From: Junjiro Okajima <hooanon05@xxxxxxxxxxx>
initial commit
external inode number translation table and bitmap
Signed-off-by: Junjiro Okajima <hooanon05@xxxxxxxxxxx>
---
fs/aufs/xino.c | 1212 ++++++++++++++++++++++++++++++++++++++++++++++++++++++++
1 files changed, 1212 insertions(+), 0 deletions(-)
create mode 100644 fs/aufs/xino.c
diff --git a/fs/aufs/xino.c b/fs/aufs/xino.c
new file mode 100644
index 0000000..eb5bdff
--- /dev/null
+++ b/fs/aufs/xino.c
@@ -0,0 +1,1212 @@
+/*
+ * 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
+ */
+
+/*
+ * external inode number translation table and bitmap
+ */
+
+#include <linux/uaccess.h>
+#include "aufs.h"
+
+/* ---------------------------------------------------------------------- */
+
+static ssize_t xino_fread(au_readf_t func, struct file *file, void *buf,
+ size_t size, loff_t *pos)
+{
+ ssize_t err;
+ mm_segment_t oldfs;
+
+ LKTRTrace("%.*s, sz %lu, *pos %Ld\n",
+ AuDLNPair(file->f_dentry), (unsigned long)size, *pos);
+
+ oldfs = get_fs();
+ set_fs(KERNEL_DS);
+ do {
+ /* todo: signal_pending? */
+ err = func(file, (char __user *)buf, size, pos);
+ } while (err == -EAGAIN || err == -EINTR);
+ set_fs(oldfs);
+
+#if 0 /* reserved for future use */
+ if (err > 0)
+ fsnotify_access(file->f_dentry);
+#endif
+
+ AuTraceErr(err);
+ return err;
+}
+
+/* ---------------------------------------------------------------------- */
+
+static ssize_t do_xino_fwrite(au_writef_t func, struct file *file, void *buf,
+ size_t size, loff_t *pos)
+{
+ ssize_t err;
+ mm_segment_t oldfs;
+
+ lockdep_off();
+ oldfs = get_fs();
+ set_fs(KERNEL_DS);
+ do {
+ /* todo: signal_pending? */
+ err = func(file, (const char __user *)buf, size, pos);
+ } while (err == -EAGAIN || err == -EINTR);
+ set_fs(oldfs);
+ lockdep_on();
+
+ if (err >= 0)
+ au_update_fuse_h_inode(file->f_vfsmnt, file->f_dentry);
+ /*ignore*/
+
+#if 0 /* reserved for future use */
+ if (err > 0)
+ fsnotify_modify(file->f_dentry);
+#endif
+
+ AuTraceErr(err);
+ return err;
+}
+
+struct do_xino_fwrite_args {
+ ssize_t *errp;
+ au_writef_t func;
+ struct file *file;
+ void *buf;
+ size_t size;
+ loff_t *pos;
+};
+
+static void call_do_xino_fwrite(void *args)
+{
+ struct do_xino_fwrite_args *a = args;
+ *a->errp = do_xino_fwrite(a->func, a->file, a->buf, a->size, a->pos);
+}
+
+static ssize_t xino_fwrite(au_writef_t func, struct file *file, void *buf,
+ size_t size, loff_t *pos)
+{
+ ssize_t err;
+
+ LKTRTrace("%.*s, sz %lu, *pos %Ld\n",
+ AuDLNPair(file->f_dentry), (unsigned long)size, *pos);
+
+ /* todo: signal block and no wkq? */
+ /*
+ * it breaks RLIMIT_FSIZE and normal user's limit,
+ * users should care about quota and real 'filesystem full.'
+ */
+ if (!au_test_wkq(current)) {
+ int wkq_err;
+ struct do_xino_fwrite_args args = {
+ .errp = &err,
+ .func = func,
+ .file = file,
+ .buf = buf,
+ .size = size,
+ .pos = pos
+ };
+ wkq_err = au_wkq_wait(call_do_xino_fwrite, &args, /*dlgt*/0);
+ if (unlikely(wkq_err))
+ err = wkq_err;
+ } else
+ err = do_xino_fwrite(func, file, buf, size, pos);
+
+ AuTraceErr(err);
+ return err;
+}
+
+/* ---------------------------------------------------------------------- */
+
+struct xino_do_trunc_args {
+ struct vfsmount *mnt;
+ struct au_branch *br;
+};
+
+static void xino_do_trunc(void *_args)
+{
+ struct xino_do_trunc_args *args = _args;
+ struct super_block *sb;
+ aufs_bindex_t bindex;
+ int err;
+ struct file *file;
+
+ err = 0;
+ sb = args->mnt->mnt_sb;
+ si_noflush_write_lock(sb);
+ bindex = au_br_index(sb, args->br->br_id);
+ AuDebugOn(bindex < 0);
+ err = au_xino_trunc(sb, bindex);
+ if (unlikely(err))
