--- /dev/null
+/*
+ * Copyright (C) 2005-2011 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
+ */
+
+/*
+ * mount and super_block operations
+ */
+
+#include <linux/buffer_head.h>
+#include <linux/jiffies.h>
+#include <linux/module.h>
+#include <linux/seq_file.h>
+#include <linux/statfs.h>
+#include <linux/vmalloc.h>
+#include <linux/writeback.h>
+#include "aufs.h"
+
+/*
+ * super_operations
+ */
+static struct inode *aufs_alloc_inode(struct super_block *sb __maybe_unused)
+{
+ struct au_icntnr *c;
+
+ c = au_cache_alloc_icntnr();
+ if (c) {
+ au_icntnr_init(c);
+ c->vfs_inode.i_version = 1; /* sigen(sb); */
+ c->iinfo.ii_hinode = NULL;
+ return &c->vfs_inode;
+ }
+ return NULL;
+}
+
+static void aufs_destroy_inode_cb(struct rcu_head *head)
+{
+ struct inode *inode = container_of(head, struct inode, i_rcu);
+
+ INIT_LIST_HEAD(&inode->i_dentry);
+ au_cache_free_icntnr(container_of(inode, struct au_icntnr, vfs_inode));
+}
+
+static void aufs_destroy_inode(struct inode *inode)
+{
+ au_iinfo_fin(inode);
+ call_rcu(&inode->i_rcu, aufs_destroy_inode_cb);
+}
+
+struct inode *au_iget_locked(struct super_block *sb, ino_t ino)
+{
+ struct inode *inode;
+ int err;
+
+ inode = iget_locked(sb, ino);
+ if (unlikely(!inode)) {
+ inode = ERR_PTR(-ENOMEM);
+ goto out;
+ }
+ if (!(inode->i_state & I_NEW))
+ goto out;
+
+ err = au_xigen_new(inode);
+ if (!err)
+ err = au_iinfo_init(inode);
+ if (!err)
+ inode->i_version++;
+ else {
+ iget_failed(inode);
+ inode = ERR_PTR(err);
+ }
+
+out:
+ /* never return NULL */
+ AuDebugOn(!inode);
+ AuTraceErrPtr(inode);
+ return inode;
+}
+
+/* lock free root dinfo */
+static int au_show_brs(struct seq_file *seq, struct super_block *sb)
+{
+ int err;
+ aufs_bindex_t bindex, bend;
+ struct path path;
+ struct au_hdentry *hdp;
+ struct au_branch *br;
+
+ err = 0;
+ bend = au_sbend(sb);
+ hdp = au_di(sb->s_root)->di_hdentry;
+ for (bindex = 0; !err && bindex <= bend; bindex++) {
+ br = au_sbr(sb, bindex);
+ path.mnt = br->br_mnt;
+ path.dentry = hdp[bindex].hd_dentry;
+ err = au_seq_path(seq, &path);
+ if (err > 0)
+ err = seq_printf(seq, "=%s",
+ au_optstr_br_perm(br->br_perm));
+ if (!err && bindex != bend)
+ err = seq_putc(seq, ':');
+ }
+
+ return err;
+}
+
+static void au_show_wbr_create(struct seq_file *m, int v,
+ struct au_sbinfo *sbinfo)
+{
+ const char *pat;
+
+ AuRwMustAnyLock(&sbinfo->si_rwsem);
+
+ seq_printf(m, ",create=");
+ pat = au_optstr_wbr_create(v);
+ switch (v) {
+ case AuWbrCreate_TDP:
+ case AuWbrCreate_RR:
+ case AuWbrCreate_MFS:
+ case AuWbrCreate_PMFS:
+ seq_printf(m, pat);
+ break;
+ case AuWbrCreate_MFSV:
+ seq_printf(m, /*pat*/"mfs:%lu",
+ jiffies_to_msecs(sbinfo->si_wbr_mfs.mfs_expire)
+ / MSEC_PER_SEC);
+ break;
+ case AuWbrCreate_PMFSV:
+ seq_printf(m, /*pat*/"pmfs:%lu",
+ jiffies_to_msecs(sbinfo->si_wbr_mfs.mfs_expire)
+ / MSEC_PER_SEC);
+ break;
+ case AuWbrCreate_MFSRR:
+ seq_printf(m, /*pat*/"mfsrr:%llu",
+ sbinfo->si_wbr_mfs.mfsrr_watermark);
+ break;
+ case AuWbrCreate_MFSRRV:
+ seq_printf(m, /*pat*/"mfsrr:%llu:%lu",
