From: Junjiro Okajima <hooanon05@xxxxxxxxxxx>
initial commit
main readdir function
Signed-off-by: Junjiro Okajima <hooanon05@xxxxxxxxxxx>
---
fs/aufs/vdir.c | 928 ++++++++++++++++++++++++++++++++++++++++++++++++++++++++
1 files changed, 928 insertions(+), 0 deletions(-)
create mode 100644 fs/aufs/vdir.c
diff --git a/fs/aufs/vdir.c b/fs/aufs/vdir.c
new file mode 100644
index 0000000..6371160
--- /dev/null
+++ b/fs/aufs/vdir.c
@@ -0,0 +1,928 @@
+/*
+ * 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
+ */
+
+/*
+ * virtual or vertical directory
+ */
+
+#include "aufs.h"
+
+static int calc_size(int namelen)
+{
+ int sz;
+
+ sz = sizeof(struct au_vdir_de) + namelen;
+ if (sizeof(ino_t) == sizeof(long)) {
+ const int mask = sizeof(ino_t) - 1;
+ if (sz & mask) {
+ sz += sizeof(ino_t);
+ sz &= ~mask;
+ }
+ }
+
+ AuDebugOn(sz % sizeof(ino_t));
+ return sz;
+}
+
+static int set_deblk_end(union au_vdir_deblk_p *p,
+ union au_vdir_deblk_p *deblk_end)
+{
+ if (calc_size(0) <= deblk_end->p - p->p) {
+ p->de->de_str.len = 0;
+ /* smp_mb(); */
+ return 0;
+ }
+ return -1; /* error */
+}
+
+/* returns true or false */
+static int is_deblk_end(union au_vdir_deblk_p *p,
+ union au_vdir_deblk_p *deblk_end)
+{
+ if (calc_size(0) <= deblk_end->p - p->p)
+ return !p->de->de_str.len;
+ return 1;
+}
+
+static au_vdir_deblk_t *last_deblk(struct au_vdir *vdir)
+{
+ return vdir->vd_deblk[vdir->vd_nblk - 1];
+}
+
+void au_nhash_init(struct au_nhash *nhash)
+{
+ int i;
+ for (i = 0; i < AuSize_NHASH; i++)
+ INIT_HLIST_HEAD(nhash->heads + i);
+}
+
+struct au_nhash *au_nhash_new(gfp_t gfp)
+{
+ struct au_nhash *nhash;
+
+ nhash = kmalloc(sizeof(*nhash), gfp);
+ if (nhash) {
+ au_nhash_init(nhash);
+ return nhash;
+ }
+ return ERR_PTR(-ENOMEM);
+}
+
+void au_nhash_del(struct au_nhash *nhash)
+{
+ au_nhash_fin(nhash);
+ kfree(nhash);
+}
+
+void au_nhash_move(struct au_nhash *dst, struct au_nhash *src)
+{
+ int i;
+
+ AuTraceEnter();
+
+ *dst = *src;
+ for (i = 0; i < AuSize_NHASH; i++) {
+ struct hlist_head *h;
+ h = dst->heads + i;
+ if (h->first)
+ h->first->pprev = &h->first;
+ INIT_HLIST_HEAD(src->heads + i);
+ }
+ /* smp_mb(); */
+}
+
+/* ---------------------------------------------------------------------- */
+
+void au_nhash_fin(struct au_nhash *whlist)
+{
+ int i;
+ struct hlist_head *head;
+ struct au_vdir_wh *tpos;
+ struct hlist_node *pos, *n;
+
+ AuTraceEnter();
+
+ for (i = 0; i < AuSize_NHASH; i++) {
+ head = whlist->heads + i;
+ hlist_for_each_entry_safe(tpos, pos, n, head, wh_hash) {
+ /* hlist_del(pos); */
+ kfree(tpos);
+ }
+ }
+}
+
+int au_nhash_test_longer_wh(struct au_nhash *whlist, aufs_bindex_t btgt,
+ int limit)
+{
