diff -Nur linux-2.6.31.5.orig/Documentation/ABI/testing/debugfs-aufs linux-2.6.31.5/Documentation/ABI/testing/debugfs-aufs --- linux-2.6.31.5.orig/Documentation/ABI/testing/debugfs-aufs 1970-01-01 01:00:00.000000000 +0100 +++ linux-2.6.31.5/Documentation/ABI/testing/debugfs-aufs 2009-11-15 22:02:37.000000000 +0100 @@ -0,0 +1,40 @@ +What: /debug/aufs/si_<id>/ +Date: March 2009 +Contact: J. R. Okajima <hooanon05@yahoo.co.jp> +Description: + Under /debug/aufs, a directory named si_<id> is created + per aufs mount, where <id> is a unique id generated + internally. + +What: /debug/aufs/si_<id>/xib +Date: March 2009 +Contact: J. R. Okajima <hooanon05@yahoo.co.jp> +Description: + It shows the consumed blocks by xib (External Inode Number + Bitmap), its block size and file size. + When the aufs mount option 'noxino' is specified, it + will be empty. About XINO files, see + Documentation/filesystems/aufs/aufs.5 in detail. + +What: /debug/aufs/si_<id>/xino0, xino1 ... xinoN +Date: March 2009 +Contact: J. R. Okajima <hooanon05@yahoo.co.jp> +Description: + It shows the consumed blocks by xino (External Inode Number + Translation Table), its link count, block size and file + size. + When the aufs mount option 'noxino' is specified, it + will be empty. About XINO files, see + Documentation/filesystems/aufs/aufs.5 in detail. + +What: /debug/aufs/si_<id>/xigen +Date: March 2009 +Contact: J. R. Okajima <hooanon05@yahoo.co.jp> +Description: + It shows the consumed blocks by xigen (External Inode + Generation Table), its block size and file size. + If CONFIG_AUFS_EXPORT is disabled, this entry will not + be created. + When the aufs mount option 'noxino' is specified, it + will be empty. About XINO files, see + Documentation/filesystems/aufs/aufs.5 in detail. diff -Nur linux-2.6.31.5.orig/Documentation/ABI/testing/sysfs-aufs linux-2.6.31.5/Documentation/ABI/testing/sysfs-aufs --- linux-2.6.31.5.orig/Documentation/ABI/testing/sysfs-aufs 1970-01-01 01:00:00.000000000 +0100 +++ linux-2.6.31.5/Documentation/ABI/testing/sysfs-aufs 2009-11-15 22:02:37.000000000 +0100 @@ -0,0 +1,25 @@ +What: /sys/fs/aufs/si_<id>/ +Date: March 2009 +Contact: J. R. Okajima <hooanon05@yahoo.co.jp> +Description: + Under /sys/fs/aufs, a directory named si_<id> is created + per aufs mount, where <id> is a unique id generated + internally. + +What: /sys/fs/aufs/si_<id>/br0, br1 ... brN +Date: March 2009 +Contact: J. R. Okajima <hooanon05@yahoo.co.jp> +Description: + It shows the abolute path of a member directory (which + is called branch) in aufs, and its permission. + +What: /sys/fs/aufs/si_<id>/xi_path +Date: March 2009 +Contact: J. R. Okajima <hooanon05@yahoo.co.jp> +Description: + It shows the abolute path of XINO (External Inode Number + Bitmap, Translation Table and Generation Table) file + even if it is the default path. + When the aufs mount option 'noxino' is specified, it + will be empty. About XINO files, see + Documentation/filesystems/aufs/aufs.5 in detail. diff -Nur linux-2.6.31.5.orig/fs/aufs/aufs.h linux-2.6.31.5/fs/aufs/aufs.h --- linux-2.6.31.5.orig/fs/aufs/aufs.h 1970-01-01 01:00:00.000000000 +0100 +++ linux-2.6.31.5/fs/aufs/aufs.h 2009-11-15 22:02:37.000000000 +0100 @@ -0,0 +1,51 @@ +/* + * Copyright (C) 2005-2009 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, write to the Free Software + * Foundation, Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA + */ + +/* + * all header files + */ + +#ifndef __AUFS_H__ +#define __AUFS_H__ + +#ifdef __KERNEL__ + +#include "debug.h" + +#include "branch.h" +#include "cpup.h" +#include "dcsub.h" +#include "dbgaufs.h" +#include "dentry.h" +#include "dir.h" +#include "file.h" +#include "fstype.h" +#include "inode.h" +#include "loop.h" +#include "module.h" +#include "opts.h" +#include "rwsem.h" +#include "spl.h" +#include "super.h" +#include "sysaufs.h" +#include "vfsub.h" +#include "whout.h" +#include "wkq.h" + +#endif /* __KERNEL__ */ +#endif /* __AUFS_H__ */ diff -Nur linux-2.6.31.5.orig/fs/aufs/branch.c linux-2.6.31.5/fs/aufs/branch.c --- linux-2.6.31.5.orig/fs/aufs/branch.c 1970-01-01 01:00:00.000000000 +0100 +++ linux-2.6.31.5/fs/aufs/branch.c 2009-11-15 22:02:37.000000000 +0100 @@ -0,0 +1,974 @@ +/* + * Copyright (C) 2005-2009 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, write to the Free Software + * Foundation, Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA + */ + +/* + * branch management + */ + +#include <linux/file.h> +#include "aufs.h" + +/* + * free a single branch + */ +static void au_br_do_free(struct au_branch *br) +{ + int i; + struct au_wbr *wbr; + + if (br->br_xino.xi_file) + fput(br->br_xino.xi_file); + mutex_destroy(&br->br_xino.xi_nondir_mtx); + + AuDebugOn(atomic_read(&br->br_count)); + + wbr = br->br_wbr; + if (wbr) { + for (i = 0; i < AuBrWh_Last; i++) + dput(wbr->wbr_wh[i]); + AuDebugOn(atomic_read(&wbr->wbr_wh_running)); + AuRwDestroy(&wbr->wbr_wh_rwsem); + } + + /* some filesystems acquire extra lock */ + lockdep_off(); + mntput(br->br_mnt); + lockdep_on(); + + kfree(wbr); + kfree(br); +} + +/* + * frees all branches + */ +void au_br_free(struct au_sbinfo *sbinfo) +{ + aufs_bindex_t bmax; + struct au_branch **br; + + AuRwMustWriteLock(&sbinfo->si_rwsem); + + bmax = sbinfo->si_bend + 1; + br = sbinfo->si_branch; + while (bmax--) + au_br_do_free(*br++); +} + +/* + * find the index of a branch which is specified by @br_id. + */ +int au_br_index(struct super_block *sb, aufs_bindex_t br_id) +{ + aufs_bindex_t bindex, bend; + + bend = au_sbend(sb); + for (bindex = 0; bindex <= bend; bindex++) + if (au_sbr_id(sb, bindex) == br_id) + return bindex; + return -1; +} + +/* ---------------------------------------------------------------------- */ + +/* + * add a branch + */ + +static int test_overlap(struct super_block *sb, struct dentry *h_d1, + struct dentry *h_d2) +{ + if (unlikely(h_d1 == h_d2)) + return 1; + return !!au_test_subdir(h_d1, h_d2) + || !!au_test_subdir(h_d2, h_d1) + || au_test_loopback_overlap(sb, h_d1, h_d2) + || au_test_loopback_overlap(sb, h_d2, h_d1); +} + +/* + * returns a newly allocated branch. @new_nbranch is a number of branches + * after adding a branch. + */ +static struct au_branch *au_br_alloc(struct super_block *sb, int new_nbranch, + int perm) +{ + struct au_branch *add_branch; + struct dentry *root; + + root = sb->s_root; + add_branch = kmalloc(sizeof(*add_branch), GFP_NOFS); + if (unlikely(!add_branch)) + goto out; + + add_branch->br_wbr = NULL; + if (au_br_writable(perm)) { + /* may be freed separately at changing the branch permission */ + add_branch->br_wbr = kmalloc(sizeof(*add_branch->br_wbr), + GFP_NOFS); + if (unlikely(!add_branch->br_wbr)) + goto out_br; + } + + if (unlikely(au_sbr_realloc(au_sbi(sb), new_nbranch) + || au_di_realloc(au_di(root), new_nbranch) + || au_ii_realloc(au_ii(root->d_inode), new_nbranch))) + goto out_wbr; + return add_branch; /* success */ + + out_wbr: + kfree(add_branch->br_wbr); + out_br: + kfree(add_branch); + out: + return ERR_PTR(-ENOMEM); +} + +/* + * test if the branch permission is legal or not. + */ +static int test_br(struct inode *inode, int brperm, char *path) +{ + int err; + + err = 0; + if (unlikely(au_br_writable(brperm) && IS_RDONLY(inode))) { + AuErr("write permission for readonly mount or inode, %s\n", + path); + err = -EINVAL; + } + + return err; +} + +/* + * returns: + * 0: success, the caller will add it + * plus: success, it is already unified, the caller should ignore it + * minus: error + */ +static int test_add(struct super_block *sb, struct au_opt_add *add, int remount) +{ + int err; + aufs_bindex_t bend, bindex; + struct dentry *root; + struct inode *inode, *h_inode; + + root = sb->s_root; + bend = au_sbend(sb); + if (unlikely(bend >= 0 + && au_find_dbindex(root, add->path.dentry) >= 0)) { + err = 1; + if (!remount) { + err = -EINVAL; + AuErr("%s duplicated\n", add->pathname); + } + goto out; + } + + err = -ENOSPC; /* -E2BIG; */ + if (unlikely(AUFS_BRANCH_MAX <= add->bindex + || AUFS_BRANCH_MAX - 1 <= bend)) { + AuErr("number of branches exceeded %s\n", add->pathname); + goto out; + } + + err = -EDOM; + if (unlikely(add->bindex < 0 || bend + 1 < add->bindex)) { + AuErr("bad index %d\n", add->bindex); + goto out; + } + + inode = add->path.dentry->d_inode; + err = -ENOENT; + if (unlikely(!inode->i_nlink)) { + AuErr("no existence %s\n", add->pathname); + goto out; + } + + err = -EINVAL; + if (unlikely(inode->i_sb == sb)) { + AuErr("%s must be outside\n", add->pathname); + goto out; + } + + if (unlikely(au_test_fs_unsuppoted(inode->i_sb))) { + AuErr("unsupported filesystem, %s (%s)\n", + add->pathname, au_sbtype(inode->i_sb)); + goto out; + } + + err = test_br(add->path.dentry->d_inode, add->perm, add->pathname); + if (unlikely(err)) + goto out; + + if (bend < 0) + return 0; /* success */ + + err = -EINVAL; + for (bindex = 0; bindex <= bend; bindex++) + if (unlikely(test_overlap(sb, add->path.dentry, + au_h_dptr(root, bindex)))) { + AuErr("%s is overlapped\n", add->pathname); + goto out; + } + + err = 0; + if (au_opt_test(au_mntflags(sb), WARN_PERM)) { + h_inode = au_h_dptr(root, 0)->d_inode; + if ((h_inode->i_mode & S_IALLUGO) != (inode->i_mode & S_IALLUGO) + || h_inode->i_uid != inode->i_uid + || h_inode->i_gid != inode->i_gid) + AuWarn("uid/gid/perm %s %u/%u/0%o, %u/%u/0%o\n", + add->pathname, + inode->i_uid, inode->i_gid, + (inode->i_mode & S_IALLUGO), + h_inode->i_uid, h_inode->i_gid, + (h_inode->i_mode & S_IALLUGO)); + } + + out: + return err; +} + +/* + * initialize or clean the whiteouts for an adding branch + */ +static int au_br_init_wh(struct super_block *sb, struct au_branch *br, + int new_perm, struct dentry *h_root) +{ + int err, old_perm; + aufs_bindex_t bindex; + struct mutex *h_mtx; + struct au_wbr *wbr; + struct au_hinode *hdir; + + wbr = br->br_wbr; + old_perm = br->br_perm; + br->br_perm = new_perm; + hdir = NULL; + h_mtx = NULL; + bindex = au_br_index(sb, br->br_id); + if (0 <= bindex) { + hdir = au_hi(sb->s_root->d_inode, bindex); + au_hin_imtx_lock_nested(hdir, AuLsc_I_PARENT); + } else { + h_mtx = &h_root->d_inode->i_mutex; + mutex_lock_nested(h_mtx, AuLsc_I_PARENT); + } + if (!wbr) + err = au_wh_init(h_root, br, sb); + else { + wbr_wh_write_lock(wbr); + err = au_wh_init(h_root, br, sb); + wbr_wh_write_unlock(wbr); + } + if (hdir) + au_hin_imtx_unlock(hdir); + else + mutex_unlock(h_mtx); + br->br_perm = old_perm; + + if (!err && wbr && !au_br_writable(new_perm)) { + kfree(wbr); + br->br_wbr = NULL; + } + + return err; +} + +static int au_wbr_init(struct au_branch *br, struct super_block *sb, + int perm, struct path *path) +{ + int err; + struct au_wbr *wbr; + + wbr = br->br_wbr; + au_rw_init(&wbr->wbr_wh_rwsem); + memset(wbr->wbr_wh, 0, sizeof(wbr->wbr_wh)); + atomic_set(&wbr->wbr_wh_running, 0); + wbr->wbr_bytes = 0; + + err = au_br_init_wh(sb, br, perm, path->dentry); + + return err; +} + +/* intialize a new branch */ +static int au_br_init(struct au_branch *br, struct super_block *sb, + struct au_opt_add *add) +{ + int err; + + err = 0; + memset(&br->br_xino, 0, sizeof(br->br_xino)); + mutex_init(&br->br_xino.xi_nondir_mtx); + br->br_perm = add->perm; + br->br_mnt = add->path.mnt; /* set first, mntget() later */ + atomic_set(&br->br_count, 0); + br->br_xino_upper = AUFS_XINO_TRUNC_INIT; + atomic_set(&br->br_xino_running, 0); + br->br_id = au_new_br_id(sb); + + if (au_br_writable(add->perm)) { + err = au_wbr_init(br, sb, add->perm, &add->path); + if (unlikely(err)) + goto out; + } + + if (au_opt_test(au_mntflags(sb), XINO)) { + err = au_xino_br(sb, br, add->path.dentry->d_inode->i_ino, + au_sbr(sb, 0)->br_xino.xi_file, /*do_test*/1); + if (unlikely(err)) { + AuDebugOn(br->br_xino.xi_file); + goto out; + } + } + + sysaufs_br_init(br); + mntget(add->path.mnt); + + out: + return err; +} + +static void au_br_do_add_brp(struct au_sbinfo *sbinfo, aufs_bindex_t bindex, + struct au_branch *br, aufs_bindex_t bend, + aufs_bindex_t amount) +{ + struct au_branch **brp; + + AuRwMustWriteLock(&sbinfo->si_rwsem); + + brp = sbinfo->si_branch + bindex; + memmove(brp + 1, brp, sizeof(*brp) * amount); + *brp = br; + sbinfo->si_bend++; + if (unlikely(bend < 0)) + sbinfo->si_bend = 0; +} + +static void au_br_do_add_hdp(struct au_dinfo *dinfo, aufs_bindex_t bindex, + aufs_bindex_t bend, aufs_bindex_t amount) +{ + struct au_hdentry *hdp; + + AuRwMustWriteLock(&dinfo->di_rwsem); + + hdp = dinfo->di_hdentry + bindex; + memmove(hdp + 1, hdp, sizeof(*hdp) * amount); + au_h_dentry_init(hdp); + dinfo->di_bend++; + if (unlikely(bend < 0)) + dinfo->di_bstart = 0; +} + +static void au_br_do_add_hip(struct au_iinfo *iinfo, aufs_bindex_t bindex, + aufs_bindex_t bend, aufs_bindex_t amount) +{ + struct au_hinode *hip; + + AuRwMustWriteLock(&iinfo->ii_rwsem); + + hip = iinfo->ii_hinode + bindex; + memmove(hip + 1, hip, sizeof(*hip) * amount); + hip->hi_inode = NULL; + au_hin_init(hip, NULL); + iinfo->ii_bend++; + if (unlikely(bend < 0)) + iinfo->ii_bstart = 0; +} + +static void au_br_do_add(struct super_block *sb, struct dentry *h_dentry, + struct au_branch *br, aufs_bindex_t bindex) +{ + struct dentry *root; + struct inode *root_inode; + aufs_bindex_t bend, amount; + + root = sb->s_root; + root_inode = root->d_inode; + au_plink_block_maintain(sb); + bend = au_sbend(sb); + amount = bend + 1 - bindex; + au_br_do_add_brp(au_sbi(sb), bindex, br, bend, amount); + au_br_do_add_hdp(au_di(root), bindex, bend, amount); + au_br_do_add_hip(au_ii(root_inode), bindex, bend, amount); + au_set_h_dptr(root, bindex, dget(h_dentry)); + au_set_h_iptr(root_inode, bindex, au_igrab(h_dentry->d_inode), + /*flags*/0); +} + +int au_br_add(struct super_block *sb, struct au_opt_add *add, int remount) +{ + int err; + unsigned long long maxb; + aufs_bindex_t bend, add_bindex; + struct dentry *root, *h_dentry; + struct inode *root_inode; + struct au_branch *add_branch; + + root = sb->s_root; + root_inode = root->d_inode; + IMustLock(root_inode); + err = test_add(sb, add, remount); + if (unlikely(err < 0)) + goto out; + if (err) { + err = 0; + goto out; /* success */ + } + + bend = au_sbend(sb); + add_branch = au_br_alloc(sb, bend + 2, add->perm); + err = PTR_ERR(add_branch); + if (IS_ERR(add_branch)) + goto out; + + err = au_br_init(add_branch, sb, add); + if (unlikely(err)) { + au_br_do_free(add_branch); + goto out; + } + + add_bindex = add->bindex; + h_dentry = add->path.dentry; + if (!remount) + au_br_do_add(sb, h_dentry, add_branch, add_bindex); + else { + sysaufs_brs_del(sb, add_bindex); + au_br_do_add(sb, h_dentry, add_branch, add_bindex); + sysaufs_brs_add(sb, add_bindex); + } + + if (!add_bindex) + au_cpup_attr_all(root_inode, /*force*/1); + else + au_add_nlink(root_inode, h_dentry->d_inode); + maxb = h_dentry->d_sb->s_maxbytes; + if (sb->s_maxbytes < maxb) + sb->s_maxbytes = maxb; + + /* + * this test/set prevents aufs from handling unnecesary inotify events + * of xino files, in a case of re-adding a writable branch which was + * once detached from aufs. + */ + if (au_xino_brid(sb) < 0 + && au_br_writable(add_branch->br_perm) + && !au_test_fs_bad_xino(h_dentry->d_sb) + && add_branch->br_xino.xi_file + && add_branch->br_xino.xi_file->f_dentry->d_parent == h_dentry) + au_xino_brid_set(sb, add_branch->br_id); + + out: + return err; +} + +/* ---------------------------------------------------------------------- */ + +/* + * delete a branch + */ + +/* to show the line number, do not make it inlined function */ +#define AuVerbose(do_info, fmt, args...) do { \ + if (do_info) \ + AuInfo(fmt, ##args); \ +} while (0) + +/* + * test if the branch is deletable or not. + */ +static int test_dentry_busy(struct dentry *root, aufs_bindex_t bindex, + unsigned int sigen) +{ + int err, i, j, ndentry; + aufs_bindex_t bstart, bend; + unsigned char verbose; + struct au_dcsub_pages dpages; + struct au_dpage *dpage; + struct dentry *d; + struct inode *inode; + + err = au_dpages_init(&dpages, GFP_NOFS); + if (unlikely(err)) + goto out; + err = au_dcsub_pages(&dpages, root, NULL, NULL); + if (unlikely(err)) + goto out_dpages; + + verbose = !!au_opt_test(au_mntflags(root->d_sb), VERBOSE); + for (i = 0; !err && i < dpages.ndpage; i++) { + dpage = dpages.dpages + i; + ndentry = dpage->ndentry; + for (j = 0; !err && j < ndentry; j++) { + d = dpage->dentries[j]; + AuDebugOn(!atomic_read(&d->d_count)); + inode = d->d_inode; + if (au_digen(d) == sigen && au_iigen(inode) == sigen) + di_read_lock_child(d, AuLock_IR); + else { + di_write_lock_child(d); + err = au_reval_dpath(d, sigen); + if (!err) + di_downgrade_lock(d, AuLock_IR); + else { + di_write_unlock(d); + break; + } + } + + bstart = au_dbstart(d); + bend = au_dbend(d); + if (bstart <= bindex + && bindex <= bend + && au_h_dptr(d, bindex) + && (!S_ISDIR(inode->i_mode) || bstart == bend)) { + err = -EBUSY; + AuVerbose(verbose, "busy %.*s\n", AuDLNPair(d)); + } + di_read_unlock(d, AuLock_IR); + } + } + + out_dpages: + au_dpages_free(&dpages); + out: + return err; +} + +static int test_inode_busy(struct super_block *sb, aufs_bindex_t bindex, + unsigned int sigen) +{ + int err; + struct inode *i; + aufs_bindex_t bstart, bend; + unsigned char verbose; + + err = 0; + verbose = !!au_opt_test(au_mntflags(sb), VERBOSE); + list_for_each_entry(i, &sb->s_inodes, i_sb_list) { + AuDebugOn(!atomic_read(&i->i_count)); + if (!list_empty(&i->i_dentry)) + continue; + + if (au_iigen(i) == sigen) + ii_read_lock_child(i); + else { + ii_write_lock_child(i); + err = au_refresh_hinode_self(i, /*do_attr*/1); + if (!err) + ii_downgrade_lock(i); + else { + ii_write_unlock(i); + break; + } + } + + bstart = au_ibstart(i); + bend = au_ibend(i); + if (bstart <= bindex + && bindex <= bend + && au_h_iptr(i, bindex) + && (!S_ISDIR(i->i_mode) || bstart == bend)) { + err = -EBUSY; + AuVerbose(verbose, "busy i%lu\n", i->i_ino); + ii_read_unlock(i); + break; + } + ii_read_unlock(i); + } + + return err; +} + +static int test_children_busy(struct dentry *root, aufs_bindex_t bindex) +{ + int err; + unsigned int sigen; + + sigen = au_sigen(root->d_sb); + DiMustNoWaiters(root); + IiMustNoWaiters(root->d_inode); + di_write_unlock(root); + err = test_dentry_busy(root, bindex, sigen); + if (!err) + err = test_inode_busy(root->d_sb, bindex, sigen); + di_write_lock_child(root); /* aufs_write_lock() calls ..._child() */ + + return err; +} + +static void au_br_do_del_brp(struct au_sbinfo *sbinfo, + const aufs_bindex_t bindex, + const aufs_bindex_t bend) +{ + struct au_branch **brp, **p; + + AuRwMustWriteLock(&sbinfo->si_rwsem); + + brp = sbinfo->si_branch + bindex; + if (bindex < bend) + memmove(brp, brp + 1, sizeof(*brp) * (bend - bindex)); + sbinfo->si_branch[0 + bend] = NULL; + sbinfo->si_bend--; + + p = krealloc(sbinfo->si_branch, sizeof(*p) * bend, GFP_NOFS); + if (p) + sbinfo->si_branch = p; +} + +static void au_br_do_del_hdp(struct au_dinfo *dinfo, const aufs_bindex_t bindex, + const aufs_bindex_t bend) +{ + struct au_hdentry *hdp, *p; + + AuRwMustWriteLock(&dinfo->di_rwsem); + + hdp = dinfo->di_hdentry + bindex; + if (bindex < bend) + memmove(hdp, hdp + 1, sizeof(*hdp) * (bend - bindex)); + dinfo->di_hdentry[0 + bend].hd_dentry = NULL; + dinfo->di_bend--; + + p = krealloc(dinfo->di_hdentry, sizeof(*p) * bend, GFP_NOFS); + if (p) + dinfo->di_hdentry = p; +} + +static void au_br_do_del_hip(struct au_iinfo *iinfo, const aufs_bindex_t bindex, + const aufs_bindex_t bend) +{ + struct au_hinode *hip, *p; + + AuRwMustWriteLock(&iinfo->ii_rwsem); + + hip = iinfo->ii_hinode + bindex; + if (bindex < bend) + memmove(hip, hip + 1, sizeof(*hip) * (bend - bindex)); + iinfo->ii_hinode[0 + bend].hi_inode = NULL; + au_hin_init(iinfo->ii_hinode + bend, NULL); + iinfo->ii_bend--; + + p = krealloc(iinfo->ii_hinode, sizeof(*p) * bend, GFP_NOFS); + if (p) + iinfo->ii_hinode = p; +} + +static void au_br_do_del(struct super_block *sb, aufs_bindex_t bindex, + struct au_branch *br) +{ + aufs_bindex_t bend; + struct au_sbinfo *sbinfo; + struct dentry *root; + struct inode *inode; + + SiMustWriteLock(sb); + + root = sb->s_root; + inode = root->d_inode; + au_plink_block_maintain(sb); + sbinfo = au_sbi(sb); + bend = sbinfo->si_bend; + + dput(au_h_dptr(root, bindex)); + au_hiput(au_hi(inode, bindex)); + au_br_do_free(br); + + au_br_do_del_brp(sbinfo, bindex, bend); + au_br_do_del_hdp(au_di(root), bindex, bend); + au_br_do_del_hip(au_ii(inode), bindex, bend); +} + +int au_br_del(struct super_block *sb, struct au_opt_del *del, int remount) +{ + int err, rerr, i; + unsigned int mnt_flags; + aufs_bindex_t bindex, bend, br_id; + unsigned char do_wh, verbose; + struct au_branch *br; + struct au_wbr *wbr; + + err = 0; + bindex = au_find_dbindex(sb->s_root, del->h_path.dentry); + if (bindex < 0) { + if (remount) + goto out; /* success */ + err = -ENOENT; + AuErr("%s no such branch\n", del->pathname); + goto out; + } + AuDbg("bindex b%d\n", bindex); + + err = -EBUSY; + mnt_flags = au_mntflags(sb); + verbose = !!au_opt_test(mnt_flags, VERBOSE); + bend = au_sbend(sb); + if (unlikely(!bend)) { + AuVerbose(verbose, "no more branches left\n"); + goto out; + } + br = au_sbr(sb, bindex); + i = atomic_read(&br->br_count); + if (unlikely(i)) { + AuVerbose(verbose, "%d file(s) opened\n", i); + goto out; + } + + wbr = br->br_wbr; + do_wh = wbr && (wbr->wbr_whbase || wbr->wbr_plink || wbr->wbr_orph); + if (do_wh) { + /* instead of WbrWhMustWriteLock(wbr) */ + SiMustWriteLock(sb); + for (i = 0; i < AuBrWh_Last; i++) { + dput(wbr->wbr_wh[i]); + wbr->wbr_wh[i] = NULL; + } + } + + err = test_children_busy(sb->s_root, bindex); + if (unlikely(err)) { + if (do_wh) + goto out_wh; + goto out; + } + + err = 0; + br_id = br->br_id; + if (!remount) + au_br_do_del(sb, bindex, br); + else { + sysaufs_brs_del(sb, bindex); + au_br_do_del(sb, bindex, br); + sysaufs_brs_add(sb, bindex); + } + + if (!bindex) + au_cpup_attr_all(sb->s_root->d_inode, /*force*/1); + else + au_sub_nlink(sb->s_root->d_inode, del->h_path.dentry->d_inode); + if (au_opt_test(mnt_flags, PLINK)) + au_plink_half_refresh(sb, br_id); + + if (sb->s_maxbytes == del->h_path.dentry->d_sb->s_maxbytes) { + bend--; + sb->s_maxbytes = 0; + for (bindex = 0; bindex <= bend; bindex++) { + unsigned long long maxb; + + maxb = au_sbr_sb(sb, bindex)->s_maxbytes; + if (sb->s_maxbytes < maxb) + sb->s_maxbytes = maxb; + } + } + + if (au_xino_brid(sb) == br->br_id) + au_xino_brid_set(sb, -1); + goto out; /* success */ + + out_wh: + /* revert */ + rerr = au_br_init_wh(sb, br, br->br_perm, del->h_path.dentry); + if (rerr) + AuWarn("failed re-creating base whiteout, %s. (%d)\n", + del->pathname, rerr); + out: + return err; +} + +/* ---------------------------------------------------------------------- */ + +/* + * change a branch permission + */ + +static int do_need_sigen_inc(int a, int b) +{ + return au_br_whable(a) && !au_br_whable(b); +} + +static int need_sigen_inc(int old, int new) +{ + return do_need_sigen_inc(old, new) + || do_need_sigen_inc(new, old); +} + +static int au_br_mod_files_ro(struct super_block *sb, aufs_bindex_t bindex) +{ + int err; + unsigned long n, ul, bytes, files; + aufs_bindex_t bstart; + struct file *file, *hf, **a; + const int step_bytes = 1024, /* memory allocation unit */ + step_files = step_bytes / sizeof(*a); + + err = -ENOMEM; + n = 0; + bytes = step_bytes; + files = step_files; + a = kmalloc(bytes, GFP_NOFS); + if (unlikely(!a)) + goto out; + + /* no need file_list_lock() since sbinfo is locked? defered? */ + list_for_each_entry(file, &sb->s_files, f_u.fu_list) { + if (special_file(file->f_dentry->d_inode->i_mode)) + continue; + + AuDbg("%.*s\n", AuDLNPair(file->f_dentry)); + fi_read_lock(file); + if (unlikely(au_test_mmapped(file))) { + err = -EBUSY; + FiMustNoWaiters(file); + fi_read_unlock(file); + goto out_free; + } + + bstart = au_fbstart(file); + if (!S_ISREG(file->f_dentry->d_inode->i_mode) + || !(file->f_mode & FMODE_WRITE) + || bstart != bindex) { + FiMustNoWaiters(file); + fi_read_unlock(file); + continue; + } + + hf = au_h_fptr(file, bstart); + FiMustNoWaiters(file); + fi_read_unlock(file); + + if (n < files) + a[n++] = hf; + else { + void *p; + + err = -ENOMEM; + bytes += step_bytes; + files += step_files; + p = krealloc(a, bytes, GFP_NOFS); + if (p) { + a = p; + a[n++] = hf; + } else + goto out_free; + } + } + + err = 0; + for (ul = 0; ul < n; ul++) { + /* todo: already flushed? */ + /* cf. fs/super.c:mark_files_ro() */ + hf = a[ul]; + hf->f_mode &= ~FMODE_WRITE; + if (!file_check_writeable(hf)) { + file_release_write(hf); + mnt_drop_write(hf->f_vfsmnt); + } + } + + out_free: + kfree(a); + out: + return err; +} + +int au_br_mod(struct super_block *sb, struct au_opt_mod *mod, int remount, + int *do_update) +{ + int err, rerr; + aufs_bindex_t bindex; + struct dentry *root; + struct au_branch *br; + + root = sb->s_root; + au_plink_block_maintain(sb); + bindex = au_find_dbindex(root, mod->h_root); + if (bindex < 0) { + if (remount) + return 0; /* success */ + err = -ENOENT; + AuErr("%s no such branch\n", mod->path); + goto out; + } + AuDbg("bindex b%d\n", bindex); + + err = test_br(mod->h_root->d_inode, mod->perm, mod->path); + if (unlikely(err)) + goto out; + + br = au_sbr(sb, bindex); + if (br->br_perm == mod->perm) + return 0; /* success */ + + if (au_br_writable(br->br_perm)) { + /* remove whiteout base */ + err = au_br_init_wh(sb, br, mod->perm, mod->h_root); + if (unlikely(err)) + goto out; + + if (!au_br_writable(mod->perm)) { + /* rw --> ro, file might be mmapped */ + DiMustNoWaiters(root); + IiMustNoWaiters(root->d_inode); + di_write_unlock(root); + err = au_br_mod_files_ro(sb, bindex); + /* aufs_write_lock() calls ..._child() */ + di_write_lock_child(root); + + if (unlikely(err)) { + rerr = -ENOMEM; + br->br_wbr = kmalloc(sizeof(*br->br_wbr), + GFP_NOFS); + if (br->br_wbr) + rerr = au_br_init_wh + (sb, br, br->br_perm, + mod->h_root); + if (unlikely(rerr)) { + AuIOErr("nested error %d (%d)\n", + rerr, err); + br->br_perm = mod->perm; + } + } + } + } else if (au_br_writable(mod->perm)) { + /* ro --> rw */ + err = -ENOMEM; + br->br_wbr = kmalloc(sizeof(*br->br_wbr), GFP_NOFS); + if (br->br_wbr) { + struct path path = { + .mnt = br->br_mnt, + .dentry = mod->h_root + }; + + err = au_wbr_init(br, sb, mod->perm, &path); + if (unlikely(err)) { + kfree(br->br_wbr); + br->br_wbr = NULL; + } + } + } + + if (!err) { + *do_update |= need_sigen_inc(br->br_perm, mod->perm); + br->br_perm = mod->perm; + } + + out: + return err; +} diff -Nur