by Jan Kara

[permalink] [raw]

Subject: Re: [v13 4/5] ext4: adds FS_IOC_FSSETXATTR/FS_IOC_FSGETXATTR interface support

On Mon 20-04-15 10:39:47, Li Xi wrote:
> This patch adds FS_IOC_FSSETXATTR/FS_IOC_FSGETXATTR ioctl interface
> support for ext4. The interface is kept consistent with
> XFS_IOC_FSGETXATTR/XFS_IOC_FSGETXATTR.
Thanks for the patch! Besides what Andreas wrote, the patch looks good to
me.

Honza
>
> Signed-off-by: Li Xi <[email protected]>
> ---
> fs/ext4/ext4.h | 9 ++
> fs/ext4/ioctl.c | 364 +++++++++++++++++++++++++++++++++++-----------
> fs/xfs/xfs_fs.h | 47 +++----
> include/uapi/linux/fs.h | 32 ++++
> 4 files changed, 335 insertions(+), 117 deletions(-)
>
> diff --git a/fs/ext4/ext4.h b/fs/ext4/ext4.h
> index a7acf10..2d5a097 100644
> --- a/fs/ext4/ext4.h
> +++ b/fs/ext4/ext4.h
> @@ -384,6 +384,13 @@ struct flex_groups {
> #define EXT4_FL_USER_VISIBLE 0x304BDFFF /* User visible flags */
> #define EXT4_FL_USER_MODIFIABLE 0x204380FF /* User modifiable flags */
>
> +#define EXT4_FL_XFLAG_VISIBLE (EXT4_SYNC_FL | \
> + EXT4_IMMUTABLE_FL | \
> + EXT4_APPEND_FL | \
> + EXT4_NODUMP_FL | \
> + EXT4_NOATIME_FL | \
> + EXT4_PROJINHERIT_FL)
> +
> /* Flags that should be inherited by new inodes from their parent. */
> #define EXT4_FL_INHERITED (EXT4_SECRM_FL | EXT4_UNRM_FL | EXT4_COMPR_FL |\
> EXT4_SYNC_FL | EXT4_NODUMP_FL | EXT4_NOATIME_FL |\
> @@ -606,6 +613,8 @@ enum {
> #define EXT4_IOC_RESIZE_FS _IOW('f', 16, __u64)
> #define EXT4_IOC_SWAP_BOOT _IO('f', 17)
> #define EXT4_IOC_PRECACHE_EXTENTS _IO('f', 18)
> +#define EXT4_IOC_FSGETXATTR FS_IOC_FSGETXATTR
> +#define EXT4_IOC_FSSETXATTR FS_IOC_FSSETXATTR
>
> #if defined(__KERNEL__) && defined(CONFIG_COMPAT)
> /*
> diff --git a/fs/ext4/ioctl.c b/fs/ext4/ioctl.c
> index f58a0d1..27e50a8 100644
> --- a/fs/ext4/ioctl.c
> +++ b/fs/ext4/ioctl.c
> @@ -14,6 +14,8 @@
> #include <linux/compat.h>
> #include <linux/mount.h>
> #include <linux/file.h>
> +#include <linux/quotaops.h>
> +#include <linux/quota.h>
> #include <asm/uaccess.h>
> #include "ext4_jbd2.h"
> #include "ext4.h"
> @@ -196,6 +198,225 @@ journal_err_out:
> return err;
> }
>
> +static int ext4_ioctl_setflags(struct inode *inode,
> + unsigned int flags)
> +{
> + struct ext4_inode_info *ei = EXT4_I(inode);
> + handle_t *handle = NULL;
> + int err = EPERM, migrate = 0;
> + struct ext4_iloc iloc;
> + unsigned int oldflags, mask, i;
> + unsigned int jflag;
> +
> + /* Is it quota file? Do not allow user to mess with it */
> + if (IS_NOQUOTA(inode))
> + goto flags_out;
> +
> + oldflags = ei->i_flags;
> +
> + /* The JOURNAL_DATA flag is modifiable only by root */
> + jflag = flags & EXT4_JOURNAL_DATA_FL;
> +
> + /*
> + * The IMMUTABLE and APPEND_ONLY flags can only be changed by
> + * the relevant capability.