+ int n, i;
+ struct hlist_head *head;
+ struct au_vdir_wh *tpos;
+ struct hlist_node *pos;
+
+ LKTRTrace("limit %d\n", limit);
+
+ n = 0;
+ for (i = 0; i < AuSize_NHASH; i++) {
+ head = whlist->heads + i;
+ hlist_for_each_entry(tpos, pos, head, wh_hash)
+ if (tpos->wh_bindex == btgt && ++n > limit)
+ return 1;
+ }
+ return 0;
+}
+
+static unsigned int au_name_hash(const unsigned char *name, unsigned int len)
+{
+ return (full_name_hash(name, len) % AuSize_NHASH);
+}
+
+/* returns found(true) or not */
+int au_nhash_test_known_wh(struct au_nhash *whlist, char *name, int namelen)
+{
+ struct hlist_head *head;
+ struct au_vdir_wh *tpos;
+ struct hlist_node *pos;
+ struct au_vdir_destr *str;
+
+ LKTRTrace("%.*s\n", namelen, name);
+
+ head = whlist->heads + au_name_hash(name, namelen);
+ hlist_for_each_entry(tpos, pos, head, wh_hash) {
+ str = &tpos->wh_str;
+ LKTRTrace("%.*s\n", str->len, str->name);
+ if (str->len == namelen && !memcmp(str->name, name, namelen))
+ return 1;
+ }
+ return 0;
+}
+
+int au_nhash_append_wh(struct au_nhash *whlist, char *name, int namelen,
+ ino_t ino, unsigned int d_type, aufs_bindex_t bindex,
+ unsigned char shwh)
+{
+ int err;
+ struct au_vdir_destr *str;
+ struct au_vdir_wh *wh;
+
+ LKTRTrace("%.*s\n", namelen, name);
+
+ err = -ENOMEM;
+ wh = kmalloc(sizeof(*wh) + namelen, GFP_TEMPORARY);
+ if (unlikely(!wh))
+ goto out;
+ err = 0;
+ wh->wh_bindex = bindex;
+ if (unlikely(shwh))
+ au_shwh_init_wh(wh, ino, d_type);
+ str = &wh->wh_str;
+ str->len = namelen;
+ memcpy(str->name, name, namelen);
+ hlist_add_head(&wh->wh_hash,
+ whlist->heads + au_name_hash(name, namelen));
+ /* smp_mb(); */
+
+ out:
+ AuTraceErr(err);
+ return err;
+}
+
+/* ---------------------------------------------------------------------- */
+
+void au_vdir_free(struct au_vdir *vdir)
+{
+ au_vdir_deblk_t **deblk;
+
+ AuTraceEnter();
+
+ deblk = vdir->vd_deblk;
+ while (vdir->vd_nblk--) {
+ kfree(*deblk);
+ deblk++;
+ }
+ kfree(vdir->vd_deblk);
+ au_cache_free_vdir(vdir);
+}
+
+static int append_deblk(struct au_vdir *vdir)
+{
+ int err, sz, i;
+ au_vdir_deblk_t **o;
+ union au_vdir_deblk_p p, deblk_end;
+
+ AuTraceEnter();
+
+ err = -ENOMEM;
+ sz = sizeof(*o) * vdir->vd_nblk;
+ o = au_kzrealloc(vdir->vd_deblk, sz, sz + sizeof(*o), GFP_KERNEL);
+ if (unlikely(!o))
+ goto out;
+ vdir->vd_deblk = o;
+ p.deblk = kmalloc(sizeof(*p.deblk), GFP_KERNEL);
+ if (p.deblk) {
+ i = vdir->vd_nblk++;
+ vdir->vd_deblk[i] = p.deblk;
+ vdir->vd_last.i = i;
+ vdir->vd_last.p.p = p.p;
+ deblk_end.deblk = p.deblk + 1;
+ err = set_deblk_end(&p, &deblk_end);
+ AuDebugOn(err);
+ }
+
+ out:
+ AuTraceErr(err);
+ return err;
+}
+