+ goto out;
+
+ file = args->br->br_xino;
+ au_update_fuse_h_inode(args->br->br_mnt, file->f_dentry); /*ignore*/
+ if (file->f_dentry->d_inode->i_blocks >= args->br->br_xino_upper)
+ args->br->br_xino_upper += AUFS_XINO_TRUNC_STEP;
+
+ out:
+ si_write_unlock(sb);
+ if (unlikely(err))
+ AuWarn("err b%d, (%d)\n", bindex, err);
+ au_nwt_dec(&au_sbi(sb)->si_nowait);
+ atomic_dec_return(&args->br->br_xino_running);
+ au_br_put(args->br);
+ mntput(args->mnt);
+ kfree(args);
+}
+
+static void xino_try_trunc(struct super_block *sb, struct au_branch *br)
+{
+ struct xino_do_trunc_args *args;
+ struct au_sbinfo *sbinfo;
+ struct file *file = br->br_xino;
+ int wkq_err;
+
+ au_update_fuse_h_inode(br->br_mnt, file->f_dentry); /*ignore*/
+ if (file->f_dentry->d_inode->i_blocks < br->br_xino_upper)
+ return;
+ if (atomic_inc_return(&br->br_xino_running) > 1)
+ goto out;
+
+ /* lock and kfree() will be called in trunc_xino() */
+ args = kmalloc(sizeof(*args), GFP_TEMPORARY);
+ if (args) {
+ args->mnt = au_mntcache_get(sb);
+ args->br = br;
+ au_br_get(br);
+ sbinfo = au_sbi(sb);
+ au_nwt_inc(&sbinfo->si_nowait);
+ wkq_err = au_wkq_nowait(xino_do_trunc, args, sb, /*dlgt*/0);
+ if (!wkq_err)
+ return; /* success */
+
+ AuErr("wkq %d\n", wkq_err);
+ au_nwt_dec(&sbinfo->si_nowait);
+ mntput(args->mnt);
+ au_br_put(br);
+ kfree(args);
+ } else
+ AuErr1("no memory\n");
+ out:
+ atomic_dec_return(&br->br_xino_running);
+}
+
+/* ---------------------------------------------------------------------- */
+
+#define Au_LOFF_MAX ((loff_t)LLONG_MAX)
+
+static int au_xino_do_write(au_writef_t write, struct file *file,
+ ino_t h_ino, struct au_xino_entry *xinoe)
+{
+ loff_t pos;
+ ssize_t sz;
+
+ AuTraceEnter();
+
+ pos = h_ino;
+ if (unlikely(Au_LOFF_MAX / sizeof(*xinoe) - 1 < pos)) {
+ AuIOErr1("too large hi%lu\n", h_ino);
+ return -EFBIG;
+ }
+ pos *= sizeof(*xinoe);
+ sz = xino_fwrite(write, file, xinoe, sizeof(*xinoe), &pos);
+ if (sz == sizeof(*xinoe))
+ return 0; /* success */
+
+ AuIOErr("write failed (%ld)\n", (long)sz);
+ return -EIO;
+}
+
+/*
+ * write @ino to the xinofile for the specified branch{@sb, @bindex}
+ * at the position of @_ino.
+ * when @ino is zero, it is written to the xinofile and means no entry.
+ */
+int au_xino_write(struct super_block *sb, aufs_bindex_t bindex, ino_t h_ino,
+ struct au_xino_entry *xinoe)
+{
+ int err;
+ struct file *file;
+ struct au_branch *br;
+ unsigned int mnt_flags;
+
+ LKTRTrace("b%d, hi%lu, i%lu\n", bindex, h_ino, xinoe->ino);
+ BUILD_BUG_ON(sizeof(long long) != sizeof(Au_LOFF_MAX)
+ || ((loff_t) - 1) > 0);
+
+ mnt_flags = au_mntflags(sb);
+ if (unlikely(!au_opt_test(mnt_flags, XINO)))
+ return 0;
+
+ br = au_sbr(sb, bindex);
+ file = br->br_xino;
+ AuDebugOn(!file);
+
+ err = au_xino_do_write(au_sbi(sb)->si_xwrite, file, h_ino, xinoe);
+ if (!err) {
+ if (unlikely(au_opt_test(mnt_flags, TRUNC_XINO)
+ && au_test_trunc_xino(br->br_mnt->mnt_sb)))
+ xino_try_trunc(sb, br);
+ return 0; /* success */
+ }
+
+ AuIOErr("write failed (%d)\n", err);
+ return -EIO;
+}
+
+/* ---------------------------------------------------------------------- */
+
+static const int page_bits = (int)PAGE_SIZE * BITS_PER_BYTE;
+static ino_t xib_calc_ino(unsigned long pindex, int bit)
+{
+ ino_t ino;
+ AuDebugOn(bit < 0 || page_bits <= bit);
+ ino = AUFS_FIRST_INO + pindex * page_bits + bit;
+ return ino;
+}
+
+static void xib_calc_bit(ino_t ino, unsigned long *pindex, int *bit)
+{
+ AuDebugOn(ino < AUFS_FIRST_INO);
+ ino -= AUFS_FIRST_INO;
+ *pindex = ino / page_bits;
+ *bit = ino % page_bits;
+}
+
