--- /dev/null
+/*
+ * Copyright (C) 2005-2016 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/>.
+ */
+
+/*
+ * copy-up functions, see wbr_policy.c for copy-down
+ */
+
+#include <linux/fs_stack.h>
+#include <linux/mm.h>
+#include <linux/task_work.h>
+#include "aufs.h"
+
+void au_cpup_attr_flags(struct inode *dst, unsigned int iflags)
+{
+ const unsigned int mask = S_DEAD | S_SWAPFILE | S_PRIVATE
+ | S_NOATIME | S_NOCMTIME | S_AUTOMOUNT;
+
+ BUILD_BUG_ON(sizeof(iflags) != sizeof(dst->i_flags));
+
+ dst->i_flags |= iflags & ~mask;
+ if (au_test_fs_notime(dst->i_sb))
+ dst->i_flags |= S_NOATIME | S_NOCMTIME;
+}
+
+void au_cpup_attr_timesizes(struct inode *inode)
+{
+ struct inode *h_inode;
+
+ h_inode = au_h_iptr(inode, au_ibtop(inode));
+ fsstack_copy_attr_times(inode, h_inode);
+ fsstack_copy_inode_size(inode, h_inode);
+}
+
+void au_cpup_attr_nlink(struct inode *inode, int force)
+{
+ struct inode *h_inode;
+ struct super_block *sb;
+ aufs_bindex_t bindex, bbot;
+
+ sb = inode->i_sb;
+ bindex = au_ibtop(inode);
+ h_inode = au_h_iptr(inode, bindex);
+ if (!force
+ && !S_ISDIR(h_inode->i_mode)
+ && au_opt_test(au_mntflags(sb), PLINK)
+ && au_plink_test(inode))
+ return;
+
+ /*
+ * 0 can happen in revalidating.
+ * h_inode->i_mutex may not be held here, but it is harmless since once
+ * i_nlink reaches 0, it will never become positive except O_TMPFILE
+ * case.
+ * todo: O_TMPFILE+linkat(AT_SYMLINK_FOLLOW) bypassing aufs may cause
+ * the incorrect link count.
+ */
+ set_nlink(inode, h_inode->i_nlink);
+
+ /*
+ * fewer nlink makes find(1) noisy, but larger nlink doesn't.
+ * it may includes whplink directory.
+ */
+ if (S_ISDIR(h_inode->i_mode)) {
+ bbot = au_ibbot(inode);
+ for (bindex++; bindex <= bbot; bindex++) {
+ h_inode = au_h_iptr(inode, bindex);
+ if (h_inode)
+ au_add_nlink(inode, h_inode);
+ }
+ }
+}
+
+void au_cpup_attr_changeable(struct inode *inode)
+{
+ struct inode *h_inode;
+
+ h_inode = au_h_iptr(inode, au_ibtop(inode));
+ inode->i_mode = h_inode->i_mode;
+ inode->i_uid = h_inode->i_uid;
+ inode->i_gid = h_inode->i_gid;
+ au_cpup_attr_timesizes(inode);
+ au_cpup_attr_flags(inode, h_inode->i_flags);
+}
+
+void au_cpup_igen(struct inode *inode, struct inode *h_inode)
+{
+ struct au_iinfo *iinfo = au_ii(inode);
+
+ IiMustWriteLock(inode);
+
+ iinfo->ii_higen = h_inode->i_generation;
+ iinfo->ii_hsb1 = h_inode->i_sb;
+}
+
+void au_cpup_attr_all(struct inode *inode, int force)
+{
+ struct inode *h_inode;
+
+ h_inode = au_h_iptr(inode, au_ibtop(inode));
+ au_cpup_attr_changeable(inode);
+ if (inode->i_nlink > 0)
+ au_cpup_attr_nlink(inode, force);
+ inode->i_rdev = h_inode->i_rdev;
+ inode->i_blkbits = h_inode->i_blkbits;
+ au_cpup_igen(inode, h_inode);
+}
+
+/* ---------------------------------------------------------------------- */
+
+/* Note: dt_dentry and dt_h_dentry are not dget/dput-ed */
+
+/* keep the timestamps of the parent dir when cpup */
+void au_dtime_store(struct au_dtime *dt, struct dentry *dentry,
+ struct path *h_path)
+{
+ struct inode *h_inode;
+
+ dt->dt_dentry = dentry;
+ dt->dt_h_path = *h_path;
+ h_inode = d_inode(h_path->dentry);
+ dt->dt_atime = h_inode->i_atime;
+ dt->dt_mtime = h_inode->i_mtime;
+ /* smp_mb(); */
+}
+
+void au_dtime_revert(struct au_dtime *dt)
+{
+ struct iattr attr;
+ int err;
+
+ attr.ia_atime = dt->dt_atime;
+ attr.ia_mtime = dt->dt_mtime;
+ attr.ia_valid = ATTR_FORCE | ATTR_MTIME | ATTR_MTIME_SET
+ | ATTR_ATIME | ATTR_ATIME_SET;
+
+ /* no delegation since this is a directory */
+ err = vfsub_notify_change(&dt->dt_h_path, &attr, /*delegated*/NULL);
+ if (unlikely(err))
+ pr_warn("restoring timestamps failed(%d). ignored\n", err);
+}
+
+/* ---------------------------------------------------------------------- */
+
+/* internal use only */
+struct au_cpup_reg_attr {
+ int valid;
+ struct kstat st;
+ unsigned int iflags; /* inode->i_flags */
+};
+
+static noinline_for_stack
+int cpup_iattr(struct dentry *dst, aufs_bindex_t bindex, struct dentry *h_src,
+ struct au_cpup_reg_attr *h_src_attr)
+{
+ int err, sbits, icex;
+ unsigned int mnt_flags;
+ unsigned char verbose;
+ struct iattr ia;
+ struct path h_path;
+ struct inode *h_isrc, *h_idst;
+ struct kstat *h_st;
+ struct au_branch *br;
+
+ h_path.dentry = au_h_dptr(dst, bindex);
+ h_idst = d_inode(h_path.dentry);
+ br = au_sbr(dst->d_sb, bindex);
+ h_path.mnt = au_br_mnt(br);
+ h_isrc = d_inode(h_src);
+ ia.ia_valid = ATTR_FORCE | ATTR_UID | ATTR_GID