+static struct au_vdir *alloc_vdir(void)
+{
+ struct au_vdir *vdir;
+ int err;
+
+ AuTraceEnter();
+
+ err = -ENOMEM;
+ vdir = au_cache_alloc_vdir();
+ if (unlikely(!vdir))
+ goto out;
+ vdir->vd_deblk = kzalloc(sizeof(*vdir->vd_deblk), GFP_KERNEL);
+ if (unlikely(!vdir->vd_deblk))
+ goto out_free;
+
+ vdir->vd_nblk = 0;
+ vdir->vd_version = 0;
+ vdir->vd_jiffy = 0;
+ err = append_deblk(vdir);
+ if (!err)
+ return vdir; /* success */
+
+ kfree(vdir->vd_deblk);
+
+ out_free:
+ au_cache_free_vdir(vdir);
+ out:
+ vdir = ERR_PTR(err);
+ AuTraceErrPtr(vdir);
+ return vdir;
+}
+
+static int reinit_vdir(struct au_vdir *vdir)
+{
+ int err;
+ union au_vdir_deblk_p p, deblk_end;
+
+ AuTraceEnter();
+
+ while (vdir->vd_nblk > 1) {
+ kfree(vdir->vd_deblk[vdir->vd_nblk - 1]);
+ vdir->vd_deblk[vdir->vd_nblk - 1] = NULL;
+ vdir->vd_nblk--;
+ }
+ p.deblk = vdir->vd_deblk[0];
+ deblk_end.deblk = p.deblk + 1;
+ err = set_deblk_end(&p, &deblk_end);
+ AuDebugOn(err);
+ vdir->vd_version = 0;
+ vdir->vd_jiffy = 0;
+ vdir->vd_last.i = 0;
+ vdir->vd_last.p.deblk = vdir->vd_deblk[0];
+ /* smp_mb(); */
+ return err;
+}
+
+/* ---------------------------------------------------------------------- */
+
+static void free_dehlist(struct au_nhash *dehlist)
+{
+ int i;
+ struct hlist_head *head;
+ struct au_vdir_dehstr *tpos;
+ struct hlist_node *pos, *n;
+
+ AuTraceEnter();
+
+ for (i = 0; i < AuSize_NHASH; i++) {
+ head = dehlist->heads + i;
+ hlist_for_each_entry_safe(tpos, pos, n, head, hash) {
+ /* hlist_del(pos); */
+ au_cache_free_dehstr(tpos);
+ }
+ }
+}
+
+/* returns found(true) or not */
+static int test_known(struct au_nhash *delist, char *name, int namelen)
+{
+ struct hlist_head *head;
+ struct au_vdir_dehstr *tpos;
+ struct hlist_node *pos;
+ struct au_vdir_destr *str;
+
+ LKTRTrace("%.*s\n", namelen, name);
+
+ head = delist->heads + au_name_hash(name, namelen);
+ hlist_for_each_entry(tpos, pos, head, hash) {
+ str = tpos->str;
+ LKTRTrace("%.*s\n", str->len, str->name);
+ if (str->len == namelen && !memcmp(str->name, name, namelen))
+ return 1;
+ }
+ return 0;
+
+}
+
+static int append_de(struct au_vdir *vdir, char *name, int namelen, ino_t ino,
+ unsigned int d_type, struct au_nhash *delist)
+{
+ int err, sz;
+ union au_vdir_deblk_p p, *room, deblk_end;
+ struct au_vdir_dehstr *dehstr;
+
+ LKTRTrace("%.*s %d, i%lu, dt%u\n", namelen, name, namelen, ino, d_type);
+
+ p.deblk = last_deblk(vdir);
+ deblk_end.deblk = p.deblk + 1;
+ room = &vdir->vd_last.p;
+ AuDebugOn(room->p < p.p || deblk_end.p <= room->p
+ || !is_deblk_end(room, &deblk_end));
+
+ sz = calc_size(namelen);
+ if (unlikely(sz > deblk_end.p - room->p)) {
+ err = append_deblk(vdir);