+static int xib_pindex(struct super_block *sb, unsigned long pindex)
+{
+ int err;
+ struct au_sbinfo *sbinfo;
+ loff_t pos;
+ ssize_t sz;
+ struct file *xib;
+ unsigned long *p;
+
+ LKTRTrace("pindex %lu\n", pindex);
+ sbinfo = au_sbi(sb);
+ MtxMustLock(&sbinfo->si_xib_mtx);
+ AuDebugOn(pindex > ULONG_MAX / PAGE_SIZE
+ || !au_opt_test(sbinfo->si_mntflags, XINO));
+
+ if (pindex == sbinfo->si_xib_last_pindex)
+ return 0;
+
+ xib = sbinfo->si_xib;
+ p = sbinfo->si_xib_buf;
+ pos = sbinfo->si_xib_last_pindex;
+ pos *= PAGE_SIZE;
+ sz = xino_fwrite(sbinfo->si_xwrite, xib, p, PAGE_SIZE, &pos);
+ if (unlikely(sz != PAGE_SIZE))
+ goto out;
+
+ pos = pindex;
+ pos *= PAGE_SIZE;
+ if (i_size_read(xib->f_dentry->d_inode) >= pos + PAGE_SIZE)
+ sz = xino_fread(sbinfo->si_xread, xib, p, PAGE_SIZE, &pos);
+ else {
+ memset(p, 0, PAGE_SIZE);
+ sz = xino_fwrite(sbinfo->si_xwrite, xib, p, PAGE_SIZE, &pos);
+ }
+ if (sz == PAGE_SIZE) {
+ sbinfo->si_xib_last_pindex = pindex;
+ return 0; /* success */
+ }
+
+ out:
+ AuIOErr1("write failed (%ld)\n", (long)sz);
+ err = sz;
+ if (sz >= 0)
+ err = -EIO;
+ AuTraceErr(err);
+ return err;
+}
+
+/* ---------------------------------------------------------------------- */
+
+int au_xino_write0(struct super_block *sb, aufs_bindex_t bindex, ino_t h_ino,
+ ino_t ino)
+{
+ int err, bit;
+ unsigned long pindex;
+ struct au_sbinfo *sbinfo;
+ struct au_xino_entry xinoe = {
+ .ino = 0
+ };
+
+ LKTRTrace("b%d, hi%lu, i%lu\n", bindex, h_ino, ino);
+
+ sbinfo = au_sbi(sb);
+ if (unlikely(!au_opt_test(au_mntflags(sb), XINO)))
+ return 0;
+
+ err = 0;
+ if (unlikely(ino)) {
+ AuDebugOn(ino < AUFS_FIRST_INO);
+ xib_calc_bit(ino, &pindex, &bit);
+ AuDebugOn(page_bits <= bit);
+ mutex_lock(&sbinfo->si_xib_mtx);
+ err = xib_pindex(sb, pindex);
+ if (!err) {
+ clear_bit(bit, sbinfo->si_xib_buf);
+ sbinfo->si_xib_next_bit = bit;
+ }
+ mutex_unlock(&sbinfo->si_xib_mtx);
+ }
+
+ if (!err)
+ err = au_xino_write(sb, bindex, h_ino, &xinoe);
+ return err;
+}
+
+ino_t au_xino_new_ino(struct super_block *sb)
+{
+ ino_t ino;
+ struct au_sbinfo *sbinfo;
+ int free_bit, err;
+ unsigned long *p, pindex, ul, pend;
+ struct file *file;
+
+ AuTraceEnter();
+
+ sbinfo = au_sbi(sb);
+ if (unlikely(!au_opt_test(au_mntflags(sb), XINO)))
+ return iunique(sb, AUFS_FIRST_INO);
+
+ mutex_lock(&sbinfo->si_xib_mtx);
+ p = sbinfo->si_xib_buf;
+ free_bit = sbinfo->si_xib_next_bit;
+ if (free_bit < page_bits && !test_bit(free_bit, p))
+ goto out; /* success */
+ free_bit = find_first_zero_bit(p, page_bits);
+ if (free_bit < page_bits)
+ goto out; /* success */
+
+ pindex = sbinfo->si_xib_last_pindex;
+ for (ul = pindex - 1; ul < ULONG_MAX; ul--) {
+ err = xib_pindex(sb, ul);
+ if (unlikely(err))
+ goto out_err;
+ free_bit = find_first_zero_bit(p, page_bits);
+ if (free_bit < page_bits)
+ goto out; /* success */
+ }
+
+ file = sbinfo->si_xib;
+ pend = i_size_read(file->f_dentry->d_inode) / PAGE_SIZE;
+ for (ul = pindex + 1; ul <= pend; ul++) {
+ err = xib_pindex(sb, ul);
+ if (unlikely(err))
+ goto out_err;
+ free_bit = find_first_zero_bit(p, page_bits);
+ if (free_bit < page_bits)
+ goto out; /* success */
+ }
+ BUG();
+
+ out:
+ set_bit(free_bit, p);
+ sbinfo->si_xib_next_bit++;
+ pindex = sbinfo->si_xib_last_pindex;
+ mutex_unlock(&sbinfo->si_xib_mtx);
+ ino = xib_calc_ino(pindex, free_bit);
+ LKTRTrace("i%lu\n", ino);
+ return ino;
+ out_err:
+ mutex_unlock(&sbinfo->si_xib_mtx);
+ LKTRTrace("i0\n");
+ return 0;
+}
+
+/*
+ * read @ino from xinofile for the specified branch{@sb, @bindex}
+ * at the position of @h_ino.
+ * if @ino does not exist and @do_new is true, get new one.