+ | ATTR_ATIME | ATTR_MTIME
+ | ATTR_ATIME_SET | ATTR_MTIME_SET;
+ if (h_src_attr && h_src_attr->valid) {
+ h_st = &h_src_attr->st;
+ ia.ia_uid = h_st->uid;
+ ia.ia_gid = h_st->gid;
+ ia.ia_atime = h_st->atime;
+ ia.ia_mtime = h_st->mtime;
+ if (h_idst->i_mode != h_st->mode
+ && !S_ISLNK(h_idst->i_mode)) {
+ ia.ia_valid |= ATTR_MODE;
+ ia.ia_mode = h_st->mode;
+ }
+ sbits = !!(h_st->mode & (S_ISUID | S_ISGID));
+ au_cpup_attr_flags(h_idst, h_src_attr->iflags);
+ } else {
+ ia.ia_uid = h_isrc->i_uid;
+ ia.ia_gid = h_isrc->i_gid;
+ ia.ia_atime = h_isrc->i_atime;
+ ia.ia_mtime = h_isrc->i_mtime;
+ if (h_idst->i_mode != h_isrc->i_mode
+ && !S_ISLNK(h_idst->i_mode)) {
+ ia.ia_valid |= ATTR_MODE;
+ ia.ia_mode = h_isrc->i_mode;
+ }
+ sbits = !!(h_isrc->i_mode & (S_ISUID | S_ISGID));
+ au_cpup_attr_flags(h_idst, h_isrc->i_flags);
+ }
+ /* no delegation since it is just created */
+ err = vfsub_notify_change(&h_path, &ia, /*delegated*/NULL);
+
+ /* is this nfs only? */
+ if (!err && sbits && au_test_nfs(h_path.dentry->d_sb)) {
+ ia.ia_valid = ATTR_FORCE | ATTR_MODE;
+ ia.ia_mode = h_isrc->i_mode;
+ err = vfsub_notify_change(&h_path, &ia, /*delegated*/NULL);
+ }
+
+ icex = br->br_perm & AuBrAttr_ICEX;
+ if (!err) {
+ mnt_flags = au_mntflags(dst->d_sb);
+ verbose = !!au_opt_test(mnt_flags, VERBOSE);
+ err = au_cpup_xattr(h_path.dentry, h_src, icex, verbose);
+ }
+
+ return err;
+}
+
+/* ---------------------------------------------------------------------- */
+
+static int au_do_copy_file(struct file *dst, struct file *src, loff_t len,
+ char *buf, unsigned long blksize)
+{
+ int err;
+ size_t sz, rbytes, wbytes;
+ unsigned char all_zero;
+ char *p, *zp;
+ struct inode *h_inode;
+ /* reduce stack usage */
+ struct iattr *ia;
+
+ zp = page_address(ZERO_PAGE(0));
+ if (unlikely(!zp))
+ return -ENOMEM; /* possible? */
+
+ err = 0;
+ all_zero = 0;
+ while (len) {
+ AuDbg("len %lld\n", len);
+ sz = blksize;
+ if (len < blksize)
+ sz = len;
+
+ rbytes = 0;
+ /* todo: signal_pending? */
+ while (!rbytes || err == -EAGAIN || err == -EINTR) {
+ rbytes = vfsub_read_k(src, buf, sz, &src->f_pos);
+ err = rbytes;
+ }
+ if (unlikely(err < 0))
+ break;
+
+ all_zero = 0;
+ if (len >= rbytes && rbytes == blksize)
+ all_zero = !memcmp(buf, zp, rbytes);
+ if (!all_zero) {
+ wbytes = rbytes;
+ p = buf;
+ while (wbytes) {
+ size_t b;
+
+ b = vfsub_write_k(dst, p, wbytes, &dst->f_pos);
+ err = b;
+ /* todo: signal_pending? */
+ if (unlikely(err == -EAGAIN || err == -EINTR))
+ continue;
+ if (unlikely(err < 0))
+ break;
+ wbytes -= b;
+ p += b;
+ }
+ if (unlikely(err < 0))
+ break;
+ } else {
+ loff_t res;
+
+ AuLabel(hole);
+ res = vfsub_llseek(dst, rbytes, SEEK_CUR);
+ err = res;
+ if (unlikely(res < 0))
+ break;
+ }
+ len -= rbytes;
+ err = 0;
+ }
+
+ /* the last block may be a hole */
+ if (!err && all_zero) {
+ AuLabel(last hole);
+
+ err = 1;
+ if (au_test_nfs(dst->f_path.dentry->d_sb)) {
+ /* nfs requires this step to make last hole */
+ /* is this only nfs? */
+ do {
+ /* todo: signal_pending? */
+ err = vfsub_write_k(dst, "\0", 1, &dst->f_pos);
+ } while (err == -EAGAIN || err == -EINTR);
+ if (err == 1)
+ dst->f_pos--;
+ }
+
+ if (err == 1) {
+ ia = (void *)buf;
+ ia->ia_size = dst->f_pos;
+ ia->ia_valid = ATTR_SIZE | ATTR_FILE;
+ ia->ia_file = dst;
+ h_inode = file_inode(dst);
+ inode_lock_nested(h_inode, AuLsc_I_CHILD2);
+ /* no delegation since it is just created */
+ err = vfsub_notify_change(&dst->f_path, ia,
+ /*delegated*/NULL);
+ inode_unlock(h_inode);
+ }
+ }
+
+ return err;
+}
+
+int au_copy_file(struct file *dst, struct file *src, loff_t len)
+{
+ int err;
+ unsigned long blksize;
+ unsigned char do_kfree;
+ char *buf;
+
+ err = -ENOMEM;
+ blksize = dst->f_path.dentry->d_sb->s_blocksize;
+ if (!blksize || PAGE_SIZE < blksize)
+ blksize = PAGE_SIZE;
+ AuDbg("blksize %lu\n", blksize);
+ do_kfree = (blksize != PAGE_SIZE && blksize >= sizeof(struct iattr *));
+ if (do_kfree)
+ buf = kmalloc(blksize, GFP_NOFS);
+ else
+ buf = (void *)__get_free_page(GFP_NOFS);
+ if (unlikely(!buf))
+ goto out;
+
+ if (len > (1 << 22))
+ AuDbg("copying a large file %lld\n", (long long)len);
+
+ src->f_pos = 0;
+ dst->f_pos = 0;
+ err = au_do_copy_file(dst, src, len, buf, blksize);
+ if (do_kfree)
+ au_delayed_kfree(buf);
+ else
+ au_delayed_free_page((unsigned long)buf);
+
+out:
+ return err;
+}
+
+/*
+ * to support a sparse file which is opened with O_APPEND,
+ * we need to close the file.