> + *
> + * This test looks nicer. Thanks to Pauline Middelink
> + */
> + if ((flags ^ oldflags) & (EXT4_APPEND_FL | EXT4_IMMUTABLE_FL)) {
> + if (!capable(CAP_LINUX_IMMUTABLE))
> + goto flags_out;
> + }
> +
> + /*
> + * The JOURNAL_DATA flag can only be changed by
> + * the relevant capability.
> + */
> + if ((jflag ^ oldflags) & (EXT4_JOURNAL_DATA_FL)) {
> + if (!capable(CAP_SYS_RESOURCE))
> + goto flags_out;
> + }
> + if ((flags ^ oldflags) & EXT4_EXTENTS_FL)
> + migrate = 1;
> +
> + if (flags & EXT4_EOFBLOCKS_FL) {
> + /* we don't support adding EOFBLOCKS flag */
> + if (!(oldflags & EXT4_EOFBLOCKS_FL)) {
> + err = -EOPNOTSUPP;
> + goto flags_out;
> + }
> + } else if (oldflags & EXT4_EOFBLOCKS_FL)
> + ext4_truncate(inode);
> +
> + handle = ext4_journal_start(inode, EXT4_HT_INODE, 1);
> + if (IS_ERR(handle)) {
> + err = PTR_ERR(handle);
> + goto flags_out;
> + }
> + if (IS_SYNC(inode))
> + ext4_handle_sync(handle);
> + err = ext4_reserve_inode_write(handle, inode, &iloc);
> + if (err)
> + goto flags_err;
> +
> + for (i = 0, mask = 1; i < 32; i++, mask <<= 1) {
> + if (!(mask & EXT4_FL_USER_MODIFIABLE))
> + continue;
> + if (mask & flags)
> + ext4_set_inode_flag(inode, i);
> + else
> + ext4_clear_inode_flag(inode, i);
> + }
> +
> + ext4_set_inode_flags(inode);
> + inode->i_ctime = ext4_current_time(inode);
> +
> + err = ext4_mark_iloc_dirty(handle, inode, &iloc);
> +flags_err:
> + ext4_journal_stop(handle);
> + if (err)
> + goto flags_out;
> +
> + if ((jflag ^ oldflags) & (EXT4_JOURNAL_DATA_FL))
> + err = ext4_change_inode_journal_flag(inode, jflag);
> + if (err)
> + goto flags_out;
> + if (migrate) {
> + if (flags & EXT4_EXTENTS_FL)
> + err = ext4_ext_migrate(inode);
> + else
> + err = ext4_ind_migrate(inode);
> + }
> +
> +flags_out:
> + return err;
> +}
> +
> +static int ext4_ioctl_setproject(struct file *filp, __u32 projid)
> +{
> + struct inode *inode = file_inode(filp);
> + struct super_block *sb = inode->i_sb;
> + struct ext4_inode_info *ei = EXT4_I(inode);
> + int err;
> + handle_t *handle;
> + kprojid_t kprojid;
> + struct ext4_iloc iloc;
> + struct ext4_inode *raw_inode;
> +
> + struct dquot *transfer_to[EXT4_MAXQUOTAS] = { };
> +
> + if (!EXT4_HAS_RO_COMPAT_FEATURE(sb,
> + EXT4_FEATURE_RO_COMPAT_PROJECT)) {
> + BUG_ON(__kprojid_val(EXT4_I(inode)->i_projid)
> + != EXT4_DEF_PROJID);
> + if (projid != EXT4_DEF_PROJID)
> + return -EOPNOTSUPP;
> + else
> + return 0;
> + }
> +
> + kprojid = make_kprojid(&init_user_ns, (projid_t)projid);
> +
> + if (projid_eq(kprojid, EXT4_I(inode)->i_projid))
> + return 0;
> +
> + err = mnt_want_write_file(filp);
> + if (err)
> + return err;
> +
> + err = -EPERM;
> + mutex_lock(&inode->i_mutex);
> + /* Is it quota file? Do not allow user to mess with it */
> + if (IS_NOQUOTA(inode))
> + goto project_out;
> +
> + dquot_initialize(inode);
> +
> + handle = ext4_journal_start(inode, EXT4_HT_QUOTA,
> + EXT4_QUOTA_INIT_BLOCKS(sb) +
> + EXT4_QUOTA_DEL_BLOCKS(sb) + 3);
> + if (IS_ERR(handle)) {
> + err = PTR_ERR(handle);
> + goto project_out;
> + }
> +
> + err = ext4_reserve_inode_write(handle, inode, &iloc);
