On Dec 15, 2008, at 2:04 AM, Ankit Jain wrote: > This patch adds ioctls to vfs for compatibility with legacy XFS > pre-allocation ioctls (XFS_IOC_*RESVP*). The implementation > effectively invokes sys_fallocate for the new ioctls.
I don't think we can use sys_fallocate for XFS_IOC_UNRESVSP* commands, which suppose to release currently allocated file blocks. See more comments below. Felix > Note: These legacy ioctls are also implemented by OCFS2. > > There are some things that I'm not sure about: > 1. Should the struct space_resv be exposed to user-space? If not, > then what would be the right place to put it? And the ioctl > definitions? > 2. Should the corresponding ioctls be removed from ocfs2? > > Signed-off-by: Ankit Jain <[email protected]> > --- > fs/ioctl.c | 37 +++++++++++++++++++++++++++ > fs/open.c | 51 ++++++++++++++++++------------------- > include/linux/falloc.h | 19 ++++++++++++++ > include/linux/fs.h | 2 + > 4 files changed, 83 insertions(+), 26 deletions(-) > > diff --git a/fs/ioctl.c b/fs/ioctl.c > index 43e8b2c..5e565c8 100644 > --- a/fs/ioctl.c > +++ b/fs/ioctl.c > @@ -15,6 +15,7 @@ > #include <linux/uaccess.h> > #include <linux/writeback.h> > #include <linux/buffer_head.h> > +#include <linux/falloc.h> > > #include <asm/ioctls.h> > > @@ -346,6 +347,37 @@ EXPORT_SYMBOL(generic_block_fiemap); > > #endif /* CONFIG_BLOCK */ > > +/* > + * This provides compatibility with legacy XFS pre-allocation ioctls > + * which predate the fallocate syscall. > + * > + * Only the l_start, l_len and l_whence fields of the 'struct > space_resv' > + * are used here, rest are ignored. > + */ > +static int ioctl_preallocate(struct file *filp, unsigned long arg) > +{ > + struct inode *inode = filp->f_path.dentry->d_inode; > + struct space_resv sr; > + > + if (copy_from_user(&sr, (struct space_resv __user *) arg, sizeof > (sr))) > + return -EFAULT; > + > + switch (sr.l_whence) { > + case SEEK_SET: > + break; > + case SEEK_CUR: > + sr.l_start += filp->f_pos; > + break; > + case SEEK_END: > + sr.l_start += i_size_read(inode); > + break; > + default: > + return -EINVAL; > + } > + > + return do_fallocate(filp, FALLOC_FL_KEEP_SIZE, sr.l_start, > sr.l_len); > +} > + > static int file_ioctl(struct file *filp, unsigned int cmd, > unsigned long arg) > { > @@ -361,6 +393,11 @@ static int file_ioctl(struct file *filp, > unsigned int cmd, > return put_user(inode->i_sb->s_blocksize, p); > case FIONREAD: > return put_user(i_size_read(inode) - filp->f_pos, p); > + case F_IOC_RESVSP: > + case F_IOC_RESVSP64: > + case F_IOC_UNRESVSP: > + case F_IOC_UNRESVSP64: > + return ioctl_preallocate(filp, arg); At this point the original command 'cmd' is dropped, and ioctl_preallocate() assumes F_IOC_RESVSP*. Indeed, in the following path ioctl_preallocate do_fallocate .fallocate/xfs_vn_fallocate xfs_change_file_space(XFS_IOC_RESVSP) UNRESVSP is never considered. > } > > return vfs_ioctl(filp, cmd, arg); > diff --git a/fs/open.c b/fs/open.c > index 83cdb9d..0703bcb 100644 > --- a/fs/open.c > +++ b/fs/open.c > @@ -360,62 +360,61 @@ asmlinkage long sys_ftruncate64(unsigned int > fd, loff_t length) > } > #endif > > -asmlinkage long sys_fallocate(int fd, int mode, loff_t offset, > loff_t len) > +long do_fallocate(struct file *file, int mode, loff_t offset, > loff_t len) > { > - struct file *file; > struct inode *inode; > - long ret = -EINVAL; > + long ret; > > if (offset < 0 || len <= 0) > - goto out; > + return -EINVAL; > > /* Return error if mode is not supported */ > - ret = -EOPNOTSUPP; > if (mode && !