Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S938418AbZDJHX4 (ORCPT ); Fri, 10 Apr 2009 03:23:56 -0400 Received: (majordomo@vger.kernel.org) by vger.kernel.org id S938094AbZDJHSE (ORCPT ); Fri, 10 Apr 2009 03:18:04 -0400 Received: from mfbichi12.ns.itscom.net ([219.110.2.190]:36031 "EHLO mfbichi12.ns.itscom.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S938068AbZDJHR6 (ORCPT ); Fri, 10 Apr 2009 03:17:58 -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 03/29] aufs super_block Date: Fri, 10 Apr 2009 16:02:17 +0900 Message-Id: <1239346963-30953-4-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: 33871 Lines: 1367 initial commit super_block operations and private data Signed-off-by: J. R. Okajima --- fs/aufs/sbinfo.c | 192 ++++++++++++ fs/aufs/super.c | 851 ++++++++++++++++++++++++++++++++++++++++++++++++++++++ fs/aufs/super.h | 285 ++++++++++++++++++ 3 files changed, 1328 insertions(+), 0 deletions(-) create mode 100644 fs/aufs/sbinfo.c create mode 100644 fs/aufs/super.c create mode 100644 fs/aufs/super.h diff --git a/fs/aufs/sbinfo.c b/fs/aufs/sbinfo.c new file mode 100644 index 0000000..12d07f5 --- /dev/null +++ b/fs/aufs/sbinfo.c @@ -0,0 +1,192 @@ +/* + * 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. + */ + +/* + * superblock private data + */ + +#include "aufs.h" + +/* + * they are necessary regardless sysfs is disabled. + */ +void au_si_free(struct kobject *kobj) +{ + struct au_sbinfo *sbinfo; + struct super_block *sb; + + sbinfo = container_of(kobj, struct au_sbinfo, si_kobj); + AuDebugOn(!list_empty(&sbinfo->si_plink.head)); + + sb = sbinfo->si_sb; + si_write_lock(sb); + au_xino_clr(sb); + au_br_free(sbinfo); + kfree(sbinfo->si_branch); + mutex_destroy(&sbinfo->si_xib_mtx); + si_write_unlock(sb); + au_rwsem_destroy(&sbinfo->si_rwsem); + + kfree(sbinfo); +} + +int au_si_alloc(struct super_block *sb) +{ + int err; + struct au_sbinfo *sbinfo; + + err = -ENOMEM; + sbinfo = kmalloc(sizeof(*sbinfo), GFP_NOFS); + if (unlikely(!sbinfo)) + goto out; + + /* will be reallocated separately */ + sbinfo->si_branch = kzalloc(sizeof(*sbinfo->si_branch), GFP_NOFS); + if (unlikely(!sbinfo->si_branch)) + goto out_sbinfo; + + memset(&sbinfo->si_kobj, 0, sizeof(sbinfo->si_kobj)); + err = sysaufs_si_init(sbinfo); + if (unlikely(err)) + goto out_br; + + au_nwt_init(&sbinfo->si_nowait); + init_rwsem(&sbinfo->si_rwsem); + down_write(&sbinfo->si_rwsem); + sbinfo->si_generation = 0; + sbinfo->au_si_status = 0; + sbinfo->si_bend = -1; + sbinfo->si_last_br_id = 0; + + sbinfo->si_wbr_copyup = AuWbrCopyup_Def; + sbinfo->si_wbr_create = AuWbrCreate_Def; + sbinfo->si_wbr_copyup_ops = au_wbr_copyup_ops + AuWbrCopyup_Def; + sbinfo->si_wbr_create_ops = au_wbr_create_ops + AuWbrCreate_Def; + + sbinfo->si_mntflags = AuOpt_Def; + + sbinfo->si_xread = NULL; + sbinfo->si_xwrite = NULL; + sbinfo->si_xib = NULL; + mutex_init(&sbinfo->si_xib_mtx); + sbinfo->si_xib_buf = NULL; + sbinfo->si_xino_brid = -1; + /* leave si_xib_last_pindex and si_xib_next_bit */ + + sbinfo->si_rdcache = AUFS_RDCACHE_DEF * HZ; + sbinfo->si_dirwh = AUFS_DIRWH_DEF; + + au_spl_init(&sbinfo->si_plink); + init_waitqueue_head(&sbinfo->si_plink_wq); + + /* leave other members for sysaufs and si_mnt. */ + sbinfo->si_sb = sb; + sb->s_fs_info = sbinfo; + au_debug_sbinfo_init(sbinfo); + return 0; /* success */ + + out_br: + kfree(sbinfo->si_branch); + out_sbinfo: + kfree(sbinfo); + out: + return err; +} + +int au_sbr_realloc(struct au_sbinfo *sbinfo, int nbr) +{ + int err, sz; + struct au_branch **brp; + + err = -ENOMEM; + sz = sizeof(*brp) * (sbinfo->si_bend + 1); + if (unlikely(!sz)) + sz = sizeof(*brp); + brp = au_kzrealloc(sbinfo->si_branch, sz, sizeof(*brp) * nbr, GFP_NOFS); + if (brp) { + sbinfo->si_branch = brp; + err = 0; + } + + return err; +} + +/* ---------------------------------------------------------------------- */ + +unsigned int au_sigen_inc(struct super_block *sb) +{ + unsigned int gen; + + gen = ++au_sbi(sb)->si_generation; + au_update_digen(sb->s_root); + au_update_iigen(sb->s_root->d_inode); + sb->s_root->d_inode->i_version++; + return gen; +} + +aufs_bindex_t au_new_br_id(struct super_block *sb) +{ + aufs_bindex_t br_id; + int i; + struct au_sbinfo *sbinfo; + + sbinfo = au_sbi(sb); + for (i = 0; i <= AUFS_BRANCH_MAX; i++) { + br_id = ++sbinfo->si_last_br_id; + if (br_id && au_br_index(sb, br_id) < 0) + return br_id; + } + + return -1; +} + +/* ---------------------------------------------------------------------- */ + +/* dentry and super_block lock. call at entry point */ +void aufs_read_lock(struct dentry *dentry, int flags) +{ + si_read_lock(dentry->d_sb, flags); + if (au_ftest_lock(flags, DW)) + di_write_lock_child(dentry); + else + di_read_lock_child(dentry, flags); +} + +void aufs_read_unlock(struct dentry *dentry, int flags) +{ + if (au_ftest_lock(flags, DW)) + di_write_unlock(dentry); + else + di_read_unlock(dentry, flags); + si_read_unlock(dentry->d_sb); +} + +void aufs_write_lock(struct dentry *dentry) +{ + si_write_lock(dentry->d_sb); + di_write_lock_child(dentry); +} + +void aufs_write_unlock(struct dentry *dentry) +{ + di_write_unlock(dentry); + si_write_unlock(dentry->d_sb); +} + +void aufs_read_and_write_lock2(struct dentry *d1, struct dentry *d2, int flags) +{ + si_read_lock(d1->d_sb, flags); + di_write_lock2_child(d1, d2, au_ftest_lock(flags, DIR)); +} + +void aufs_read_and_write_unlock2(struct dentry *d1, struct dentry *d2) +{ + di_write_unlock2(d1, d2); + si_read_unlock(d1->d_sb); +} diff --git a/fs/aufs/super.c b/fs/aufs/super.c new file mode 100644 index 0000000..c8f4c97 --- /dev/null +++ b/fs/aufs/super.c @@ -0,0 +1,851 @@ +/* + * 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. + */ + +/* + * mount and super_block operations + */ + +#include +#include +#include +#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) { + inode_init_once(&c->vfs_inode); + c->vfs_inode.i_version = 1; /* sigen(sb); */ + c->iinfo.ii_hinode = NULL; + return &c->vfs_inode; + } + return NULL; +} + +static void aufs_destroy_inode(struct inode *inode) +{ + au_iinfo_fin(inode); + au_cache_free_icntnr(container_of(inode, struct au_icntnr, vfs_inode)); +} + +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_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 *hd; + struct au_branch *br; + + err = 0; + bend = au_sbend(sb); + hd = 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 = hd[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; + + 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", + sbinfo->si_wbr_mfs.mfs_expire / HZ); + break; + case AuWbrCreate_PMFSV: + seq_printf(m, /*pat*/"pmfs:%lu", + sbinfo->si_wbr_mfs.mfs_expire / HZ); + 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, + sbinfo->si_wbr_mfs.mfs_expire / HZ); + 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; + + 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); + h_root = au_di(sb->s_root)->di_hdentry[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, n; + 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) + + /* 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(PLINK, plink); + /* 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'); + + n = sbinfo->si_dirwh; + if (n != AUFS_DIRWH_DEF) + seq_printf(m, ",dirwh=%d", n); + + n = sbinfo->si_rdcache / HZ; + if (n != AUFS_RDCACHE_DEF) + seq_printf(m, ",rdcache=%d", n); + + 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 Deleted +#undef AuBool +#undef AuStr +} + +/* ---------------------------------------------------------------------- */ + +/* 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 vfsmount *h_mnt; + 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_mnt = au_sbr_mnt(sb, bindex); + h_sb = h_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 */ + err = vfs_statfs(h_mnt->mnt_root, 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 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 */ + err = vfs_statfs(au_sbr_mnt(sb, 0)->mnt_root, buf); + else + err = au_statfs_sum(sb, buf); + si_read_unlock(sb); + + if (!err) { + buf->f_type = AUFS_SUPER_MAGIC; + buf->f_namelen -= AUFS_WH_PFX_LEN; + memset(&buf->f_fsid, 0, sizeof(buf->f_fsid)); + } + /* buf->f_bsize = buf->f_blocks = buf->f_bfree = buf->f_bavail = -1; */ + + return err; +} + +/* ---------------------------------------------------------------------- */ + +/* try flushing the lower fs at aufs remount/unmount time */ + +static void au_fsync_br(struct super_block *sb) +{ + aufs_bindex_t bend, bindex; + int brperm; + struct au_branch *br; + struct super_block *h_sb; + + bend = au_sbend(sb); + for (bindex = 0; bindex < bend; bindex++) { + br = au_sbr(sb, bindex); + brperm = br->br_perm; + if (brperm == AuBrPerm_RR || brperm == AuBrPerm_RRWH) + continue; + h_sb = br->br_mnt->mnt_sb; + if (bdev_read_only(h_sb->s_bdev)) + continue; + + lockdep_off(); + down_write(&h_sb->s_umount); + shrink_dcache_sb(h_sb); + fsync_super(h_sb); + up_write(&h_sb->s_umount); + lockdep_on(); + } +} + +/* + * this IS NOT for super_operations. + * I guess it will be reverted someday. + */ +static void aufs_umount_begin(struct super_block *sb) +{ + struct au_sbinfo *sbinfo; + + sbinfo = au_sbi(sb); + if (!sbinfo) + return; + + si_write_lock(sb); + au_fsync_br(sb); + if (au_opt_test(au_mntflags(sb), PLINK)) + au_plink_put(sb); + if (sbinfo->si_wbr_create_ops->fin) + sbinfo->si_wbr_create_ops->fin(sb); + si_write_unlock(sb); +} + +/* 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; + + aufs_umount_begin(sb); + dbgaufs_si_fin(sbinfo); + kobject_put(&sbinfo->si_kobj); +} + +/* ---------------------------------------------------------------------- */ + +/* + * refresh dentry and inode at remount time. + */ +static int do_refresh(struct dentry *dentry, mode_t type, + unsigned int dir_flags) +{ + int err; + struct dentry *parent; + + di_write_lock_child(dentry); + parent = dget_parent(dentry); + di_read_lock_parent(parent, AuLock_IR); + + /* returns the number of positive dentries */ + err = au_refresh_hdentry(dentry, type); + if (err >= 0) { + struct inode *inode = dentry->d_inode; + err = au_refresh_hinode(inode, dentry); + if (!err && type == S_IFDIR) + au_reset_hinotify(inode, dir_flags); + } + if (unlikely(err)) + AuErr("unrecoverable error %d, %.