> + if (err)
> + goto project_stop;
> +
> + raw_inode = ext4_raw_inode(&iloc);
> + if (EXT4_INODE_SIZE(sb) <= EXT4_GOOD_OLD_INODE_SIZE) {
> + err = -EOPNOTSUPP;
> + goto project_stop;
> + }
> +
> + if (!EXT4_FITS_IN_INODE(raw_inode, ei, i_projid)) {
> + err = -EOVERFLOW;
> + goto project_stop;
> + }
> +
> + transfer_to[PRJQUOTA] = dqget(sb, make_kqid_projid(kprojid));
> + if (!transfer_to[PRJQUOTA])
> + goto project_set;
> +
> + err = __dquot_transfer(inode, transfer_to);
> + dqput(transfer_to[PRJQUOTA]);
> + if (err)
> + goto project_stop;
> +
> +project_set:
> + EXT4_I(inode)->i_projid = kprojid;
> + inode->i_ctime = ext4_current_time(inode);
> + err = ext4_mark_iloc_dirty(handle, inode, &iloc);
> +project_stop:
> + ext4_journal_stop(handle);
> +project_out:
> + mutex_unlock(&inode->i_mutex);
> + mnt_drop_write_file(filp);
> + return err;
> +}
> +
> +/* Transfer internal flags to xflags */
> +static inline __u32 ext4_iflags_to_xflags(unsigned long iflags)
> +{
> + __u32 xflags = 0;
> +
> + if (iflags & EXT4_SYNC_FL)
> + xflags |= FS_XFLAG_SYNC;
> + if (iflags & EXT4_IMMUTABLE_FL)
> + xflags |= FS_XFLAG_IMMUTABLE;
> + if (iflags & EXT4_APPEND_FL)
> + xflags |= FS_XFLAG_APPEND;
> + if (iflags & EXT4_NODUMP_FL)
> + xflags |= FS_XFLAG_NODUMP;
> + if (iflags & EXT4_NOATIME_FL)
> + xflags |= FS_XFLAG_NOATIME;
> + if (iflags & EXT4_PROJINHERIT_FL)
> + xflags |= FS_XFLAG_PROJINHERIT;
> + return xflags;
> +}
> +
> +/* Transfer xflags flags to internal */
> +static inline unsigned long ext4_xflags_to_iflags(__u32 xflags)
> +{
> + unsigned long iflags = 0;
> +
> + if (xflags & FS_XFLAG_SYNC)
> + iflags |= EXT4_SYNC_FL;
> + if (xflags & FS_XFLAG_IMMUTABLE)
> + iflags |= EXT4_IMMUTABLE_FL;
> + if (xflags & FS_XFLAG_APPEND)
> + iflags |= EXT4_APPEND_FL;
> + if (xflags & FS_XFLAG_NODUMP)
> + iflags |= EXT4_NODUMP_FL;
> + if (xflags & FS_XFLAG_NOATIME)
> + iflags |= EXT4_NOATIME_FL;
> + if (xflags & FS_XFLAG_PROJINHERIT)
> + iflags |= EXT4_PROJINHERIT_FL;
> +
> + return iflags;
> +}
> +
> long ext4_ioctl(struct file *filp, unsigned int cmd, unsigned long arg)
> {
> struct inode *inode = file_inode(filp);
> @@ -211,11 +432,7 @@ long ext4_ioctl(struct file *filp, unsigned int cmd, unsigned long arg)
> flags = ei->i_flags & EXT4_FL_USER_VISIBLE;
> return put_user(flags, (int __user *) arg);
> case EXT4_IOC_SETFLAGS: {
> - handle_t *handle = NULL;
> - int err, migrate = 0;
> - struct ext4_iloc iloc;
> - unsigned int oldflags, mask, i;
> - unsigned int jflag;
> + int err;
>
> if (!inode_owner_or_capable(inode))
> return -EACCES;
> @@ -229,89 +446,8 @@ long ext4_ioctl(struct file *filp, unsigned int cmd, unsigned long arg)
>
> flags = ext4_mask_flags(inode->i_mode, flags);
>
> - err = -EPERM;
> mutex_lock(&inode->i_mutex);
> - /* Is it quota file? Do not allow user to mess with it */
> - if (IS_NOQUOTA(inode))
> - goto flags_out;
> -
> - oldflags = ei->i_flags;
> -
> - /* The JOURNAL_DATA flag is modifiable only by root */
> - jflag = flags & EXT4_JOURNAL_DATA_FL;
> -
> - /*
> - * The IMMUTABLE and APPEND_ONLY flags can only be changed by
> - * the relevant capability.