linux-2.6.31.5.orig/fs/aufs/branch.h linux-2.6.31.5/fs/aufs/branch.h --- linux-2.6.31.5.orig/fs/aufs/branch.h 1970-01-01 01:00:00.000000000 +0100 +++ linux-2.6.31.5/fs/aufs/branch.h 2009-11-15 22:02:37.000000000 +0100 @@ -0,0 +1,219 @@ +/* + * Copyright (C) 2005-2009 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, write to the Free Software + * Foundation, Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA + */ + +/* + * branch filesystems and xino for them + */ + +#ifndef __AUFS_BRANCH_H__ +#define __AUFS_BRANCH_H__ + +#ifdef __KERNEL__ + +#include <linux/fs.h> +#include <linux/mount.h> +#include <linux/aufs_type.h> +#include "rwsem.h" +#include "super.h" + +/* ---------------------------------------------------------------------- */ + +/* a xino file */ +struct au_xino_file { + struct file *xi_file; + struct mutex xi_nondir_mtx; + + /* todo: make xino files an array to support huge inode number */ + +#ifdef CONFIG_DEBUG_FS + struct dentry *xi_dbgaufs; +#endif +}; + +/* members for writable branch only */ +enum {AuBrWh_BASE, AuBrWh_PLINK, AuBrWh_ORPH, AuBrWh_Last}; +struct au_wbr { + struct au_rwsem wbr_wh_rwsem; + struct dentry *wbr_wh[AuBrWh_Last]; + atomic_t wbr_wh_running; +#define wbr_whbase wbr_wh[AuBrWh_BASE] /* whiteout base */ +#define wbr_plink wbr_wh[AuBrWh_PLINK] /* pseudo-link dir */ +#define wbr_orph wbr_wh[AuBrWh_ORPH] /* dir for orphans */ + + /* mfs mode */ + unsigned long long wbr_bytes; +}; + +/* protected by superblock rwsem */ +struct au_branch { + struct au_xino_file br_xino; + + aufs_bindex_t br_id; + + int br_perm; + struct vfsmount *br_mnt; + atomic_t br_count; + + struct au_wbr *br_wbr; + + /* xino truncation */ + blkcnt_t br_xino_upper; /* watermark in blocks */ + atomic_t br_xino_running; + +#ifdef CONFIG_SYSFS + /* an entry under sysfs per mount-point */ + char br_name[8]; + struct attribute br_attr; +#endif +}; + +/* ---------------------------------------------------------------------- */ + +/* branch permission and attribute */ +enum { + AuBrPerm_RW, /* writable, linkable wh */ + AuBrPerm_RO, /* readonly, no wh */ + AuBrPerm_RR, /* natively readonly, no wh */ + + AuBrPerm_RWNoLinkWH, /* un-linkable whiteouts */ + + AuBrPerm_ROWH, /* whiteout-able */ + AuBrPerm_RRWH, /* whiteout-able */ + + AuBrPerm_Last +}; + +static inline int au_br_writable(int brperm) +{ + return brperm == AuBrPerm_RW || brperm == AuBrPerm_RWNoLinkWH; +} + +static inline int au_br_whable(int brperm) +{ + return brperm == AuBrPerm_RW + || brperm == AuBrPerm_ROWH + || brperm == AuBrPerm_RRWH; +} + +static inline int au_br_rdonly(struct au_branch *br) +{ + return ((br->br_mnt->mnt_sb->s_flags & MS_RDONLY) + || !au_br_writable(br->br_perm)) + ? -EROFS : 0; +} + +static inline int au_br_hinotifyable(int brperm __maybe_unused) +{ +#ifdef CONFIG_AUFS_HINOTIFY + return brperm != AuBrPerm_RR && brperm != AuBrPerm_RRWH; +#else + return 0; +#endif +} + +/* ---------------------------------------------------------------------- */ + +/* branch.c */ +struct au_sbinfo; +void au_br_free(struct au_sbinfo *sinfo); +int au_br_index(struct super_block *sb, aufs_bindex_t br_id); +struct au_opt_add; +int au_br_add(struct super_block *sb, struct au_opt_add *add, int remount); +struct au_opt_del; +int au_br_del(struct super_block *sb, struct au_opt_del *del, int remount); +struct au_opt_mod; +int au_br_mod(struct super_block *sb, struct au_opt_mod *mod, int remount, + int *do_update); + +/* xino.c */ +static const loff_t au_loff_max = LLONG_MAX; + +int au_xib_trunc(struct super_block *sb); +ssize_t xino_fread(au_readf_t func, struct file *file, void *buf, size_t size, + loff_t *pos); +ssize_t xino_fwrite(au_writef_t func, struct file *file, void *buf, size_t size, + loff_t *pos); +struct file *au_xino_create2(struct file *base_file, struct file *copy_src); +struct file *au_xino_create(struct super_block *sb, char *fname, int silent); +ino_t au_xino_new_ino(struct super_block *sb); +int au_xino_write0(struct super_block *sb, aufs_bindex_t bindex, ino_t h_ino, + ino_t ino); +int au_xino_write(struct super_block *sb, aufs_bindex_t bindex, ino_t h_ino, + ino_t ino); +int au_xino_read(struct super_block *sb, aufs_bindex_t bindex, ino_t h_ino, + ino_t *ino); +int au_xino_br(struct super_block *sb, struct au_branch *br, ino_t hino, + struct file *base_file, int do_test); +int au_xino_trunc(struct super_block *sb, aufs_bindex_t bindex); + +struct au_opt_xino; +int au_xino_set(struct super_block *sb, struct au_opt_xino *xino, int remount); +void au_xino_clr(struct super_block *sb); +struct file *au_xino_def(struct super_block *sb); +int au_xino_path(struct seq_file *seq, struct file *file); + +/* ---------------------------------------------------------------------- */ + +/* Superblock to branch */ +static inline +aufs_bindex_t au_sbr_id(struct super_block *sb, aufs_bindex_t bindex) +{ + return au_sbr(sb, bindex)->br_id; +} + +static inline +struct vfsmount *au_sbr_mnt(struct super_block *sb, aufs_bindex_t bindex) +{ + return au_sbr(sb, bindex)->br_mnt; +} + +static inline +struct super_block *au_sbr_sb(struct super_block *sb, aufs_bindex_t bindex) +{ + return au_sbr_mnt(sb, bindex)->mnt_sb; +} + +static inline void au_sbr_put(struct super_block *sb, aufs_bindex_t bindex) +{ + atomic_dec_return(&au_sbr(sb, bindex)->br_count); +} + +static inline int au_sbr_perm(struct super_block *sb, aufs_bindex_t bindex) +{ + return au_sbr(sb, bindex)->br_perm; +} + +static inline int au_sbr_whable(struct super_block *sb, aufs_bindex_t bindex) +{ + return au_br_whable(au_sbr_perm(sb, bindex)); +} + +/* ---------------------------------------------------------------------- */ + +/* + * wbr_wh_read_lock, wbr_wh_write_lock + * wbr_wh_read_unlock, wbr_wh_write_unlock, wbr_wh_downgrade_lock + */ +AuSimpleRwsemFuncs(wbr_wh, struct au_wbr *wbr, &wbr->wbr_wh_rwsem); + +#define WbrWhMustNoWaiters(wbr) AuRwMustNoWaiters(&wbr->wbr_wh_rwsem) +#define WbrWhMustAnyLock(wbr) AuRwMustAnyLock(&wbr->wbr_wh_rwsem) +#define WbrWhMustWriteLock(wbr) AuRwMustWriteLock(&wbr->wbr_wh_rwsem) + +#endif /* __KERNEL__ */ +#endif /* __AUFS_BRANCH_H__ */ diff -Nur linux-2.6.31.5.orig/fs/aufs/cpup.c linux-2.6.31.5/fs/aufs/cpup.c --- linux-2.6.31.5.orig/fs/aufs/cpup.c 1970-01-01 01:00:00.000000000 +0100 +++ linux-2.6.31.5/fs/aufs/cpup.c 2009-11-15 22:02:37.000000000 +0100 @@ -0,0 +1,1048 @@ +/* + * Copyright (C) 2005-2009 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, write to the Free Software + * Foundation, Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA + */ + +/* + * copy-up functions, see wbr_policy.c for copy-down + */ + +#include <linux/file.h> +#include <linux/fs_stack.h> +#include <linux/mm.h> +#include <linux/uaccess.h> +#include "aufs.h" + +void au_cpup_attr_flags(struct inode *dst, struct inode *src) +{ + const unsigned int mask = S_DEAD | S_SWAPFILE | S_PRIVATE + | S_NOATIME | S_NOCMTIME; + + dst->i_flags |= src->i_flags & ~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_ibstart(inode)); + fsstack_copy_attr_times(inode, h_inode); + vfsub_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, bend; + + sb = inode->i_sb; + bindex = au_ibstart(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; + + inode->i_nlink = 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)) { + bend = au_ibend(inode); + for (bindex++; bindex <= bend; 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_ibstart(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); +} + +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_ibstart(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 = h_path->dentry->d_inode; + 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; + + err = vfsub_notify_change(&dt->dt_h_path, &attr); + if (unlikely(err)) + AuWarn("restoring timestamps failed(%d). ignored\n", err); +} + +/* ---------------------------------------------------------------------- */ + +static noinline_for_stack +int cpup_iattr(struct dentry *dst, aufs_bindex_t bindex, struct dentry *h_src) +{ + int err, sbits; + struct iattr ia; + struct path h_path; + struct inode *h_isrc, *h_idst; + + h_path.dentry = au_h_dptr(dst, bindex); + h_idst = h_path.dentry->d_inode; + h_path.mnt = au_sbr_mnt(dst->d_sb, bindex); + h_isrc = h_src->d_inode; + ia.ia_valid = ATTR_FORCE | ATTR_UID | ATTR_GID + | ATTR_ATIME | ATTR_MTIME + | ATTR_ATIME_SET | ATTR_MTIME_SET; + 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); + err = vfsub_notify_change(&h_path, &ia); + + /* 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); + } + + 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 mutex *h_mtx; + /* 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; + } + } 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_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_mtx = &dst->f_dentry->d_inode->i_mutex; + mutex_lock_nested(h_mtx, AuLsc_I_CHILD2); + err = vfsub_notify_change(&dst->f_path, ia); + mutex_unlock(h_mtx); + } + } + + 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_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) + kfree(buf); + else + 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 dentry *dentry, aufs_bindex_t bdst, + aufs_bindex_t bsrc, loff_t len) +{ + int err, i; + enum { SRC, DST }; + struct { + aufs_bindex_t bindex; + unsigned int flags; + struct dentry *dentry; + struct file *file; + void *label, *label_file; + } *f, file[] = { + { + .bindex = bsrc, + .flags = O_RDONLY | O_NOATIME | O_LARGEFILE, + .file = NULL, + .label = &&out, + .label_file = &&out_src + }, + { + .bindex = bdst, + .flags = O_WRONLY | O_NOATIME | O_LARGEFILE, + .file = NULL, + .label = &&out_src, + .label_file = &&out_dst + } + }; + struct super_block *sb; + + /* bsrc branch can be ro/rw. */ + sb = dentry->d_sb; + f = file; + for (i = 0; i < 2; i++, f++) { + f->dentry = au_h_dptr(dentry, f->bindex); + f->file = au_h_open(dentry, f->bindex, f->flags, /*file*/NULL); + err = PTR_ERR(f->file); + if (IS_ERR(f->file)) + goto *f->label; + err = -EINVAL; + if (unlikely(!f->file->f_op)) + goto *f->label_file; + } + + /* try stopping to update while we copyup */ + IMustLock(file[SRC].dentry->d_inode); + err = au_copy_file(file[DST].file, file[SRC].file, len); + + out_dst: + fput(file[DST].file); + 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 dentry *dentry, aufs_bindex_t bdst, + aufs_bindex_t bsrc, loff_t len, + struct inode *h_dir, struct path *h_path) +{ + int err, rerr; + loff_t l; + + err = 0; + l = i_size_read(au_h_iptr(dentry->d_inode, bsrc)); + if (len == -1 || l < len) + len = l; + if (len) + err = au_cp_regular(dentry, bdst, bsrc, len); + if (!err) + goto out; /* success */ + + rerr = vfsub_unlink(h_dir, h_path, /*force*/0); + if (rerr) { + AuIOErr("failed unlinking cpup-ed %.*s(%d, %d)\n", + AuDLNPair(h_path->dentry), err, rerr); + err = -EIO; + } + + 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; + char *sym; + + err = -ENOSYS; + if (unlikely(!h_src->d_inode->i_op->readlink)) + goto out; + + err = -ENOMEM; + sym = __getname(); + if (unlikely(!sym)) + goto out; + + old_fs = get_fs(); + set_fs(KERNEL_DS); + symlen = h_src->d_inode->i_op->readlink(h_src, (char __user *)sym, + PATH_MAX); + err = symlen; + set_fs(old_fs); + + if (symlen > 0) { + sym[symlen] = 0; + err = vfsub_symlink(h_dir, h_path, sym); + } + __putname(sym); + + out: + return err; +} + +/* return with the lower dst inode is locked */ +static noinline_for_stack +int cpup_entry(struct dentry *dentry, aufs_bindex_t bdst, + aufs_bindex_t bsrc, loff_t len, unsigned int flags, + struct dentry *dst_parent) +{ + int err; + umode_t mode; + unsigned int mnt_flags; + unsigned char isdir; + const unsigned char do_dt = !!au_ftest_cpup(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(dentry, bsrc); + h_inode = h_src->d_inode; + AuDebugOn(h_inode != au_h_iptr(dentry->d_inode, bsrc)); + + /* try stopping to be referenced while we are creating */ + h_dst = au_h_dptr(dentry, bdst); + h_parent = h_dst->d_parent; /* dir inode is locked */ + h_dir = h_parent->d_inode; + IMustLock(h_dir); + AuDebugOn(h_parent != h_dst->d_parent); + + sb = dentry->d_sb; + h_path.mnt = au_sbr_mnt(sb, bdst); + if (do_dt) { + h_path.dentry = h_parent; + au_dtime_store(&dt, dst_parent, &h_path); + } + h_path.dentry = h_dst; + + isdir = 0; + mode = h_inode->i_mode; + switch (mode & S_IFMT) { + case S_IFREG: + /* try stopping to update while we are referencing */ + IMustLock(h_inode); + err = vfsub_create(h_dir, &h_path, mode | S_IWUSR); + if (!err) + err = au_do_cpup_regular + (dentry, bdst, bsrc, len, + au_h_iptr(dst_parent->d_inode, bdst), &h_path); + break; + case S_IFDIR: + isdir = 1; + err = vfsub_mkdir(h_dir, &h_path, mode); + if (!err) { + /* + * strange behaviour from the users view, + * particularry setattr case + */ + if (au_ibstart(dst_parent->d_inode) == bdst) + au_cpup_attr_nlink(dst_parent->d_inode, + /*force*/1); + au_cpup_attr_nlink(dentry->d_inode, /*force*/1); + } + 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; + } + + 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 + /* todo: unnecessary? */ + /* && dentry->d_inode->i_nlink == 1 */ + && bdst < bsrc + && !au_ftest_cpup(flags, KEEPLINO)) + au_xino_write(sb, bsrc, h_inode->i_ino, /*ino*/0); + /* ignore