+ */
+static int au_cp_regular(struct au_cp_generic *cpg)
+{
+ int err, i;
+ enum { SRC, DST };
+ struct {
+ aufs_bindex_t bindex;
+ unsigned int flags;
+ struct dentry *dentry;
+ int force_wr;
+ struct file *file;
+ void *label;
+ } *f, file[] = {
+ {
+ .bindex = cpg->bsrc,
+ .flags = O_RDONLY | O_NOATIME | O_LARGEFILE,
+ .label = &&out
+ },
+ {
+ .bindex = cpg->bdst,
+ .flags = O_WRONLY | O_NOATIME | O_LARGEFILE,
+ .force_wr = !!au_ftest_cpup(cpg->flags, RWDST),
+ .label = &&out_src
+ }
+ };
+ struct super_block *sb;
+ struct inode *h_src_inode;
+ struct task_struct *tsk = current;
+
+ /* bsrc branch can be ro/rw. */
+ sb = cpg->dentry->d_sb;
+ f = file;
+ for (i = 0; i < 2; i++, f++) {
+ f->dentry = au_h_dptr(cpg->dentry, f->bindex);
+ f->file = au_h_open(cpg->dentry, f->bindex, f->flags,
+ /*file*/NULL, f->force_wr);
+ err = PTR_ERR(f->file);
+ if (IS_ERR(f->file))
+ goto *f->label;
+ }
+
+ /* try stopping to update while we copyup */
+ h_src_inode = d_inode(file[SRC].dentry);
+ if (!au_test_nfs(h_src_inode->i_sb))
+ IMustLock(h_src_inode);
+ err = au_copy_file(file[DST].file, file[SRC].file, cpg->len);
+
+ /* i wonder if we had O_NO_DELAY_FPUT flag */
+ if (tsk->flags & PF_KTHREAD)
+ __fput_sync(file[DST].file);
+ else {
+ WARN(1, "%pD\nPlease report this warning to aufs-users ML",
+ file[DST].file);
+ fput(file[DST].file);
+ /*
+ * too bad.
+ * we have to call both since we don't know which place the file
+ * was added to.
+ */
+ task_work_run();
+ flush_delayed_fput();
+ }
+ au_sbr_put(sb, file[DST].bindex);
+
+out_src:
+ fput(file[SRC].file);
+ au_sbr_put(sb, file[SRC].bindex);
+out:
+ return err;
+}
+
+static int au_do_cpup_regular(struct au_cp_generic *cpg,
+ struct au_cpup_reg_attr *h_src_attr)
+{
+ int err, rerr;
+ loff_t l;
+ struct path h_path;
+ struct inode *h_src_inode, *h_dst_inode;
+
+ err = 0;
+ h_src_inode = au_h_iptr(d_inode(cpg->dentry), cpg->bsrc);
+ l = i_size_read(h_src_inode);
+ if (cpg->len == -1 || l < cpg->len)
+ cpg->len = l;
+ if (cpg->len) {
+ /* try stopping to update while we are referencing */
+ inode_lock_nested(h_src_inode, AuLsc_I_CHILD);
+ au_pin_hdir_unlock(cpg->pin);
+
+ h_path.dentry = au_h_dptr(cpg->dentry, cpg->bsrc);
+ h_path.mnt = au_sbr_mnt(cpg->dentry->d_sb, cpg->bsrc);
+ h_src_attr->iflags = h_src_inode->i_flags;
+ if (!au_test_nfs(h_src_inode->i_sb))
+ err = vfs_getattr(&h_path, &h_src_attr->st);
+ else {
+ inode_unlock(h_src_inode);
+ err = vfs_getattr(&h_path, &h_src_attr->st);
+ inode_lock_nested(h_src_inode, AuLsc_I_CHILD);
+ }
+ if (unlikely(err)) {
+ inode_unlock(h_src_inode);
+ goto out;
+ }
+ h_src_attr->valid = 1;
+ if (!au_test_nfs(h_src_inode->i_sb)) {
+ err = au_cp_regular(cpg);
+ inode_unlock(h_src_inode);
+ } else {
+ inode_unlock(h_src_inode);
+ err = au_cp_regular(cpg);
+ }
+ rerr = au_pin_hdir_relock(cpg->pin);
+ if (!err && rerr)
+ err = rerr;
+ }
+ if (!err && (h_src_inode->i_state & I_LINKABLE)) {
+ h_path.dentry = au_h_dptr(cpg->dentry, cpg->bdst);
+ h_dst_inode = d_inode(h_path.dentry);
+ spin_lock(&h_dst_inode->i_lock);
+ h_dst_inode->i_state |= I_LINKABLE;
+ spin_unlock(&h_dst_inode->i_lock);
+ }
+
+out:
+ return err;
+}
+
+static int au_do_cpup_symlink(struct path *h_path, struct dentry *h_src,
+ struct inode *h_dir)
+{
+ int err, symlen;
+ mm_segment_t old_fs;
+ union {
+ char *k;
+ char __user *u;
+ } sym;
+ struct inode *h_inode = d_inode(h_src);
+ const struct inode_operations *h_iop = h_inode->i_op;
+
+ err = -ENOSYS;
+ if (unlikely(!h_iop->readlink))
+ goto out;
+
+ err = -ENOMEM;
+ sym.k = (void *)__get_free_page(GFP_NOFS);
+ if (unlikely(!sym.k))
+ goto out;
+
+ /* unnecessary to support mmap_sem since symlink is not mmap-able */
+ old_fs = get_fs();
+ set_fs(KERNEL_DS);
+ symlen = h_iop->readlink(h_src, sym.u, PATH_MAX);
+ err = symlen;
+ set_fs(old_fs);
+
+ if (symlen > 0) {
+ sym.k[symlen] = 0;
+ err = vfsub_symlink(h_dir, h_path, sym.k);
+ }
+ au_delayed_free_page((unsigned long)sym.k);
+
+out:
+ return err;
+}
+
+/*
+ * regardless 'acl' option, reset all ACL.