*s\n", err, AuDLNPair(dentry)); + + di_read_unlock(parent, AuLock_IR); + dput(parent); + di_write_unlock(dentry); + + return err; +} + +static int test_dir(struct dentry *dentry, void *arg __maybe_unused) +{ + return S_ISDIR(dentry->d_inode->i_mode); +} + +/* gave up consolidating with refresh_nondir() */ +static int refresh_dir(struct dentry *root, unsigned int sigen) +{ + int err, i, j, ndentry, e; + struct au_dcsub_pages dpages; + struct au_dpage *dpage; + struct dentry **dentries; + struct inode *inode; + const unsigned int flags = au_hi_flags(root->d_inode, /*isdir*/1); + + err = 0; + list_for_each_entry(inode, &root->d_sb->s_inodes, i_sb_list) + if (S_ISDIR(inode->i_mode) && au_iigen(inode) != sigen) { + ii_write_lock_child(inode); + e = au_refresh_hinode_self(inode, /*do_attr*/1); + ii_write_unlock(inode); + if (unlikely(e)) { + AuDbg("e %d, i%lu\n", e, inode->i_ino); + if (!err) + err = e; + /* go on even if err */ + } + } + + e = au_dpages_init(&dpages, GFP_NOFS); + if (unlikely(e)) { + if (!err) + err = e; + goto out; + } + e = au_dcsub_pages(&dpages, root, test_dir, NULL); + if (unlikely(e)) { + if (!err) + err = e; + goto out_dpages; + } + + for (i = 0; !e && i < dpages.ndpage; i++) { + dpage = dpages.dpages + i; + dentries = dpage->dentries; + ndentry = dpage->ndentry; + for (j = 0; !e && j < ndentry; j++) { + struct dentry *d; + + d = dentries[j]; + au_dbg_verify_dir_parent(d, sigen); + if (au_digen(d) != sigen) { + e = do_refresh(d, S_IFDIR, flags); + if (unlikely(e && !err)) + err = e; + /* break on err */ + } + } + } + + out_dpages: + au_dpages_free(&dpages); + out: + return err; +} + +static int test_nondir(struct dentry *dentry, void *arg __maybe_unused) +{ + return !S_ISDIR(dentry->d_inode->i_mode); +} + +static int refresh_nondir(struct dentry *root, unsigned int sigen, + int do_dentry) +{ + int err, i, j, ndentry, e; + struct au_dcsub_pages dpages; + struct au_dpage *dpage; + struct dentry **dentries; + struct inode *inode; + + err = 0; + list_for_each_entry(inode, &root->d_sb->s_inodes, i_sb_list) + if (!S_ISDIR(inode->i_mode) && au_iigen(inode) != sigen) { + ii_write_lock_child(inode); + e = au_refresh_hinode_self(inode, /*do_attr*/1); + ii_write_unlock(inode); + if (unlikely(e)) { + AuDbg("e %d, i%lu\n", e, inode->i_ino); + if (!err) + err = e; + /* go on even if err */ + } + } + + if (!do_dentry) + goto out; + + e = au_dpages_init(&dpages, GFP_NOFS); + if (unlikely(e)) { + if (!err) + err = e; + goto out; + } + e = au_dcsub_pages(&dpages, root, test_nondir, NULL); + if (unlikely(e)) { + if (!err) + err = e; + goto out_dpages; + } + + for (i = 0; i < dpages.ndpage; i++) { + dpage = dpages.dpages + i; + dentries = dpage->dentries; + ndentry = dpage->ndentry; + for (j = 0; j < ndentry; j++) { + struct dentry *d; + + d = dentries[j]; + au_dbg_verify_nondir_parent(d, sigen); + inode = d->d_inode; + if (inode && au_digen(d) != sigen) { + e = do_refresh(d, inode->i_mode & S_IFMT, + /*dir_flags*/0); + if (unlikely(e && !err)) + err = e; + /* go on even err */ + } + } + } + + out_dpages: + au_dpages_free(&dpages); + out: + return err; +} + +static void au_remount_refresh(struct super_block *sb, unsigned int flags) +{ + int err; + unsigned int sigen; + struct au_sbinfo *sbinfo; + struct dentry *root; + struct inode *inode; + + au_sigen_inc(sb); + sigen = au_sigen(sb); + sbinfo = au_sbi(sb); + au_fclr_si(sbinfo, FAILED_REFRESH_DIRS); + + root = sb->s_root; + DiMustNoWaiters(root); + inode = root->d_inode; + IiMustNoWaiters(inode); + au_reset_hinotify(inode, au_hi_flags(inode, /*isdir*/1)); + di_write_unlock(root); + + err = refresh_dir(root, sigen); + if (unlikely(err)) { + au_fset_si(sbinfo, FAILED_REFRESH_DIRS); + AuWarn("Refreshing directories failed, ignored (%d)\n", err); + } + + if (au_ftest_opts(flags, REFRESH_NONDIR)) { + err = refresh_nondir(root, sigen, !err); + if (unlikely(err)) + AuWarn("Refreshing non-directories failed, ignored" + "(%d)\n", err); + } + + /* aufs_write_lock() calls ..._child() */ + di_write_lock_child(root); + au_cpup_attr_all(root->d_inode, /*force*/1); +} + +/* 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; + struct au_opts opts; + struct dentry *root; + struct inode *inode; + struct au_sbinfo *sbinfo; + + err = 0; + root = sb->s_root; + if (!data || !