Hi, The patch looks OK despite the typos and lack of proper formatting on the commit message.
But honestly, I don't know if this patch is even mergeable considering you looked at the Linux kernel's source code for this. The patch was already trivial enough if you looked at the documentation and the FreeBSD driver (as I had done in the past but never got to fixing this considering I don't even know if unwritten extents can appear in the wild). I *cannot* stress this enough: Ext4Pkg is a clean room implementation of ext4 licensed under the BSD-2-Clause-Patent license (which is NOT compatible with GPLv2) and cannot have random Linux kernel bits, or any other incompatibly-licensed project's bits for that matter. Best regards, Pedro On Wed, Oct 27, 2021 at 2:37 PM qi zhou <atm...@outlook.com> wrote: > From: "Qi Zhou" <atm...@outlook.com> > Subject: [PATCH] unwritten extent suuport > > the real lenght of uninitialized/unwritten extent should be (ee_len - (1UL > << 15)), and > all related block should been read as zeros. see: > > https://github.com/torvalds/linux/blob/d25f27432f80a800a3592db128254c8140bd71bf/fs/ext4/ext4_extents.h#L156 > > Signed-off-by: Qi Zhou <atm...@outlook.com> > --- > Features/Ext4Pkg/Ext4Dxe/Ext4Disk.h | 5 +++++ > Features/Ext4Pkg/Ext4Dxe/Extents.c | 4 ++-- > Features/Ext4Pkg/Ext4Dxe/Inode.c | 5 +++++ > 3 files changed, 12 insertions(+), 2 deletions(-) > > diff --git a/Features/Ext4Pkg/Ext4Dxe/Ext4Disk.h > b/Features/Ext4Pkg/Ext4Dxe/Ext4Disk.h > index 070eb5a..7ca8eee 100644 > --- a/Features/Ext4Pkg/Ext4Dxe/Ext4Disk.h > +++ b/Features/Ext4Pkg/Ext4Dxe/Ext4Disk.h > @@ -402,6 +402,11 @@ typedef struct { > > #define EXT4_MIN_DIR_ENTRY_LEN 8 > > +#define EXTENT_INIT_MAX_LEN (1UL << 15) > + > +#define EXTENT_REAL_LEN(x) ((UINT16)(x <= EXTENT_INIT_MAX_LEN ? x : (x - > EXTENT_INIT_MAX_LEN))) > +#define EXTENT_IS_UNWRITTEN(x) (x > EXTENT_INIT_MAX_LEN) > + > // This on-disk structure is present at the bottom of the extent tree > typedef struct { > // First logical block > diff --git a/Features/Ext4Pkg/Ext4Dxe/Extents.c > b/Features/Ext4Pkg/Ext4Dxe/Extents.c > index 5fa2fe0..21af573 100644 > --- a/Features/Ext4Pkg/Ext4Dxe/Extents.c > +++ b/Features/Ext4Pkg/Ext4Dxe/Extents.c > @@ -332,7 +332,7 @@ Ext4GetExtent ( > return EFI_NO_MAPPING; > } > > - if (!(LogicalBlock >= Ext->ee_block && Ext->ee_block + Ext->ee_len > > LogicalBlock)) { > + if (!(LogicalBlock >= Ext->ee_block && Ext->ee_block + > EXTENT_REAL_LEN(Ext->ee_len) > LogicalBlock)) { > // This extent does not cover the block > if (Buffer != NULL) { > FreePool (Buffer); > @@ -413,7 +413,7 @@ Ext4ExtentsMapKeyCompare ( > Extent = UserStruct; > Block = (UINT32)(UINTN)StandaloneKey; > > - if (Block >= Extent->ee_block && Block < Extent->ee_block + > Extent->ee_len) { > + if (Block >= Extent->ee_block && Block < Extent->ee_block + > EXTENT_REAL_LEN(Extent->ee_len)) { > return 0; > } > > diff --git a/Features/Ext4Pkg/Ext4Dxe/Inode.c > b/Features/Ext4Pkg/Ext4Dxe/Inode.c > index 63cecec..d691ec7 100644 > --- a/Features/Ext4Pkg/Ext4Dxe/Inode.c > +++ b/Features/Ext4Pkg/Ext4Dxe/Inode.c > @@ -151,6 +151,11 @@ Ext4Read ( > // Potential improvement: In the future, we could get the hole's > tota > // size and memset all that > SetMem (Buffer, WasRead, 0); > + } else if(EXTENT_IS_UNWRITTEN(Extent.ee_len)) { > + HoleOff = CurrentSeek - (UINT64)Extent.ee_block * > Partition->BlockSize; > + HoleLen = EXTENT_REAL_LEN(Extent.ee_len) * Partition->BlockSize - > HoleOff; > + WasRead = HoleLen > RemainingRead ? RemainingRead : HoleLen; > + SetMem (Buffer, WasRead, 0); > } else { > ExtentStartBytes = MultU64x32 ( > LShiftU64 (Extent.ee_start_hi, 32) | > -- > 2.17.1 > > -- Pedro Falcato -=-=-=-=-=-=-=-=-=-=-=- Groups.io Links: You receive all messages sent to this group. View/Reply Online (#82753): https://edk2.groups.io/g/devel/message/82753 Mute This Topic: https://groups.io/mt/86629612/21656 Group Owner: devel+ow...@edk2.groups.io Unsubscribe: https://edk2.groups.io/g/devel/unsub [arch...@mail-archive.com] -=-=-=-=-=-=-=-=-=-=-=-