+ * All ACL will be copied up later from the original entry on the lower branch.
+ */
+static int au_reset_acl(struct inode *h_dir, struct path *h_path, umode_t mode)
+{
+ int err;
+ struct dentry *h_dentry;
+ struct inode *h_inode;
+
+ h_dentry = h_path->dentry;
+ h_inode = d_inode(h_dentry);
+ /* forget_all_cached_acls(h_inode)); */
+ err = vfsub_removexattr(h_dentry, XATTR_NAME_POSIX_ACL_ACCESS);
+ AuTraceErr(err);
+ if (err == -EOPNOTSUPP)
+ err = 0;
+ if (!err)
+ err = vfsub_acl_chmod(h_inode, mode);
+
+ AuTraceErr(err);
+ return err;
+}
+
+static int au_do_cpup_dir(struct au_cp_generic *cpg, struct dentry *dst_parent,
+ struct inode *h_dir, struct path *h_path)
+{
+ int err;
+ struct inode *dir, *inode;
+
+ err = vfsub_removexattr(h_path->dentry, XATTR_NAME_POSIX_ACL_DEFAULT);
+ AuTraceErr(err);
+ if (err == -EOPNOTSUPP)
+ err = 0;
+ if (unlikely(err))
+ goto out;
+
+ /*
+ * strange behaviour from the users view,
+ * particularry setattr case
+ */
+ dir = d_inode(dst_parent);
+ if (au_ibtop(dir) == cpg->bdst)
+ au_cpup_attr_nlink(dir, /*force*/1);
+ inode = d_inode(cpg->dentry);
+ au_cpup_attr_nlink(inode, /*force*/1);
+
+out:
+ return err;
+}
+
+static noinline_for_stack
+int cpup_entry(struct au_cp_generic *cpg, struct dentry *dst_parent,
+ struct au_cpup_reg_attr *h_src_attr)
+{
+ int err;
+ umode_t mode;
+ unsigned int mnt_flags;
+ unsigned char isdir, isreg, force;
+ const unsigned char do_dt = !!au_ftest_cpup(cpg->flags, DTIME);
+ struct au_dtime dt;
+ struct path h_path;
+ struct dentry *h_src, *h_dst, *h_parent;
+ struct inode *h_inode, *h_dir;
+ struct super_block *sb;
+
+ /* bsrc branch can be ro/rw. */
+ h_src = au_h_dptr(cpg->dentry, cpg->bsrc);
+ h_inode = d_inode(h_src);
+ AuDebugOn(h_inode != au_h_iptr(d_inode(cpg->dentry), cpg->bsrc));
+
+ /* try stopping to be referenced while we are creating */
+ h_dst = au_h_dptr(cpg->dentry, cpg->bdst);
+ if (au_ftest_cpup(cpg->flags, RENAME))
+ AuDebugOn(strncmp(h_dst->d_name.name, AUFS_WH_PFX,
+ AUFS_WH_PFX_LEN));
+ h_parent = h_dst->d_parent; /* dir inode is locked */
+ h_dir = d_inode(h_parent);
+ IMustLock(h_dir);
+ AuDebugOn(h_parent != h_dst->d_parent);
+
+ sb = cpg->dentry->d_sb;
+ h_path.mnt = au_sbr_mnt(sb, cpg->bdst);
+ if (do_dt) {
+ h_path.dentry = h_parent;
+ au_dtime_store(&dt, dst_parent, &h_path);
+ }
+ h_path.dentry = h_dst;
+
+ isreg = 0;
+ isdir = 0;
+ mode = h_inode->i_mode;
+ switch (mode & S_IFMT) {
+ case S_IFREG:
+ isreg = 1;
+ err = vfsub_create(h_dir, &h_path, S_IRUSR | S_IWUSR,
+ /*want_excl*/true);
+ if (!err)
+ err = au_do_cpup_regular(cpg, h_src_attr);
+ break;
+ case S_IFDIR:
+ isdir = 1;
+ err = vfsub_mkdir(h_dir, &h_path, mode);
+ if (!err)
+ err = au_do_cpup_dir(cpg, dst_parent, h_dir, &h_path);
+ break;
+ case S_IFLNK:
+ err = au_do_cpup_symlink(&h_path, h_src, h_dir);
+ break;
+ case S_IFCHR:
+ case S_IFBLK:
+ AuDebugOn(!capable(CAP_MKNOD));
+ /*FALLTHROUGH*/
+ case S_IFIFO:
+ case S_IFSOCK:
+ err = vfsub_mknod(h_dir, &h_path, mode, h_inode->i_rdev);
+ break;
+ default:
+ AuIOErr("Unknown inode type 0%o\n", mode);
+ err = -EIO;
+ }
+ if (!err)
+ err = au_reset_acl(h_dir, &h_path, mode);
+
+ mnt_flags = au_mntflags(sb);
+ if (!au_opt_test(mnt_flags, UDBA_NONE)
+ && !isdir
+ && au_opt_test(mnt_flags, XINO)
+ && (h_inode->i_nlink == 1
+ || (h_inode->i_state & I_LINKABLE))
+ /* todo: unnecessary? */
+ /* && d_inode(cpg->dentry)->i_nlink == 1 */
+ && cpg->bdst < cpg->bsrc
+ && !au_ftest_cpup(cpg->flags, KEEPLINO))
+ au_xino_write(sb, cpg->bsrc, h_inode->i_ino, /*ino*/0);
+ /* ignore this error */
+
+ if (!err) {
+ force = 0;
+ if (isreg) {
+ force = !!cpg->len;
+ if (cpg->len == -1)
+ force = !!i_size_read(h_inode);
+ }
+ au_fhsm_wrote(sb, cpg->bdst, force);
+ }
+
+ if (do_dt)
+ au_dtime_revert(&dt);
+ return err;
+}
+
+static int au_do_ren_after_cpup(struct au_cp_generic *cpg, struct path *h_path)
+{
+ int err;
+ struct dentry *dentry, *h_dentry, *h_parent, *parent;
+ struct inode *h_dir;
+ aufs_bindex_t bdst;
+
+ dentry = cpg->dentry;
+ bdst = cpg->bdst;
+ h_dentry = au_h_dptr(dentry, bdst);
+ if (!au_ftest_cpup(cpg->flags, OVERWRITE)) {
+ dget(h_dentry);
+ au_set_h_dptr(dentry, bdst, NULL);
+ err = au_lkup_neg(dentry, bdst, /*wh*/0);
+ if (!err)
+ h_path->dentry = dget(au_h_dptr(dentry, bdst));
+ au_set_h_dptr(dentry, bdst, h_dentry);
+ } else {
+ err = 0;
+ parent = dget_parent(dentry);
+ h_parent = au_h_dptr(parent, bdst);
+ dput(parent);
+ h_path->dentry = vfsub_lkup_one(&dentry->d_name, h_parent);
+ if (IS_ERR(h_path->dentry))
+ err = PTR_ERR(h_path->dentry);
+ }
+ if (unlikely(err))
+ goto out;
+
+ h_parent = h_dentry->d_parent; /* dir inode is locked */
+ h_dir = d_inode(h_parent);
+ IMustLock(h_dir);
+ AuDbg("%pd %pd\n", h_dentry, h_path->dentry);
+ /* no delegation since it is just created */
+ err = vfsub_rename(h_dir, h_dentry, h_dir, h_path, /*delegated*/NULL);
+ dput(h_path->dentry);
+
+out:
+ return err;
+}
+
+/*
+ * copyup the @dentry from @bsrc to @bdst.
