From a700f2d8e79ff80041078f160fe1edccf89b0c66 Mon Sep 17 00:00:00 2001 From: =?UTF-8?q?Andr=C3=A9=20Fabian=20Silva=20Delgado?= Date: Wed, 23 Sep 2015 12:33:14 -0300 Subject: Linux-libre 4.2.1-gnu --- fs/aufs/xino.c | 1297 ++++++++++++++++++++++++++++++++++++++++++++++++++++++++ 1 file changed, 1297 insertions(+) create mode 100644 fs/aufs/xino.c (limited to 'fs/aufs/xino.c') diff --git a/fs/aufs/xino.c b/fs/aufs/xino.c new file mode 100644 index 000000000..053594410 --- /dev/null +++ b/fs/aufs/xino.c @@ -0,0 +1,1297 @@ +/* + * Copyright (C) 2005-2015 Junjiro R. Okajima + * + * This program, aufs is free software; you can redistribute it and/or modify + * it under the terms of the GNU General Public License as published by + * the Free Software Foundation; either version 2 of the License, or + * (at your option) any later version. + * + * This program is distributed in the hope that it will be useful, + * but WITHOUT ANY WARRANTY; without even the implied warranty of + * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the + * GNU General Public License for more details. + * + * You should have received a copy of the GNU General Public License + * along with this program. If not, see . + */ + +/* + * external inode number translation table and bitmap + */ + +#include +#include +#include "aufs.h" + +/* todo: unnecessary to support mmap_sem since kernel-space? */ +ssize_t xino_fread(vfs_readf_t func, struct file *file, void *kbuf, size_t size, + loff_t *pos) +{ + ssize_t err; + mm_segment_t oldfs; + union { + void *k; + char __user *u; + } buf; + + buf.k = kbuf; + oldfs = get_fs(); + set_fs(KERNEL_DS); + do { + /* todo: signal_pending? */ + err = func(file, buf.u, size, pos); + } while (err == -EAGAIN || err == -EINTR); + set_fs(oldfs); + +#if 0 /* reserved for future use */ + if (err > 0) + fsnotify_access(file->f_path.dentry); +#endif + + return err; +} + +/* ---------------------------------------------------------------------- */ + +static ssize_t do_xino_fwrite(vfs_writef_t func, struct file *file, void *kbuf, + size_t size, loff_t *pos) +{ + ssize_t err; + mm_segment_t oldfs; + union { + void *k; + const char __user *u; + } buf; + + buf.k = kbuf; + oldfs = get_fs(); + set_fs(KERNEL_DS); + do { + /* todo: signal_pending? */ + err = func(file, buf.u, size, pos); + } while (err == -EAGAIN || err == -EINTR); + set_fs(oldfs); + +#if 0 /* reserved for future use */ + if (err > 0) + fsnotify_modify(file->f_path.dentry); +#endif + + return err; +} + +struct do_xino_fwrite_args { + ssize_t *errp; + vfs_writef_t func; + struct file *file; + void *buf; + size_t size; + loff_t *pos; +}; + +static void call_do_xino_fwrite(void *args) +{ + struct do_xino_fwrite_args *a = args; + *a->errp = do_xino_fwrite(a->func, a->file, a->buf, a->size, a->pos); +} + +ssize_t xino_fwrite(vfs_writef_t func, struct file *file, void *buf, + size_t size, loff_t *pos) +{ + ssize_t err; + + /* todo: signal block and no wkq? */ + if (rlimit(RLIMIT_FSIZE) == RLIM_INFINITY) { + lockdep_off(); + err = do_xino_fwrite(func, file, buf, size, pos); + lockdep_on(); + } else { + /* + * it breaks RLIMIT_FSIZE and normal user's limit, + * users should care about quota and real 'filesystem full.' + */ + int wkq_err; + struct do_xino_fwrite_args args = { + .errp = &err, + .func = func, + .file = file, + .buf = buf, + .size = size, + .pos = pos + }; + + wkq_err = au_wkq_wait(call_do_xino_fwrite, &args); + if (unlikely(wkq_err)) + err = wkq_err; + } + + return err; +} + +/* ---------------------------------------------------------------------- */ + +/* + * create a new xinofile at the same place/path as @base_file. + */ +struct file *au_xino_create2(struct file *base_file, struct file *copy_src) +{ + struct file *file; + struct dentry *base, *parent; + struct inode *dir, *delegated; + struct qstr *name; + struct