xfs: add XFS_IOC_FREE_EOFBLOCKS ioctl

The XFS_IOC_FREE_EOFBLOCKS ioctl allows users to invoke an EOFBLOCKS
scan. The xfs_eofblocks structure is defined to support the command
parameters (scan mode).

Signed-off-by: Brian Foster <bfoster@redhat.com>
Reviewed-by: Mark Tinguely <tinguely@sgi.com>
Reviewed-by: Dave Chinner <dchinner@redhat.com>
Signed-off-by: Ben Myers <bpm@sgi.com>

4 files changed, 45 insertions, 4 deletions

diff --git a/fs/xfs/xfs_fs.h b/fs/xfs/xfs_fs.h
index 0948c043443..0cfa30813b1 100644
--- a/fs/xfs/xfs_fs.h
+++ b/fs/xfs/xfs_fs.h
@@ -340,6 +340,22 @@ typedef struct xfs_error_injection {
 
 
 /*
+ * Speculative preallocation trimming.
+ */
+#define XFS_EOFBLOCKS_VERSION           1
+struct xfs_eofblocks {
+        __u32           eof_version;
+        __u32           eof_flags;
+        __u64           pad[15];
+};
+
+/* eof_flags values */
+#define XFS_EOF_FLAGS_SYNC              (1 << 0) /* sync/wait mode scan */
+#define XFS_EOF_FLAGS_VALID     \
+        (XFS_EOF_FLAGS_SYNC)
+
+
+/*
  * The user-level Handle Request interface structure.
  */
 typedef struct xfs_fsop_handlereq {
@@ -457,6 +473,7 @@ typedef struct xfs_handle {
 /*      XFS_IOC_GETBIOSIZE ---- deprecated 47      */
 #define XFS_IOC_GETBMAPX        _IOWR('X', 56, struct getbmap)
 #define XFS_IOC_ZERO_RANGE      _IOW ('X', 57, struct xfs_flock64)
+#define XFS_IOC_FREE_EOFBLOCKS  _IOR ('X', 58, struct xfs_eofblocks)
 
 /*
  * ioctl commands that replace IRIX syssgi()'s
diff --git a/fs/xfs/xfs_icache.c b/fs/xfs/xfs_icache.c
index d115cb44b10..fbb74c71526 100644
--- a/fs/xfs/xfs_icache.c
+++ b/fs/xfs/xfs_icache.c
@@ -1206,11 +1206,15 @@ xfs_inode_free_eofblocks(
 int
 xfs_icache_free_eofblocks(
         struct xfs_mount        *mp,
-        int                     flags)
+        struct xfs_eofblocks    *eofb)
 {
-        ASSERT((flags & ~(SYNC_TRYLOCK|SYNC_WAIT)) == 0);
+        int flags = SYNC_TRYLOCK;
+
+        if (eofb && (eofb->eof_flags & XFS_EOF_FLAGS_SYNC))
+                flags = SYNC_WAIT;
+
         return xfs_inode_ag_iterator_tag(mp, xfs_inode_free_eofblocks, flags,
-                                         NULL, XFS_ICI_EOFBLOCKS_TAG);
+                                         eofb, XFS_ICI_EOFBLOCKS_TAG);
 }
 
 void
diff --git a/fs/xfs/xfs_icache.h b/fs/xfs/xfs_icache.h
index cb6b8d0eee6..4934a77024c 100644
--- a/fs/xfs/xfs_icache.h
+++ b/fs/xfs/xfs_icache.h
@@ -37,7 +37,7 @@ void xfs_inode_set_reclaim_tag(struct xfs_inode *ip);
 
 void xfs_inode_set_eofblocks_tag(struct xfs_inode *ip);
 void xfs_inode_clear_eofblocks_tag(struct xfs_inode *ip);
-int xfs_icache_free_eofblocks(struct xfs_mount *, int);
+int xfs_icache_free_eofblocks(struct xfs_mount *, struct xfs_eofblocks *);
 
 int xfs_sync_inode_grab(struct xfs_inode *ip);
 int xfs_inode_ag_iterator(struct xfs_mount *mp,
diff --git a/fs/xfs/xfs_ioctl.c b/fs/xfs/xfs_ioctl.c
index c1df3c623de..5b20ab0b4f9 100644
--- a/fs/xfs/xfs_ioctl.c
+++ b/fs/xfs/xfs_ioctl.c
@@ -42,6 +42,7 @@
 #include "xfs_inode_item.h"
 #include "xfs_export.h"
 #include "xfs_trace.h"
+#include "xfs_icache.h"
 
 #include <linux/capability.h>
 #include <linux/dcache.h>
@@ -1602,6 +1603,25 @@ xfs_file_ioctl(
                 error = xfs_errortag_clearall(mp, 1);
                 return -error;
 
+        case XFS_IOC_FREE_EOFBLOCKS: {
+                struct xfs_eofblocks eofb;
+
+                if (copy_from_user(&eofb, arg, sizeof(eofb)))
+                        return -XFS_ERROR(EFAULT);
+
+                if (eofb.eof_version != XFS_EOFBLOCKS_VERSION)
+                        return -XFS_ERROR(EINVAL);
+
+                if (eofb.eof_flags & ~XFS_EOF_FLAGS_VALID)
+                        return -XFS_ERROR(EINVAL);
+
+                if (memchr_inv(eofb.pad, 0, sizeof(eofb.pad)))
+                        return -XFS_ERROR(EINVAL);
+
+                error = xfs_icache_free_eofblocks(mp, &eofb);
+                return -error;
+        }
+
         default:
                 return -ENOTTY;
         }