+ * the caller must set the both of lower dentries.
+ * @len is for truncating when it is -1 copyup the entire file.
+ * in link/rename cases, @dst_parent may be different from the real one.
+ * basic->bsrc can be larger than basic->bdst.
+ */
+static int au_cpup_single(struct au_cp_generic *cpg, struct dentry *dst_parent)
+{
+ int err, rerr;
+ aufs_bindex_t old_ibtop;
+ unsigned char isdir, plink;
+ struct dentry *h_src, *h_dst, *h_parent;
+ struct inode *dst_inode, *h_dir, *inode, *delegated, *src_inode;
+ struct super_block *sb;
+ struct au_branch *br;
+ /* to reuduce stack size */
+ struct {
+ struct au_dtime dt;
+ struct path h_path;
+ struct au_cpup_reg_attr h_src_attr;
+ } *a;
+
+ err = -ENOMEM;
+ a = kmalloc(sizeof(*a), GFP_NOFS);
+ if (unlikely(!a))
+ goto out;
+ a->h_src_attr.valid = 0;
+
+ sb = cpg->dentry->d_sb;
+ br = au_sbr(sb, cpg->bdst);
+ a->h_path.mnt = au_br_mnt(br);
+ h_dst = au_h_dptr(cpg->dentry, cpg->bdst);
+ h_parent = h_dst->d_parent; /* dir inode is locked */
+ h_dir = d_inode(h_parent);
+ IMustLock(h_dir);
+
+ h_src = au_h_dptr(cpg->dentry, cpg->bsrc);
+ inode = d_inode(cpg->dentry);
+
+ if (!dst_parent)
+ dst_parent = dget_parent(cpg->dentry);
+ else
+ dget(dst_parent);
+
+ plink = !!au_opt_test(au_mntflags(sb), PLINK);
+ dst_inode = au_h_iptr(inode, cpg->bdst);
+ if (dst_inode) {
+ if (unlikely(!plink)) {
+ err = -EIO;
+ AuIOErr("hi%lu(i%lu) exists on b%d "
+ "but plink is disabled\n",
+ dst_inode->i_ino, inode->i_ino, cpg->bdst);
+ goto out_parent;
+ }
+
+ if (dst_inode->i_nlink) {
+ const int do_dt = au_ftest_cpup(cpg->flags, DTIME);
+
+ h_src = au_plink_lkup(inode, cpg->bdst);
+ err = PTR_ERR(h_src);
+ if (IS_ERR(h_src))
+ goto out_parent;
+ if (unlikely(d_is_negative(h_src))) {
+ err = -EIO;
+ AuIOErr("i%lu exists on b%d "
+ "but not pseudo-linked\n",
+ inode->i_ino, cpg->bdst);
+ dput(h_src);
+ goto out_parent;
+ }
+
+ if (do_dt) {
+ a->h_path.dentry = h_parent;
+ au_dtime_store(&a->dt, dst_parent, &a->h_path);
+ }
+
+ a->h_path.dentry = h_dst;
+ delegated = NULL;
+ err = vfsub_link(h_src, h_dir, &a->h_path, &delegated);
+ if (!err && au_ftest_cpup(cpg->flags, RENAME))
+ err = au_do_ren_after_cpup(cpg, &a->h_path);
+ if (do_dt)
+ au_dtime_revert(&a->dt);
+ if (unlikely(err == -EWOULDBLOCK)) {
+ pr_warn("cannot retry for NFSv4 delegation"
+ " for an internal link\n");
+ iput(delegated);
+ }
+ dput(h_src);
+ goto out_parent;
+ } else
+ /* todo: cpup_wh_file? */
+ /* udba work */
+ au_update_ibrange(inode, /*do_put_zero*/1);
+ }
+
+ isdir = S_ISDIR(inode->i_mode);
+ old_ibtop = au_ibtop(inode);
+ err = cpup_entry(cpg, dst_parent, &a->h_src_attr);
+ if (unlikely(err))
+ goto out_rev;
+ dst_inode = d_inode(h_dst);
+ inode_lock_nested(dst_inode, AuLsc_I_CHILD2);
+ /* todo: necessary? */
+ /* au_pin_hdir_unlock(cpg->pin); */
+
+ err = cpup_iattr(cpg->dentry, cpg->bdst, h_src, &a->h_src_attr);
+ if (unlikely(err)) {
+ /* todo: necessary? */
+ /* au_pin_hdir_relock(cpg->pin); */ /* ignore an error */
+ inode_unlock(dst_inode);
+ goto out_rev;
+ }
+
+ if (cpg->bdst < old_ibtop) {
+ if (S_ISREG(inode->i_mode)) {
+ err = au_dy_iaop(inode, cpg->bdst, dst_inode);
+ if (unlikely(err)) {