path path; + int err; + + base = base_file->f_path.dentry; + parent = base->d_parent; /* dir inode is locked */ + dir = d_inode(parent); + IMustLock(dir); + + file = ERR_PTR(-EINVAL); + name = &base->d_name; + path.dentry = vfsub_lookup_one_len(name->name, parent, name->len); + if (IS_ERR(path.dentry)) { + file = (void *)path.dentry; + pr_err("%pd lookup err %ld\n", + base, PTR_ERR(path.dentry)); + goto out; + } + + /* no need to mnt_want_write() since we call dentry_open() later */ + err = vfs_create(dir, path.dentry, S_IRUGO | S_IWUGO, NULL); + if (unlikely(err)) { + file = ERR_PTR(err); + pr_err("%pd create err %d\n", base, err); + goto out_dput; + } + + path.mnt = base_file->f_path.mnt; + file = vfsub_dentry_open(&path, + O_RDWR | O_CREAT | O_EXCL | O_LARGEFILE + /* | __FMODE_NONOTIFY */); + if (IS_ERR(file)) { + pr_err("%pd open err %ld\n", base, PTR_ERR(file)); + goto out_dput; + } + + delegated = NULL; + err = vfsub_unlink(dir, &file->f_path, &delegated, /*force*/0); + if (unlikely(err == -EWOULDBLOCK)) { + pr_warn("cannot retry for NFSv4 delegation" + " for an internal unlink\n"); + iput(delegated); + } + if (unlikely(err)) { + pr_err("%pd unlink err %d\n", base, err); + goto out_fput; + } + + if (copy_src) { + /* no one can touch copy_src xino */ + err = au_copy_file(file, copy_src, vfsub_f_size_read(copy_src)); + if (unlikely(err)) { + pr_err("%pd copy err %d\n", base, err); + goto out_fput; + } + } + goto out_dput; /* success */ + +out_fput: + fput(file); + file = ERR_PTR(err); +out_dput: + dput(path.dentry); +out: + return file; +} + +struct au_xino_lock_dir { + struct au_hinode *hdir; + struct dentry *parent; + struct mutex *mtx; +}; + +static void au_xino_lock_dir(struct super_block *sb, struct file *xino, + struct au_xino_lock_dir *ldir) +{ + aufs_bindex_t brid, bindex; + + ldir->hdir = NULL; + bindex = -1; + brid = au_xino_brid(sb); + if (brid >= 0) + bindex = au_br_index(sb, brid); + if (bindex >= 0) { + ldir->hdir = au_hi(d_inode(sb->s_root), bindex); + au_hn_imtx_lock_nested(ldir->hdir, AuLsc_I_PARENT); + } else { + ldir->parent = dget_parent(xino->f_path.dentry); + ldir->mtx = &d_inode(ldir->parent)->i_mutex; + mutex_lock_nested(ldir->mtx, AuLsc_I_PARENT); + } +} + +static void au_xino_unlock_dir(struct au_xino_lock_dir *ldir) +{ + if (ldir->hdir) + au_hn_imtx_unlock(ldir->hdir); + else { + mutex_unlock(ldir->mtx); + dput(ldir->parent); + } +} + +/* ---------------------------------------------------------------------- */ + +/* trucate xino files asynchronously */ + +int au_xino_trunc(struct super_block *sb, aufs_bindex_t bindex) +{ + int err; + unsigned long jiffy; + blkcnt_t blocks; + aufs_bindex_t bi, bend; + struct kstatfs *st; + struct au_branch *br; + struct file *new_xino, *file; + struct super_block *h_sb; + struct au_xino_lock_dir ldir; + + err = -ENOMEM; + st = kzalloc(sizeof(*st), GFP_NOFS); + if (unlikely(!st)) + goto out; + + err = -EINVAL; + bend = au_sbend(sb); + if (unlikely(bindex < 0 || bend < bindex)) + goto out_st; + br = au_sbr(sb, bindex); + file = br->br_xino.xi_file; + if (!file) + goto out_st; + + err = vfs_statfs(&file->f_path, st); + if (unlikely(err)) + AuErr1("statfs err %d, ignored\n", err); + jiffy = jiffies; + blocks = file_inode(file)->i_blocks; + pr_info("begin truncating xino(b%d), ib%llu, %llu/%llu free blks\n", + bindex, (u64)blocks, st->f_bfree, st->f_blocks); + + au_xino_lock_dir(sb, file, &ldir); + /* mnt_want_write() is unnecessary here */ + new_xino = au_xino_create2(file, file); + au_xino_unlock_dir(&ldir); + err = PTR_ERR(new_xino); + if (IS_ERR(new_xino)) { + pr_err("err %d, ignored\n", err); + goto out_st; + } + err = 0; + fput(file); + br->br_xino.xi_file = new_xino; + + h_sb = au_br_sb(br); + for (bi = 0; bi <= bend; bi++) { + if (unlikely(bi == bindex)) + continue; + br = au_sbr(sb, bi); + if (au_br_sb(br) != h_sb) + continue; + + fput(br->br_xino.xi_file); + br->br_xino.xi_file = new_xino; + get_file(new_xino); + } + + err = vfs_statfs(&new_xino->f_path, st); + if (!err) { + pr_info("end truncating xino(b%d), ib%llu, %llu/%llu free blks\n", + bindex, (u64)file_inode(new_xino)->i_blocks, + st->f_bfree, st->f_blocks); + if (file_inode(new_xino)->i_blocks < blocks) + au_sbi(sb)->si_xino_jiffy = jiffy; + } else + AuErr1("statfs err %d, ignored\n", err); + +out_st: + kfree(st); +out: + return err; +} + +struct xino_do_trunc_args { + struct super_block *sb; + struct au_branch *br; +}; + +static void xino_do_trunc(void *_args) +{ + struct xino_do_trunc_args *args = _args; + struct super_block *sb; + struct au_branch *br; + struct inode *dir; + int err; + aufs_bindex_t bindex; + + err = 0; + sb = args->sb; + dir = d_inode(sb->s_root); + br = args->br; + + si_noflush_write_lock(sb); + ii_read_lock_parent(dir); + bindex = au_br_index(sb, br->br_id); + err = au_xino_trunc(sb, bindex); + ii_read_unlock(dir); + if (unlikely(err)) + pr_warn("err b%d, (%d)\n", bindex, err); + atomic_dec(&br->br_xino_running); + atomic_dec(&br->br_count); + si_write_unlock(sb); + au_nwt_done(&au_sbi(sb)->si_nowait); + kfree(args); +} + +static int xino_trunc_test(struct super_block *sb, struct au_branch *br) +{ + int err; + struct kstatfs st; + struct au_sbinfo *sbinfo; + + /* todo: si_xino_expire and the ratio should be customizable */ + sbinfo = au_sbi(sb); + if (time_before(jiffies, + sbinfo->si_xino_jiffy + sbinfo->si_xino_expire)) + return 0; + + /* truncation border */ + err = vfs_statfs(&br->br_xino.xi_file->f_path, &st); + if (unlikely(err)) { + AuErr1("statfs err %d, ignored\n", err); + return 0; + } + if (div64_u64(st.f_bfree * 100, st.f_blocks) >= AUFS_XINO_DEF_TRUNC) + return 0; + + return 1; +} + +static void xino_try_trunc(struct super_block *sb, struct au_branch *br) +{ + struct xino_do_trunc_args *args; + int wkq_err; + + if (!xino_trunc_test(sb, br)) + return; + + if (atomic_inc_return(&br->br_xino_running) > 1) + goto out; + + /* lock and kfree() will be called in trunc_xino() */ + args = kmalloc(sizeof(*args), GFP_NOFS); + if (unlikely(!args)) { + AuErr1("no memory\n"); + goto out_args; + } + + atomic_inc(&br->br_count); + args->sb = sb; + args->br = br; + wkq_err = au_wkq_nowait(xino_do_trunc, args, sb, /*flags*/0); + if (!wkq_err) + return; /* success */ + + pr_err("wkq %d\n", wkq_err); + atomic_dec(&br->br_count); + +out_args: + kfree(args); +out: + atomic_dec(&br->br_xino_running); +} + +/* ---------------------------------------------------------------------- */ + +static int au_xino_do_write(vfs_writef_t write, struct file *file, + ino_t h_ino, ino_t ino) +{ + loff_t pos; + ssize_t sz; + + pos = h_ino; + if (unlikely(au_loff_max / sizeof(ino) - 1 < pos)) { + AuIOErr1("too large hi%lu\n", (unsigned long)h_ino); + return -EFBIG; + } + pos *= sizeof(ino); + sz = xino_fwrite(write, file, &ino, sizeof(ino), &pos); + if (sz == sizeof(ino)) + return 0; /* success */ + + AuIOErr("write failed (%zd)\n", sz); + return -EIO; +} + +/* + * write @ino to the xinofile for the specified branch{@sb, @bindex} + * at the position of @h_ino. + * even if @ino is zero, it is written to the xinofile and means no entry. + * if the size of the xino file on a specific filesystem exceeds the watermark, + * try truncating it. + */ +int au_xino_write(struct super_block *sb, aufs_bindex_t bindex, ino_t h_ino, + ino_t ino) +{ + int err; + unsigned int mnt_flags; + struct au_branch *br; + + BUILD_BUG_ON(sizeof(long long) != sizeof(au_loff_max) + || ((loff_t)-1) > 0); + SiMustAnyLock(sb); + + mnt_flags = au_mntflags(sb); + if (!au_opt_test(mnt_flags, XINO)) + return 0; + + br = au_sbr(sb, bindex); + err = au_xino_do_write(au_sbi(sb)->si_xwrite, br->br_xino.xi_file, + h_ino, ino); + if (!err) { + if (au_opt_test(mnt_flags, TRUNC_XINO) + && au_test_fs_trunc_xino(au_br_sb(br))) + xino_try_trunc(sb, br); + return 0; /* success */ + } + + AuIOErr("write failed (%d)\n", err); + return -EIO; +} + +/* ---------------------------------------------------------------------- */ + +/* aufs inode number bitmap */ + +static const int page_bits = (int)PAGE_SIZE * BITS_PER_BYTE; +static ino_t xib_calc_ino(unsigned long pindex, int bit) +{ + ino_t ino; + + AuDebugOn(bit < 0 || page_bits <= bit); + ino = AUFS_FIRST_INO + pindex * page_bits + bit; + return ino; +} + +static void xib_calc_bit(ino_t ino, unsigned long *pindex, int *bit) +{ + AuDebugOn(ino < AUFS_FIRST_INO); + ino -= AUFS_FIRST_INO; + *pindex = ino / page_bits; + *bit = ino % page_bits; +} + +static int xib_pindex(struct super_block *sb, unsigned long pindex) +{ + int err; + loff_t pos; + ssize_t sz; + struct au_sbinfo *sbinfo; + struct file *xib; + unsigned long *p; + + sbinfo = au_sbi(sb); + MtxMustLock(&sbinfo->si_xib_mtx); + AuDebugOn(pindex > ULONG_MAX / PAGE_SIZE + || !au_opt_test(sbinfo->si_mntflags, XINO)); + + if (pindex == sbinfo->si_xib_last_pindex) + return 0; + + xib = sbinfo->si_xib; + p = sbinfo->si_xib_buf; + pos = sbinfo->si_xib_last_pindex; + pos *= PAGE_SIZE; + sz = xino_fwrite(sbinfo->si_xwrite, xib, p, PAGE_SIZE, &pos); + if (unlikely(sz != PAGE_SIZE)) + goto out; + + pos = pindex; + pos *= PAGE_SIZE; + if (vfsub_f_size_read(xib) >= pos + PAGE_SIZE) + sz = xino_fread(sbinfo->si_xread, xib, p, PAGE_SIZE, &pos); + else { + memset(p, 0, PAGE_SIZE); + sz = xino_fwrite(sbinfo->si_xwrite, xib, p, PAGE_SIZE, &pos); + } + if (sz == PAGE_SIZE) { + sbinfo->si_xib_last_pindex = pindex; + return 0; /* success */ + } + +out: + AuIOErr1("write failed (%zd)\n", sz); + err = sz; + if (sz >= 0) + err = -EIO; + return err; +} + +/* ---------------------------------------------------------------------- */ + +static void au_xib_clear_bit(struct inode *inode) +{ + int err, bit; + unsigned long pindex; + struct super_block *sb; + struct au_sbinfo *sbinfo; + + AuDebugOn(inode->i_nlink); + + sb = inode->i_sb; + xib_calc_bit(inode->i_ino, &pindex, &bit); + AuDebugOn(page_bits <= bit); + sbinfo = au_sbi(sb); + mutex_lock(&sbinfo->si_xib_mtx); + err = xib_pindex(sb, pindex); + if (!err) { + clear_bit(bit, sbinfo->si_xib_buf); + sbinfo->si_xib_next_bit = bit; + } + mutex_unlock(&sbinfo->si_xib_mtx); +} + +/* for s_op->delete_inode() */ +void au_xino_delete_inode(struct inode *inode, const int unlinked) +{ + int err; + unsigned int mnt_flags; + aufs_bindex_t bindex, bend, bi; + unsigned char try_trunc; + struct au_iinfo *iinfo; + struct super_block *sb; + struct au_hinode *hi; + struct inode *h_inode; + struct au_branch *br; + vfs_writef_t xwrite; + + sb = inode->i_sb; + mnt_flags = au_mntflags(sb); + if (!au_opt_test(mnt_flags, XINO) + || inode->i_ino == AUFS_ROOT_INO) + return; + + if (unlinked) { + au_xigen_inc(inode); + au_xib_clear_bit(inode); + } + + iinfo = au_ii(inode); + if (!iinfo) + return; + + bindex = iinfo->ii_bstart; + if (bindex < 0) + return; + + xwrite = au_sbi(sb)->si_xwrite; + try_trunc = !!au_opt_test(mnt_flags, TRUNC_XINO); + hi = iinfo->ii_hinode + bindex; + bend = iinfo->ii_bend; + for (; bindex <= bend; bindex++, hi++) { + h_inode = hi->hi_inode; + if (!h_inode + || (!unlinked && h_inode->i_nlink)) + continue; + + /* inode may not be revalidated */ + bi = au_br_index(sb, hi->hi_id); + if (bi < 0) + continue; + + br = au_sbr(sb, bi); + err = au_xino_do_write(xwrite, br->br_xino.xi_file, + h_inode->i_ino, /*ino*/0); + if (!err && try_trunc + && au_test_fs_trunc_xino(au_br_sb(br))) + xino_try_trunc(sb, br); + } +} + +/* get an unused inode number from bitmap */ +ino_t au_xino_new_ino(struct super_block *sb) +{ + ino_t ino; + unsigned long *p, pindex, ul, pend; + struct au_sbinfo *sbinfo; + struct