+ */
+int au_xino_read(struct super_block *sb, aufs_bindex_t bindex, ino_t h_ino,
+ struct au_xino_entry *xinoe)
+{
+ int err;
+ struct file *file;
+ loff_t pos;
+ ssize_t sz;
+ struct au_sbinfo *sbinfo;
+
+ LKTRTrace("b%d, hi%lu\n", bindex, h_ino);
+
+ err = 0;
+ xinoe->ino = 0;
+ sbinfo = au_sbi(sb);
+ if (unlikely(!au_opt_test(au_mntflags(sb), XINO)))
+ return 0; /* no ino */
+
+ pos = h_ino;
+ if (unlikely(Au_LOFF_MAX / sizeof(*xinoe) - 1 < pos)) {
+ AuIOErr1("too large hi%lu\n", h_ino);
+ return -EFBIG;
+ }
+ pos *= sizeof(*xinoe);
+
+ file = au_sbr(sb, bindex)->br_xino;
+ AuDebugOn(!file);
+ if (i_size_read(file->f_dentry->d_inode) < pos + sizeof(*xinoe))
+ return 0; /* no ino */
+
+ sz = xino_fread(sbinfo->si_xread, file, xinoe, sizeof(*xinoe), &pos);
+ if (sz == sizeof(*xinoe))
+ return 0; /* success */
+
+ err = sz;
+ if (unlikely(sz >= 0)) {
+ err = -EIO;
+ AuIOErr("xino read error (%ld)\n", (long)sz);
+ }
+
+ AuTraceErr(err);
+ return err;
+}
+
+/* ---------------------------------------------------------------------- */
+
+struct file *au_xino_create(struct super_block *sb, char *fname, int silent,
+ struct dentry *parent)
+{
+ struct file *file;
+ int err;
+ struct dentry *h_parent;
+ struct inode *h_dir;
+ struct vfsub_args vargs;
+
+ LKTRTrace("%s\n", fname);
+
+ /* LSM may detect it */
+ file = vfsub_filp_open(fname, O_RDWR | O_CREAT | O_EXCL | O_LARGEFILE,
+ S_IRUGO | S_IWUGO);
+ if (IS_ERR(file)) {
+ if (!silent)
+ AuErr("open %s(%ld)\n", fname, PTR_ERR(file));
+ return file;
+ }
+
+ /* keep file count */
+ h_parent = dget_parent(file->f_dentry);
+ h_dir = h_parent->d_inode;
+ vfsub_args_init(&vargs, NULL, 0, 0);
+ mutex_lock_nested(&h_dir->i_mutex, AuLsc_I_PARENT);
+ err = vfsub_unlink(h_dir, file->f_dentry, &vargs);
+ mutex_unlock(&h_dir->i_mutex);
+ dput(h_parent);
+ if (unlikely(err)) {
+ if (!silent)
+ AuErr("unlink %s(%d)\n", fname, err);
+ goto out;
+ }
+
+ if (sb != file->f_dentry->d_sb)
+ return file; /* success */
+
+ if (!silent)
+ AuErr("%s must be outside\n", fname);
+ err = -EINVAL;
+
+ out:
+ fput(file);
+ file = ERR_PTR(err);
+ return file;
+}
+
+/*
+ * find another branch who is on the same filesystem of the specified
+ * branch{@btgt}. search until @bend.
+ */
+static int is_sb_shared(struct super_block *sb, aufs_bindex_t btgt,
+ aufs_bindex_t bend)
+{
+ aufs_bindex_t bindex;
+ struct super_block *tgt_sb = au_sbr_sb(sb, btgt);
+
+ for (bindex = 0; bindex <= bend; bindex++)
+ if (unlikely(btgt != bindex && tgt_sb == au_sbr_sb(sb, bindex)))
+ return bindex;
+ return -1;
+}
+
+/*
+ * create a new xinofile at the same place/path as @base_file.
