Linux-libre 4.2.1-gnupck-4.2.1-gnu

1 files changed, 550 insertions, 0 deletions

diff --git a/fs/aufs/dinfo.c b/fs/aufs/dinfo.c
new file mode 100644
index 000000000..7b9ca3b88
--- /dev/null
+++ b/fs/aufs/dinfo.c
@@ -0,0 +1,550 @@
+/*
+ * Copyright (C) 2005-2015 Junjiro R. 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, see <http://www.gnu.org/licenses/>.
+ */
+
+/*
+ * dentry private data
+ */
+
+#include "aufs.h"
+
+void au_di_init_once(void *_dinfo)
+{
+	struct au_dinfo *dinfo = _dinfo;
+	static struct lock_class_key aufs_di;
+
+	au_rw_init(&dinfo->di_rwsem);
+	au_rw_class(&dinfo->di_rwsem, &aufs_di);
+}
+
+struct au_dinfo *au_di_alloc(struct super_block *sb, unsigned int lsc)
+{
+	struct au_dinfo *dinfo;
+	int nbr, i;
+
+	dinfo = au_cache_alloc_dinfo();
+	if (unlikely(!dinfo))
+		goto out;
+
+	nbr = au_sbend(sb) + 1;
+	if (nbr <= 0)
+		nbr = 1;
+	dinfo->di_hdentry = kcalloc(nbr, sizeof(*dinfo->di_hdentry), GFP_NOFS);
+	if (dinfo->di_hdentry) {
+		au_rw_write_lock_nested(&dinfo->di_rwsem, lsc);
+		dinfo->di_bstart = -1;
+		dinfo->di_bend = -1;
+		dinfo->di_bwh = -1;
+		dinfo->di_bdiropq = -1;
+		dinfo->di_tmpfile = 0;
+		for (i = 0; i < nbr; i++)
+			dinfo->di_hdentry[i].hd_id = -1;
+		goto out;
+	}
+
+	au_cache_free_dinfo(dinfo);
+	dinfo = NULL;
+
+out:
+	return dinfo;
+}
+
+void au_di_free(struct au_dinfo *dinfo)
+{
+	struct au_hdentry *p;
+	aufs_bindex_t bend, bindex;
+
+	/* dentry may not be revalidated */
+	bindex = dinfo->di_bstart;
+	if (bindex >= 0) {
+		bend = dinfo->di_bend;
+		p = dinfo->di_hdentry + bindex;
+		while (bindex++ <= bend)
+			au_hdput(p++);
+	}
+	kfree(dinfo->di_hdentry);
+	au_cache_free_dinfo(dinfo);
+}
+
+void au_di_swap(struct au_dinfo *a, struct au_dinfo *b)
+{
+	struct au_hdentry *p;
+	aufs_bindex_t bi;
+
+	AuRwMustWriteLock(&a->di_rwsem);
+	AuRwMustWriteLock(&b->di_rwsem);
+
+#define DiSwap(v, name)				\
+	do {					\
+		v = a->di_##name;		\
+		a->di_##name = b->di_##name;	\
+		b->di_##name = v;		\
+	} while (0)
+
+	DiSwap(p, hdentry);
+	DiSwap(bi, bstart);
+	DiSwap(bi, bend);
+	DiSwap(bi, bwh);
+	DiSwap(bi, bdiropq);
+	/* smp_mb(); */
+
+#undef DiSwap
+}
+
+void au_di_cp(struct au_dinfo *dst, struct au_dinfo *src)
+{
+	AuRwMustWriteLock(&dst->di_rwsem);
+	AuRwMustWriteLock(&src->di_rwsem);
+
+	dst->di_bstart = src->di_bstart;
+	dst->di_bend = src->di_bend;
+	dst->di_bwh = src->di_bwh;
+	dst->di_bdiropq = src->di_bdiropq;
+	/* smp_mb(); */
+}
+
+int au_di_init(struct dentry *dentry)
+{
+	int err;
+	struct super_block *sb;
+	struct au_dinfo *dinfo;
+
+	err = 0;
+	sb = dentry->d_sb;
+	dinfo = au_di_alloc(sb, AuLsc_DI_CHILD);
+	if (dinfo) {
+		atomic_set(&dinfo->di_generation, au_sigen(sb));
+		/* smp_mb(); */ /* atomic_set */
+		dentry->d_fsdata = dinfo;
+	} else
+		err = -ENOMEM;
+
+	return err;
+}
+
+void au_di_fin(struct dentry *dentry)
+{
+	struct au_dinfo *dinfo;
+
+	dinfo = au_di(dentry);
+	AuRwDestroy(&dinfo->di_rwsem);
+	au_di_free(dinfo);
+}
+
+int au_di_realloc(struct au_dinfo *dinfo, int nbr)