file *file; + int free_bit, err; + + if (!au_opt_test(au_mntflags(sb), XINO)) + return iunique(sb, AUFS_FIRST_INO); + + sbinfo = au_sbi(sb); + mutex_lock(&sbinfo->si_xib_mtx); + p = sbinfo->si_xib_buf; + free_bit = sbinfo->si_xib_next_bit; + if (free_bit < page_bits && !test_bit(free_bit, p)) + goto out; /* success */ + free_bit = find_first_zero_bit(p, page_bits); + if (free_bit < page_bits) + goto out; /* success */ + + pindex = sbinfo->si_xib_last_pindex; + for (ul = pindex - 1; ul < ULONG_MAX; ul--) { + err = xib_pindex(sb, ul); + if (unlikely(err)) + goto out_err; + free_bit = find_first_zero_bit(p, page_bits); + if (free_bit < page_bits) + goto out; /* success */ + } + + file = sbinfo->si_xib; + pend = vfsub_f_size_read(file) / PAGE_SIZE; + for (ul = pindex + 1; ul <= pend; ul++) { + err = xib_pindex(sb, ul); + if (unlikely(err)) + goto out_err; + free_bit = find_first_zero_bit(p, page_bits); + if (free_bit < page_bits) + goto out; /* success */ + } + BUG(); + +out: + set_bit(free_bit, p); + sbinfo->si_xib_next_bit = free_bit + 1; + pindex = sbinfo->si_xib_last_pindex; + mutex_unlock(&sbinfo->si_xib_mtx); + ino = xib_calc_ino(pindex, free_bit); + AuDbg("i%lu\n", (unsigned long)ino); + return ino; +out_err: + mutex_unlock(&sbinfo->si_xib_mtx); + AuDbg("i0\n"); + return 0; +} + +/* + * read @ino from xinofile for the specified branch{@sb, @bindex} + * at the position of @h_ino. + * if @ino does not exist and @do_new is true, get new one. + */ +int au_xino_read(struct super_block *sb, aufs_bindex_t bindex, ino_t h_ino, + ino_t *ino) +{ + int err; + ssize_t sz; + loff_t pos; + struct file *file; + struct au_sbinfo *sbinfo; + + *ino = 0; + if (!au_opt_test(au_mntflags(sb), XINO)) + return 0; /* no xino */ + + err = 0; + sbinfo = au_sbi(sb); + pos = h_ino; + if (unlikely(au_loff_max / sizeof(*ino) - 1 < pos)) { + AuIOErr1("too large hi%lu\n", (unsigned long)h_ino); + return -EFBIG; + } + pos *= sizeof(*ino); + + file = au_sbr(sb, bindex)->br_xino.xi_file; + if (vfsub_f_size_read(file) < pos + sizeof(*ino)) + return 0; /* no ino */ + + sz = xino_fread(sbinfo->si_xread, file, ino, sizeof(*ino), &pos); + if (sz == sizeof(*ino)) + return 0; /* success */ + + err = sz; + if (unlikely(sz >= 0)) { + err = -EIO; + AuIOErr("xino read error (%zd)\n", sz); + } + + return err; +} + +/* ---------------------------------------------------------------------- */ + +/* create and set a new xino file */ + +struct file *au_xino_create(struct super_block *sb, char *fname, int silent) +{ + struct file *file; + struct dentry *h_parent, *d; + struct inode *h_dir, *inode; + int err; + + /* + * at mount-time, and the xino file is the default path, + * hnotify is disabled so we have no notify events to ignore. + * when a user specified the xino, we cannot get au_hdir to be ignored. + */ + file = vfsub_filp_open(fname, O_RDWR | O_CREAT | O_EXCL | O_LARGEFILE + /* | __FMODE_NONOTIFY */, + S_IRUGO | S_IWUGO); + if (IS_ERR(file)) { + if (!silent) + pr_err("open %s(%ld)\n", fname, PTR_ERR(file)); + return file; + } + + /* keep file count */ + err = 0; + inode = file_inode(file); + h_parent = dget_parent(file->f_path.dentry); + h_dir = d_inode(h_parent); + mutex_lock_nested(&h_dir->i_mutex, AuLsc_I_PARENT); + /* mnt_want_write() is unnecessary here */ + /* no delegation since it is just created */ + if (inode->i_nlink) + err = vfsub_unlink(h_dir, &file->f_path, /*delegated*/NULL, + /*force*/0); + mutex_unlock(&h_dir->i_mutex); + dput(h_parent); + if (unlikely(err)) { + if (!silent) + pr_err("unlink %s(%d)\n", fname, err); + goto out; + } + + err = -EINVAL; + d = file->f_path.dentry; + if (unlikely(sb == d->d_sb)) { + if (!silent) + pr_err("%s must be outside\n", fname); + goto out; + } + if (unlikely(au_test_fs_bad_xino(d->d_sb))) { + if (!silent) + pr_err("xino doesn't support %s(%s)\n", + fname, au_sbtype(d->d_sb)); + goto out; + } + return file; /* success */ + +out: + fput(file); + file = ERR_PTR(err); + return file; +} + +/* + * find another branch who is on the same filesystem of the specified + * branch{@btgt}. search until @bend. + */ +static int is_sb_shared(struct super_block *sb, aufs_bindex_t btgt, + aufs_bindex_t bend) +{ + aufs_bindex_t bindex; + struct super_block *tgt_sb = au_sbr_sb(sb, btgt); + + for (bindex = 0; bindex < btgt; bindex++) + if (unlikely(tgt_sb == au_sbr_sb(sb, bindex))) + return bindex; + for (bindex++; bindex <= bend; bindex++) + if (unlikely(tgt_sb == au_sbr_sb(sb, bindex))) + return bindex; + return -1; +} + +/* ---------------------------------------------------------------------- */ + +/* + * initialize the xinofile for the specified branch @br + * at the place/path where @base_file indicates. + * test whether another branch is on the same filesystem or not, + * if @do_test is true. + */ +int au_xino_br(struct super_block *sb, struct au_branch *br, ino_t h_ino, + struct file *base_file, int do_test) +{ + int err; + ino_t ino; + aufs_bindex_t bend, bindex; + struct au_branch *shared_br, *b; + struct file *file; + struct super_block *tgt_sb; + + shared_br = NULL; + bend = au_sbend(sb); + if (do_test) { + tgt_sb = au_br_sb(br); + for (bindex = 0; bindex <= bend; bindex++) { + b = au_sbr(sb, bindex); + if (tgt_sb == au_br_sb(b)) { + shared_br = b; + break; + } + } + } + + if (!shared_br || !shared_br->br_xino.xi_file) { + struct au_xino_lock_dir ldir; + + au_xino_lock_dir(sb, base_file, &ldir); + /* mnt_want_write() is unnecessary here */ + file = au_xino_create2(base_file, NULL); + au_xino_unlock_dir(&ldir); + err = PTR_ERR(file); + if (IS_ERR(file)) + goto out; + br->br_xino.xi_file = file; + } else { + br->br_xino.xi_file = shared_br->br_xino.xi_file; + get_file(br->br_xino.xi_file); + } + + ino = AUFS_ROOT_INO; + err = au_xino_do_write(au_sbi(sb)->si_xwrite, br->br_xino.xi_file, + h_ino, ino); + if (unlikely(err)) { + fput(br->br_xino.xi_file); + br->br_xino.xi_file = NULL; + } + +out: + return err; +} + +/* ---------------------------------------------------------------------- */ + +/* trucate a xino bitmap file */ + +/* todo: slow */ +static int do_xib_restore(struct super_block *sb, struct file *file, void *page) +{ + int err, bit; + ssize_t sz; + unsigned long pindex; + loff_t pos, pend; + struct au_sbinfo *sbinfo; + vfs_readf_t func; + ino_t *ino; + unsigned long *p; + + err = 0; + sbinfo = au_sbi(sb); + MtxMustLock(&sbinfo->si_xib_mtx); + p = sbinfo->si_xib_buf; + func = sbinfo->si_xread; + pend = vfsub_f_size_read(file); + pos = 0; + while (pos < pend) { + sz = xino_fread(func, file, page, PAGE_SIZE, &pos); + err = sz; + if (unlikely(sz <= 0)) + goto out; + + err = 0; + for (ino = page; sz > 0; ino++, sz -= sizeof(ino)) { + if (unlikely(*ino < AUFS_FIRST_INO)) + continue; + + xib_calc_bit(*ino, &pindex, &bit); + AuDebugOn(page_bits <= bit); + err = xib_pindex(sb, pindex); + if (!err) + set_bit(bit, p); + else + goto out; + } + } + +out: + return err; +} + +static int xib_restore(struct super_block *sb) +{ + int err; + aufs_bindex_t bindex, bend; + void *page; + + err = -ENOMEM; + page = (void *)__get_free_page(GFP_NOFS); + if (unlikely(!page)) + goto out; + + err = 0; + bend = au_sbend(sb); + for (bindex = 0; !err && bindex <= bend; bindex++) + if (!bindex || is_sb_shared(sb, bindex, bindex - 1) < 0) + err = do_xib_restore + (sb, au_sbr(sb, bindex)->br_xino.xi_file, page); + else + AuDbg("b%d\n", bindex); + free_page((unsigned long)page); + +out: + return err; +} + +int au_xib_trunc(struct super_block *sb) +{ + int err; + ssize_t sz; + loff_t pos; + struct au_xino_lock_dir ldir; + struct au_sbinfo *sbinfo; + unsigned long *p; + struct file *file; + + SiMustWriteLock(sb); + + err = 0; + sbinfo = au_sbi(sb); + if (!au_opt_test(sbinfo->si_mntflags, XINO)) + goto out; + + file = sbinfo->si_xib; + if (vfsub_f_size_read(file) <= PAGE_SIZE) + goto out; + + au_xino_lock_dir(sb, file, &ldir); + /* mnt_want_write() is unnecessary here */ + file = au_xino_create2(sbinfo->si_xib, NULL); + au_xino_unlock_dir(&ldir); + err = PTR_ERR(file); + if (IS_ERR(file)) + goto out; + fput(sbinfo->si_xib); + sbinfo->si_xib = file; + + p = sbinfo->si_xib_buf; + memset(p, 0, PAGE_SIZE); + pos = 0; + sz = xino_fwrite(sbinfo->si_xwrite, sbinfo->si_xib, p, PAGE_SIZE, &pos); + if (unlikely(sz != PAGE_SIZE)) { + err = sz; + AuIOErr("err %d\n", err); + if (sz >= 0) + err = -EIO; + goto out; + } + + mutex_lock(&sbinfo->si_xib_mtx); + /* mnt_want_write() is unnecessary here */ + err = xib_restore(sb); + mutex_unlock(&sbinfo->si_xib_mtx); + +out: + return err; +} + +/* ---------------------------------------------------------------------- */ + +/* + * xino mount option handlers + */ + +/* xino bitmap */ +static void xino_clear_xib(struct super_block *sb) +{ + struct au_sbinfo *sbinfo; + + SiMustWriteLock(sb); + + sbinfo = au_sbi(sb); + sbinfo->si_xread = NULL; + sbinfo->si_xwrite = NULL; + if (sbinfo->si_xib) + fput(sbinfo->si_xib); + sbinfo->si_xib = NULL; + free_page((unsigned long)sbinfo->si_xib_buf); + sbinfo->si_xib_buf = NULL; +} + +static int au_xino_set_xib(struct super_block *sb, struct file *base) +{ + int err; + loff_t pos; + struct au_sbinfo *sbinfo; + struct file *file; + + SiMustWriteLock(sb); + + sbinfo = au_sbi(sb); + file = au_xino_create2(base, sbinfo->si_xib); + err = PTR_ERR(file); + if (IS_ERR(file)) + goto out; + if (sbinfo->si_xib) + fput(sbinfo->si_xib); + sbinfo->si_xib = file; + sbinfo->si_xread = vfs_readf(file); + sbinfo->si_xwrite = vfs_writef(file); + + err = -ENOMEM; + if (!sbinfo->si_xib_buf) + sbinfo->si_xib_buf = (void *)get_zeroed_page(GFP_NOFS); + if (unlikely(!sbinfo->si_xib_buf)) + goto out_unset; + + sbinfo->si_xib_last_pindex = 0; + sbinfo->si_xib_next_bit = 0; + if (vfsub_f_size_read(file) < PAGE_SIZE) { + pos = 0; + err = xino_fwrite(sbinfo->si_xwrite, file, sbinfo->si_xib_buf, + PAGE_SIZE, &pos); + if (unlikely(err != PAGE_SIZE)) + goto out_free; + } + err = 0; + goto out; /* success */ + +out_free: + free_page((unsigned long)sbinfo->si_xib_buf); + sbinfo->si_xib_buf = NULL; + if (err >= 0) + err = -EIO; +out_unset: + fput(sbinfo->si_xib); + sbinfo->si_xib = NULL; + sbinfo->si_xread = NULL; + sbinfo->si_xwrite = NULL; +out: + return err; +} + +/* xino for each branch */ +static void xino_clear_br(struct super_block *sb) +{ + aufs_bindex_t bindex, bend; + struct au_branch *br; + + bend = au_sbend(sb); + for (bindex = 0; bindex <= bend; bindex++) { + br = au_sbr(sb, bindex); + if (!br || !br->br_xino.xi_file) + continue; + + fput(br->br_xino.xi_file); + br->br_xino.xi_file = NULL; + } +} + +static int au_xino_set_br(struct super_block *sb, struct file *base) +{ + int err; + ino_t ino; + aufs_bindex_t bindex, bend, bshared; + struct { + struct file *old, *new; + } *fpair, *p; + struct au_branch *br; + struct inode *inode; + vfs_writef_t writef; + + SiMustWriteLock(sb); + + err = -ENOMEM; + bend = au_sbend(sb); + fpair = kcalloc(bend + 1, sizeof(*fpair), GFP_NOFS); + if (unlikely(!fpair)) + goto out; + + inode = d_inode(sb->s_root); + ino = AUFS_ROOT_INO; + writef = au_sbi(sb)->si_xwrite; + for (bindex = 0, p = fpair; bindex <= bend; bindex++, p++) { + br = au_sbr(sb, bindex); + bshared = is_sb_shared(sb, bindex, bindex - 1); + if (bshared >= 0) { + /* shared xino */ + *p = fpair[bshared]; + get_file(p->new); + } + + if (!p->new) { + /* new xino */ + p->old = br->br_xino.xi_file; + p->new = au_xino_create2(base, br->br_xino.xi_file); + err = PTR_ERR(p->new); + if (IS_ERR(p->new)) { + p->new = NULL; + goto out_pair; + } + } + + err = au_xino_do_write(writef, p->new, + au_h_iptr(inode, bindex)->i_ino, ino); + if (unlikely(err)) + goto out_pair; + } + + for (bindex = 0, p = fpair; bindex <= bend; bindex++, p++) { + br = au_sbr(sb, bindex); + if (br->br_xino.xi_file) + fput(br->br_xino.xi_file); + get_file(p->new); + br->br_xino.xi_file = p->new; + } + +out_pair: + for (bindex = 0, p = fpair; bindex <= bend; bindex++, p++) + if (p->new) + fput(p->new); + else + break; + kfree(fpair); +out: + return err; +} + +void au_xino_clr(struct super_block *sb) +{ + struct au_sbinfo *sbinfo; + + au_xigen_clr(sb); + xino_clear_xib(sb); + xino_clear_br(sb); + sbinfo = au_sbi(sb); + /* lvalue, do not call au_mntflags() */ + au_opt_clr(sbinfo->si_mntflags, XINO); +} + +int au_xino_set(struct super_block *sb, struct au_opt_xino *xino, int remount) +{ + int err, skip; + struct dentry *parent, *cur_parent; + struct qstr *dname, *cur_name; + struct file *cur_xino; + struct inode *dir; + struct au_sbinfo *sbinfo; + + SiMustWriteLock(sb); + + err = 0; + sbinfo = au_sbi(sb); + parent = dget_parent(xino->file->f_path.dentry); + if (remount) { + skip = 0; + dname = &xino->file->f_path.dentry->d_name; + cur_xino = sbinfo->si_xib; + if (cur_xino) { + cur_parent = dget_parent(cur_xino->f_path.dentry); + cur_name = &cur_xino->f_path.dentry->d_name; + skip = (cur_parent == parent + && au_qstreq(dname, cur_name)); + dput(cur_parent); + } + if (skip) + goto out; + } + + au_opt_set(sbinfo->si_mntflags, XINO); + dir = d_inode(parent); + mutex_lock_nested(&dir->i_mutex, AuLsc_I_PARENT); + /* mnt_want_write() is unnecessary here */ + err = au_xino_set_xib(sb, xino->file); + if (!err) + err = au_xigen_set(sb, xino->file); + if (!err) + err = au_xino_set_br(sb, xino->file); + mutex_unlock(&dir->i_mutex); + if (!err) + goto out; /* success */ + + /* reset all */ + AuIOErr("failed creating xino(%d).\n", err); + au_xigen_clr(sb); + xino_clear_xib(sb); + +out: + dput(parent); + return err; +} + +/* ---------------------------------------------------------------------- */ + +/* + * create a xinofile at the default place/path. + */ +struct file *au_xino_def(struct super_block *sb) +{ + struct file *file; + char *page, *p; + struct au_branch *br; + struct super_block *h_sb; + struct path path; + aufs_bindex_t bend, bindex, bwr; + + br = NULL; + bend = au_sbend(sb); + bwr = -1; + for (bindex = 0; bindex <= bend; bindex++) { + br = au_sbr(sb, bindex); + if (au_br_writable(br->br_perm) + && !au_test_fs_bad_xino(au_br_sb(br))) { + bwr = bindex; + break; + } + } + + if (bwr >= 0) { + file = ERR_PTR(-ENOMEM); + page = (void *)__get_free_page(GFP_NOFS); + if (unlikely(!page)) + goto out; + path.mnt = au_br_mnt(br); + path.dentry = au_h_dptr(sb->s_root, bwr); + p = d_path(&path, page, PATH_MAX - sizeof(AUFS_XINO_FNAME)); + file = (void *)p; + if (!IS_ERR(p)) { + strcat(p, "/" AUFS_XINO_FNAME); + AuDbg("%s\n", p); + file = au_xino_create(sb, p, /*silent*/0); + if (!IS_ERR(file)) + au_xino_brid_set(sb, br->br_id); + } + free_page((unsigned long)page); + } else { + file = au_xino_create(sb, AUFS_XINO_DEFPATH, /*silent*/0); + if (IS_ERR(file)) + goto out; + h_sb = file->f_path.dentry->d_sb; + if (unlikely(au_test_fs_bad_xino(h_sb))) { + pr_err("xino doesn't support %s(%s)\n", + AUFS_XINO_DEFPATH, au_sbtype(h_sb)); + fput(file); + file = ERR_PTR(-EINVAL); + } + if (!IS_ERR(file)) + au_xino_brid_set(sb, -1); + } + +out: + return file; +} + +/* ---------------------------------------------------------------------- */ + +int au_xino_path(struct seq_file *seq, struct file *file) +{ + int err; + + err = au_seq_path(seq, &file->f_path); + if (unlikely(err < 0)) + goto out; + + err = 0; +#define Deleted "\\040(deleted)" + seq->count -= sizeof(Deleted) - 1; + AuDebugOn(memcmp(seq->buf + seq->count, Deleted, + sizeof(Deleted) - 1)); +#undef Deleted + +out: + return err; +} -- cgit v1.2.3