+ */
+static
+struct file *au_xino_create2(struct super_block *sb, struct file *base_file,
+ struct file *copy_src)
+{
+ struct file *file;
+ int err;
+ struct dentry *base, *dentry, *parent;
+ struct inode *dir, *inode;
+ struct qstr *name;
+ struct vfsub_args vargs;
+ struct au_ndx ndx = {
+ .nfsmnt = NULL,
+ .flags = 0,
+ .nd = NULL,
+ /* .br = NULL */
+ };
+
+ base = base_file->f_dentry;
+ LKTRTrace("%.*s\n", AuDLNPair(base));
+ parent = base->d_parent; /* dir inode is locked */
+ dir = parent->d_inode;
+ IMustLock(dir);
+
+ file = ERR_PTR(-EINVAL);
+ if (unlikely(au_test_nfs(parent->d_sb)))
+ goto out;
+
+ /* do not superio, nor NFS. */
+ name = &base->d_name;
+ dentry = au_lkup_one(name->name, parent, name->len, &ndx);
+ if (IS_ERR(dentry)) {
+ file = (void *)dentry;
+ AuErr("%.*s lookup err %ld\n", AuLNPair(name), PTR_ERR(dentry));
+ goto out;
+ }
+ err = vfsub_create(dir, dentry, S_IRUGO | S_IWUGO, NULL, /*dlgt*/0);
+ if (unlikely(err)) {
+ file = ERR_PTR(err);
+ AuErr("%.*s create err %d\n", AuLNPair(name), err);
+ goto out_dput;
+ }
+ file = dentry_open(dget(dentry), mntget(base_file->f_vfsmnt),
+ O_RDWR | O_CREAT | O_EXCL | O_LARGEFILE);
+ if (IS_ERR(file)) {
+ AuErr("%.*s open err %ld\n", AuLNPair(name), PTR_ERR(file));
+ goto out_dput;
+ }
+ vfsub_args_init(&vargs, NULL, 0, 0);
+ err = vfsub_unlink(dir, dentry, &vargs);
+ if (unlikely(err)) {
+ AuErr("%.*s unlink err %d\n", AuLNPair(name), err);
+ goto out_fput;
+ }
+
+ if (copy_src) {
+ inode = copy_src->f_dentry->d_inode;
+ err = au_copy_file(file, copy_src, i_size_read(inode), sb);
+ if (unlikely(err)) {
+ AuErr("%.*s copy err %d\n", AuLNPair(name), err);
+ goto out_fput;
+ }
+ }
+ goto out_dput; /* success */
+
+ out_fput:
+ fput(file);
+ file = ERR_PTR(err);
+ out_dput:
+ dput(dentry);
+ out:
+ AuTraceErrPtr(file);
+ return file;
+}
+
+/* ---------------------------------------------------------------------- */
+
+/*
+ * initialize the xinofile for the specified branch{@sb, @bindex}
+ * at the place/path where @base_file indicates.
+ * test whether another branch is on the same filesystem or not,
+ * if @do_test is true.
+ */
+int au_xino_br(struct super_block *sb, struct au_branch *br, ino_t h_ino,
+ struct file *base_file, int do_test)
+{
+ int err, do_create;
+ struct au_branch *shared_br;
+ aufs_bindex_t bshared, bend;
+ struct inode *dir;
+ struct au_xino_entry xinoe;
+ struct dentry *parent;
+ struct file *file;
+
+ LKTRTrace("base_file %p, do_test %d\n", base_file, do_test);
+ SiMustWriteLock(sb);
+ AuDebugOn(!au_opt_test(au_mntflags(sb), XINO));
+ AuDebugOn(br->br_xino);
+
+ do_create = 1;
+ bshared = -1;
+ shared_br = NULL;
+ bend = au_sbend(sb);
+ if (do_test) {
+ aufs_bindex_t bindex;
+
+ struct super_block *tgt_sb = br->br_mnt->mnt_sb;
+ for (bindex = 0; bindex <= bend; bindex++)
+ if (unlikely(tgt_sb == au_sbr_sb(sb, bindex))) {
+ bshared = bindex;
+ break;
+ }
+ }
+ if (unlikely(bshared >= 0)) {
+ shared_br = au_sbr(sb, bshared);
+ do_create = !shared_br->br_xino;
+ }
+
+ if (do_create) {
+ parent = dget_parent(base_file->f_dentry);
+ dir = parent->d_inode;
+
+ mutex_lock_nested(&dir->i_mutex, AuLsc_I_PARENT);
+ file = au_xino_create2(sb, base_file, NULL);
+ err = PTR_ERR(file);
+ mutex_unlock(&dir->i_mutex);
+ dput(parent);
+ if (IS_ERR(file))
+ goto out;
+ br->br_xino = file;
+ } else {
+ br->br_xino = shared_br->br_xino;
+ get_file(br->br_xino);
+ }
+
+ xinoe.ino = AUFS_ROOT_INO;
+#if 0 /* reserved for future use */
+ xinoe.h_gen = h_inode->i_generation;
+ WARN_ON(xinoe.h_gen == AuXino_INVALID_HGEN);
+#endif
+ err = au_xino_do_write(au_sbi(sb)->si_xwrite, br->br_xino, h_ino,
+ &xinoe);
+ if (!err)
+ return 0; /* success */
+
+
+ out:
+ AuTraceErr(err);
+ return err;
+}
+
+/* too slow */