+{
+	int err, sz;
+	struct au_hdentry *hdp;
+
+	AuRwMustWriteLock(&dinfo->di_rwsem);
+
+	err = -ENOMEM;
+	sz = sizeof(*hdp) * (dinfo->di_bend + 1);
+	if (!sz)
+		sz = sizeof(*hdp);
+	hdp = au_kzrealloc(dinfo->di_hdentry, sz, sizeof(*hdp) * nbr, GFP_NOFS);
+	if (hdp) {
+		dinfo->di_hdentry = hdp;
+		err = 0;
+	}
+
+	return err;
+}
+
+/* ---------------------------------------------------------------------- */
+
+static void do_ii_write_lock(struct inode *inode, unsigned int lsc)
+{
+	switch (lsc) {
+	case AuLsc_DI_CHILD:
+		ii_write_lock_child(inode);
+		break;
+	case AuLsc_DI_CHILD2:
+		ii_write_lock_child2(inode);
+		break;
+	case AuLsc_DI_CHILD3:
+		ii_write_lock_child3(inode);
+		break;
+	case AuLsc_DI_PARENT:
+		ii_write_lock_parent(inode);
+		break;
+	case AuLsc_DI_PARENT2:
+		ii_write_lock_parent2(inode);
+		break;
+	case AuLsc_DI_PARENT3:
+		ii_write_lock_parent3(inode);
+		break;
+	default:
+		BUG();
+	}
+}
+
+static void do_ii_read_lock(struct inode *inode, unsigned int lsc)
+{
+	switch (lsc) {
+	case AuLsc_DI_CHILD:
+		ii_read_lock_child(inode);
+		break;
+	case AuLsc_DI_CHILD2:
+		ii_read_lock_child2(inode);
+		break;
+	case AuLsc_DI_CHILD3:
+		ii_read_lock_child3(inode);
+		break;
+	case AuLsc_DI_PARENT:
+		ii_read_lock_parent(inode);
+		break;
+	case AuLsc_DI_PARENT2:
+		ii_read_lock_parent2(inode);
+		break;
+	case AuLsc_DI_PARENT3:
+		ii_read_lock_parent3(inode);
+		break;
+	default:
+		BUG();
+	}
+}
+
+void di_read_lock(struct dentry *d, int flags, unsigned int lsc)
+{
+	struct inode *inode;
+
+	au_rw_read_lock_nested(&au_di(d)->di_rwsem, lsc);
+	if (d_really_is_positive(d)) {
+		inode = d_inode(d);
+		if (au_ftest_lock(flags, IW))
+			do_ii_write_lock(inode, lsc);
+		else if (au_ftest_lock(flags, IR))
+			do_ii_read_lock(inode, lsc);
+	}
+}
+
+void di_read_unlock(struct dentry *d, int flags)
+{
+	struct inode *inode;
+
+	if (d_really_is_positive(d)) {
+		inode = d_inode(d);
+		if (au_ftest_lock(flags, IW)) {
+			au_dbg_verify_dinode(d);
+			ii_write_unlock(inode);
+		} else if (au_ftest_lock(flags, IR)) {
+			au_dbg_verify_dinode(d);
+			ii_read_unlock(inode);
+		}
+	}
+	au_rw_read_unlock(&au_di(d)->di_rwsem);
+}
+
+void di_downgrade_lock(struct dentry *d, int flags)
+{
+	if (d_really_is_positive(d) && au_ftest_lock(flags, IR))
+		ii_downgrade_lock(d_inode(d));
+	au_rw_dgrade_lock(&au_di(d)->di_rwsem);
+}
+
+void di_write_lock(struct dentry *d, unsigned int lsc)
+{
+	au_rw_write_lock_nested(&au_di(d)->di_rwsem, lsc);
+	if (d_really_is_positive(d))
+		do_ii_write_lock(d_inode(d), lsc);
+}
+
+void di_write_unlock(struct dentry *d)
+{
+	au_dbg_verify_dinode(d);
+	if (d_really_is_positive(d))
+		ii_write_unlock(d_inode(d));
+	au_rw_write_unlock(&au_di(d)->di_rwsem);
+}
+
+void di_write_lock2_child(struct dentry *d1, struct dentry *d2, int isdir)
+{
+	AuDebugOn(d1 == d2
+		  || d_inode(d1) == d_inode(d2)
+		  || d1->d_sb != d2->d_sb);
+
+	if (isdir && au_test_subdir(d1, d2)) {
+		di_write_lock_child(d1);
+		di_write_lock_child2(d2);