+ sbinfo->si_wbr_mfs.mfsrr_watermark,
+ jiffies_to_msecs(sbinfo->si_wbr_mfs.mfs_expire)
+ / MSEC_PER_SEC);
+ break;
+ }
+}
+
+static int au_show_xino(struct seq_file *seq, struct vfsmount *mnt)
+{
+#ifdef CONFIG_SYSFS
+ return 0;
+#else
+ int err;
+ const int len = sizeof(AUFS_XINO_FNAME) - 1;
+ aufs_bindex_t bindex, brid;
+ struct super_block *sb;
+ struct qstr *name;
+ struct file *f;
+ struct dentry *d, *h_root;
+ struct au_hdentry *hdp;
+
+ AuRwMustAnyLock(&sbinfo->si_rwsem);
+
+ err = 0;
+ sb = mnt->mnt_sb;
+ f = au_sbi(sb)->si_xib;
+ if (!f)
+ goto out;
+
+ /* stop printing the default xino path on the first writable branch */
+ h_root = NULL;
+ brid = au_xino_brid(sb);
+ if (brid >= 0) {
+ bindex = au_br_index(sb, brid);
+ hdp = au_di(sb->s_root)->di_hdentry;
+ h_root = hdp[0 + bindex].hd_dentry;
+ }
+ d = f->f_dentry;
+ name = &d->d_name;
+ /* safe ->d_parent because the file is unlinked */
+ if (d->d_parent == h_root
+ && name->len == len
+ && !memcmp(name->name, AUFS_XINO_FNAME, len))
+ goto out;
+
+ seq_puts(seq, ",xino=");
+ err = au_xino_path(seq, f);
+
+out:
+ return err;
+#endif
+}
+
+/* seq_file will re-call me in case of too long string */
+static int aufs_show_options(struct seq_file *m, struct vfsmount *mnt)
+{
+ int err;
+ unsigned int mnt_flags, v;
+ struct super_block *sb;
+ struct au_sbinfo *sbinfo;
+
+#define AuBool(name, str) do { \
+ v = au_opt_test(mnt_flags, name); \
+ if (v != au_opt_test(AuOpt_Def, name)) \
+ seq_printf(m, ",%s" #str, v ? "" : "no"); \
+} while (0)
+
+#define AuStr(name, str) do { \
+ v = mnt_flags & AuOptMask_##name; \
+ if (v != (AuOpt_Def & AuOptMask_##name)) \
+ seq_printf(m, "," #str "=%s", au_optstr_##str(v)); \
+} while (0)
+
+#define AuUInt(name, str, val) do { \
+ if (val != AUFS_##name##_DEF) \
+ seq_printf(m, "," #str "=%u", val); \
+} while (0)
+
+ /* lock free root dinfo */
+ sb = mnt->mnt_sb;
+ si_noflush_read_lock(sb);
+ sbinfo = au_sbi(sb);
+ seq_printf(m, ",si=%lx", sysaufs_si_id(sbinfo));
+
+ mnt_flags = au_mntflags(sb);
+ if (au_opt_test(mnt_flags, XINO)) {
+ err = au_show_xino(m, mnt);
+ if (unlikely(err))
+ goto out;
+ } else
+ seq_puts(m, ",noxino");
+
+ AuBool(TRUNC_XINO, trunc_xino);
+ AuStr(UDBA, udba);
+ AuBool(SHWH, shwh);
+ AuBool(PLINK, plink);
+ AuBool(DIO, dio);
+ /* AuBool(DIRPERM1, dirperm1); */
+ /* AuBool(REFROF, refrof); */
+
+ v = sbinfo->si_wbr_create;
+ if (v != AuWbrCreate_Def)
+ au_show_wbr_create(m, v, sbinfo);
+
+ v = sbinfo->si_wbr_copyup;
+ if (v != AuWbrCopyup_Def)
+ seq_printf(m, ",cpup=%s", au_optstr_wbr_copyup(v));
+
+ v = au_opt_test(mnt_flags, ALWAYS_DIROPQ);
+ if (v != au_opt_test(AuOpt_Def, ALWAYS_DIROPQ))
+ seq_printf(m, ",diropq=%c", v ? 'a' : 'w');
+
+ AuUInt(DIRWH, dirwh, sbinfo->si_dirwh);
+
+ v = jiffies_to_msecs(sbinfo->si_rdcache) / MSEC_PER_SEC;
+ AuUInt(RDCACHE, rdcache, v);
+
+ AuUInt(RDBLK, rdblk, sbinfo->si_rdblk);
+ AuUInt(RDHASH, rdhash, sbinfo->si_rdhash);
+
+ AuBool(SUM, sum);
+ /* AuBool(SUM_W, wsum); */
+ AuBool(WARN_PERM, warn_perm);
+ AuBool(VERBOSE, verbose);
