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.
Signed-off-by: Li Xi <lixi@xxxxxxx>
---
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
--
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