I tried this patch, with nodelalloc, the kernel did not crash! Previous it crashes in a few minutes. but the test did not stop after fill the file by specified 2G size I noticed the write() to write to the last fallocate extent(up to 2G) returns junk value. The testcase I got from Shehjart (who originally reported the problem) is http://www.gelato.unsw.edu.au/~shehjart/writefallocate.c command I use to reproduce the problem is ./writefallocate --filesize 2147483648 --wrblksize 65536 --fallocate 1048576 --filename /mnt/ext4/a --nounlink ............. offset: 2147024896, written: 65536^M offset: 2147090432, written: 65536^M offset: 2147155968, written: 65536^M offset: 2147221504, written: 65536^M offset: 2147287040, written: 65536^M offset: 2147352576, written: 65536^M offset: 2147418112, written: 65535^M offset: 2147483647, written: 18446744073709551615^M fallocate offset: 2147483647^M offset: 2147483646, written: 18446744073709551615^M offset: 2147483645, written: 18446744073709551615^M offset: 2147483644, written: 18446744073709551615^M offset: 2147483643, written: 18446744073709551615^M offset: 2147483642, written: 18446744073709551615^M offset: 2147483641, written: 18446744073709551615^M offset: 2147483640, written: 18446744073709551615^M Appearently the test has fallocate/fill the 2G file, but since the last write() returns 18446744073709551615, the offset is decreased, cause the test continue with a break, and writes to wrong offset 在 2008-07-18五的 18:47 +0530，Aneesh Kumar K.V写道： > We need to recalucate the path information on extent insert > even if depth doesn't change. > > Signed-off-by: Aneesh Kumar K.V <aneesh.kumar@xxxxxxxxxxxxxxxxxx> > --- > fs/ext4/extents.c | 41 +++++++++++++++++++++++------------------ > 1 files changed, 23 insertions(+), 18 deletions(-) > > diff --git a/fs/ext4/extents.c b/fs/ext4/extents.c > index 7bdaeec..9c8541e 100644 > --- a/fs/ext4/extents.c > +++ b/fs/ext4/extents.c > @@ -2462,7 +2462,10 @@ static int ext4_ext_convert_to_initialized(handle_t *handle, > unsigned int newdepth; > /* If extent has less than EXT4_EXT_ZERO_LEN zerout directly */ > if (allocated <= EXT4_EXT_ZERO_LEN) { > - /* Mark first half uninitialized. > + /* > + * iblock == ee_block is handled by the zerouout > + * at the beginning. > + * Mark first half uninitialized. > * Mark second half initialized and zero out the > * initialized extent > */ > @@ -2485,7 +2488,7 @@ static int ext4_ext_convert_to_initialized(handle_t *handle, > ex->ee_len = orig_ex.ee_len; > ext4_ext_store_pblock(ex, ext_pblock(&orig_ex)); > ext4_ext_dirty(handle, inode, path + depth); > - /* zeroed the full extent */ > + /* blocks available from iblock */ > return allocated; > > } else if (err) > @@ -2513,6 +2516,7 @@ static int ext4_ext_convert_to_initialized(handle_t *handle, > err = PTR_ERR(path); > return err; > } > + /* get the second half extent details */ > ex = path[depth].p_ext; > err = ext4_ext_get_access(handle, inode, > path + depth); > @@ -2542,6 +2546,7 @@ static int ext4_ext_convert_to_initialized(handle_t *handle, > ext4_ext_store_pblock(ex, ext_pblock(&orig_ex)); > ext4_ext_dirty(handle, inode, path + depth); > /* zeroed the full extent */ > + /* blocks available from iblock */ > return allocated; > > } else if (err) > @@ -2557,23 +2562,22 @@ static int ext4_ext_convert_to_initialized(handle_t *handle, > */ > orig_ex.ee_len = cpu_to_le16(ee_len - > ext4_ext_get_actual_len(ex3)); > - if (newdepth != depth) { > - depth = newdepth; > - ext4_ext_drop_refs(path); > - path = ext4_ext_find_extent(inode, iblock, path); > - if (IS_ERR(path)) { > - err = PTR_ERR(path); > - goto out; > - } > - eh = path[depth].p_hdr; > - ex = path[depth].p_ext; > - if (ex2 != &newex) > - ex2 = ex; > - > - err = ext4_ext_get_access(handle, inode, path + depth); > - if (err) > - goto out; > + depth = newdepth; > + ext4_ext_drop_refs(path); > + path = ext4_ext_find_extent(inode, iblock, path); > + if (IS_ERR(path)) { > + err = PTR_ERR(path); > + goto out; > } > + eh = path[depth].p_hdr; > + ex = path[depth].p_ext; > + if (ex2 != &newex) > + ex2 = ex; > + > + err = ext4_ext_get_access(handle, inode, path + depth); > + if (err) > + goto out; > + > allocated = max_blocks; > > /* If extent has less than EXT4_EXT_ZERO_LEN and we are trying > @@ -2591,6 +2595,7 @@ static int ext4_ext_convert_to_initialized(handle_t *handle, > ext4_ext_store_pblock(ex, ext_pblock(&orig_ex)); > ext4_ext_dirty(handle, inode, path + depth); > /* zero out the first half */ > + /* blocks available from iblock */ > return allocated; > } > } -- To unsubscribe from this list: send the line "unsubscribe linux-ext4" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html