(mode & FALLOC_FL_KEEP_SIZE)) > - goto out; > + return -EOPNOTSUPP; > > - ret = -EBADF; > - file = fget(fd); > - if (!file) > - goto out; > - if (!(file->f_mode & FMODE_WRITE)) > - goto out_fput; > + if (!file || !(file->f_mode & FMODE_WRITE)) > + return -EBADF; > /* > * Revalidate the write permissions, in case security policy has > * changed since the files were opened. > */ > ret = security_file_permission(file, MAY_WRITE); > if (ret) > - goto out_fput; > + return ret; > > inode = file->f_path.dentry->d_inode; > - > - ret = -ESPIPE; > if (S_ISFIFO(inode->i_mode)) > - goto out_fput; > + return -ESPIPE; > > - ret = -ENODEV; > /* > * Let individual file system decide if it supports preallocation > * for directories or not. > */ > if (!S_ISREG(inode->i_mode) && !S_ISDIR(inode->i_mode)) > - goto out_fput; > + return -ENODEV; > > - ret = -EFBIG; > /* Check for wrap through zero too */ > if (((offset + len) > inode->i_sb->s_maxbytes) || ((offset + len) > < 0)) > - goto out_fput; > + return -EFBIG; > > if (inode->i_op && inode->i_op->fallocate) > - ret = inode->i_op->fallocate(inode, mode, offset, len); > + return inode->i_op->fallocate(inode, mode, offset, len); > else > - ret = -EOPNOTSUPP; > + return -EOPNOTSUPP; > +} > > -out_fput: > - fput(file); > -out: > - return ret; > +asmlinkage long sys_fallocate(int fd, int mode, loff_t offset, > loff_t len) > +{ > + struct file *file; > + int error = -EBADF; > + > + file = fget(fd); > + if (file) { > + error = do_fallocate(file, mode, offset, len); > + fput(file); > + } > + > + return error; > } > > /* > diff --git a/include/linux/falloc.h b/include/linux/falloc.h > index 8e912ab..4f2a727 100644 > --- a/include/linux/falloc.h > +++ b/include/linux/falloc.h > @@ -3,4 +3,23 @@ > > #define FALLOC_FL_KEEP_SIZE 0x01 /* default is extend size */ > > +/* > + * Space reservation / allocation ioctls and argument structure > + * are designed to be compatible with the legacy XFS ioctls. > + */ > +struct space_resv { > + __s16 l_type; > + __s16 l_whence; > + __s64 l_start; > + __s64 l_len; /* len == 0 means until end of file */ > + __s32 l_sysid; > + __u32 l_pid; > + __s32 l_pad[4]; /* reserve area */ > +}; > + > +#define F_IOC_RESVSP _IOW('X', 40, struct space_resv) > +#define F_IOC_UNRESVSP _IOW('X', 41, struct space_resv) > +#define F_IOC_RESVSP64 _IOW('X', 42, struct space_resv) > +#define F_IOC_UNRESVSP64 _IOW('X', 43, struct space_resv) > + > #endif /* _FALLOC_H_ */ > diff --git a/include/linux/fs.h b/include/linux/fs.h > index 4a853ef..b1d8f12 100644 > --- a/include/linux/fs.h > +++ b/include/linux/fs.h > @@ -1671,6 +1671,8 @@ static inline int break_lease(struct inode > *inode, unsigned int mode) > > extern int do_truncate(struct dentry *, loff_t start, unsigned int > time_attrs, > struct file *filp); > +extern long do_fallocate(struct file *file, int mode, loff_t offset, > + loff_t len); > extern long do_sys_open(int dfd, const char __user *filename, int > flags, > int mode); > extern struct file *filp_open(const char *, int, int); > -- > To unsubscribe from this list: send the line "unsubscribe linux- > fsdevel" in > the body of a message to [email protected] > More majordomo info at http://vger.kernel.org/majordomo-info.html _______________________________________________ Ocfs2-devel mailing list [email protected] http://oss.oracle.com/mailman/listinfo/ocfs2-devel