this error */ + + if (do_dt) + au_dtime_revert(&dt); + 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. + */ +static int au_cpup_single(struct dentry *dentry, aufs_bindex_t bdst, + aufs_bindex_t bsrc, loff_t len, unsigned int flags, + struct dentry *dst_parent) +{ + int err, rerr; + aufs_bindex_t old_ibstart; + unsigned char isdir, plink; + struct au_dtime dt; + struct path h_path; + struct dentry *h_src, *h_dst, *h_parent; + struct inode *dst_inode, *h_dir, *inode; + struct super_block *sb; + + AuDebugOn(bsrc <= bdst); + + sb = dentry->d_sb; + h_path.mnt = au_sbr_mnt(sb, bdst); + h_dst = au_h_dptr(dentry, bdst); + h_parent = h_dst->d_parent; /* dir inode is locked */ + h_dir = h_parent->d_inode; + IMustLock(h_dir); + + h_src = au_h_dptr(dentry, bsrc); + inode = dentry->d_inode; + + if (!dst_parent) + dst_parent = dget_parent(dentry); + else + dget(dst_parent); + + plink = !!au_opt_test(au_mntflags(sb), PLINK); + dst_inode = au_h_iptr(inode, bdst); + if (dst_inode) { + if (unlikely(!plink)) { + err = -EIO; + AuIOErr("i%lu exists on a upper branch " + "but plink is disabled\n", inode->i_ino); + goto out; + } + + if (dst_inode->i_nlink) { + const int do_dt = au_ftest_cpup(flags, DTIME); + + h_src = au_plink_lkup(inode, bdst); + err = PTR_ERR(h_src); + if (IS_ERR(h_src)) + goto out; + if (unlikely(!h_src->d_inode)) { + err = -EIO; + AuIOErr("i%lu exists on a upper branch " + "but plink is broken\n", inode->i_ino); + dput(h_src); + goto out; + } + + if (do_dt) { + h_path.dentry = h_parent; + au_dtime_store(&dt, dst_parent, &h_path); + } + h_path.dentry = h_dst; + err = vfsub_link(h_src, h_dir, &h_path); + if (do_dt) + au_dtime_revert(&dt); + dput(h_src); + goto out; + } else + /* todo: cpup_wh_file? */ + /* udba work */ + au_update_brange(inode, 1); + } + + old_ibstart = au_ibstart(inode); + err = cpup_entry(dentry, bdst, bsrc, len, flags, dst_parent); + if (unlikely(err)) + goto out; + dst_inode = h_dst->d_inode; + mutex_lock_nested(&dst_inode->i_mutex, AuLsc_I_CHILD2); + + err = cpup_iattr(dentry, bdst, h_src); + isdir = S_ISDIR(dst_inode->i_mode); + if (!err) { + if (bdst < old_ibstart) + au_set_ibstart(inode, bdst); + au_set_h_iptr(inode, bdst, au_igrab(dst_inode), + au_hi_flags(inode, isdir)); + mutex_unlock(&dst_inode->i_mutex); + if (!isdir + && h_src->d_inode->i_nlink > 1 + && plink) + au_plink_append(inode, bdst, h_dst); + goto out; /* success */ + } + + /* revert */ + h_path.dentry = h_parent; + mutex_unlock(&dst_inode->i_mutex); + au_dtime_store(&dt, dst_parent, &h_path); + h_path.dentry = h_dst; + if (!isdir) + rerr = vfsub_unlink(h_dir, &h_path, /*force*/0); + else + rerr = vfsub_rmdir(h_dir, &h_path); + au_dtime_revert(&dt); + if (rerr) { + AuIOErr("failed removing broken entry(%d, %d)\n", err, rerr); + err = -EIO; + } + + out: + dput(dst_parent); + return err; +} + +struct au_cpup_single_args { + int *errp; + struct dentry *dentry; + aufs_bindex_t bdst, bsrc; + loff_t len; + unsigned int flags; + struct dentry *dst_parent; +}; + +static void au_call_cpup_single(void *args) +{ + struct au_cpup_single_args *a = args; + *a->errp = au_cpup_single(a->dentry, a->bdst, a->bsrc, a->len, + a->flags, a->dst_parent); +} + +int au_sio_cpup_single(struct dentry *dentry, aufs_bindex_t bdst, + aufs_bindex_t bsrc, loff_t len, unsigned int flags, + struct dentry *dst_parent) +{ + int err, wkq_err; + umode_t mode; + struct dentry *h_dentry; + + h_dentry = au_h_dptr(dentry, bsrc); + mode = h_dentry->d_inode->i_mode & S_IFMT; + if ((mode != S_IFCHR && mode != S_IFBLK) + || capable(CAP_MKNOD)) + err = au_cpup_single(dentry, bdst, bsrc, len, flags, + dst_parent); + else { + struct au_cpup_single_args args = { + .errp = &err, + .dentry = dentry, + .bdst = bdst, + .bsrc = bsrc, + .len = len, + .flags = flags, + .dst_parent = dst_parent + }; + wkq_err = au_wkq_wait(au_call_cpup_single, &args); + if (unlikely(wkq_err)) + err = wkq_err; + } + + return err; +} + +/* + * copyup the @dentry from the first active lower branch to @bdst, + * using au_cpup_single(). + */ +static int au_cpup_simple(struct dentry *dentry, aufs_bindex_t bdst, loff_t len, + unsigned int flags) +{ + int err; + aufs_bindex_t bsrc, bend; + + bend = au_dbend(dentry); + for (bsrc = bdst + 1; bsrc <= bend; bsrc++) + if (au_h_dptr(dentry, bsrc)) + break; + + err = au_lkup_neg(dentry, bdst); + if (!err) { + err = au_cpup_single(dentry, bdst, bsrc, len, flags, NULL); + if (!err) + return 0; /* success */ + + /* revert */ + au_set_h_dptr(dentry, bdst, NULL); + au_set_dbstart(dentry, bsrc); + } + + return err; +} + +struct au_cpup_simple_args { + int *errp; + struct dentry *dentry; + aufs_bindex_t bdst; + loff_t len; + unsigned int flags; +}; + +static void au_call_cpup_simple(void *args) +{ + struct au_cpup_simple_args *a = args; + *a->errp = au_cpup_simple(a->dentry, a->bdst, a->len, a->flags); +} + +int au_sio_cpup_simple(struct dentry *dentry, aufs_bindex_t bdst, loff_t len, + unsigned int flags) +{ + int err, wkq_err; + unsigned char do_sio; + struct dentry *parent; + struct inode *h_dir; + + parent = dget_parent(dentry); + h_dir = au_h_iptr(parent->d_inode, bdst); + do_sio = !!au_test_h_perm_sio(h_dir, MAY_EXEC | MAY_WRITE); + if (!do_sio) { + /* + * testing CAP_MKNOD is for generic fs, + * but CAP_FSETID is for xfs only, currently. + */ + umode_t mode = dentry->d_inode->i_mode; + do_sio = (((mode & (S_IFCHR | S_IFBLK)) + && !capable(CAP_MKNOD)) + || ((mode & (S_ISUID | S_ISGID)) + && !capable(CAP_FSETID))); + } + if (!do_sio) + err = au_cpup_simple(dentry, bdst, len, flags); + else { + struct au_cpup_simple_args args = { + .errp = &err, + .dentry = dentry, + .bdst = bdst, + .len = len, + .flags = flags + }; + wkq_err = au_wkq_wait(au_call_cpup_simple, &args); + if (unlikely(wkq_err)) + err = wkq_err; + } + + dput(parent); + return err; +} + +/* ---------------------------------------------------------------------- */ + +/* + * copyup the deleted file for writing. + */ +static int au_do_cpup_wh(struct dentry *dentry, aufs_bindex_t bdst, + struct dentry *wh_dentry, struct file *file, + loff_t len) +{ + int err; + aufs_bindex_t bstart; + struct au_dinfo *dinfo; + struct dentry *h_d_dst, *h_d_start; + + dinfo = au_di(dentry); + AuRwMustWriteLock(&dinfo->di_rwsem); + + bstart = dinfo->di_bstart; + h_d_dst = dinfo->di_hdentry[0 + bdst].hd_dentry; + dinfo->di_bstart = bdst; + dinfo->di_hdentry[0 + bdst].hd_dentry = wh_dentry; + h_d_start = dinfo->di_hdentry[0 + bstart].hd_dentry; + if (file) + dinfo->di_hdentry[0 + bstart].hd_dentry + = au_h_fptr(file, au_fbstart(file))->f_dentry; + err = au_cpup_single(dentry, bdst, bstart, len, !AuCpup_DTIME, + /*h_parent*/NULL); + if (!err && file) { + err = au_reopen_nondir(file); + dinfo->di_hdentry[0 + bstart].hd_dentry = h_d_start; + } + dinfo->di_hdentry[0 + bdst].hd_dentry = h_d_dst; + dinfo->di_bstart = bstart; + + return err; +} + +static int au_cpup_wh(struct dentry *dentry, aufs_bindex_t bdst, loff_t len, + struct file *file) +{ + int err; + struct au_dtime dt; + struct dentry *parent, *h_parent, *wh_dentry; + struct au_branch *br; + struct path h_path; + + 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 = br->br_mnt; + au_dtime_store(&dt, parent, &h_path); + err = au_do_cpup_wh(dentry, bdst, wh_dentry, file, len); + if (unlikely(err)) + goto out_wh; + + dget(wh_dentry); + h_path.dentry = wh_dentry; + err = vfsub_unlink(h_parent->d_inode, &h_path, /*force*/0); + if (unlikely(err)) { + AuIOErr("failed remove copied-up tmp file %.