*data) { + aufs_write_lock(root); + err = au_opts_verify(sb, *flags, /*pending*/0); + if (!err) + au_fsync_br(sb); + 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); + aufs_write_lock(root); + au_fsync_br(sb); + + /* au_opts_remount() may return an error */ + err = au_opts_remount(sb, &opts); + au_opts_free(&opts); + + if (au_ftest_opts(opts.flags, REFRESH_DIR) + || au_ftest_opts(opts.flags, REFRESH_NONDIR)) + au_remount_refresh(sb, opts.flags); + + aufs_write_unlock(root); + mutex_unlock(&inode->i_mutex); + + out_opts: + free_page((unsigned long)opts.opt); + out: + err = cvt_err(err); + AuTraceErr(err); + return err; +} + +static struct super_operations aufs_sop = { + .alloc_inode = aufs_alloc_inode, + .destroy_inode = aufs_destroy_inode, + .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_alloc_dinfo(root); + if (!err) { + sb->s_root = root; + return 0; /* success */ + } + dput(root); + goto out; /* do not iput */ + + out_iput: + iget_failed(inode); + iput(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; + AuErr("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_magic = AUFS_SUPER_MAGIC; + sb->s_maxbytes = 0; + + 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); + inode->i_op = &aufs_dir_iop; + inode->i_fop = &aufs_dir_fop; + aufs_write_lock(root); + err = au_opts_mount(sb, &opts); + au_opts_free(&opts); + if (unlikely(err)) + goto out_unlock; + aufs_write_unlock(root); + mutex_unlock(&inode->i_mutex); + goto out_opts; /* success */ + + out_unlock: + aufs_write_unlock(root); + mutex_unlock(&inode->i_mutex); + 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 int aufs_get_sb(struct file_system_type *fs_type, int flags, + const char *dev_name __maybe_unused, void *raw_data, + struct vfsmount *mnt) +{ + int err; + struct super_block *sb; + + /* all timestamps always follow the ones on the branch */ + /* mnt->mnt_flags |= MNT_NOATIME | MNT_NODIRATIME; */ + err = get_sb_nodev(fs_type, flags, raw_data, aufs_fill_super, mnt); + if (!err) { + sb = mnt->mnt_sb; + si_write_lock(sb); + sysaufs_brs_add(sb, 0); + si_write_unlock(sb); + } + return err; +} + +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 */ + .get_sb = aufs_get_sb, + .kill_sb = generic_shutdown_super, + /* no need to __module_get() and module_put(). */ + .owner = THIS_MODULE, +}; diff --git a/fs/aufs/super.h b/fs/aufs/super.h new file mode 100644 index 0000000..95420ca --- /dev/null +++ b/fs/aufs/super.h @@ -0,0 +1,285 @@ +/* + * 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. + */ + +/* + * super_block operations + */ + +#ifndef __AUFS_SUPER_H__ +#define __AUFS_SUPER_H__ + +#ifdef __KERNEL__ + +#include +#include +#include +#include "rwsem.h" +#include "spl.h" +#include "wkq.h" + +typedef ssize_t (*au_readf_t)(struct file *, char __user *, size_t, loff_t *); +typedef ssize_t (*au_writef_t)(struct file *, const char __user *, size_t, + loff_t *); + +/* policies to select one among multiple writable branches */ +struct au_wbr_copyup_operations { + int (*copyup)(struct dentry *dentry); +}; + +struct au_wbr_create_operations { + int (*create)(struct dentry *dentry, int isdir); + int (*init)(struct super_block *sb); + int (*fin)(struct super_block *sb); +}; + +struct au_wbr_mfs { + struct mutex mfs_lock; /* protect this structure */ + unsigned long mfs_jiffy; + unsigned long mfs_expire; + aufs_bindex_t mfs_bindex; + + unsigned long long mfsrr_bytes; + unsigned