+	} else {
+		/* there should be no races */
+		di_write_lock_child(d2);
+		di_write_lock_child2(d1);
+	}
+}
+
+void di_write_lock2_parent(struct dentry *d1, struct dentry *d2, int isdir)
+{
+	AuDebugOn(d1 == d2
+		  || d_inode(d1) == d_inode(d2)
+		  || d1->d_sb != d2->d_sb);
+
+	if (isdir && au_test_subdir(d1, d2)) {
+		di_write_lock_parent(d1);
+		di_write_lock_parent2(d2);
+	} else {
+		/* there should be no races */
+		di_write_lock_parent(d2);
+		di_write_lock_parent2(d1);
+	}
+}
+
+void di_write_unlock2(struct dentry *d1, struct dentry *d2)
+{
+	di_write_unlock(d1);
+	if (d_inode(d1) == d_inode(d2))
+		au_rw_write_unlock(&au_di(d2)->di_rwsem);
+	else
+		di_write_unlock(d2);
+}
+
+/* ---------------------------------------------------------------------- */
+
+struct dentry *au_h_dptr(struct dentry *dentry, aufs_bindex_t bindex)
+{
+	struct dentry *d;
+
+	DiMustAnyLock(dentry);
+
+	if (au_dbstart(dentry) < 0 || bindex < au_dbstart(dentry))
+		return NULL;
+	AuDebugOn(bindex < 0);
+	d = au_di(dentry)->di_hdentry[0 + bindex].hd_dentry;
+	AuDebugOn(d && au_dcount(d) <= 0);
+	return d;
+}
+
+/*
+ * extended version of au_h_dptr().
+ * returns a hashed and positive (or linkable) h_dentry in bindex, NULL, or
+ * error.
+ */
+struct dentry *au_h_d_alias(struct dentry *dentry, aufs_bindex_t bindex)
+{
+	struct dentry *h_dentry;
+	struct inode *inode, *h_inode;
+
+	AuDebugOn(d_really_is_negative(dentry));
+
+	h_dentry = NULL;
+	if (au_dbstart(dentry) <= bindex
+	    && bindex <= au_dbend(dentry))
+		h_dentry = au_h_dptr(dentry, bindex);
+	if (h_dentry && !au_d_linkable(h_dentry)) {
+		dget(h_dentry);
+		goto out; /* success */
+	}
+
+	inode = d_inode(dentry);
+	AuDebugOn(bindex < au_ibstart(inode));
+	AuDebugOn(au_ibend(inode) < bindex);
+	h_inode = au_h_iptr(inode, bindex);
+	h_dentry = d_find_alias(h_inode);
+	if (h_dentry) {
+		if (!IS_ERR(h_dentry)) {
+			if (!au_d_linkable(h_dentry))
+				goto out; /* success */
+			dput(h_dentry);
+		} else
+			goto out;
+	}
+
+	if (au_opt_test(au_mntflags(dentry->d_sb), PLINK)) {
+		h_dentry = au_plink_lkup(inode, bindex);
+		AuDebugOn(!h_dentry);
+		if (!IS_ERR(h_dentry)) {
+			if (!au_d_hashed_positive(h_dentry))
+				goto out; /* success */
+			dput(h_dentry);
+			h_dentry = NULL;
+		}
+	}
+
+out:
+	AuDbgDentry(h_dentry);
+	return h_dentry;
+}
+
+aufs_bindex_t au_dbtail(struct dentry *dentry)
+{
+	aufs_bindex_t bend, bwh;
+
+	bend = au_dbend(dentry);
+	if (0 <= bend) {
+		bwh = au_dbwh(dentry);
+		if (!bwh)
+			return bwh;
+		if (0 < bwh && bwh < bend)
+			return bwh - 1;
+	}
+	return bend;
+}
+
+aufs_bindex_t au_dbtaildir(struct dentry *dentry)
+{
+	aufs_bindex_t bend, bopq;
+
+	bend = au_dbtail(dentry);
+	if (0 <= bend) {
+		bopq = au_dbdiropq(dentry);
+		if (0 <= bopq && bopq < bend)
+			bend = bopq;
+	}
+	return bend;
+}
+
+/* ---------------------------------------------------------------------- */
+
+void au_set_h_dptr(struct dentry *dentry, aufs_bindex_t bindex,
