| Message ID | 0737603ecc6baf785843d6e91992e6ef202c308c.1647436353.git.naohiro.aota@wdc.com (mailing list archive) |
|---|---|
| State | New, archived |
| Headers | show |
| Series | protect relocation with sb_start_write | expand |
On Wed, Mar 16, 2022 at 10:22:39PM +0900, Naohiro Aota wrote: > Add a function sb_write_started() to return if sb_start_write() is > properly called. It is used in the next commit. > > Also, add the similar functions for sb_start_pagefault() and > sb_start_intwrite(). > > Reviewed-by: Filipe Manana <fdmanana@suse.com> > Signed-off-by: Naohiro Aota <naohiro.aota@wdc.com> > --- > include/linux/fs.h | 20 ++++++++++++++++++++ > 1 file changed, 20 insertions(+) > > diff --git a/include/linux/fs.h b/include/linux/fs.h > index 27746a3da8fd..0c8714d64169 100644 > --- a/include/linux/fs.h > +++ b/include/linux/fs.h > @@ -1732,6 +1732,11 @@ static inline bool __sb_start_write_trylock(struct super_block *sb, int level) > #define __sb_writers_release(sb, lev) \ > percpu_rwsem_release(&(sb)->s_writers.rw_sem[(lev)-1], 1, _THIS_IP_) > > +static inline bool __sb_write_started(struct super_block *sb, int level) > +{ > + return lockdep_is_held_type(sb->s_writers.rw_sem + level - 1, 1); > +} > + > /** > * sb_end_write - drop write access to a superblock > * @sb: the super we wrote to > @@ -1797,6 +1802,11 @@ static inline bool sb_start_write_trylock(struct super_block *sb) > return __sb_start_write_trylock(sb, SB_FREEZE_WRITE); > } > > +static inline bool sb_write_started(struct super_block *sb) > +{ > + return __sb_write_started(sb, SB_FREEZE_WRITE); > +} > + > /** > * sb_start_pagefault - get write access to a superblock from a page fault > * @sb: the super we write to > @@ -1821,6 +1831,11 @@ static inline void sb_start_pagefault(struct super_block *sb) > __sb_start_write(sb, SB_FREEZE_PAGEFAULT); > } > > +static inline bool sb_pagefault_started(struct super_block *sb) > +{ > + return __sb_write_started(sb, SB_FREEZE_PAGEFAULT); > +} > + > /** > * sb_start_intwrite - get write access to a superblock for internal fs purposes > * @sb: the super we write to > @@ -1844,6 +1859,11 @@ static inline bool sb_start_intwrite_trylock(struct super_block *sb) > return __sb_start_write_trylock(sb, SB_FREEZE_FS); > } > > +static inline bool sb_intwrite_started(struct super_block *sb) > +{ > + return __sb_write_started(sb, SB_FREEZE_FS); > +} > + > bool inode_owner_or_capable(struct user_namespace *mnt_userns, > const struct inode *inode); > We should not be adding completely unused code to the VFS APIs. Just rename __sb_write_started() to sb_write_started() and pass SB_FREEZE_WRITE directly from the single debug assert that you've added that needs this check. Cheers, Dave.