+
+out:
+ /* be sure to print "br:" last */
+ if (!sysaufs_brs) {
+ seq_puts(m, ",br:");
+ au_show_brs(m, sb);
+ }
+ si_read_unlock(sb);
+ return 0;
+
+#undef AuBool
+#undef AuStr
+#undef AuUInt
+}
+
+/* ---------------------------------------------------------------------- */
+
+/* sum mode which returns the summation for statfs(2) */
+
+static u64 au_add_till_max(u64 a, u64 b)
+{
+ u64 old;
+
+ old = a;
+ a += b;
+ if (old < a)
+ return a;
+ return ULLONG_MAX;
+}
+
+static int au_statfs_sum(struct super_block *sb, struct kstatfs *buf)
+{
+ int err;
+ u64 blocks, bfree, bavail, files, ffree;
+ aufs_bindex_t bend, bindex, i;
+ unsigned char shared;
+ struct path h_path;
+ struct super_block *h_sb;
+
+ blocks = 0;
+ bfree = 0;
+ bavail = 0;
+ files = 0;
+ ffree = 0;
+
+ err = 0;
+ bend = au_sbend(sb);
+ for (bindex = bend; bindex >= 0; bindex--) {
+ h_path.mnt = au_sbr_mnt(sb, bindex);
+ h_sb = h_path.mnt->mnt_sb;
+ shared = 0;
+ for (i = bindex + 1; !shared && i <= bend; i++)
+ shared = (au_sbr_sb(sb, i) == h_sb);
+ if (shared)
+ continue;
+
+ /* sb->s_root for NFS is unreliable */
+ h_path.dentry = h_path.mnt->mnt_root;
+ err = vfs_statfs(&h_path, buf);
+ if (unlikely(err))
+ goto out;
+
+ blocks = au_add_till_max(blocks, buf->f_blocks);
+ bfree = au_add_till_max(bfree, buf->f_bfree);
+ bavail = au_add_till_max(bavail, buf->f_bavail);
+ files = au_add_till_max(files, buf->f_files);
+ ffree = au_add_till_max(ffree, buf->f_ffree);
+ }
+
+ buf->f_blocks = blocks;
+ buf->f_bfree = bfree;
+ buf->f_bavail = bavail;
+ buf->f_files = files;
+ buf->f_ffree = ffree;
+
+out:
+ return err;
+}
+
+static int aufs_statfs(struct dentry *dentry, struct kstatfs *buf)
+{
+ int err;
+ struct path h_path;
+ struct super_block *sb;
+
+ /* lock free root dinfo */
+ sb = dentry->d_sb;
+ si_noflush_read_lock(sb);
+ if (!au_opt_test(au_mntflags(sb), SUM)) {
+ /* sb->s_root for NFS is unreliable */
+ h_path.mnt = au_sbr_mnt(sb, 0);
+ h_path.dentry = h_path.mnt->mnt_root;
+ err = vfs_statfs(&h_path, buf);
+ } else
+ err = au_statfs_sum(sb, buf);
+ si_read_unlock(sb);
+
+ if (!err) {
+ buf->f_type = AUFS_SUPER_MAGIC;
+ buf->f_namelen = AUFS_MAX_NAMELEN;
+ memset(&buf->f_fsid, 0, sizeof(buf->f_fsid));
+ }
+ /* buf->f_bsize = buf->f_blocks = buf->f_bfree = buf->f_bavail = -1; */
+
+ return err;
+}
+
+/* ---------------------------------------------------------------------- */
+
+/* final actions when unmounting a file system */
+static void aufs_put_super(struct super_block *sb)
+{
+ struct au_sbinfo *sbinfo;
+
+ sbinfo = au_sbi(sb);
+ if (!sbinfo)
+ return;
+
+ dbgaufs_si_fin(sbinfo);
+ kobject_put(&sbinfo->si_kobj);
+}
+
+/* ---------------------------------------------------------------------- */
+
+void au_array_free(void *array)
+{
+ if (array) {
+ if (!is_vmalloc_addr(array))
+ kfree(array);
+ else
+ vfree(array);
+ }
+}
+
+void *au_array_alloc(unsigned long long *hint, au_arraycb_t cb, void *arg)
+{
+ void *array;
+ unsigned long long n;
+
+ array = NULL;
+ n = 0;
+ if (!*hint)
+ goto out;
+