> - *
> - * This test looks nicer. Thanks to Pauline Middelink
> - */
> - if ((flags ^ oldflags) & (EXT4_APPEND_FL | EXT4_IMMUTABLE_FL)) {
> - if (!capable(CAP_LINUX_IMMUTABLE))
> - goto flags_out;
> - }
> -
> - /*
> - * The JOURNAL_DATA flag can only be changed by
> - * the relevant capability.
> - */
> - if ((jflag ^ oldflags) & (EXT4_JOURNAL_DATA_FL)) {
> - if (!capable(CAP_SYS_RESOURCE))
> - goto flags_out;
> - }
> - if ((flags ^ oldflags) & EXT4_EXTENTS_FL)
> - migrate = 1;
> -
> - if (flags & EXT4_EOFBLOCKS_FL) {
> - /* we don't support adding EOFBLOCKS flag */
> - if (!(oldflags & EXT4_EOFBLOCKS_FL)) {
> - err = -EOPNOTSUPP;
> - goto flags_out;
> - }
> - } else if (oldflags & EXT4_EOFBLOCKS_FL)
> - ext4_truncate(inode);
> -
> - handle = ext4_journal_start(inode, EXT4_HT_INODE, 1);
> - if (IS_ERR(handle)) {
> - err = PTR_ERR(handle);
> - goto flags_out;
> - }
> - if (IS_SYNC(inode))
> - ext4_handle_sync(handle);
> - err = ext4_reserve_inode_write(handle, inode, &iloc);
> - if (err)
> - goto flags_err;
> -
> - for (i = 0, mask = 1; i < 32; i++, mask <<= 1) {
> - if (!(mask & EXT4_FL_USER_MODIFIABLE))
> - continue;
> - if (mask & flags)
> - ext4_set_inode_flag(inode, i);
> - else
> - ext4_clear_inode_flag(inode, i);
> - }
> -
> - ext4_set_inode_flags(inode);
> - inode->i_ctime = ext4_current_time(inode);
> -
> - err = ext4_mark_iloc_dirty(handle, inode, &iloc);
> -flags_err:
> - ext4_journal_stop(handle);
> - if (err)
> - goto flags_out;
> -
> - if ((jflag ^ oldflags) & (EXT4_JOURNAL_DATA_FL))
> - err = ext4_change_inode_journal_flag(inode, jflag);
> - if (err)
> - goto flags_out;
> - if (migrate) {
> - if (flags & EXT4_EXTENTS_FL)
> - err = ext4_ext_migrate(inode);
> - else
> - err = ext4_ind_migrate(inode);
> - }
> -
> -flags_out:
> + err = ext4_ioctl_setflags(inode, flags);
> mutex_unlock(&inode->i_mutex);
> mnt_drop_write_file(filp);
> return err;
> @@ -615,7 +751,61 @@ resizefs_out:
> }
> case EXT4_IOC_PRECACHE_EXTENTS:
> return ext4_ext_precache(inode);
> + case EXT4_IOC_FSGETXATTR:
> + {
> + struct fsxattr fa;
> +
> + memset(&fa, 0, sizeof(struct fsxattr));
>
> + ext4_get_inode_flags(ei);
> + fa.fsx_xflags = ext4_iflags_to_xflags(ei->i_flags & EXT4_FL_USER_VISIBLE);
> +
> + if (EXT4_HAS_RO_COMPAT_FEATURE(inode->i_sb,
> + EXT4_FEATURE_RO_COMPAT_PROJECT)) {
> + fa.fsx_projid = (__u32)from_kprojid(&init_user_ns,
> + EXT4_I(inode)->i_projid);
> + }
> +
> + if (copy_to_user((struct fsxattr __user *)arg,
> + &fa, sizeof(fa)))
> + return -EFAULT;
> + return 0;
> + }
> + case EXT4_IOC_FSSETXATTR:
> + {
> + struct fsxattr fa;
> + int err;
> +
> + if (copy_from_user(&fa, (struct fsxattr __user *)arg,
> + sizeof(fa)))
> + return -EFAULT;
> +
> + /* Make sure caller has proper permission */
> + if (!inode_owner_or_capable(inode))
> + return -EACCES;
> +
> + err = mnt_want_write_file(filp);
> + if (err)
> + return err;
> +
> + flags = ext4_xflags_to_iflags(fa.fsx_xflags);
> + flags = ext4_mask_flags(inode->i_mode, flags);
> +
> + mutex_lock(&inode->i_mutex);
> + flags = (ei->i_flags & ~EXT4_FL_XFLAG_VISIBLE) |
> + (flags & EXT4_FL_XFLAG_VISIBLE);
> + err = ext4_ioctl_setflags(inode, flags);
> + mutex_unlock(&inode->i_mutex);
> + mnt_drop_write_file(filp);