+ if (unlikely(err))
+ goto out;
+ p.deblk = last_deblk(vdir);
+ deblk_end.deblk = p.deblk + 1;
+ /* smp_mb(); */
+ AuDebugOn(room->p != p.p);
+ }
+
+ err = -ENOMEM;
+ dehstr = au_cache_alloc_dehstr();
+ if (unlikely(!dehstr))
+ goto out;
+ dehstr->str = &room->de->de_str;
+ hlist_add_head(&dehstr->hash,
+ delist->heads + au_name_hash(name, namelen));
+
+ room->de->de_ino = ino;
+ room->de->de_type = d_type;
+ room->de->de_str.len = namelen;
+ memcpy(room->de->de_str.name, name, namelen);
+
+ err = 0;
+ room->p += sz;
+ if (unlikely(set_deblk_end(room, &deblk_end)))
+ err = append_deblk(vdir);
+ /* smp_mb(); */
+
+ out:
+ AuTraceErr(err);
+ return err;
+}
+
+/* ---------------------------------------------------------------------- */
+
+static int au_ino(struct super_block *sb, aufs_bindex_t bindex, ino_t h_ino,
+ ino_t *ino)
+{
+ int err;
+ struct au_xino_entry xinoe;
+ static DEFINE_MUTEX(mtx);
+
+ /* a race condition for hardlinks */
+ mutex_lock(&mtx);
+ err = au_xino_read(sb, bindex, h_ino, &xinoe);
+ if (unlikely(err))
+ goto out;
+
+ if (!xinoe.ino) {
+ err = -EIO;
+ xinoe.ino = au_xino_new_ino(sb);
+ if (unlikely(!xinoe.ino))
+ goto out;
+#if 0 /* reserved for future use */
+ struct inode *h_inode;
+ xinoe.h_gen = AuXino_INVALID_HGEN;
+ h_inode = ilookup(au_sbr_sb(sb, bindex), h_ino);
+ if (h_inode) {
+ if (!is_bad_inode(h_inode)) {
+ xinoe.h_gen = h_inode->i_generation;
+ WARN_ON(xinoe.h_gen == AuXino_INVALID_HGEN);
+ }
+ iput(h_inode);
+ }
+#endif
+ err = au_xino_write(sb, bindex, h_ino, &xinoe);
+ if (unlikely(err))
+ goto out;
+ }
+
+ *ino = xinoe.ino;
+
+ out:
+ mutex_unlock(&mtx);
+ AuTraceErr(err);
+ return err;
+}
+
+static int au_wh_ino(struct super_block *sb, aufs_bindex_t bindex, ino_t h_ino,
+ ino_t *ino)
+{
+#ifdef CONFIG_AUFS_SHWH
+ return au_ino(sb, bindex, h_ino, ino);
+#else
+ return 0;
+#endif
+}
+
+#define AuFillVdir_CALLED 1
+#define AuFillVdir_SHWH (1 << 1)
+#define au_ftest_fillvdir(flags, name) ((flags) & AuFillVdir_##name)
+#define au_fset_fillvdir(flags, name) { (flags) |= AuFillVdir_##name; }
+#define au_fclr_fillvdir(flags, name) { (flags) &= ~AuFillVdir_##name; }
+#ifndef CONFIG_AUFS_SHWH
+#undef AuFillVdir_SHWH
+#define AuFillVdir_SHWH 0
+#endif
+
+struct fillvdir_arg {
+ struct file *file;
+ struct au_vdir *vdir;
+ struct au_nhash *delist;
+ struct au_nhash *whlist;
+ aufs_bindex_t bindex;
+ unsigned int flags;
+ int err;
+};
+
+static int fillvdir(void *__arg, const char *__name, int namelen, loff_t offset,
+ u64 h_ino, unsigned int d_type)
+{
+ struct fillvdir_arg *arg = __arg;
+ char *name = (void *)__name;
+ aufs_bindex_t bindex, bend;
+ struct super_block *sb;
+ ino_t ino;
+