+		   struct dentry *h_dentry)
+{
+	struct au_hdentry *hd = au_di(dentry)->di_hdentry + bindex;
+	struct au_branch *br;
+
+	DiMustWriteLock(dentry);
+
+	au_hdput(hd);
+	hd->hd_dentry = h_dentry;
+	if (h_dentry) {
+		br = au_sbr(dentry->d_sb, bindex);
+		hd->hd_id = br->br_id;
+	}
+}
+
+int au_dbrange_test(struct dentry *dentry)
+{
+	int err;
+	aufs_bindex_t bstart, bend;
+
+	err = 0;
+	bstart = au_dbstart(dentry);
+	bend = au_dbend(dentry);
+	if (bstart >= 0)
+		AuDebugOn(bend < 0 && bstart > bend);
+	else {
+		err = -EIO;
+		AuDebugOn(bend >= 0);
+	}
+
+	return err;
+}
+
+int au_digen_test(struct dentry *dentry, unsigned int sigen)
+{
+	int err;
+
+	err = 0;
+	if (unlikely(au_digen(dentry) != sigen
+		     || au_iigen_test(d_inode(dentry), sigen)))
+		err = -EIO;
+
+	return err;
+}
+
+void au_update_digen(struct dentry *dentry)
+{
+	atomic_set(&au_di(dentry)->di_generation, au_sigen(dentry->d_sb));
+	/* smp_mb(); */ /* atomic_set */
+}
+
+void au_update_dbrange(struct dentry *dentry, int do_put_zero)
+{
+	struct au_dinfo *dinfo;
+	struct dentry *h_d;
+	struct au_hdentry *hdp;
+
+	DiMustWriteLock(dentry);
+
+	dinfo = au_di(dentry);
+	if (!dinfo || dinfo->di_bstart < 0)
+		return;
+
+	hdp = dinfo->di_hdentry;
+	if (do_put_zero) {
+		aufs_bindex_t bindex, bend;
+
+		bend = dinfo->di_bend;
+		for (bindex = dinfo->di_bstart; bindex <= bend; bindex++) {
+			h_d = hdp[0 + bindex].hd_dentry;
+			if (h_d && d_is_negative(h_d))
+				au_set_h_dptr(dentry, bindex, NULL);
+		}
+	}
+
+	dinfo->di_bstart = -1;
+	while (++dinfo->di_bstart <= dinfo->di_bend)
+		if (hdp[0 + dinfo->di_bstart].hd_dentry)
+			break;
+	if (dinfo->di_bstart > dinfo->di_bend) {
+		dinfo->di_bstart = -1;
+		dinfo->di_bend = -1;
+		return;
+	}
+
+	dinfo->di_bend++;
+	while (0 <= --dinfo->di_bend)
+		if (hdp[0 + dinfo->di_bend].hd_dentry)
+			break;
+	AuDebugOn(dinfo->di_bstart > dinfo->di_bend || dinfo->di_bend < 0);
+}
+
+void au_update_dbstart(struct dentry *dentry)
+{
+	aufs_bindex_t bindex, bend;
+	struct dentry *h_dentry;
+
+	bend = au_dbend(dentry);
+	for (bindex = au_dbstart(dentry); bindex <= bend; bindex++) {
+		h_dentry = au_h_dptr(dentry, bindex);
+		if (!h_dentry)
+			continue;
+		if (d_is_positive(h_dentry)) {
+			au_set_dbstart(dentry, bindex);
+			return;
+		}
+		au_set_h_dptr(dentry, bindex, NULL);
+	}
+}
+
+void au_update_dbend(struct dentry *dentry)
+{
+	aufs_bindex_t bindex, bstart;
+	struct dentry *h_dentry;
+
+	bstart = au_dbstart(dentry);
+	for (bindex = au_dbend(dentry); bindex >= bstart; bindex--) {
+		h_dentry = au_h_dptr(dentry, bindex);
+		if (!h_dentry)
+			continue;
+		if (d_is_positive(h_dentry)) {
+			au_set_dbend(dentry, bindex);
+			return;
+		}
+		au_set_h_dptr(dentry, bindex, NULL);
+	}
+}
+
+int au_find_dbindex(struct dentry *dentry, struct dentry *h_dentry)
+{
+	aufs_bindex_t bindex, bend;
+
+	bend = au_dbend(dentry);
+	for (bindex = au_dbstart(dentry); bindex <= bend; bindex++)
+		if (au_h_dptr(dentry, bindex) == h_dentry)
+			return bindex;
+	return -1;
+}