+ if (*hint > ULLONG_MAX / sizeof(array)) {
+ array = ERR_PTR(-EMFILE);
+ pr_err("hint %llu\n", *hint);
+ goto out;
+ }
+
+ array = kmalloc(sizeof(array) * *hint, GFP_NOFS);
+ if (unlikely(!array))
+ array = vmalloc(sizeof(array) * *hint);
+ if (unlikely(!array)) {
+ array = ERR_PTR(-ENOMEM);
+ goto out;
+ }
+
+ n = cb(array, *hint, arg);
+ AuDebugOn(n > *hint);
+
+out:
+ *hint = n;
+ return array;
+}
+
+static unsigned long long au_iarray_cb(void *a,
+ unsigned long long max __maybe_unused,
+ void *arg)
+{
+ unsigned long long n;
+ struct inode **p, *inode;
+ struct list_head *head;
+
+ n = 0;
+ p = a;
+ head = arg;
+ spin_lock(&inode_sb_list_lock);
+ list_for_each_entry(inode, head, i_sb_list) {
+ if (!is_bad_inode(inode)
+ && au_ii(inode)->ii_bstart >= 0) {
+ spin_lock(&inode->i_lock);
+ if (atomic_read(&inode->i_count)) {
+ au_igrab(inode);
+ *p++ = inode;
+ n++;
+ AuDebugOn(n > max);
+ }
+ spin_unlock(&inode->i_lock);
+ }
+ }
+ spin_unlock(&inode_sb_list_lock);
+
+ return n;
+}
+
+struct inode **au_iarray_alloc(struct super_block *sb, unsigned long long *max)
+{
+ *max = atomic_long_read(&au_sbi(sb)->si_ninodes);
+ return au_array_alloc(max, au_iarray_cb, &sb->s_inodes);
+}
+
+void au_iarray_free(struct inode **a, unsigned long long max)
+{
+ unsigned long long ull;
+
+ for (ull = 0; ull < max; ull++)
+ iput(a[ull]);
+ au_array_free(a);
+}
+
+/* ---------------------------------------------------------------------- */
+
+/*
+ * refresh dentry and inode at remount time.
+ */
+/* todo: consolidate with simple_reval_dpath() and au_reval_for_attr() */
+static int au_do_refresh(struct dentry *dentry, unsigned int dir_flags,
+ struct dentry *parent)
+{
+ int err;
+
+ di_write_lock_child(dentry);
+ di_read_lock_parent(parent, AuLock_IR);
+ err = au_refresh_dentry(dentry, parent);
+ if (!err && dir_flags)
+ au_hn_reset(dentry->d_inode, dir_flags);
+ di_read_unlock(parent, AuLock_IR);
+ di_write_unlock(dentry);
+
+ return err;
+}
+
+static int au_do_refresh_d(struct dentry *dentry, unsigned int sigen,
+ struct au_sbinfo *sbinfo,
+ const unsigned int dir_flags)
+{
+ int err;
+ struct dentry *parent;
+ struct inode *inode;
+
+ err = 0;
+ parent = dget_parent(dentry);
+ if (!au_digen_test(parent, sigen) && au_digen_test(dentry, sigen)) {
+ inode = dentry->d_inode;
+ if (inode) {
+ if (!S_ISDIR(inode->i_mode))
+ err = au_do_refresh(dentry, /*dir_flags*/0,
+ parent);
+ else {
+ err = au_do_refresh(dentry, dir_flags, parent);
+ if (unlikely(err))
+ au_fset_si(sbinfo, FAILED_REFRESH_DIR);
+ }
+ } else
+ err = au_do_refresh(dentry, /*dir_flags*/0, parent);
+ AuDbgDentry(dentry);
+ }
+ dput(parent);
+
+ AuTraceErr(err);
+ return err;
+}
+
+static int au_refresh_d(struct super_block *sb)
+{
+ int err, i, j, ndentry, e;
+ unsigned int sigen;
+ struct au_dcsub_pages dpages;
+ struct au_dpage *dpage;
+ struct dentry **dentries, *d;
+ struct au_sbinfo *sbinfo;
+ struct dentry *root = sb->s_root;
+ const unsigned int dir_flags = au_hi_flags(root->d_inode, /*isdir*/1);
+