+static int do_xib_restore(struct super_block *sb, struct file *file, void *page)
+{
+ int err, bit;
+ struct au_sbinfo *sbinfo;
+ au_readf_t func;
+ loff_t pos, pend;
+ ssize_t sz;
+ struct au_xino_entry *xinoe;
+ unsigned long pindex;
+
+ AuTraceEnter();
+ SiMustWriteLock(sb);
+
+ err = 0;
+ sbinfo = au_sbi(sb);
+ func = sbinfo->si_xread;
+ pend = i_size_read(file->f_dentry->d_inode);
+#ifdef CONFIG_AUFS_DEBUG
+ if (unlikely(pend > (1 << 22)))
+ AuWarn("testing a large xino file %Ld\n", (long long)pend);
+#endif
+ pos = 0;
+ while (pos < pend) {
+ sz = xino_fread(func, file, page, PAGE_SIZE, &pos);
+ err = sz;
+ if (unlikely(sz <= 0))
+ goto out;
+
+ err = 0;
+ for (xinoe = page; sz > 0; xinoe++, sz -= sizeof(xinoe)) {
+ if (unlikely(xinoe->ino < AUFS_FIRST_INO))
+ continue;
+
+ xib_calc_bit(xinoe->ino, &pindex, &bit);
+ AuDebugOn(page_bits <= bit);
+ err = xib_pindex(sb, pindex);
+ if (!err)
+ set_bit(bit, sbinfo->si_xib_buf);
+ else
+ goto out;
+ }
+ }
+
+ out:
+ AuTraceErr(err);
+ return err;
+}
+
+static int xib_restore(struct super_block *sb)
+{
+ int err;
+ aufs_bindex_t bindex, bend;
+ void *page;
+
+ AuTraceEnter();
+
+ err = -ENOMEM;
+ page = (void *)__get_free_page(GFP_TEMPORARY);
+ if (unlikely(!page))
+ goto out;
+
+ err = 0;
+ bend = au_sbend(sb);
+ for (bindex = 0; !err && bindex <= bend; bindex++)
+ if (!bindex || is_sb_shared(sb, bindex, bindex - 1) < 0)
+ err = do_xib_restore
+ (sb, au_sbr(sb, bindex)->br_xino, page);
+ else
+ LKTRTrace("b%d\n", bindex);
+ free_page((unsigned long)page);
+
+ out:
+ AuTraceErr(err);
+ return err;
+}
+
+int au_xib_trunc(struct super_block *sb)
+{
+ int err;
+ struct au_sbinfo *sbinfo;
+ unsigned long *p;
+ loff_t pos;
+ ssize_t sz;
+ struct dentry *parent;
+ struct inode *dir;
+ struct file *file;
+ unsigned int mnt_flags;
+
+ AuTraceEnter();
+ SiMustWriteLock(sb);
+
+ mnt_flags = au_mntflags(sb);
+ if (unlikely(!au_opt_test(mnt_flags, XINO)))
+ return 0;
+
+ sbinfo = au_sbi(sb);
+ parent = dget_parent(sbinfo->si_xib->f_dentry);
+ dir = parent->d_inode;
+ mutex_lock_nested(&dir->i_mutex, AuLsc_I_PARENT);
+ file = au_xino_create2(sb, sbinfo->si_xib, NULL);
+ mutex_unlock(&dir->i_mutex);
+ dput(parent);
+ err = PTR_ERR(file);
+ if (IS_ERR(file))
+ goto out;
+ fput(sbinfo->si_xib);
+ sbinfo->si_xib = file;
+
+ p = sbinfo->si_xib_buf;
+ memset(p, 0, PAGE_SIZE);
+ pos = 0;
+ sz = xino_fwrite(sbinfo->si_xwrite, sbinfo->si_xib, p, PAGE_SIZE, &pos);
+ if (unlikely(sz != PAGE_SIZE)) {
+ err = sz;
+ AuIOErr("err %d\n", err);
+ if (sz >= 0)
+ err = -EIO;
+ goto out;
+ }
+
+ if (au_opt_test(mnt_flags, XINO)) {
+ mutex_lock(&sbinfo->si_xib_mtx);
+ err = xib_restore(sb);
+ mutex_unlock(&sbinfo->si_xib_mtx);
+#if 0 /* reserved for future use */
+ } else {
+ /* is it really safe? */
+ /* dont trust BKL */
+ AuDebugOn(!kernel_locked());
+ ino = AUFS_FIRST_INO;
+ list_for_each_entry(inode, &sb->s_inodes, i_sb_list)
+ if (ino < inode->i_ino)
+ ino = inode->i_ino;
+
+ /* make iunique to return larger than active max inode number */
+ iunique(sb, ino);
+ err = 0;
+#endif
+ }
+
+out:
+ AuTraceErr(err);
+ return err;
+}
+
+/* ---------------------------------------------------------------------- */
+
+/*
+ * xino mount option handlers
+ */
+static au_readf_t find_readf(struct file *h_file)
+{
+ const struct file_operations *fop = h_file->f_op;
+
+ if (fop) {
+ if (fop->read)
+ return fop->read;
+ if (fop->aio_read)
+ return do_sync_read;
+ }
+ return ERR_PTR(-ENOSYS);
+}
+
+static au_writef_t find_writef(struct file *h_file)
+{
+ const struct file_operations *fop = h_file->f_op;
+
+ if (fop) {
+ if (fop->write)
+ return fop->write;
+ if (fop->aio_write)
+ return do_sync_write;
+ }
+ return ERR_PTR(-ENOSYS);
+}
+
+/* xino bitmap */
+static void xino_clear_xib(struct super_block *sb)