On Thu, Mar 17, 2022 at 07:34:20PM +1100, Dave Chinner wrote: > On Wed, Mar 16, 2022 at 10:22:39PM +0900, Naohiro Aota wrote: > > Add a function sb_write_started() to return if sb_start_write() is > > properly called. It is used in the next commit. > > > > Also, add the similar functions for sb_start_pagefault() and > > sb_start_intwrite(). > > > > Reviewed-by: Filipe Manana <fdmanana@suse.com> > > Signed-off-by: Naohiro Aota <naohiro.aota@wdc.com> > > --- > > include/linux/fs.h | 20 ++++++++++++++++++++ > > 1 file changed, 20 insertions(+) > > > > diff --git a/include/linux/fs.h b/include/linux/fs.h > > index 27746a3da8fd..0c8714d64169 100644 > > --- a/include/linux/fs.h > > +++ b/include/linux/fs.h > > @@ -1732,6 +1732,11 @@ static inline bool __sb_start_write_trylock(struct super_block *sb, int level) > > #define __sb_writers_release(sb, lev) \ > > percpu_rwsem_release(&(sb)->s_writers.rw_sem[(lev)-1], 1, _THIS_IP_) > > > > +static inline bool __sb_write_started(struct super_block *sb, int level) > > +{ > > + return lockdep_is_held_type(sb->s_writers.rw_sem + level - 1, 1); > > +} > > + > > /** > > * sb_end_write - drop write access to a superblock > > * @sb: the super we wrote to > > @@ -1797,6 +1802,11 @@ static inline bool sb_start_write_trylock(struct super_block *sb) > > return __sb_start_write_trylock(sb, SB_FREEZE_WRITE); > > } > > > > +static inline bool sb_write_started(struct super_block *sb) > > +{ > > + return __sb_write_started(sb, SB_FREEZE_WRITE); > > +} > > + > > /** > > * sb_start_pagefault - get write access to a superblock from a page fault > > * @sb: the super we write to > > @@ -1821,6 +1831,11 @@ static inline void sb_start_pagefault(struct super_block *sb) > > __sb_start_write(sb, SB_FREEZE_PAGEFAULT); > > } > > > > +static inline bool sb_pagefault_started(struct super_block *sb) > > +{ > > + return __sb_write_started(sb, SB_FREEZE_PAGEFAULT); > > +} > > + > > /** > > * sb_start_intwrite - get write access to a superblock for internal fs purposes > > * @sb: the super we write to > > @@ -1844,6 +1859,11 @@ static inline bool sb_start_intwrite_trylock(struct super_block *sb) > > return __sb_start_write_trylock(sb, SB_FREEZE_FS); > > } > > > > +static inline bool sb_intwrite_started(struct super_block *sb) > > +{ > > + return __sb_write_started(sb, SB_FREEZE_FS); > > +} > > + > > bool inode_owner_or_capable(struct user_namespace *mnt_userns, > > const struct inode *inode); > > > > We should not be adding completely unused code to the VFS APIs. > > Just rename __sb_write_started() to sb_write_started() and pass > SB_FREEZE_WRITE directly from the single debug assert that you've > added that needs this check. Sure, I will drop them in the next version. I just added them for completeness. > Cheers, > > Dave. > -- > Dave Chinner > david@fromorbit.com
diff --git a/include/linux/fs.h b/include/linux/fs.h index 27746a3da8fd..0c8714d64169 100644 --- a/include/linux/fs.h +++ b/include/linux/fs.h @@ -1732,6 +1732,11 @@ static inline bool __sb_start_write_trylock(struct super_block *sb, int level) #define __sb_writers_release(sb, lev) \ percpu_rwsem_release(&(sb)->s_writers.rw_sem[(lev)-1], 1, _THIS_IP_) +static inline bool __sb_write_started(struct super_block *sb, int level) +{ + return lockdep_is_held_type(sb->s_writers.rw_sem + level - 1, 1); +} + /** * sb_end_write - drop write access to a superblock * @sb: the super we wrote to @@ -1797,6 +1802,11 @@ static inline bool sb_start_write_trylock(struct super_block *sb) return __sb_start_write_trylock(sb, SB_FREEZE_WRITE); } +static inline bool sb_write_started(struct super_block *sb) +{ + return __sb_write_started(sb, SB_FREEZE_WRITE); +} + /** * sb_start_pagefault - get write access to a superblock from a page fault * @sb: the super we write to @@ -1821,6 +1831,11 @@ static inline void sb_start_pagefault(struct super_block *sb) __sb_start_write(sb, SB_FREEZE_PAGEFAULT); } +static inline bool sb_pagefault_started(struct super_block *sb) +{ + return __sb_write_started(sb, SB_FREEZE_PAGEFAULT); +} + /** * sb_start_intwrite - get write access to a superblock for internal fs purposes * @sb: the super we write to @@ -1844,6 +1859,11 @@ static inline bool sb_start_intwrite_trylock(struct super_block *sb) return __sb_start_write_trylock(sb, SB_FREEZE_FS); } +static inline bool sb_intwrite_started(struct super_block *sb) +{ + return __sb_write_started(sb, SB_FREEZE_FS); +} + bool inode_owner_or_capable(struct user_namespace *mnt_userns, const struct inode *inode);