From: Junjiro Okajima <hooanon05@xxxxxxxxxxx> initial commit aufs super_block operations Signed-off-by: Junjiro Okajima <hooanon05@xxxxxxxxxxx> --- fs/aufs/super.h | 410 +++++++++++++++++++++++++++++++++++++++++++++++++++++++ 1 files changed, 410 insertions(+), 0 deletions(-) diff --git a/fs/aufs/super.h b/fs/aufs/super.h new file mode 100644 index 0000000..f6e6d8b --- /dev/null +++ b/fs/aufs/super.h @@ -0,0 +1,410 @@ +/* + * Copyright (C) 2005-2008 Junjiro 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 + */ + +/* + * super_block operations + * + * $Id: super.h,v 1.4 2008/05/04 23:52:41 sfjro Exp $ + */ + +#ifndef __AUFS_SUPER_H__ +#define __AUFS_SUPER_H__ + +#ifdef __KERNEL__ + +#include <linux/fs.h> +#include <linux/cramfs_fs.h> +#include <linux/kobject.h> +#include <linux/magic.h> +#include <linux/aufs_type.h> +//#include "hinode.h" +#include "misc.h" +//#include "opts.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 *); + +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; + + u64 mfsrr_bytes; + u64 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_FAILED_INIT (1 << 1) +#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 au_rwsem si_rwsem; + + /* branch management */ + au_gen_t 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; + //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. + */ + //int si_rendir; + + /* pseudo_link list */ // dirty + spinlock_t si_plink_lock; + struct list_head si_plink; + + /* dirty, for export, async ops, and sysfs */ + spinlock_t si_mntcache_lock; + struct vfsmount *si_mntcache; /* no get/put */ + + /* + * 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. + */ + struct kobject si_kobj; + + //todo: remove this list. + /* super_blocks list is not exported */ + struct list_head si_list; + +#ifdef CONFIG_AUFS_ROBR + /* locked vma list for mmap() */ // dirty + spinlock_t si_lvma_lock; + struct list_head si_lvma; +#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); +struct au_branch *au_sbr(struct super_block *sb, aufs_bindex_t bindex); +au_gen_t au_sigen_inc(struct super_block *sb); +int au_find_bindex(struct super_block *sb, struct au_branch *br); + +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); + +aufs_bindex_t au_new_br_id(struct super_block *sb); +struct vfsmount *au_mntcache_get(struct super_block *sb); + +/* 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, + struct dentry *locked); + +/* ---------------------------------------------------------------------- */ + +static inline struct au_sbinfo *au_sbi(struct super_block *sb) +{ + return sb->s_fs_info; +} + +static inline const char *au_sbtype(struct super_block *sb) +{ + return sb->s_type->name; +} + +static inline int au_test_aufs(struct super_block *sb) +{ + return (sb->s_magic == AUFS_SUPER_MAGIC); +} + +static inline int au_test_nfs(struct super_block *sb) +{ +#ifdef CONFIG_AUFS_BR_NFS + return (sb->s_magic == NFS_SUPER_MAGIC); +#else + return 0; +#endif +} + +static inline int au_test_fuse(struct super_block *sb) +{ +#ifdef CONFIG_AUFS_WORKAROUND_FUSE +#ifdef FUSE_SUPER_MAGIC + BUILD_BUG_ON(FUSE_SUPER_MAGIC != 0x65735546); + return (sb->s_magic == FUSE_SUPER_MAGIC); +#else + return !strcmp(au_sbtype(sb), "fuse"); +#endif +#endif + return 0; +} + +static inline int au_test_xfs(struct super_block *sb) +{ +#ifdef CONFIG_AUFS_BR_XFS +#ifdef XFS_SB_MAGIC + BUILD_BUG_ON(XFS_SB_MAGIC != 0x58465342); + return (sb->s_magic == XFS_SB_MAGIC); +#else + return !strcmp(au_sbtype(sb), "xfs"); +#endif +#endif + return 0; +} + +static inline int au_test_tmpfs(struct super_block *sb) +{ +#ifdef CONFIG_TMPFS +#ifdef TMPFS_MAGIC + BUILD_BUG_ON(TMPFS_MAGIC != 0x01021994); + return (sb->s_magic == TMPFS_MAGIC); +#else + return !strcmp(au_sbtype(sb), "tmpfs"); +#endif +#endif + return 0; +} + +/* ---------------------------------------------------------------------- */ + +#ifdef CONFIG_AUFS_EXPORT +extern struct export_operations aufs_export_op; +static inline void au_init_export_op(struct super_block *sb) +{ + sb->s_export_op = &aufs_export_op; +} + +static inline int au_test_nfsd(struct task_struct *tsk) +{ + return (!tsk->mm && !strcmp(tsk->comm, "nfsd")); +} + +static inline void au_nfsd_lockdep_off(void) +{ + if (au_test_nfsd(current)) + lockdep_off(); +} + +static inline void au_nfsd_lockdep_on(void) +{ + if (au_test_nfsd(current)) + lockdep_on(); +} +#else +static inline int au_test_nfsd(struct task_struct *tsk) +{ + return 0; +} + +static inline void au_init_export_op(struct super_block *sb) +{ + /* nothing */ +} + +#define au_nfsd_lockdep_off() do {} while (0) +#define au_nfsd_lockdep_on() do {} while (0) +#endif /* CONFIG_AUFS_EXPORT */ + +#ifdef CONFIG_AUFS_ROBR +static inline int au_test_nested(struct super_block *h_sb) +{ + return 0; +} + +static inline void au_robr_lvma_init(struct au_sbinfo *sbinfo) +{ + spin_lock_init(&sbinfo->si_lvma_lock); + INIT_LIST_HEAD(&sbinfo->si_lvma); +} +#else +static inline int au_test_nested(struct super_block *h_sb) +{ + int err = 0; + if (unlikely(au_test_aufs(h_sb))) { + err = -EINVAL; + AuTraceErr(err); + } + return err; +} + +static inline void au_robr_lvma_init(struct au_sbinfo *sbinfo) +{ + /* empty */ +} +#endif /* CONFIG_AUFS_ROBR */ + +/* ---------------------------------------------------------------------- */ + +/* 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); +} + +/* to debug easier, do not make them inlined functions */ +#define SiMustReadLock(sb) AuRwMustReadLock(&au_sbi(sb)->si_rwsem) +#define SiMustWriteLock(sb) AuRwMustWriteLock(&au_sbi(sb)->si_rwsem) +#define SiMustAnyLock(sb) AuRwMustAnyLock(&au_sbi(sb)->si_rwsem) + +/* ---------------------------------------------------------------------- */ + +static inline aufs_bindex_t au_sbend(struct super_block *sb) +{ + SiMustAnyLock(sb); + return au_sbi(sb)->si_bend; +} + +static inline unsigned int au_mntflags(struct super_block *sb) +{ + SiMustAnyLock(sb); + return au_sbi(sb)->si_mntflags; +} + +static inline au_gen_t au_sigen(struct super_block *sb) +{ + SiMustAnyLock(sb); + return au_sbi(sb)->si_generation; +} + +#endif /* __KERNEL__ */ +#endif /* __AUFS_SUPER_H__ */ -- 1.4.4.4 -- To unsubscribe from this list: send the line "unsubscribe linux-fsdevel" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html