long long mfsrr_watermark; +}; + +/* sbinfo status flags */ +/* + * set true when refresh_dirs() failed at remount time. + * then try refreshing dirs at access time again. + * if it is false, refreshing dirs at access time is unnecesary + */ +#define AuSi_FAILED_REFRESH_DIRS 1 +#define AuSi_MAINTAIN_PLINK (1 << 1) /* ioctl */ +#define au_ftest_si(sbinfo, name) ((sbinfo)->au_si_status & AuSi_##name) +#define au_fset_si(sbinfo, name) \ + { (sbinfo)->au_si_status |= AuSi_##name; } +#define au_fclr_si(sbinfo, name) \ + { (sbinfo)->au_si_status &= ~AuSi_##name; } + +struct au_branch; +struct au_sbinfo { + /* nowait tasks in the system-wide workqueue */ + struct au_nowait_tasks si_nowait; + + struct rw_semaphore si_rwsem; + + /* branch management */ + unsigned int si_generation; + + /* see above flags */ + unsigned char au_si_status; + + aufs_bindex_t si_bend; + aufs_bindex_t si_last_br_id; + struct au_branch **si_branch; + + /* policy to select a writable branch */ + unsigned char si_wbr_copyup; + unsigned char si_wbr_create; + struct au_wbr_copyup_operations *si_wbr_copyup_ops; + struct au_wbr_create_operations *si_wbr_create_ops; + + /* round robin */ + atomic_t si_wbr_rr_next; + + /* most free space */ + struct au_wbr_mfs si_wbr_mfs; + + /* mount flags */ + /* include/asm-ia64/siginfo.h defines a macro named si_flags */ + unsigned int si_mntflags; + + /* external inode number (bitmap and translation table) */ + au_readf_t si_xread; + au_writef_t si_xwrite; + struct file *si_xib; + struct mutex si_xib_mtx; /* protect xib members */ + unsigned long *si_xib_buf; + unsigned long si_xib_last_pindex; + int si_xib_next_bit; + aufs_bindex_t si_xino_brid; + /* reserved for future use */ + /* unsigned long long si_xib_limit; */ /* Max xib file size */ + + /* readdir cache time, max, in HZ */ + unsigned long si_rdcache; + + /* + * If the number of whiteouts are larger than si_dirwh, leave all of + * them after au_whtmp_ren to reduce the cost of rmdir(2). + * future fsck.aufs or kernel thread will remove them later. + * Otherwise, remove all whiteouts and the dir in rmdir(2). + */ + unsigned int si_dirwh; + + /* + * rename(2) a directory with all children. + */ + /* reserved for future use */ + /* int si_rendir; */ + + /* pseudo_link list */ + struct au_splhead si_plink; + wait_queue_head_t si_plink_wq; + + /* + * sysfs and lifetime management. + * this is not a small structure and it may be a waste of memory in case + * of sysfs is disabled, particulary when many aufs-es are mounted. + * but using sysfs is majority. + */ + struct kobject si_kobj; +#ifdef CONFIG_DEBUG_FS + struct dentry *si_dbgaufs, *si_dbgaufs_xib; +#ifdef CONFIG_AUFS_EXPORT + struct dentry *si_dbgaufs_xigen; +#endif +#endif + + /* dirty, necessary for unmounting, sysfs and sysrq */ + struct super_block *si_sb; +}; + +/* ---------------------------------------------------------------------- */ + +/* policy to select one among writable branches */ +#define AuWbrCopyup(sbinfo, args...) \ + ((sbinfo)->si_wbr_copyup_ops->copyup(args)) +#define AuWbrCreate(sbinfo, args...) \ + ((sbinfo)->si_wbr_create_ops->create(args)) + +/* flags for si_read_lock()/aufs_read_lock()/di_read_lock() */ +#define AuLock_DW 1 /* write-lock dentry */ +#define AuLock_IR (1 << 1) /* read-lock inode */ +#define AuLock_IW (1 << 2) /* write-lock inode */ +#define AuLock_FLUSH (1 << 3) /* wait for 'nowait' tasks */ +#define AuLock_DIR (1 << 4) /* target is a dir */ +#define au_ftest_lock(flags, name) ((flags) & AuLock_##name) +#define au_fset_lock(flags, name) { (flags) |= AuLock_##name; } +#define