+ LKTRTrace("%.*s, namelen %d, i%Lu, dt%u\n",
+ namelen, name, namelen, (u64)h_ino, d_type);
+
+ sb = arg->file->f_dentry->d_sb;
+ bend = arg->bindex;
+ arg->err = 0;
+ au_fset_fillvdir(arg->flags, CALLED);
+ /* smp_mb(); */
+ if (namelen <= AUFS_WH_PFX_LEN
+ || memcmp(name, AUFS_WH_PFX, AUFS_WH_PFX_LEN)) {
+ for (bindex = 0; bindex < bend; bindex++)
+ if (test_known(arg->delist + bindex, name, namelen)
+ || au_nhash_test_known_wh(arg->whlist + bindex,
+ name, namelen))
+ goto out; /* already exists or whiteouted */
+
+ ino = 1; /* why does gcc warns? */
+ arg->err = au_ino(sb, bend, h_ino, &ino);
+ if (!arg->err)
+ arg->err = append_de(arg->vdir, name, namelen, ino,
+ d_type, arg->delist + bend);
+ } else {
+ name += AUFS_WH_PFX_LEN;
+ namelen -= AUFS_WH_PFX_LEN;
+ for (bindex = 0; bindex < bend; bindex++)
+ if (au_nhash_test_known_wh(arg->whlist + bend, name,
+ namelen))
+ goto out; /* already whiteouted */
+
+ ino = 1; /* dummy */
+ if (unlikely(au_ftest_fillvdir(arg->flags, SHWH)))
+ arg->err = au_wh_ino(sb, bend, h_ino, &ino);
+ if (!arg->err)
+ arg->err = au_nhash_append_wh
+ (arg->whlist + bend, name, namelen, ino, d_type,
+ bend, au_ftest_fillvdir(arg->flags, SHWH));
+ }
+
+ out:
+ if (!arg->err)
+ arg->vdir->vd_jiffy = jiffies;
+ /* smp_mb(); */
+ AuTraceErr(arg->err);
+ return arg->err;
+}
+
+static int au_handle_shwh(struct super_block *sb, struct au_vdir *vdir,
+ aufs_bindex_t bstart, aufs_bindex_t bend,
+ struct au_nhash *_whlist, struct au_nhash *_delist)
+{
+#ifdef CONFIG_AUFS_SHWH
+ int err, i;
+ struct hlist_head *head;
+ struct au_vdir_wh *tpos;
+ struct hlist_node *pos, *n;
+ char *p, *o;
+ struct au_nhash *whlist, *delist;
+ struct au_vdir_destr *destr;
+ aufs_bindex_t bindex;
+
+ AuTraceEnter();
+ AuDebugOn(!au_opt_test(au_mntflags(sb), SHWH));
+
+ err = -ENOMEM;
+ o = p = __getname();
+ if (unlikely(!p))
+ goto out;
+
+ err = 0;
+ memcpy(p, AUFS_WH_PFX, AUFS_WH_PFX_LEN);
+ p += AUFS_WH_PFX_LEN;
+ for (bindex = bstart; !err && bindex <= bend; bindex++) {
+ whlist = _whlist + bindex;
+ delist = _delist + bindex;
+
+ for (i = 0; i < AuSize_NHASH; i++) {
+ head = whlist->heads + i;
+ hlist_for_each_entry_safe(tpos, pos, n, head, wh_hash) {
+ destr = &tpos->wh_str;
+ memcpy(p, destr->name, destr->len);
+ err = append_de(vdir, o,
+ destr->len + AUFS_WH_PFX_LEN,
+ tpos->wh_ino, tpos->wh_type,
+ delist);
+ if (unlikely(err))
+ break;
+ }
+ }
+ }
+
+ __putname(o);
+
+ out:
+ AuTraceErr(err);
+ return err;
+#else
+ return 0;
+#endif
+}
+
+static int au_do_read_vdir(struct fillvdir_arg *arg)
+{
+ int err, dlgt, shwh;
+ aufs_bindex_t bend, bindex, bstart;
+ struct super_block *sb;
+ unsigned int mnt_flags;