*s(%d)\n", + AuDLNPair(wh_dentry), err); + err = -EIO; + } + au_dtime_revert(&dt); + au_set_hi_wh(dentry->d_inode, bdst, wh_dentry); + + out_wh: + dput(wh_dentry); + out: + dput(parent); + return err; +} + +struct au_cpup_wh_args { + int *errp; + struct dentry *dentry; + aufs_bindex_t bdst; + loff_t len; + struct file *file; +}; + +static void au_call_cpup_wh(void *args) +{ + struct au_cpup_wh_args *a = args; + *a->errp = au_cpup_wh(a->dentry, a->bdst, a->len, a->file); +} + +int au_sio_cpup_wh(struct dentry *dentry, aufs_bindex_t bdst, loff_t len, + struct file *file) +{ + int err, wkq_err; + struct dentry *parent, *h_orph, *h_parent, *h_dentry; + struct inode *dir, *h_dir, *h_tmpdir, *h_inode; + struct au_wbr *wbr; + + parent = dget_parent(dentry); + dir = parent->d_inode; + h_orph = NULL; + h_parent = NULL; + h_dir = au_igrab(au_h_iptr(dir, bdst)); + h_tmpdir = h_dir; + 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, NULL); + au_set_h_dptr(parent, bdst, dget(h_orph)); + h_tmpdir = h_orph->d_inode; + au_set_h_iptr(dir, bdst, NULL, 0); + au_set_h_iptr(dir, bdst, au_igrab(h_tmpdir), /*flags*/0); + + /* this temporary unlock is safe */ + if (file) + h_dentry = au_h_fptr(file, au_fbstart(file))->f_dentry; + else + h_dentry = au_h_dptr(dentry, au_dbstart(dentry)); + h_inode = h_dentry->d_inode; + IMustLock(h_inode); + mutex_unlock(&h_inode->i_mutex); + mutex_lock_nested(&h_tmpdir->i_mutex, AuLsc_I_PARENT3); + mutex_lock_nested(&h_inode->i_mutex, AuLsc_I_CHILD); + } + + if (!au_test_h_perm_sio(h_tmpdir, MAY_EXEC | MAY_WRITE)) + err = au_cpup_wh(dentry, bdst, len, file); + else { + struct au_cpup_wh_args args = { + .errp = &err, + .dentry = dentry, + .bdst = bdst, + .len = len, + .file = file + }; + wkq_err = au_wkq_wait(au_call_cpup_wh, &args); + if (unlikely(wkq_err)) + err = wkq_err; + } + + if (h_orph) { + mutex_unlock(&h_tmpdir->i_mutex); + au_set_h_iptr(dir, bdst, NULL, 0); + au_set_h_iptr(dir, bdst, au_igrab(h_dir), /*flags*/0); + au_set_h_dptr(parent, bdst, NULL); + au_set_h_dptr(parent, bdst, h_parent); + } + 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 dentry *h_parent, void *arg), + void *arg) +{ + int err; + struct au_pin pin; + struct dentry *d, *parent, *h_parent, *real_parent; + + 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 */ + if (!au_h_dptr(d, bdst) || !au_h_dptr(d, bdst)->d_inode) { + if (au_h_dptr(d, bdst)) + au_update_dbstart(d); + + au_pin_set_dentry(&pin, d); + err = au_do_pin(&pin); + if (!err) { + err = cp(d, bdst, 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 dentry *h_parent __maybe_unused , + void *arg __maybe_unused) +{ + return au_sio_cpup_simple(dentry, bdst, -1, AuCpup_DTIME); +} + +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 = parent->d_inode; + 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; +} diff -Nur linux-2.6.31.5.orig/fs/aufs/cpup.h linux-2.6.31.5/fs/aufs/cpup.h --- linux-2.6.31.5.orig/fs/aufs/cpup.h 1970-01-01 01:00:00.000000000 +0100 +++ linux-2.6.31.5/fs/aufs/cpup.h 2009-11-15 22:02:37.000000000 +0100 @@ -0,0 +1,81 @@ +/* + * Copyright (C) 2005-2009 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, write to the Free Software + * Foundation, Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA + */ + +/* + * copy-up/down functions + */ + +#ifndef __AUFS_CPUP_H__ +#define __AUFS_CPUP_H__ + +#ifdef __KERNEL__ + +#include <linux/path.h> +#include <linux/time.h> +#include <linux/aufs_type.h> + +struct inode; +struct file; + +void au_cpup_attr_flags(struct inode *dst, struct inode *src); +void au_cpup_attr_timesizes(struct inode *inode); +void au_cpup_attr_nlink(struct inode *inode, int force); +void au_cpup_attr_changeable(struct inode *inode); +void au_cpup_igen(struct inode *inode, struct inode *h_inode); +void au_cpup_attr_all(struct inode *inode, int force); + +/* ---------------------------------------------------------------------- */ + +/* cpup flags */ +#define AuCpup_DTIME 1 /* do dtime_store/revert */ +#define AuCpup_KEEPLINO (1 << 1) /* do not clear the lower xino, + for link(2) */ +#define au_ftest_cpup(flags, name) ((flags) & AuCpup_##name) +#define au_fset_cpup(flags, name) { (flags) |= AuCpup_##name; } +#define au_fclr_cpup(flags, name) { (flags) &= ~AuCpup_##name; } + +int au_copy_file(struct file *dst, struct file *src, loff_t len); +int au_sio_cpup_single(struct dentry *dentry, aufs_bindex_t bdst, + aufs_bindex_t bsrc, loff_t len, unsigned int flags, + struct dentry *dst_parent); +int au_sio_cpup_simple(struct dentry *dentry, aufs_bindex_t bdst, loff_t len, + unsigned int flags); +int au_sio_cpup_wh(struct dentry *dentry, aufs_bindex_t bdst, loff_t len, + struct file *file); + +int au_cp_dirs(struct dentry *dentry, aufs_bindex_t bdst, + int (*cp)(struct dentry *dentry, aufs_bindex_t bdst, + struct dentry *h_parent, void *arg), + void *arg); +int au_cpup_dirs(struct dentry *dentry, aufs_bindex_t bdst); +int au_test_and_cpup_dirs(struct dentry *dentry, aufs_bindex_t bdst); + +/* ---------------------------------------------------------------------- */ + +/* keep timestamps when copyup */ +struct au_dtime { + struct dentry *dt_dentry; + struct path dt_h_path; + struct timespec dt_atime, dt_mtime; +}; +void au_dtime_store(struct au_dtime *dt, struct dentry *dentry, + struct path *h_path); +void au_dtime_revert(struct au_dtime *dt); + +#endif /* __KERNEL__ */ +#endif /* __AUFS_CPUP_H__ */ diff -Nur linux-2.6.31.5.orig/fs/aufs/dbgaufs.c linux-2.6.31.5/fs/aufs/dbgaufs.c --- linux-2.6.31.5.orig/fs/aufs/dbgaufs.c 1970-01-01 01:00:00.000000000 +0100 +++ linux-2.6.31.5/fs/aufs/dbgaufs.c 2009-11-15 22:02:37.000000000 +0100 @@ -0,0 +1,331 @@ +/* + * Copyright (C) 2005-2009 Junjiro R. Oka