+ 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;
+
+ sigen = au_sigen(sb);
+ sbinfo = au_sbi(sb);
+ for (i = 0; i < dpages.ndpage; i++) {
+ dpage = dpages.dpages + i;
+ dentries = dpage->dentries;
+ ndentry = dpage->ndentry;
+ for (j = 0; j < ndentry; j++) {
+ d = dentries[j];
+ e = au_do_refresh_d(d, sigen, sbinfo, dir_flags);
+ if (unlikely(e && !err))
+ err = e;
+ /* go on even err */
+ }
+ }
+
+out_dpages:
+ au_dpages_free(&dpages);
+out:
+ return err;
+}
+
+static int au_refresh_i(struct super_block *sb)
+{
+ int err, e;
+ unsigned int sigen;
+ unsigned long long max, ull;
+ struct inode *inode, **array;
+
+ array = au_iarray_alloc(sb, &max);
+ err = PTR_ERR(array);
+ if (IS_ERR(array))
+ goto out;
+
+ err = 0;
+ sigen = au_sigen(sb);
+ for (ull = 0; ull < max; ull++) {
+ inode = array[ull];
+ if (au_iigen(inode) != sigen) {
+ ii_write_lock_child(inode);
+ e = au_refresh_hinode_self(inode);
+ ii_write_unlock(inode);
+ if (unlikely(e)) {
+ pr_err("error %d, i%lu\n", e, inode->i_ino);
+ if (!err)
+ err = e;
+ /* go on even if err */
+ }
+ }
+ }
+
+ au_iarray_free(array, max);
+
+out:
+ return err;
+}
+
+static void au_remount_refresh(struct super_block *sb)
+{
+ int err, e;
+ unsigned int udba;
+ aufs_bindex_t bindex, bend;
+ struct dentry *root;
+ struct inode *inode;
+ struct au_branch *br;
+
+ au_sigen_inc(sb);
+ au_fclr_si(au_sbi(sb), FAILED_REFRESH_DIR);
+
+ root = sb->s_root;
+ DiMustNoWaiters(root);
+ inode = root->d_inode;
+ IiMustNoWaiters(inode);
+
+ udba = au_opt_udba(sb);
+ bend = au_sbend(sb);
+ for (bindex = 0; bindex <= bend; bindex++) {
+ br = au_sbr(sb, bindex);
+ err = au_hnotify_reset_br(udba, br, br->br_perm);
+ if (unlikely(err))
+ AuIOErr("hnotify failed on br %d, %d, ignored\n",
+ bindex, err);
+ /* go on even if err */
+ }
+ au_hn_reset(inode, au_hi_flags(inode, /*isdir*/1));
+
+ di_write_unlock(root);
+ err = au_refresh_d(sb);
+ e = au_refresh_i(sb);
+ if (unlikely(e && !err))
+ err = e;
+ /* aufs_write_lock() calls ..._child() */
+ di_write_lock_child(root);
+
+ au_cpup_attr_all(inode, /*force*/1);
+
+ if (unlikely(err))
+ AuIOErr("refresh failed, ignored, %d\n", err);
+}
+
+/* stop extra interpretation of errno in mount(8), and strange error messages */
+static int cvt_err(int err)
+{
+ AuTraceErr(err);
+
+ switch (err) {
+ case -ENOENT:
+ case -ENOTDIR:
+ case -EEXIST:
+ case -EIO:
+ err = -EINVAL;
+ }
+ return err;
+}
+
+static int aufs_remount_fs(struct super_block *sb, int *flags, char *data)
+{
+ int err, do_dx;
+ unsigned int mntflags;
+ struct au_opts opts;
+ struct dentry *root;
+ struct inode *inode;
+ struct au_sbinfo *sbinfo;
+
+ err = 0;
+ root = sb->s_root;
+ if (!data || !*data) {
+ err = si_write_lock(sb, AuLock_FLUSH | AuLock_NOPLM);
+ if (!err) {
+ di_write_lock_child(root);
+ err = au_opts_verify(sb, *flags, /*pending*/0);
+ aufs_write_unlock(root);
+ }
+ goto out;
+ }
+
+ err = -ENOMEM;
+ memset(&opts, 0, sizeof(opts));
+ opts.opt = (void *)__get_free_page(GFP_NOFS);
+ if (unlikely(!opts.opt))
+ goto out;
+ opts.max_opt = PAGE_SIZE / sizeof(*opts.opt);
