflags(sb));
+ AuDebugOn(au_dbstart(dentry) != bstart);
+ h_dentry = au_h_dptr(dentry, bstart);
+ dget(h_dentry);
+
+ if (bindex == bstart) {
+ vfsub_args_init(&vargs, NULL, dlgt, 0);
+ h_dir = h_dentry->d_parent->d_inode; /* dir inode is locked */
+ IMustLock(h_dir);
+ err = vfsub_unlink(h_dir, h_dentry, &vargs);
+ //err = -1;
+ } else {
+ /* dir inode is locked */
+ AuDebugOn(!wh_dentry
+ || wh_dentry->d_parent != au_h_dptr(parent, bindex));
+ h_dir = wh_dentry->d_parent->d_inode;
+ IMustLock(h_dir);
+ err = 0;
+ }
+
+ if (!err) {
+ drop_nlink(inode);
+#if 0 //todo: update plink
+ if (unlikely(!inode->i_nlink
+ && au_plink_test(sb, inode)
+ /* && atomic_read(&inode->i_count) == 2) */)) {
+ au_debug_on();
+ DbgInode(inode);
+ au_debug_off();
+ }
+#endif
+ epilog(dir, dentry, bindex);
+
+ /* update target timestamps */
+ if (bindex == bstart) {
+ au_update_fuse_h_inode(NULL, h_dentry); /*ignore*/
+ inode->i_ctime = h_dentry->d_inode->i_ctime;
+ } else
+ //todo: this timestamp may be reverted later
+ inode->i_ctime = h_dir->i_ctime;
+ goto out_unlock; /* success */
+ }
+
+ /* revert */
+ if (wh_dentry) {
+ int rerr;
+ unsigned int rev_flags;
+
+ rev_flags = 0;
+ if (unlikely(dlgt))
+ au_fset_rev(rev_flags, DLGT);
+ rerr = do_revert(err, wh_dentry, dentry, bwh, &dt, rev_flags);
+ if (rerr)
+ err = rerr;
+ }
+
+ out_unlock:
+ au_hdir_unlock(h_dir, dir, bindex);
+ dput(wh_dentry);
+ dput(h_dentry);
+ out:
+ di_write_unlock(parent);
+ aufs_read_unlock(dentry, AuLock_DW);
+ AuTraceErr(err);
+ return err;
+}
+
+int aufs_rmdir(struct inode *dir, struct dentry *dentry)
+{
+ int err, rmdir_later;
+ struct inode *inode, *h_dir;
+ struct dentry *parent, *wh_dentry, *h_dentry;
+ struct au_dtime dt;
+ aufs_bindex_t bwh, bindex, bstart;
+ struct au_whtmp_rmdir_args *args;
+ struct au_nhash *whlist;
+ struct super_block *sb;
+ unsigned int mnt_flags;
+
+ LKTRTrace("i%lu, %.*s\n", dir->i_ino, AuDLNPair(dentry));
+ IMustLock(dir);
+ inode = dentry->d_inode;
+ if (unlikely(!inode))
+ return -ENOENT; /* possible? */
+ IMustLock(inode);
+
+ whlist = au_nhash_new(GFP_TEMPORARY);
+ err = PTR_ERR(whlist);
+ if (IS_ERR(whlist))
+ goto out;
+
+ err = -ENOMEM;
+ args = kmalloc(sizeof(*args), GFP_TEMPORARY);
+ //args = NULL;
+ if (unlikely(!args))
+ goto out_whlist;
+
+ aufs_read_lock(dentry, AuLock_DW);
+ parent = dentry->d_parent; /* dir inode is locked */
+ di_write_lock_parent(parent);
+ err = au_test_empty(dentry, whlist);
+ //err = -1;
+ if (unlikely(err))
+ goto out_args;
+
+ bstart = au_dbstart(dentry);
+ bwh = au_dbwh(dentry);
+ bindex = -1;
+ wh_dentry = lock_hdir_create_wh(dentry, /*isdir*/1, &bindex, &dt);
+ //wh_dentry = ERR_PTR(-1);
+ err = PTR_ERR(wh_dentry);
+ if (IS_ERR(wh_dentry))
+ goto out_args;
+
+ AuDebugOn(au_dbstart(dentry) != bstart);
+ h_dentry = au_h_dptr(dentry, bstart);
+ dget(h_dentry);
+
+ rmdir_later = 0;
+ if (bindex == bstart) {
+ h_dir = h_dentry->d_parent->d_inode; /* dir inode is locked */
+ IMustLock(h_dir);
+ err = renwh_and_rmdir(dentry, bstart, whlist, dir);
+ //err = -1;
+ if (err > 0) {
+ rmdir_later = err;
+ err = 0;
+ }
+ } else {
+ /* dir inode is locked */
+ AuDebugOn(!wh_dentry
+ || wh_dentry->d_parent != au_h_dptr(parent, bindex));
+ h_dir = wh_dentry->d_parent->d_inode;
+ IMustLock(h_dir);
+ err = 0;
+ }
+
+ sb = dentry->d_sb;
+ mnt_flags = au_mntflags(sb);
+ if (!err) {
+ //aufs_bindex_t bi, bend;
+
+ if (unlikely(au_opt_test(mnt_flags, UDBA_INOTIFY)
+ && rmdir_later))
+ au_reset_hinotify(inode, /*flags*/0);
+ clear_nlink(inode);
+ au_set_dbdiropq(dentry, -1);
+ epilog(dir, dentry, bindex);
+
+ if (rmdir_later) {
+ au_whtmp_kick_rmdir(h_dentry, whlist, bstart, dir,
+ inode, /*noself*/1, args);
+ args = NULL;
+ }
+
+ goto out_unlock; /* success */
+ }
+
+ /* revert */
+ LKTRLabel(revert);
+ if (wh_dentry) {
+ int rerr;
+ unsigned int rev_flags;
+
+ rev_flags = 0;
+ if (unlikely(au_opt_test_dlgt(mnt_flags)))
+ au_fset_rev(rev_flags, DLGT);
+ rerr = do_revert(err, wh_dentry, dentry, bwh, &dt, rev_flags);
+ if (rerr)
+ err = rerr;
+ }
+
+ out_unlock:
+ au_hdir_unlock(h_dir, dir, bindex);
+ dput(wh_dentry);
+ dput(h_dentry);
+ out_args:
+ di_write_unlock(parent);
+ aufs_read_unlock(dentry, AuLock_DW);
+ kfree(args);
+ out_whlist:
+ au_nhash_del(whlist);
+ out:
+ AuTraceErr(err);
+ return err;
+}
--
1.4.4.4
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