+{
+ struct au_sbinfo *sbinfo;
+
+ AuTraceEnter();
+ SiMustWriteLock(sb);
+
+ sbinfo = au_sbi(sb);
+ sbinfo->si_xread = NULL;
+ sbinfo->si_xwrite = NULL;
+ if (sbinfo->si_xib)
+ fput(sbinfo->si_xib);
+ sbinfo->si_xib = NULL;
+ free_page((unsigned long)sbinfo->si_xib_buf);
+ sbinfo->si_xib_buf = NULL;
+}
+
+static int au_xino_set_xib(struct super_block *sb, struct file *base)
+{
+ int err;
+ struct au_sbinfo *sbinfo;
+ struct file *file;
+ loff_t pos;
+
+ LKTRTrace("%.*s\n", AuDLNPair(base->f_dentry));
+ SiMustWriteLock(sb);
+
+ sbinfo = au_sbi(sb);
+ file = au_xino_create2(sb, base, sbinfo->si_xib);
+ err = PTR_ERR(file);
+ if (IS_ERR(file))
+ goto out;
+ if (sbinfo->si_xib)
+ fput(sbinfo->si_xib);
+ sbinfo->si_xib = file;
+ sbinfo->si_xread = find_readf(file);
+ AuDebugOn(IS_ERR(sbinfo->si_xread));
+ sbinfo->si_xwrite = find_writef(file);
+ AuDebugOn(IS_ERR(sbinfo->si_xwrite));
+
+ err = -ENOMEM;
+ if (!sbinfo->si_xib_buf)
+ sbinfo->si_xib_buf = (void *)get_zeroed_page(GFP_KERNEL);
+ if (unlikely(!sbinfo->si_xib_buf))
+ goto out_unset;
+
+ sbinfo->si_xib_last_pindex = 0;
+ sbinfo->si_xib_next_bit = 0;
+
+ /* no need to lock for i_size_read() */
+ if (i_size_read(file->f_dentry->d_inode) < PAGE_SIZE) {
+ pos = 0;
+ err = xino_fwrite(sbinfo->si_xwrite, file, sbinfo->si_xib_buf,
+ PAGE_SIZE, &pos);
+ if (unlikely(err != PAGE_SIZE))
+ goto out_free;
+ }
+ err = 0;
+ goto out; /* success */
+
+ out_free:
+ free_page((unsigned long)sbinfo->si_xib_buf);
+ sbinfo->si_xib_buf = NULL;
+ if (err >= 0)
+ err = -EIO;
+ out_unset:
+ fput(sbinfo->si_xib);
+ sbinfo->si_xib = NULL;
+ sbinfo->si_xread = NULL;
+ sbinfo->si_xwrite = NULL;
+ out:
+ AuTraceErr(err);
+ return err;
+}
+
+/* xino for each branch */
+static void xino_clear_br(struct super_block *sb)
+{
+ aufs_bindex_t bindex, bend;
+ struct au_branch *br;
+
+ AuTraceEnter();
+ SiMustWriteLock(sb);
+
+ bend = au_sbend(sb);
+ for (bindex = 0; bindex <= bend; bindex++) {
+ br = au_sbr(sb, bindex);
+ if (unlikely(!br || !br->br_xino))
+ continue;
+
+ fput(br->br_xino);
+ br->br_xino = NULL;
+ }
+}
+
+static int au_xino_set_br(struct super_block *sb, struct file *base)
+{
+ int err;
+ aufs_bindex_t bindex, bend, bshared;
+ struct {
+ struct file *old, *new;
+ } *fpair, *p;
+ struct au_branch *br;
+ struct au_xino_entry xinoe;
+ struct inode *inode;
+ au_writef_t writef;
+
+ LKTRTrace("%.*s\n", AuDLNPair(base->f_dentry));
+ SiMustWriteLock(sb);
+
+ err = -ENOMEM;
+ bend = au_sbend(sb);
+ fpair = kcalloc(bend + 1, sizeof(*fpair), GFP_TEMPORARY);
+ if (unlikely(!fpair))
+ goto out;
+
+ inode = sb->s_root->d_inode;
+ xinoe.ino = AUFS_ROOT_INO;
+ writef = au_sbi(sb)->si_xwrite;
+ for (bindex = 0, p = fpair; bindex <= bend; bindex++, p++) {
+ br = au_sbr(sb, bindex);
+ bshared = is_sb_shared(sb, bindex, bindex - 1);
+ if (bshared >= 0) {
+ /* shared xino */
+ *p = fpair[bshared];
+ get_file(p->new);
+ }
+
+ if (!p->new) {
+ /* new xino */
+ p->old = br->br_xino;
+ p->new = au_xino_create2(sb, base, br->br_xino);
+ err = PTR_ERR(p->new);
+ if (IS_ERR(p->new)) {
+ p->new = NULL;
+ goto out_pair;
+ }
+ }
+
+ err = au_xino_do_write(writef, p->new,
+ au_h_iptr(inode, bindex)->i_ino, &xinoe);
+ if (unlikely(err))
+ goto out_pair;
+ }
+
+ for (bindex = 0, p = fpair; bindex <= bend; bindex++, p++) {
+ br = au_sbr(sb, bindex);
+ AuDebugOn(p->old != br->br_xino);
+ if (br->br_xino)
+ fput(br->br_xino);
+ get_file(p->new);
+ br->br_xino = p->new;
+ }
+
+ out_pair:
+ for (bindex = 0, p = fpair; bindex <= bend; bindex++, p++)
+ if (p->new)
+ fput(p->new);
+ else
+ break;
+ kfree(fpair);
+ out:
+ AuTraceErr(err);
+ return err;
+}
+
+void au_xino_clr(struct super_block *sb)
+{
+ AuTraceEnter();
+ SiMustWriteLock(sb);
+
+ xino_clear_xib(sb);
+ xino_clear_br(sb);