+ opts.flags = AuOpts_REMOUNT;
+ opts.sb_flags = *flags;
+
+ /* parse it before aufs lock */
+ err = au_opts_parse(sb, data, &opts);
+ if (unlikely(err))
+ goto out_opts;
+
+ sbinfo = au_sbi(sb);
+ inode = root->d_inode;
+ mutex_lock(&inode->i_mutex);
+ err = si_write_lock(sb, AuLock_FLUSH | AuLock_NOPLM);
+ if (unlikely(err))
+ goto out_mtx;
+ di_write_lock_child(root);
+
+ /* au_opts_remount() may return an error */
+ err = au_opts_remount(sb, &opts);
+ au_opts_free(&opts);
+
+ if (au_ftest_opts(opts.flags, REFRESH))
+ au_remount_refresh(sb);
+
+ if (au_ftest_opts(opts.flags, REFRESH_DYAOP)) {
+ mntflags = au_mntflags(sb);
+ do_dx = !!au_opt_test(mntflags, DIO);
+ au_dy_arefresh(do_dx);
+ }
+
+ aufs_write_unlock(root);
+
+out_mtx:
+ mutex_unlock(&inode->i_mutex);
+out_opts:
+ free_page((unsigned long)opts.opt);
+out:
+ err = cvt_err(err);
+ AuTraceErr(err);
+ return err;
+}
+
+static const struct super_operations aufs_sop = {
+ .alloc_inode = aufs_alloc_inode,
+ .destroy_inode = aufs_destroy_inode,
+ /* always deleting, no clearing */
+ .drop_inode = generic_delete_inode,
+ .show_options = aufs_show_options,
+ .statfs = aufs_statfs,
+ .put_super = aufs_put_super,
+ .remount_fs = aufs_remount_fs
+};
+
+/* ---------------------------------------------------------------------- */
+
+static int alloc_root(struct super_block *sb)
+{
+ int err;
+ struct inode *inode;
+ struct dentry *root;
+
+ err = -ENOMEM;
+ inode = au_iget_locked(sb, AUFS_ROOT_INO);
+ err = PTR_ERR(inode);
+ if (IS_ERR(inode))
+ goto out;
+
+ inode->i_op = &aufs_dir_iop;
+ inode->i_fop = &aufs_dir_fop;
+ inode->i_mode = S_IFDIR;
+ inode->i_nlink = 2;
+ unlock_new_inode(inode);
+
+ root = d_alloc_root(inode);
+ if (unlikely(!root))
+ goto out_iput;
+ err = PTR_ERR(root);
+ if (IS_ERR(root))
+ goto out_iput;
+
+ err = au_di_init(root);
+ if (!err) {
+ sb->s_root = root;
+ return 0; /* success */
+ }
+ dput(root);
+ goto out; /* do not iput */
+
+out_iput:
+ iget_failed(inode);
+out:
+ return err;
+
+}
+
+static int aufs_fill_super(struct super_block *sb, void *raw_data,
+ int silent __maybe_unused)
+{
+ int err;
+ struct au_opts opts;
+ struct dentry *root;
+ struct inode *inode;
+ char *arg = raw_data;
+
+ if (unlikely(!arg || !*arg)) {
+ err = -EINVAL;
+ pr_err("no arg\n");
+ goto out;
+ }
+
+ err = -ENOMEM;
+ memset(&opts, 0, sizeof(opts));
+ opts.opt = (void *)__get_free_page(GFP_NOFS);
+ if (unlikely(!opts.opt))
+ goto out;
+ opts.max_opt = PAGE_SIZE / sizeof(*opts.opt);
+ opts.sb_flags = sb->s_flags;
+
+ err = au_si_alloc(sb);
+ if (unlikely(err))
+ goto out_opts;
+
+ /* all timestamps always follow the ones on the branch */
+ sb->s_flags |= MS_NOATIME | MS_NODIRATIME;
+ sb->s_op = &aufs_sop;
+ sb->s_d_op = &aufs_dop;
+ sb->s_magic = AUFS_SUPER_MAGIC;
+ sb->s_maxbytes = 0;
+ au_export_init(sb);
+
+ err = alloc_root(sb);
+ if (unlikely(err)) {
+ si_write_unlock(sb);
+ goto out_info;
+ }
+ root = sb->s_root;
+ inode = root->d_inode;
+
+ /*
+ * actually we can parse options regardless aufs lock here.