> + if (err)
> + return err;
> +
> + err = ext4_ioctl_setproject(filp, fa.fsx_projid);
> + if (err)
> + return err;
> +
> + return 0;
> + }
> default:
> return -ENOTTY;
> }
> diff --git a/fs/xfs/xfs_fs.h b/fs/xfs/xfs_fs.h
> index 18dc721..64c7ae6 100644
> --- a/fs/xfs/xfs_fs.h
> +++ b/fs/xfs/xfs_fs.h
> @@ -36,38 +36,25 @@ struct dioattr {
> #endif
>
> /*
> - * Structure for XFS_IOC_FSGETXATTR[A] and XFS_IOC_FSSETXATTR.
> - */
> -#ifndef HAVE_FSXATTR
> -struct fsxattr {
> - __u32 fsx_xflags; /* xflags field value (get/set) */
> - __u32 fsx_extsize; /* extsize field value (get/set)*/
> - __u32 fsx_nextents; /* nextents field value (get) */
> - __u32 fsx_projid; /* project identifier (get/set) */
> - unsigned char fsx_pad[12];
> -};
> -#endif
> -
> -/*
> * Flags for the bs_xflags/fsx_xflags field
> * There should be a one-to-one correspondence between these flags and the
> * XFS_DIFLAG_s.
> */
> -#define XFS_XFLAG_REALTIME 0x00000001 /* data in realtime volume */
> -#define XFS_XFLAG_PREALLOC 0x00000002 /* preallocated file extents */
> -#define XFS_XFLAG_IMMUTABLE 0x00000008 /* file cannot be modified */
> -#define XFS_XFLAG_APPEND 0x00000010 /* all writes append */
> -#define XFS_XFLAG_SYNC 0x00000020 /* all writes synchronous */
> -#define XFS_XFLAG_NOATIME 0x00000040 /* do not update access time */
> -#define XFS_XFLAG_NODUMP 0x00000080 /* do not include in backups */
> -#define XFS_XFLAG_RTINHERIT 0x00000100 /* create with rt bit set */
> -#define XFS_XFLAG_PROJINHERIT 0x00000200 /* create with parents projid */
> -#define XFS_XFLAG_NOSYMLINKS 0x00000400 /* disallow symlink creation */
> -#define XFS_XFLAG_EXTSIZE 0x00000800 /* extent size allocator hint */
> -#define XFS_XFLAG_EXTSZINHERIT 0x00001000 /* inherit inode extent size */
> -#define XFS_XFLAG_NODEFRAG 0x00002000 /* do not defragment */
> -#define XFS_XFLAG_FILESTREAM 0x00004000 /* use filestream allocator */
> -#define XFS_XFLAG_HASATTR 0x80000000 /* no DIFLAG for this */
> +#define XFS_XFLAG_REALTIME FS_XFLAG_REALTIME /* data in realtime volume */
> +#define XFS_XFLAG_PREALLOC FS_XFLAG_PREALLOC /* preallocated file extents */
> +#define XFS_XFLAG_IMMUTABLE FS_XFLAG_IMMUTABLE /* file cannot be modified */
> +#define XFS_XFLAG_APPEND FS_XFLAG_APPEND /* all writes append */
> +#define XFS_XFLAG_SYNC FS_XFLAG_SYNC /* all writes synchronous */
> +#define XFS_XFLAG_NOATIME FS_XFLAG_NOATIME /* do not update access time */
> +#define XFS_XFLAG_NODUMP FS_XFLAG_NODUMP /* do not include in backups */
> +#define XFS_XFLAG_RTINHERIT FS_XFLAG_RTINHERIT /* create with rt bit set */
> +#define XFS_XFLAG_PROJINHERIT FS_XFLAG_PROJINHERIT /* create with parents projid */
> +#define XFS_XFLAG_NOSYMLINKS FS_XFLAG_NOSYMLINKS /* disallow symlink creation */
> +#define XFS_XFLAG_EXTSIZE FS_XFLAG_EXTSIZE /* extent size allocator hint */
> +#define XFS_XFLAG_EXTSZINHERIT FS_XFLAG_EXTSZINHERIT /* inherit inode extent size */
> +#define XFS_XFLAG_NODEFRAG FS_XFLAG_NODEFRAG /* do not defragment */
> +#define XFS_XFLAG_FILESTREAM FS_XFLAG_FILESTREAM /* use filestream allocator */
> +#define XFS_XFLAG_HASATTR FS_XFLAG_HASATTR /* no DIFLAG for this */
>
> /*
> * Structure for XFS_IOC_GETBMAP.
