Reserve the FIEMAP_EXTENT_DATA_COMPRESSED flag to allow reporting
extents with physical length different than logical length. This
also sets the FIEMAP_EXTENT_ENCODED flag to indicate that the data
cannot be accessed directly. This adds a new fe_phys_length field
to struct fiemap_extent which specifies the physical extent length
in bytes when DATA_COMPRESSED is set. Linux 3.14 and later kernels
will fill out the fe_phys_length field, but in older kernels the
contents are undefined (though typically zero).
Reserve the FIEMAP_EXTENT_NET flag, which indicates that the data
is on a network filesystem. This also sets FIEMAP_EXTENT_ENCODED
flag to indicate the data cannot be accessed directly.
Print out these flags in filefrag if detected.
Signed-off-by: Andreas Dilger <adilger@xxxxxxxxx>
---
lib/ext2fs/fiemap.h | 14 ++++++++++----
misc/filefrag.c | 2 ++
2 files changed, 12 insertions(+), 4 deletions(-)
diff --git a/lib/ext2fs/fiemap.h b/lib/ext2fs/fiemap.h
index 30bf555..df973da 100644
--- a/lib/ext2fs/fiemap.h
+++ b/lib/ext2fs/fiemap.h
@@ -17,15 +17,17 @@ struct fiemap_extent {
__u64 fe_physical; /* physical offset in bytes for the start
* of the extent from the beginning of the disk */
__u64 fe_length; /* length in bytes for this extent */
- __u64 fe_reserved64[2];
+ __u64 fe_phys_length; /* physical length in bytes for this extent,
+ * undefined if DATA_COMPRESSED not set */
+ __u64 fe_reserved64;
__u32 fe_flags; /* FIEMAP_EXTENT_* flags for this extent */
__u32 fe_reserved[3];
};
struct fiemap {
- __u64 fm_start; /* logical offset (inclusive) at
+ __u64 fm_start; /* logical offset in bytes (inclusive) at
* which to start mapping (in) */
- __u64 fm_length; /* logical length of mapping which
+ __u64 fm_length; /* logical length in bytes of mapping which
* userspace wants (in) */
__u32 fm_flags; /* FIEMAP_FLAG_* flags for request (in/out) */
__u32 fm_mapped_extents;/* number of extents that were mapped (out) */
@@ -51,8 +53,10 @@ struct fiemap {
* Sets EXTENT_UNKNOWN. */
#define FIEMAP_EXTENT_ENCODED 0x00000008 /* Data can not be read
* while fs is unmounted */
+#define FIEMAP_EXTENT_DATA_COMPRESSED 0x00000040 /* Data is compressed by fs.
+ * Sets EXTENT_ENCODED. */
#define FIEMAP_EXTENT_DATA_ENCRYPTED 0x00000080 /* Data is encrypted by fs.
- * Sets EXTENT_NO_BYPASS. */
+ * Sets EXTENT_ENCODED. */
#define FIEMAP_EXTENT_NOT_ALIGNED 0x00000100 /* Extent offsets may not be
* block aligned. */
#define FIEMAP_EXTENT_DATA_INLINE 0x00000200 /* Data mixed with metadata.
@@ -64,5 +68,7 @@ struct fiemap {
#define FIEMAP_EXTENT_MERGED 0x00001000 /* File does not natively
* support extents. Result
* merged for efficiency. */
+#define FIEMAP_EXTENT_NET 0x80000000 /* Data stored remotely.
+ * Sets EXTENT_ENCODED. */
#endif /* _LINUX_FIEMAP_H */
diff --git a/misc/filefrag.c b/misc/filefrag.c
index 6289899..7096abb 100644
--- a/misc/filefrag.c
+++ b/misc/filefrag.c
@@ -158,12 +158,14 @@ static void print_extent_info(struct fiemap_extent *fm_extent, int cur_ex,
print_flag(&flags, FIEMAP_EXTENT_UNKNOWN, buf, "unknown,");
print_flag(&flags, FIEMAP_EXTENT_DELALLOC, buf, "delalloc,");
+ print_flag(&flags, FIEMAP_EXTENT_DATA_COMPRESSED, buf, "compressed,");
print_flag(&flags, FIEMAP_EXTENT_DATA_ENCRYPTED, buf, "encrypted,");
print_flag(&flags, FIEMAP_EXTENT_NOT_ALIGNED, buf, "not_aligned,");
print_flag(&flags, FIEMAP_EXTENT_DATA_INLINE, buf, "inline,");
print_flag(&flags, FIEMAP_EXTENT_DATA_TAIL, buf, "tail_packed,");
print_flag(&flags, FIEMAP_EXTENT_UNWRITTEN, buf, "unwritten,");
print_flag(&flags, FIEMAP_EXTENT_MERGED, buf, "merged,");
+ print_flag(&flags, FIEMAP_EXTENT_NET, buf, "net,");
print_flag(&flags, FIEMAP_EXTENT_LAST, buf, "last,");
/* Print unknown flags in hex format. Known flags are already printed
* above and will have their bit cleared from "flags". */
--
1.7.3.4
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