+ struct file *hf;
+ loff_t offset;
+
+ AuTraceEnter();
+
+ err = -ENOMEM;
+ bend = au_fbend(arg->file);
+ arg->delist = kmalloc(sizeof(*arg->delist) * (bend + 1), GFP_TEMPORARY);
+ if (unlikely(!arg->delist))
+ goto out;
+ arg->whlist = kmalloc(sizeof(*arg->whlist) * (bend + 1), GFP_TEMPORARY);
+ if (unlikely(!arg->whlist))
+ goto out_delist;
+ err = 0;
+ for (bindex = 0; bindex <= bend; bindex++) {
+ au_nhash_init(arg->delist + bindex);
+ au_nhash_init(arg->whlist + bindex);
+ }
+
+ sb = arg->file->f_dentry->d_sb;
+ mnt_flags = au_mntflags(sb);
+ dlgt = !!au_opt_test_dlgt(mnt_flags);
+ arg->flags = 0;
+ shwh = 0;
+ if (unlikely(au_opt_test(mnt_flags, SHWH))) {
+ shwh = 1;
+ au_fset_fillvdir(arg->flags, SHWH);
+ }
+ bstart = au_fbstart(arg->file);
+ for (bindex = bstart; !err && bindex <= bend; bindex++) {
+ hf = au_h_fptr(arg->file, bindex);
+ if (!hf)
+ continue;
+
+ offset = vfsub_llseek(hf, 0, SEEK_SET);
+ err = offset;
+ if (unlikely(offset))
+ break;
+ arg->bindex = bindex;
+ do {
+ arg->err = 0;
+ au_fclr_fillvdir(arg->flags, CALLED);
+ /* smp_mb(); */
+ err = vfsub_readdir(hf, fillvdir, arg, dlgt);
+ if (err >= 0)
+ err = arg->err;
+ } while (!err && au_ftest_fillvdir(arg->flags, CALLED));
+ }
+
+ if (unlikely(!err && shwh))
+ err = au_handle_shwh(sb, arg->vdir, bstart, bend, arg->whlist,
+ arg->delist);
+
+ for (bindex = bstart; bindex <= bend; bindex++) {
+ free_dehlist(arg->delist + bindex);
+ au_nhash_fin(arg->whlist + bindex);
+ }
+ kfree(arg->whlist);
+
+ out_delist:
+ kfree(arg->delist);
+ out:
+ AuTraceErr(err);
+ return err;
+}
+
+static int read_vdir(struct file *file, int may_read)
+{
+ int err, do_read;
+ struct dentry *dentry;
+ struct inode *inode;
+ struct au_vdir *vdir, *allocated;
+ unsigned long expire;
+ struct fillvdir_arg arg;
+ struct super_block *sb;
+
+ dentry = file->f_dentry;
+ LKTRTrace("%.*s, may %d\n", AuDLNPair(dentry), may_read);
+ FiMustWriteLock(file);
+ inode = dentry->d_inode;
+ IMustLock(inode);
+ IiMustWriteLock(inode);
+ AuDebugOn(!S_ISDIR(inode->i_mode));
+
+ err = 0;
+ allocated = NULL;
+ do_read = 0;
+ sb = inode->i_sb;
+ expire = au_sbi(sb)->si_rdcache;
+ vdir = au_ivdir(inode);
+ if (!vdir) {
+ AuDebugOn(au_fvdir_cache(file));
+ do_read = 1;
+ vdir = alloc_vdir();
+ err = PTR_ERR(vdir);
+ if (IS_ERR(vdir))
+ goto out;
+ err = 0;
+ allocated = vdir;
+ } else if (may_read
+ && (inode->i_version != vdir->vd_version
+ || time_after(jiffies, vdir->vd_jiffy + expire))) {
+ LKTRTrace("iver %Lu, vdver %lu, exp %lu\n",
+ inode->i_version, vdir->vd_version,
+ vdir->vd_jiffy + expire);
+ do_read = 1;
+ err = reinit_vdir(vdir);
+ if (unlikely(err))
+ goto out;
+ }
+
+ if (!do_read)