+ * but at remount time, parsing must be done before aufs lock.
+ * so we follow the same rule.
+ */
+ ii_write_lock_parent(inode);
+ aufs_write_unlock(root);
+ err = au_opts_parse(sb, arg, &opts);
+ if (unlikely(err))
+ goto out_root;
+
+ /* lock vfs_inode first, then aufs. */
+ mutex_lock(&inode->i_mutex);
+ aufs_write_lock(root);
+ err = au_opts_mount(sb, &opts);
+ au_opts_free(&opts);
+ aufs_write_unlock(root);
+ mutex_unlock(&inode->i_mutex);
+ if (!err)
+ goto out_opts; /* success */
+
+out_root:
+ dput(root);
+ sb->s_root = NULL;
+out_info:
+ kobject_put(&au_sbi(sb)->si_kobj);
+ sb->s_fs_info = NULL;
+out_opts:
+ free_page((unsigned long)opts.opt);
+out:
+ AuTraceErr(err);
+ err = cvt_err(err);
+ AuTraceErr(err);
+ return err;
+}
+
+/* ---------------------------------------------------------------------- */
+
+static struct dentry *aufs_mount(struct file_system_type *fs_type, int flags,
+ const char *dev_name __maybe_unused,
+ void *raw_data)
+{
+ struct dentry *root;
+ struct super_block *sb;
+
+ /* all timestamps always follow the ones on the branch */
+ /* mnt->mnt_flags |= MNT_NOATIME | MNT_NODIRATIME; */
+ root = mount_nodev(fs_type, flags, raw_data, aufs_fill_super);
+ if (IS_ERR(root))
+ goto out;
+
+ sb = root->d_sb;
+ si_write_lock(sb, !AuLock_FLUSH);
+ sysaufs_brs_add(sb, 0);
+ si_write_unlock(sb);
+ au_sbilist_add(sb);
+
+out:
+ return root;
+}
+
+static void aufs_kill_sb(struct super_block *sb)
+{
+ struct au_sbinfo *sbinfo;
+
+ sbinfo = au_sbi(sb);
+ if (sbinfo) {
+ au_sbilist_del(sb);
+ aufs_write_lock(sb->s_root);
+ if (sbinfo->si_wbr_create_ops->fin)
+ sbinfo->si_wbr_create_ops->fin(sb);
+ if (au_opt_test(sbinfo->si_mntflags, UDBA_HNOTIFY)) {
+ au_opt_set_udba(sbinfo->si_mntflags, UDBA_NONE);
+ au_remount_refresh(sb);
+ }
+ if (au_opt_test(sbinfo->si_mntflags, PLINK))
+ au_plink_put(sb, /*verbose*/1);
+ au_xino_clr(sb);
+ aufs_write_unlock(sb->s_root);
+ au_nwt_flush(&sbinfo->si_nowait);
+ }
+ generic_shutdown_super(sb);
+}
+
+struct file_system_type aufs_fs_type = {
+ .name = AUFS_FSTYPE,
+ .fs_flags =
+ FS_RENAME_DOES_D_MOVE /* a race between rename and others */
+ | FS_REVAL_DOT, /* for NFS branch and udba */
+ .mount = aufs_mount,
+ .kill_sb = aufs_kill_sb,
+ /* no need to __module_get() and module_put(). */
+ .owner = THIS_MODULE,
+};
git.openpandora.org / pandora-kernel.git / blobdiff