+ /* ignore an error */
+ /* au_pin_hdir_relock(cpg->pin); */
+ inode_unlock(dst_inode);
+ goto out_rev;
+ }
+ }
+ au_set_ibtop(inode, cpg->bdst);
+ } else
+ au_set_ibbot(inode, cpg->bdst);
+ au_set_h_iptr(inode, cpg->bdst, au_igrab(dst_inode),
+ au_hi_flags(inode, isdir));
+
+ /* todo: necessary? */
+ /* err = au_pin_hdir_relock(cpg->pin); */
+ inode_unlock(dst_inode);
+ if (unlikely(err))
+ goto out_rev;
+
+ src_inode = d_inode(h_src);
+ if (!isdir
+ && (src_inode->i_nlink > 1
+ || src_inode->i_state & I_LINKABLE)
+ && plink)
+ au_plink_append(inode, cpg->bdst, h_dst);
+
+ if (au_ftest_cpup(cpg->flags, RENAME)) {
+ a->h_path.dentry = h_dst;
+ err = au_do_ren_after_cpup(cpg, &a->h_path);
+ }
+ if (!err)
+ goto out_parent; /* success */
+
+ /* revert */
+out_rev:
+ a->h_path.dentry = h_parent;
+ au_dtime_store(&a->dt, dst_parent, &a->h_path);
+ a->h_path.dentry = h_dst;
+ rerr = 0;
+ if (d_is_positive(h_dst)) {
+ if (!isdir) {
+ /* no delegation since it is just created */
+ rerr = vfsub_unlink(h_dir, &a->h_path,
+ /*delegated*/NULL, /*force*/0);
+ } else
+ rerr = vfsub_rmdir(h_dir, &a->h_path);
+ }
+ au_dtime_revert(&a->dt);
+ if (rerr) {
+ AuIOErr("failed removing broken entry(%d, %d)\n", err, rerr);
+ err = -EIO;
+ }
+out_parent:
+ dput(dst_parent);
+ au_delayed_kfree(a);
+out:
+ return err;
+}
+
+#if 0 /* reserved */
+struct au_cpup_single_args {
+ int *errp;
+ struct au_cp_generic *cpg;
+ struct dentry *dst_parent;
+};
+
+static void au_call_cpup_single(void *args)
+{
+ struct au_cpup_single_args *a = args;
+
+ au_pin_hdir_acquire_nest(a->cpg->pin);
+ *a->errp = au_cpup_single(a->cpg, a->dst_parent);
+ au_pin_hdir_release(a->cpg->pin);
+}
+#endif
+
+/*
+ * prevent SIGXFSZ in copy-up.
+ * testing CAP_MKNOD is for generic fs,
+ * but CAP_FSETID is for xfs only, currently.
+ */
+static int au_cpup_sio_test(struct au_pin *pin, umode_t mode)
+{
+ int do_sio;
+ struct super_block *sb;
+ struct inode *h_dir;
+
+ do_sio = 0;
+ sb = au_pinned_parent(pin)->d_sb;
+ if (!au_wkq_test()
+ && (!au_sbi(sb)->si_plink_maint_pid
+ || au_plink_maint(sb, AuLock_NOPLM))) {
+ switch (mode & S_IFMT) {
+ case S_IFREG:
+ /* no condition about RLIMIT_FSIZE and the file size */
+ do_sio = 1;
+ break;
+ case S_IFCHR:
+ case S_IFBLK:
+ do_sio = !capable(CAP_MKNOD);
+ break;
+ }
+ if (!do_sio)
+ do_sio = ((mode & (S_ISUID | S_ISGID))
+ && !capable(CAP_FSETID));
+ /* this workaround may be removed in the future */
+ if (!do_sio) {
+ h_dir = au_pinned_h_dir(pin);
+ do_sio = h_dir->i_mode & S_ISVTX;
+ }
+ }
+
+ return do_sio;
+}
+
+#if 0 /* reserved */
+int au_sio_cpup_single(struct au_cp_generic *cpg, struct dentry *dst_parent)
+{
+ int err, wkq_err;
+ struct dentry *h_dentry;
+
+ h_dentry = au_h_dptr(cpg->dentry, cpg->bsrc);
+ if (!au_cpup_sio_test(pin, d_inode(h_dentry)->i_mode))
+ err = au_cpup_single(cpg, dst_parent);
+ else {
+ struct au_cpup_single_args args = {
+ .errp = &err,
+ .cpg = cpg,
+ .dst_parent = dst_parent
+ };
+ wkq_err = au_wkq_wait(au_call_cpup_single, &args);
+ if (unlikely(wkq_err))
+ err = wkq_err;
+ }
+
+ return err;
+}
+#endif
+
+/*
+ * copyup the @dentry from the first active lower branch to @bdst,
+ * using au_cpup_single().