+ return 0; /* success */
+
+ arg.file = file;
+ arg.vdir = vdir;
+ err = au_do_read_vdir(&arg);
+ if (!err) {
+ /* todo: necessary? */
+ /* file->f_pos = 0; */
+ vdir->vd_version = inode->i_version;
+ vdir->vd_last.i = 0;
+ vdir->vd_last.p.deblk = vdir->vd_deblk[0];
+ if (allocated)
+ au_set_ivdir(inode, allocated);
+ } else if (allocated)
+ au_vdir_free(allocated);
+
+ out:
+ AuTraceErr(err);
+ return err;
+}
+
+static int copy_vdir(struct au_vdir *tgt, struct au_vdir *src)
+{
+ int err, i, rerr, n;
+
+ AuTraceEnter();
+ AuDebugOn(tgt->vd_nblk != 1);
+
+ err = -ENOMEM;
+ if (tgt->vd_nblk < src->vd_nblk) {
+ au_vdir_deblk_t **p;
+ p = au_kzrealloc(tgt->vd_deblk, sizeof(*p) * tgt->vd_nblk,
+ sizeof(*p) * src->vd_nblk, GFP_KERNEL);
+ if (unlikely(!p))
+ goto out;
+ tgt->vd_deblk = p;
+ }
+
+ tgt->vd_nblk = src->vd_nblk;
+ n = src->vd_nblk;
+ memcpy(tgt->vd_deblk[0], src->vd_deblk[0], AuSize_DEBLK);
+ /* tgt->vd_last.i = 0; */
+ /* tgt->vd_last.p.deblk = tgt->vd_deblk[0]; */
+ tgt->vd_version = src->vd_version;
+ tgt->vd_jiffy = src->vd_jiffy;
+
+ for (i = 1; i < n; i++) {
+ tgt->vd_deblk[i] = kmalloc(AuSize_DEBLK, GFP_KERNEL);
+ if (tgt->vd_deblk[i])
+ memcpy(tgt->vd_deblk[i], src->vd_deblk[i],
+ AuSize_DEBLK);
+ else
+ goto out;
+ }
+ /* smp_mb(); */
+ return 0; /* success */
+
+ out:
+ rerr = reinit_vdir(tgt);
+ BUG_ON(rerr);
+ AuTraceErr(err);
+ return err;
+}
+
+int au_vdir_init(struct file *file)
+{
+ int err;
+ struct dentry *dentry;
+ struct inode *inode;
+ struct au_vdir *vdir_cache, *allocated;
+
+ dentry = file->f_dentry;
+ LKTRTrace("%.*s, pos %Ld\n", AuDLNPair(dentry), file->f_pos);
+ FiMustWriteLock(file);
+ inode = dentry->d_inode;
+ IiMustWriteLock(inode);
+ AuDebugOn(!S_ISDIR(inode->i_mode));
+
+ err = read_vdir(file, !file->f_pos);
+ if (unlikely(err))
+ goto out;
+
+ allocated = NULL;
+ vdir_cache = au_fvdir_cache(file);
+ if (!vdir_cache) {
+ vdir_cache = alloc_vdir();
+ err = PTR_ERR(vdir_cache);
+ if (IS_ERR(vdir_cache))
+ goto out;
+ allocated = vdir_cache;
+ } else if (!file->f_pos && vdir_cache->vd_version != file->f_version) {
+ err = reinit_vdir(vdir_cache);
+ if (unlikely(err))
+ goto out;
+ } else
+ return 0; /* success */
+
+ err = copy_vdir(vdir_cache, au_ivdir(inode));
+ if (!err) {
+ file->f_version = inode->i_version;
+ if (allocated)
+ au_set_fvdir_cache(file, allocated);
+ } else if (allocated)
+ au_vdir_free(allocated);
+
+ out:
+ AuTraceErr(err);
+ return err;
+}
+
+static loff_t calc_offset(struct au_vdir *vdir)
+{
+ loff_t offset;
+ union au_vdir_deblk_p p;
+
+ p.deblk = vdir->vd_deblk[vdir->vd_last.i];
+ offset = vdir->vd_last.p.p - p.p;
+ offset += sizeof(*p.deblk) * vdir->vd_last.i;