au_fclr_lock(flags, name) { (flags) &= ~AuLock_##name; } + +/* ---------------------------------------------------------------------- */ + +/* super.c */ +extern struct file_system_type aufs_fs_type; +struct inode *au_iget_locked(struct super_block *sb, ino_t ino); + +/* sbinfo.c */ +void au_si_free(struct kobject *kobj); +int au_si_alloc(struct super_block *sb); +int au_sbr_realloc(struct au_sbinfo *sbinfo, int nbr); + +unsigned int au_sigen_inc(struct super_block *sb); +aufs_bindex_t au_new_br_id(struct super_block *sb); + +void aufs_read_lock(struct dentry *dentry, int flags); +void aufs_read_unlock(struct dentry *dentry, int flags); +void aufs_write_lock(struct dentry *dentry); +void aufs_write_unlock(struct dentry *dentry); +void aufs_read_and_write_lock2(struct dentry *d1, struct dentry *d2, int isdir); +void aufs_read_and_write_unlock2(struct dentry *d1, struct dentry *d2); + +/* wbr_policy.c */ +extern struct au_wbr_copyup_operations au_wbr_copyup_ops[]; +extern struct au_wbr_create_operations au_wbr_create_ops[]; +int au_cpdown_dirs(struct dentry *dentry, aufs_bindex_t bdst); + +/* ---------------------------------------------------------------------- */ + +static inline struct au_sbinfo *au_sbi(struct super_block *sb) +{ + return sb->s_fs_info; +} + +/* ---------------------------------------------------------------------- */ + +static inline void dbgaufs_si_null(struct au_sbinfo *sbinfo) +{ +#ifdef CONFIG_DEBUG_FS + sbinfo->si_dbgaufs = NULL; + sbinfo->si_dbgaufs_xib = NULL; +#ifdef CONFIG_AUFS_EXPORT + sbinfo->si_dbgaufs_xigen = NULL; +#endif +#endif +} + +/* ---------------------------------------------------------------------- */ + +/* lock superblock. mainly for entry point functions */ +/* + * si_noflush_read_lock, si_noflush_write_lock, + * si_read_unlock, si_write_unlock, si_downgrade_lock + */ +AuSimpleLockRwsemFuncs(si_noflush, struct super_block *sb, + &au_sbi(sb)->si_rwsem); +AuSimpleUnlockRwsemFuncs(si, struct super_block *sb, &au_sbi(sb)->si_rwsem); + +static inline void si_read_lock(struct super_block *sb, int flags) +{ + if (au_ftest_lock(flags, FLUSH)) + au_nwt_flush(&au_sbi(sb)->si_nowait); + si_noflush_read_lock(sb); +} + +static inline void si_write_lock(struct super_block *sb) +{ + au_nwt_flush(&au_sbi(sb)->si_nowait); + si_noflush_write_lock(sb); +} + +static inline int si_read_trylock(struct super_block *sb, int flags) +{ + if (au_ftest_lock(flags, FLUSH)) + au_nwt_flush(&au_sbi(sb)->si_nowait); + return si_noflush_read_trylock(sb); +} + +static inline int si_write_trylock(struct super_block *sb, int flags) +{ + if (au_ftest_lock(flags, FLUSH)) + au_nwt_flush(&au_sbi(sb)->si_nowait); + return si_noflush_write_trylock(sb); +} + +/* ---------------------------------------------------------------------- */ + +static inline aufs_bindex_t au_sbend(struct super_block *sb) +{ + return au_sbi(sb)->si_bend; +} + +static inline unsigned int au_mntflags(struct super_block *sb) +{ + return au_sbi(sb)->si_mntflags; +} + +static inline unsigned int au_sigen(struct super_block *sb) +{ + return au_sbi(sb)->si_generation; +} + +static inline struct au_branch *au_sbr(struct super_block *sb, + aufs_bindex_t bindex) +{ + return au_sbi(sb)->si_branch[0 + bindex]; +} + +static inline void au_xino_brid_set(struct super_block *sb, aufs_bindex_t brid) +{ + au_sbi(sb)->si_xino_brid = brid; +} + +static inline aufs_bindex_t au_xino_brid(struct super_block *sb) +{ + return au_sbi(sb)->si_xino_brid; +} + +#endif /* __KERNEL__ */ +#endif /* __AUFS_SUPER_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/