> @@ -503,8 +490,8 @@ typedef struct xfs_swapext
> #define XFS_IOC_ALLOCSP _IOW ('X', 10, struct xfs_flock64)
> #define XFS_IOC_FREESP _IOW ('X', 11, struct xfs_flock64)
> #define XFS_IOC_DIOINFO _IOR ('X', 30, struct dioattr)
> -#define XFS_IOC_FSGETXATTR _IOR ('X', 31, struct fsxattr)
> -#define XFS_IOC_FSSETXATTR _IOW ('X', 32, struct fsxattr)
> +#define XFS_IOC_FSGETXATTR FS_IOC_FSGETXATTR
> +#define XFS_IOC_FSSETXATTR FS_IOC_FSSETXATTR
> #define XFS_IOC_ALLOCSP64 _IOW ('X', 36, struct xfs_flock64)
> #define XFS_IOC_FREESP64 _IOW ('X', 37, struct xfs_flock64)
> #define XFS_IOC_GETBMAP _IOWR('X', 38, struct getbmap)
> diff --git a/include/uapi/linux/fs.h b/include/uapi/linux/fs.h
> index fcbf647..69dda62 100644
> --- a/include/uapi/linux/fs.h
> +++ b/include/uapi/linux/fs.h
> @@ -58,6 +58,36 @@ struct inodes_stat_t {
> long dummy[5]; /* padding for sysctl ABI compatibility */
> };
>
> +/*
> + * Structure for FS_IOC_FSGETXATTR and FS_IOC_FSSETXATTR.
> + */
> +struct fsxattr {
> + __u32 fsx_xflags; /* xflags field value (get/set) */
> + __u32 fsx_extsize; /* extsize field value (get/set)*/
> + __u32 fsx_nextents; /* nextents field value (get) */
> + __u32 fsx_projid; /* project identifier (get/set) */
> + unsigned char fsx_pad[12];
> +};
> +
> +/*
> + * Flags for the fsx_xflags field
> + */
> +#define FS_XFLAG_REALTIME 0x00000001 /* data in realtime volume */
> +#define FS_XFLAG_PREALLOC 0x00000002 /* preallocated file extents */
> +#define FS_XFLAG_IMMUTABLE 0x00000008 /* file cannot be modified */
> +#define FS_XFLAG_APPEND 0x00000010 /* all writes append */
> +#define FS_XFLAG_SYNC 0x00000020 /* all writes synchronous */
> +#define FS_XFLAG_NOATIME 0x00000040 /* do not update access time */
> +#define FS_XFLAG_NODUMP 0x00000080 /* do not include in backups */
> +#define FS_XFLAG_RTINHERIT 0x00000100 /* create with rt bit set */
> +#define FS_XFLAG_PROJINHERIT 0x00000200 /* create with parents projid */
> +#define FS_XFLAG_NOSYMLINKS 0x00000400 /* disallow symlink creation */
> +#define FS_XFLAG_EXTSIZE 0x00000800 /* extent size allocator hint */
> +#define FS_XFLAG_EXTSZINHERIT 0x00001000 /* inherit inode extent size */
> +#define FS_XFLAG_NODEFRAG 0x00002000 /* do not defragment */
> +#define FS_XFLAG_FILESTREAM 0x00004000 /* use filestream allocator */
> +#define FS_XFLAG_HASATTR 0x80000000 /* no DIFLAG for this */
> +
>
> #define NR_FILE 8192 /* this can well be larger on a larger system */
>
> @@ -163,6 +193,8 @@ struct inodes_stat_t {
> #define FS_IOC_GETVERSION _IOR('v', 1, long)
> #define FS_IOC_SETVERSION _IOW('v', 2, long)
> #define FS_IOC_FIEMAP _IOWR('f', 11, struct fiemap)
> +#define FS_IOC_FSGETXATTR _IOR('X', 31, struct fsxattr)
> +#define FS_IOC_FSSETXATTR _IOW('X', 32, struct fsxattr)
> #define FS_IOC32_GETFLAGS _IOR('f', 1, int)
> #define FS_IOC32_SETFLAGS _IOW('f', 2, int)
> #define FS_IOC32_GETVERSION _IOR('v', 1, int)
> --
> 1.7.1
>
--
Jan Kara <[email protected]>
SUSE Labs, CR

2015-04-22 18:52:21

by Li Xi

[permalink] [raw]

Subject: Re: [v13 3/5] ext4: adds project quota support

I agree that we need to deciede which inode numbers to use for special
system file. Anyway, I will use the first way in the next version of
patch.