+ */
+static int au_cpup_simple(struct au_cp_generic *cpg)
+{
+ int err;
+ unsigned int flags_orig;
+ struct dentry *dentry;
+
+ AuDebugOn(cpg->bsrc < 0);
+
+ dentry = cpg->dentry;
+ DiMustWriteLock(dentry);
+
+ err = au_lkup_neg(dentry, cpg->bdst, /*wh*/1);
+ if (!err) {
+ flags_orig = cpg->flags;
+ au_fset_cpup(cpg->flags, RENAME);
+ err = au_cpup_single(cpg, NULL);
+ cpg->flags = flags_orig;
+ if (!err)
+ return 0; /* success */
+
+ /* revert */
+ au_set_h_dptr(dentry, cpg->bdst, NULL);
+ au_set_dbtop(dentry, cpg->bsrc);
+ }
+
+ return err;
+}
+
+struct au_cpup_simple_args {
+ int *errp;
+ struct au_cp_generic *cpg;
+};
+
+static void au_call_cpup_simple(void *args)
+{
+ struct au_cpup_simple_args *a = args;
+
+ au_pin_hdir_acquire_nest(a->cpg->pin);
+ *a->errp = au_cpup_simple(a->cpg);
+ au_pin_hdir_release(a->cpg->pin);
+}
+
+static int au_do_sio_cpup_simple(struct au_cp_generic *cpg)
+{
+ int err, wkq_err;
+ struct dentry *dentry, *parent;
+ struct file *h_file;
+ struct inode *h_dir;
+
+ dentry = cpg->dentry;
+ h_file = NULL;
+ if (au_ftest_cpup(cpg->flags, HOPEN)) {
+ AuDebugOn(cpg->bsrc < 0);
+ h_file = au_h_open_pre(dentry, cpg->bsrc, /*force_wr*/0);
+ err = PTR_ERR(h_file);
+ if (IS_ERR(h_file))
+ goto out;
+ }
+
+ parent = dget_parent(dentry);
+ h_dir = au_h_iptr(d_inode(parent), cpg->bdst);
+ if (!au_test_h_perm_sio(h_dir, MAY_EXEC | MAY_WRITE)
+ && !au_cpup_sio_test(cpg->pin, d_inode(dentry)->i_mode))
+ err = au_cpup_simple(cpg);
+ else {
+ struct au_cpup_simple_args args = {
+ .errp = &err,
+ .cpg = cpg
+ };
+ wkq_err = au_wkq_wait(au_call_cpup_simple, &args);
+ if (unlikely(wkq_err))
+ err = wkq_err;
+ }
+
+ dput(parent);
+ if (h_file)
+ au_h_open_post(dentry, cpg->bsrc, h_file);
+
+out:
+ return err;
+}
+
+int au_sio_cpup_simple(struct au_cp_generic *cpg)
+{
+ aufs_bindex_t bsrc, bbot;
+ struct dentry *dentry, *h_dentry;
+
+ if (cpg->bsrc < 0) {
+ dentry = cpg->dentry;
+ bbot = au_dbbot(dentry);
+ for (bsrc = cpg->bdst + 1; bsrc <= bbot; bsrc++) {
+ h_dentry = au_h_dptr(dentry, bsrc);
+ if (h_dentry) {
+ AuDebugOn(d_is_negative(h_dentry));
+ break;
+ }
+ }
+ AuDebugOn(bsrc > bbot);
+ cpg->bsrc = bsrc;
+ }
+ AuDebugOn(cpg->bsrc <= cpg->bdst);
+ return au_do_sio_cpup_simple(cpg);
+}
+
+int au_sio_cpdown_simple(struct au_cp_generic *cpg)
+{
+ AuDebugOn(cpg->bdst <= cpg->bsrc);
+ return au_do_sio_cpup_simple(cpg);
+}
+
+/* ---------------------------------------------------------------------- */
+
+/*
+ * copyup the deleted file for writing.
+ */
+static int au_do_cpup_wh(struct au_cp_generic *cpg, struct dentry *wh_dentry,
+ struct file *file)
+{
+ int err;
+ unsigned int flags_orig;
+ aufs_bindex_t bsrc_orig;
+ struct au_dinfo *dinfo;
+ struct {
+ struct au_hdentry *hd;
+ struct dentry *h_dentry;
+ } hdst, hsrc;
+
+ dinfo = au_di(cpg->dentry);
+ AuRwMustWriteLock(&dinfo->di_rwsem);
+
+ bsrc_orig = cpg->bsrc;
+ cpg->bsrc = dinfo->di_btop;
+ hdst.hd = au_hdentry(dinfo, cpg->bdst);
+ hdst.h_dentry = hdst.hd->hd_dentry;
+ hdst.hd->hd_dentry = wh_dentry;
+ dinfo->di_btop = cpg->bdst;
+
+ hsrc.h_dentry = NULL;
+ if (file) {
+ hsrc.hd = au_hdentry(dinfo, cpg->bsrc);
+ hsrc.h_dentry = hsrc.hd->hd_dentry;
+ hsrc.hd->hd_dentry = au_hf_top(file)->f_path.dentry;
+ }
+ flags_orig = cpg->flags;
+ cpg->flags = !AuCpup_DTIME;
+ err = au_cpup_single(cpg, /*h_parent*/NULL);
+ cpg->flags = flags_orig;
+ if (file) {
+ if (!err)
+ err = au_reopen_nondir(file);
+ hsrc.hd->hd_dentry = hsrc.h_dentry;
+ }
+ hdst.hd->hd_dentry = hdst.h_dentry;
+ dinfo->di_btop = cpg->bsrc;
+ cpg->bsrc = bsrc_orig;
+
+ return err;
+}
+
+static int au_cpup_wh(struct au_cp_generic *cpg, struct file *file)
+{
+ int err;
+ aufs_bindex_t bdst;
+ struct au_dtime dt;
+ struct dentry *dentry, *parent, *h_parent, *wh_dentry;
+ struct au_branch *br;
+ struct path h_path;
+
+ dentry = cpg->dentry;
+ bdst = cpg->bdst;
+ br = au_sbr(dentry->d_sb, bdst);
+ parent = dget_parent(dentry);
+ h_parent = au_h_dptr(parent, bdst);
+ wh_dentry = au_whtmp_lkup(h_parent, br, &dentry->d_name);
+ err = PTR_ERR(wh_dentry);
+ if (IS_ERR(wh_dentry))
+ goto out;
+
+ h_path.dentry = h_parent;
+ h_path.mnt = au_br_mnt(br);
+ au_dtime_store(&dt, parent, &h_path);
+ err = au_do_cpup_wh(cpg, wh_dentry, file);
+ if (unlikely(err))
+ goto out_wh;
+
+ dget(wh_dentry);
+ h_path.dentry = wh_dentry;
+ if (!d_is_dir(wh_dentry)) {
+ /* no delegation since it is just created */
+ err = vfsub_unlink(d_inode(h_parent), &h_path,
+ /*delegated*/NULL, /*force*/0);
+ } else
+ err = vfsub_rmdir(d_inode(h_parent), &h_path);
+ if (unlikely(err)) {
+ AuIOErr("failed remove copied-up tmp file %pd(%d)\n",
+ wh_dentry, err);
+ err = -EIO;
+ }
+ au_dtime_revert(&dt);
