Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S939009AbZDJHdP (ORCPT ); Fri, 10 Apr 2009 03:33:15 -0400 Received: (majordomo@vger.kernel.org) by vger.kernel.org id S938406AbZDJHXm (ORCPT ); Fri, 10 Apr 2009 03:23:42 -0400 Received: from mfbichi11.ns.itscom.net ([219.110.2.189]:62081 "EHLO mfbichi11.ns.itscom.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S938393AbZDJHXi (ORCPT ); Fri, 10 Apr 2009 03:23:38 -0400 From: "J. R. Okajima" To: linux-kernel@vger.kernel.org Cc: greg@kroah.com, linux-fsdevel@vger.kernel.org, "J. R. Okajima" Subject: [RFC Aufs2 #5 11/29] aufs copy-up Date: Fri, 10 Apr 2009 16:02:25 +0900 Message-Id: <1239346963-30953-12-git-send-email-hooanon05@yahoo.co.jp> X-Mailer: git-send-email 1.6.1.284.g5dc13 In-Reply-To: <1239346963-30953-1-git-send-email-hooanon05@yahoo.co.jp> References: <1239346963-30953-1-git-send-email-hooanon05@yahoo.co.jp> Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 28740 Lines: 1123 initial commit internal copy-up functions see wbr_policy.c for copy-down Signed-off-by: J. R. Okajima --- fs/aufs/cpup.c | 1023 ++++++++++++++++++++++++++++++++++++++++++++++++++++++++ fs/aufs/cpup.h | 68 ++++ 2 files changed, 1091 insertions(+), 0 deletions(-) create mode 100644 fs/aufs/cpup.c create mode 100644 fs/aufs/cpup.h diff --git a/fs/aufs/cpup.c b/fs/aufs/cpup.c new file mode 100644 index 0000000..900a648 --- /dev/null +++ b/fs/aufs/cpup.c @@ -0,0 +1,1023 @@ +/* + * 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. + */ + +/* + * copy-up functions, see wbr_policy.c for copy-down + */ + +#include +#include +#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); + + 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_path.dentry = au_h_dptr(dst, bindex); + h_path.mnt = au_sbr_mnt(dst->d_sb, bindex); + h_isrc = h_src->d_inode; + ia.ia_valid = ATTR_FORCE | ATTR_MODE | ATTR_UID | ATTR_GID + | ATTR_ATIME | ATTR_MTIME + | ATTR_ATIME_SET | ATTR_MTIME_SET; + ia.ia_mode = h_isrc->i_mode; + 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; + sbits = !!(ia.ia_mode & (S_ISUID | S_ISGID)); + au_cpup_attr_flags(h_path.dentry->d_inode, 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; + } *f, file[] = { + { + .bindex = bsrc, + .flags = O_RDONLY | O_NOATIME | O_LARGEFILE, + .file = NULL, + .label = &&out, + }, + { + .bindex = bdst, + .flags = O_WRONLY | O_NOATIME | O_LARGEFILE, + .file = NULL, + .label = &&out_src, + } + }; + 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; + } + + /* try stopping to update while we copyup */ + IMustLock(file[SRC].dentry->d_inode); + err = au_copy_file(file[DST].file, file[SRC].file, len); + + 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_write0(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); + 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_PARENT2); + 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 --git a/fs/aufs/cpup.h b/fs/aufs/cpup.h new file mode 100644 index 0000000..240014a --- /dev/null +++ b/fs/aufs/cpup.h @@ -0,0 +1,68 @@ +/* + * 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. + */ + +/* + * copy-up/down functions + */ + +#ifndef __AUFS_CPUP_H__ +#define __AUFS_CPUP_H__ + +#ifdef __KERNEL__ + +#include +#include + +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__ */ -- 1.6.1.284.g5dc13 -- To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/