ext4: add FS_IOC_FSSETXATTR/FS_IOC_FSGETXATTR interface support
authorLi Xi <pkuelelixi@gmail.com>
Fri, 8 Jan 2016 21:01:22 +0000 (16:01 -0500)
committerTheodore Ts'o <tytso@mit.edu>
Fri, 8 Jan 2016 21:01:22 +0000 (16:01 -0500)
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@ddn.com>
Signed-off-by: Theodore Ts'o <tytso@mit.edu>
Reviewed-by: Andreas Dilger <adilger@dilger.ca>
Reviewed-by: Jan Kara <jack@suse.cz>
fs/ext4/ext4.h
fs/ext4/ioctl.c

index 96cc151..1c12721 100644 (file)
@@ -381,6 +381,13 @@ 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 |\
@@ -619,6 +626,46 @@ enum {
 #define EXT4_IOC_GET_ENCRYPTION_PWSALT _IOW('f', 20, __u8[16])
 #define EXT4_IOC_GET_ENCRYPTION_POLICY _IOW('f', 21, struct ext4_encryption_policy)
 
+#ifndef FS_IOC_FSGETXATTR
+/* Until the uapi changes get merged for project quota... */
+
+#define FS_IOC_FSGETXATTR              _IOR('X', 31, struct fsxattr)
+#define FS_IOC_FSSETXATTR              _IOW('X', 32, struct fsxattr)
+
+/*
+ * 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 */
+#endif /* !defined(FS_IOC_FSGETXATTR) */
+
+#define EXT4_IOC_FSGETXATTR            FS_IOC_FSGETXATTR
+#define EXT4_IOC_FSSETXATTR            FS_IOC_FSSETXATTR
+
 #if defined(__KERNEL__) && defined(CONFIG_COMPAT)
 /*
  * ioctl commands in 32 bit emulation
index 5e872fd..2b0cb84 100644 (file)
@@ -14,6 +14,7 @@
 #include <linux/mount.h>
 #include <linux/file.h>
 #include <linux/random.h>
+#include <linux/quotaops.h>
 #include <asm/uaccess.h>
 #include "ext4_jbd2.h"
 #include "ext4.h"
@@ -202,6 +203,238 @@ static int uuid_is_zero(__u8 u[16])
        return 1;
 }
 
+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;
+}
+
+#ifdef CONFIG_QUOTA
+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, rc;
+       handle_t *handle;
+       kprojid_t kprojid;
+       struct ext4_iloc iloc;
+       struct ext4_inode *raw_inode;
+
+       if (!EXT4_HAS_RO_COMPAT_FEATURE(sb,
+                       EXT4_FEATURE_RO_COMPAT_PROJECT)) {
+               if (projid != EXT4_DEF_PROJID)
+                       return -EOPNOTSUPP;
+               else
+                       return 0;
+       }
+
+       if (EXT4_INODE_SIZE(sb) <= EXT4_GOOD_OLD_INODE_SIZE)
+               return -EOPNOTSUPP;
+
+       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 out_unlock;
+
+       err = ext4_get_inode_loc(inode, &iloc);
+       if (err)
+               goto out_unlock;
+
+       raw_inode = ext4_raw_inode(&iloc);
+       if (!EXT4_FITS_IN_INODE(raw_inode, ei, i_projid)) {
+               err = -EOVERFLOW;
+               brelse(iloc.bh);
+               goto out_unlock;
+       }
+       brelse(iloc.bh);
+
+       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 out_unlock;
+       }
+
+       err = ext4_reserve_inode_write(handle, inode, &iloc);
+       if (err)
+               goto out_stop;
+
+       if (sb_has_quota_limits_enabled(sb, PRJQUOTA)) {
+               struct dquot *transfer_to[MAXQUOTAS] = { };
+
+               transfer_to[PRJQUOTA] = dqget(sb, make_kqid_projid(kprojid));
+               if (transfer_to[PRJQUOTA]) {
+                       err = __dquot_transfer(inode, transfer_to);
+                       dqput(transfer_to[PRJQUOTA]);
+                       if (err)
+                               goto out_dirty;
+               }
+       }
+       EXT4_I(inode)->i_projid = kprojid;
+       inode->i_ctime = ext4_current_time(inode);
+out_dirty:
+       rc = ext4_mark_iloc_dirty(handle, inode, &iloc);
+       if (!err)
+               err = rc;
+out_stop:
+       ext4_journal_stop(handle);
+out_unlock:
+       mutex_unlock(&inode->i_mutex);
+       mnt_drop_write_file(filp);
+       return err;
+}
+#else
+static int ext4_ioctl_setproject(struct file *filp, __u32 projid)
+{
+       if (projid != EXT4_DEF_PROJID)
+               return -EOPNOTSUPP;
+       return 0;
+}
+#endif
+
+/* 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);
@@ -217,11 +450,7 @@ 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;
@@ -235,89 +464,8 @@ 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;
@@ -689,6 +837,60 @@ encryption_policy_out:
                return -EOPNOTSUPP;
 #endif
        }
+       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;
        }