+ au_set_hi_wh(d_inode(dentry), bdst, wh_dentry);
+
+out_wh:
+ dput(wh_dentry);
+out:
+ dput(parent);
+ return err;
+}
+
+struct au_cpup_wh_args {
+ int *errp;
+ struct au_cp_generic *cpg;
+ struct file *file;
+};
+
+static void au_call_cpup_wh(void *args)
+{
+ struct au_cpup_wh_args *a = args;
+
+ au_pin_hdir_acquire_nest(a->cpg->pin);
+ *a->errp = au_cpup_wh(a->cpg, a->file);
+ au_pin_hdir_release(a->cpg->pin);
+}
+
+int au_sio_cpup_wh(struct au_cp_generic *cpg, struct file *file)
+{
+ int err, wkq_err;
+ aufs_bindex_t bdst;
+ struct dentry *dentry, *parent, *h_orph, *h_parent;
+ struct inode *dir, *h_dir, *h_tmpdir;
+ struct au_wbr *wbr;
+ struct au_pin wh_pin, *pin_orig;
+
+ dentry = cpg->dentry;
+ bdst = cpg->bdst;
+ parent = dget_parent(dentry);
+ dir = d_inode(parent);
+ h_orph = NULL;
+ h_parent = NULL;
+ h_dir = au_igrab(au_h_iptr(dir, bdst));
+ h_tmpdir = h_dir;
+ pin_orig = NULL;
+ if (!h_dir->i_nlink) {
+ wbr = au_sbr(dentry->d_sb, bdst)->br_wbr;
+ h_orph = wbr->wbr_orph;
+
+ h_parent = dget(au_h_dptr(parent, bdst));
+ au_set_h_dptr(parent, bdst, dget(h_orph));
+ h_tmpdir = d_inode(h_orph);
+ au_set_h_iptr(dir, bdst, au_igrab(h_tmpdir), /*flags*/0);
+
+ inode_lock_nested(h_tmpdir, AuLsc_I_PARENT3);
+ /* todo: au_h_open_pre()? */
+
+ pin_orig = cpg->pin;
+ au_pin_init(&wh_pin, dentry, bdst, AuLsc_DI_PARENT,
+ AuLsc_I_PARENT3, cpg->pin->udba, AuPin_DI_LOCKED);
+ cpg->pin = &wh_pin;
+ }
+
+ if (!au_test_h_perm_sio(h_tmpdir, MAY_EXEC | MAY_WRITE)
+ && !au_cpup_sio_test(cpg->pin, d_inode(dentry)->i_mode))
+ err = au_cpup_wh(cpg, file);
+ else {
+ struct au_cpup_wh_args args = {
+ .errp = &err,
+ .cpg = cpg,
+ .file = file
+ };
+ wkq_err = au_wkq_wait(au_call_cpup_wh, &args);
+ if (unlikely(wkq_err))
+ err = wkq_err;
+ }
+
+ if (h_orph) {
+ inode_unlock(h_tmpdir);
+ /* todo: au_h_open_post()? */
+ au_set_h_iptr(dir, bdst, au_igrab(h_dir), /*flags*/0);
+ au_set_h_dptr(parent, bdst, h_parent);
+ AuDebugOn(!pin_orig);
+ cpg->pin = pin_orig;
+ }
+ iput(h_dir);
+ dput(parent);
+
+ return err;
+}
+
+/* ---------------------------------------------------------------------- */
+
+/*
+ * generic routine for both of copy-up and copy-down.
+ */
+/* cf. revalidate function in file.c */
+int au_cp_dirs(struct dentry *dentry, aufs_bindex_t bdst,
+ int (*cp)(struct dentry *dentry, aufs_bindex_t bdst,
+ struct au_pin *pin,
+ struct dentry *h_parent, void *arg),
+ void *arg)
+{
+ int err;
+ struct au_pin pin;
+ struct dentry *d, *parent, *h_parent, *real_parent, *h_dentry;
+
+ err = 0;
+ parent = dget_parent(dentry);
+ if (IS_ROOT(parent))
+ goto out;
+
+ au_pin_init(&pin, dentry, bdst, AuLsc_DI_PARENT2, AuLsc_I_PARENT2,
+ au_opt_udba(dentry->d_sb), AuPin_MNT_WRITE);
+
+ /* do not use au_dpage */
+ real_parent = parent;
+ while (1) {
+ dput(parent);
+ parent = dget_parent(dentry);
+ h_parent = au_h_dptr(parent, bdst);
+ if (h_parent)
+ goto out; /* success */
+
+ /* find top dir which is necessary to cpup */
+ do {
+ d = parent;
+ dput(parent);
+ parent = dget_parent(d);
+ di_read_lock_parent3(parent, !AuLock_IR);
+ h_parent = au_h_dptr(parent, bdst);
+ di_read_unlock(parent, !AuLock_IR);
+ } while (!h_parent);
+
+ if (d != real_parent)
+ di_write_lock_child3(d);
+
+ /* somebody else might create while we were sleeping */
+ h_dentry = au_h_dptr(d, bdst);
+ if (!h_dentry || d_is_negative(h_dentry)) {
+ if (h_dentry)
+ au_update_dbtop(d);
+
+ au_pin_set_dentry(&pin, d);
+ err = au_do_pin(&pin);
+ if (!err) {
+ err = cp(d, bdst, &pin, h_parent, arg);
+ au_unpin(&pin);
+ }
+ }
+
+ if (d != real_parent)
+ di_write_unlock(d);
+ if (unlikely(err))
+ break;
+ }
+
+out:
+ dput(parent);
+ return err;
+}
+
+static int au_cpup_dir(struct dentry *dentry, aufs_bindex_t bdst,
+ struct au_pin *pin,
+ struct dentry *h_parent __maybe_unused,
+ void *arg __maybe_unused)
+{
+ struct au_cp_generic cpg = {
+ .dentry = dentry,
+ .bdst = bdst,
+ .bsrc = -1,
+ .len = 0,
+ .pin = pin,
+ .flags = AuCpup_DTIME
+ };
+ return au_sio_cpup_simple(&cpg);
+}
+
+int au_cpup_dirs(struct dentry *dentry, aufs_bindex_t bdst)
+{
+ return au_cp_dirs(dentry, bdst, au_cpup_dir, NULL);
+}
+
+int au_test_and_cpup_dirs(struct dentry *dentry, aufs_bindex_t bdst)
+{
+ int err;
+ struct dentry *parent;
+ struct inode *dir;
+
+ parent = dget_parent(dentry);
+ dir = d_inode(parent);
+ err = 0;
+ if (au_h_iptr(dir, bdst))
+ goto out;
+
+ di_read_unlock(parent, AuLock_IR);
+ di_write_lock_parent(parent);
+ /* someone else might change our inode while we were sleeping */
+ if (!au_h_iptr(dir, bdst))
+ err = au_cpup_dirs(dentry, bdst);
+ di_downgrade_lock(parent, AuLock_IR);
+
+out:
+ dput(parent);
+ return err;
+}
projects / mirror_ubuntu-zesty-kernel.git / blobdiff