On Tue, Apr 21, 2015 at 8:35 PM, Jan Kara <[email protected]> wrote:
> On Mon 20-04-15 17:27:20, Andreas Dilger wrote:
>> On Apr 19, 2015, at 7:39 PM, Li Xi <[email protected]> wrote:
> ...
>> > diff --git a/fs/ext4/ext4.h b/fs/ext4/ext4.h
>> > index 1446c4f..a7acf10 100644
>> > --- a/fs/ext4/ext4.h
>> > +++ b/fs/ext4/ext4.h
>> > @@ -1169,7 +1169,8 @@ struct ext4_super_block {
>> > __le32 s_overhead_clusters; /* overhead blocks/clusters in fs */
>> > __le32 s_backup_bgs[2]; /* groups with sparse_super2 SBs */
>> > __u8 s_encrypt_algos[4]; /* Encryption algorithms in use */
>> > - __le32 s_reserved[105]; /* Padding to the end of the block */
>> > + __le32 s_prj_quota_inum; /* inode for tracking project quota */
>> > + __le32 s_reserved[104]; /* Padding to the end of the block */
>> > __le32 s_checksum; /* crc32c(superblock) */
>> > };
>> >
>> > @@ -1184,7 +1185,7 @@ struct ext4_super_block {
>> > #define EXT4_MF_FS_ABORTED 0x0002 /* Fatal error detected */
>> >
>> > /* Number of quota types we support */
>> > -#define EXT4_MAXQUOTAS 2
>> > +#define EXT4_MAXQUOTAS 3
>> >
>> > /*
>> > * fourth extended-fs super-block data in memory
>> > @@ -1376,6 +1377,7 @@ static inline int ext4_valid_inum(struct super_block *sb, unsigned long ino)
>> > ino == EXT4_BOOT_LOADER_INO ||
>> > ino == EXT4_JOURNAL_INO ||
>> > ino == EXT4_RESIZE_INO ||
>> > + ino == le32_to_cpu(EXT4_SB(sb)->s_es->s_prj_quota_inum) ||
>>
>> This extra check isn't needed, since s_proj_quota_inum will be a regular
>> inode number and handled by the checks below.
> So I think this needs a final decision from Ted how we handle new system
> files and use it consistently among all features - project quotas, orphan
> file, etc. Ted, can you share your thoughts please? Options are:
>
> 1) We allocate inodes from normal inode pool and just store their inode
> numbers in superblock.
> + no need to increase number of special inodes
> - slightly less robust since inode can be anywhere
> - needs special treatment from fsck to know inode isn't just some lost inode
> - consumes space in sb for inode numbers
>
> 2) Like 1) but also create special "system" directory and attach system
> inodes there
> + fsck just needs to know about the system directory, not about every
> special file
> + no wasted space in sb for every special inode
> - more code in kernel to implement this
> - even less robust than 1) - when system directory gets corrupt, we are in
> trouble
>
> 3) Increase number of special inodes
> + consistent with what we did upto now
> + somewhat more robust since inode is in fixed place
> - tune2fs needs to do quite some work to reserve more inodes
> - wastes unused special inodes
>
> Honza
> --
> Jan Kara <[email protected]>
> SUSE Labs, CR