+ au_opt_clr(au_sbi(sb)->si_mntflags, XINO);
+}
+
+int au_xino_set(struct super_block *sb, struct au_opt_xino *xino, int remount)
+{
+ int err, skip;
+ struct dentry *parent, *cur_parent;
+ struct qstr *dname, *cur_name;
+ struct file *cur_xino;
+ struct inode *dir;
+ struct au_sbinfo *sbinfo;
+
+ LKTRTrace("remount %d\n", remount);
+ SiMustWriteLock(sb);
+
+ err = 0;
+ sbinfo = au_sbi(sb);
+ parent = dget_parent(xino->file->f_dentry);
+ if (remount) {
+ skip = 0;
+ dname = &xino->file->f_dentry->d_name;
+ cur_xino = sbinfo->si_xib;
+ if (cur_xino) {
+ cur_parent = dget_parent(cur_xino->f_dentry);
+ cur_name = &cur_xino->f_dentry->d_name;
+ skip = (cur_parent == parent
+ && dname->len == cur_name->len
+ && !memcmp(dname->name, cur_name->name,
+ dname->len));
+ dput(cur_parent);
+ }
+ if (skip)
+ goto out;
+ }
+
+ au_opt_set(sbinfo->si_mntflags, XINO);
+ dir = parent->d_inode;
+ mutex_lock_nested(&dir->i_mutex, AuLsc_I_PARENT);
+ err = au_xino_set_xib(sb, xino->file);
+ if (!err)
+ err = au_xino_set_br(sb, xino->file);
+ mutex_unlock(&dir->i_mutex);
+ if (!err)
+ goto out; /* success */
+
+ /* reset all */
+ AuIOErr("failed creating xino, forcing noxino (%d).\n", err);
+ err = -EIO;
+ au_xino_clr(sb);
+
+ out:
+ dput(parent);
+ AuTraceErr(err);
+ return err;
+}
+
+int au_xino_trunc(struct super_block *sb, aufs_bindex_t bindex)
+{
+ int err;
+ struct au_branch *br;
+ struct file *new_xino;
+ struct super_block *h_sb;
+ aufs_bindex_t bi, bend;
+ struct dentry *parent;
+ struct inode *dir;
+
+ LKTRTrace("b%d\n", bindex);
+ SiMustWriteLock(sb);
+
+ err = -EINVAL;
+ bend = au_sbend(sb);
+ if (unlikely(bindex < 0 || bend < bindex))
+ goto out;
+ br = au_sbr(sb, bindex);
+ if (unlikely(!br->br_xino))
+ goto out;
+
+ parent = dget_parent(br->br_xino->f_dentry);
+ dir = parent->d_inode;
+ mutex_lock_nested(&dir->i_mutex, AuLsc_I_PARENT);
+ new_xino = au_xino_create2(sb, br->br_xino, br->br_xino);
+ mutex_unlock(&dir->i_mutex);
+ dput(parent);
+ err = PTR_ERR(new_xino);
+ if (IS_ERR(new_xino))
+ goto out;
+ err = 0;
+ fput(br->br_xino);
+ br->br_xino = new_xino;
+
+ h_sb = br->br_mnt->mnt_sb;
+ for (bi = 0; bi <= bend; bi++) {
+ if (unlikely(bi == bindex))
+ continue;
+ br = au_sbr(sb, bi);
+ if (br->br_mnt->mnt_sb != h_sb)
+ continue;
+
+ fput(br->br_xino);
+ br->br_xino = new_xino;
+ get_file(new_xino);
+ }
+
+ out:
+ AuTraceErr(err);
+ return err;
+}
+
+/* ---------------------------------------------------------------------- */
+
+/*
+ * create a xinofile at the default place/path.
+ */
+struct file *au_xino_def(struct super_block *sb)
+{
+ struct file *file;
+ aufs_bindex_t bend, bindex, bwr;
+ char *page, *p;
+ struct path path;
+
+ AuTraceEnter();
+
+ bend = au_sbend(sb);
+ bwr = -1;
+ for (bindex = 0; bindex <= bend; bindex++)
+ if (au_br_writable(au_sbr_perm(sb, bindex))
+ && !au_test_nfs(au_h_dptr(sb->s_root, bindex)->d_sb)) {
+ bwr = bindex;
+ break;
+ }
+
+ if (bwr >= 0) {
+ file = ERR_PTR(-ENOMEM);
+ page = __getname();
+ if (unlikely(!page))
+ goto out;
+ path.mnt = au_sbr_mnt(sb, bwr);
+ path.dentry = au_h_dptr(sb->s_root, bwr);
+ p = d_path(&path, page, PATH_MAX - sizeof(AUFS_XINO_FNAME));
+ file = (void *)p;
+ if (p && !IS_ERR(p)) {
+ strcat(p, "/" AUFS_XINO_FNAME);
+ LKTRTrace("%s\n", p);
+ file = au_xino_create(sb, p, /*silent*/0, sb->s_root);
+ }
+ __putname(page);
+ } else {
+ file = au_xino_create(sb, AUFS_XINO_DEFPATH, /*silent*/0,
+ /*parent*/NULL);
+ if (unlikely(au_test_nfs(file->f_dentry->d_sb))) {
+ AuErr("xino or noxino option is required "
+ "since %s is NFS\n", AUFS_XINO_DEFPATH);
+ fput(file);
+ file = ERR_PTR(-EINVAL);
+ }
+ }
+
+ out:
+ AuTraceErrPtr(file);
+ return file;
+}
--
1.5.5.1.308.g1fbb5.dirty
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