+ return offset;
+}
+
+/* returns true or false */
+static int seek_vdir(struct file *file)
+{
+ int valid, i, n;
+ struct dentry *dentry;
+ struct au_vdir *vdir_cache;
+ loff_t offset;
+ union au_vdir_deblk_p p, deblk_end;
+
+ dentry = file->f_dentry;
+ LKTRTrace("%.*s, pos %Ld\n", AuDLNPair(dentry), file->f_pos);
+ vdir_cache = au_fvdir_cache(file);
+ AuDebugOn(!vdir_cache);
+
+ valid = 1;
+ offset = calc_offset(vdir_cache);
+ LKTRTrace("offset %Ld\n", offset);
+ if (file->f_pos == offset)
+ goto out;
+
+ vdir_cache->vd_last.i = 0;
+ vdir_cache->vd_last.p.deblk = vdir_cache->vd_deblk[0];
+ if (!file->f_pos)
+ goto out;
+
+ valid = 0;
+ i = file->f_pos / AuSize_DEBLK;
+ LKTRTrace("i %d\n", i);
+ if (i >= vdir_cache->vd_nblk)
+ goto out;
+
+ n = vdir_cache->vd_nblk;
+ for (; i < n; i++) {
+ p.deblk = vdir_cache->vd_deblk[i];
+ deblk_end.deblk = p.deblk + 1;
+ offset = i;
+ offset *= AuSize_DEBLK;
+ while (!is_deblk_end(&p, &deblk_end) && offset < file->f_pos) {
+ int l;
+ l = calc_size(p.de->de_str.len);
+ offset += l;
+ p.p += l;
+ }
+ if (!is_deblk_end(&p, &deblk_end)) {
+ valid = 1;
+ vdir_cache->vd_last.i = i;
+ vdir_cache->vd_last.p = p;
+ break;
+ }
+ }
+
+ out:
+ /* smp_mb(); */
+ AuTraceErr(!valid);
+ return valid;
+}
+
+int au_vdir_fill_de(struct file *file, void *dirent, filldir_t filldir)
+{
+ int err, l;
+ struct dentry *dentry;
+ struct au_vdir *vdir_cache;
+ struct au_vdir_de *de;
+ union au_vdir_deblk_p deblk_end;
+
+ dentry = file->f_dentry;
+ LKTRTrace("%.*s, pos %Ld\n", AuDLNPair(dentry), file->f_pos);
+ vdir_cache = au_fvdir_cache(file);
+ AuDebugOn(!vdir_cache);
+
+ if (!seek_vdir(file))
+ return 0;
+
+ while (1) {
+ deblk_end.deblk
+ = vdir_cache->vd_deblk[vdir_cache->vd_last.i] + 1;
+ while (!is_deblk_end(&vdir_cache->vd_last.p, &deblk_end)) {
+ de = vdir_cache->vd_last.p.de;
+ LKTRTrace("%.*s, off%Ld, i%lu, dt%d\n",
+ de->de_str.len, de->de_str.name,
+ file->f_pos, de->de_ino, de->de_type);
+ err = filldir(dirent, de->de_str.name, de->de_str.len,
+ file->f_pos, de->de_ino, de->de_type);
+ if (unlikely(err)) {
+ AuTraceErr(err);
+ /* todo: ignore the error caused by udba? */
+ /* return err; */
+ return 0;
+ }
+
+ l = calc_size(de->de_str.len);
+ vdir_cache->vd_last.p.p += l;
+ file->f_pos += l;
+ }
+ if (vdir_cache->vd_last.i < vdir_cache->vd_nblk - 1) {
+ vdir_cache->vd_last.i++;
+ vdir_cache->vd_last.p.deblk
+ = vdir_cache->vd_deblk[vdir_cache->vd_last.i];
+ file->f_pos = sizeof(*vdir_cache->vd_last.p.deblk)
+ * vdir_cache->vd_last.i;
+ continue;
+ }
+ break;
+ }
+
+ /* smp_mb(); */
+ return 0;
+}
--
1.5.5.1.308.g1fbb5.dirty
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