similar to: Are enormous extents harmful?

When using "-U" option with btrfs-corrupt-block, it will cause a segfault due to a missing break in getopt switch. Reported-by: Wang Shilong <wangsl.fnst@cn.fujitsu.com> Signed-off-by: Qu Wenruo <quwenruo@cn.fujitsu.com> --- btrfs-corrupt-block.c | 1 + 1 file changed, 1 insertion(+) diff --git a/btrfs-corrupt-block.c b/btrfs-corrupt-block.c index f0c14a9..a2828d4 100644

The current btrfs support did not handled multiple stripes stored in chunk items, hence skipping the physical addresses that were needed to do the mapping. Besides, the chunk tree may contain DEV_ITEM keys which store information on all of the underlying block devices, so we must skip them instead of finishing lookup. The bug was reproduced with btrfs-progs v4.2.2. Cc: Gene Cumm <gene.cumm

When offset + length == exts->end the code which is shortening the extents is subtracting 0 from length. And it is not optimized out. Signed-off-by: Martin Kletzander <mkletzan@redhat.com> --- server/extents.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) diff --git a/server/extents.c b/server/extents.c index d3d1a15ab97c..c422491601f0 100644 --- a/server/extents.c +++

On 3/26/19 4:17 PM, Richard W.M. Jones wrote: > This pair of calls allows plugins to describe which extents in the > virtual disk are allocated, holes or zeroes. > --- > +=head2 C<.extents> > + > + int extents (void *handle, uint32_t count, uint64_t offset, > + uint32_t flags, struct nbdkit_extents *extents); > + > +During the data serving phase, this

On Tue, Jul 07, 2020 at 05:22:46PM -0500, Eric Blake wrote: [...] > +/* Compute aligned extents on behalf of a filter. */ > +int > +nbdkit_extents_aligned (struct nbdkit_next_ops *next_ops, > + nbdkit_backend *nxdata, > + uint32_t count, uint64_t offset, > + uint32_t flags, uint32_t align, > +

A devious plugin can cause an 8-fold increase in the reply size in relation to the request size, by alternating status every byte of the request. In the worst case, this can cause the client to reject our response and kill the connection because the response is too large. What's more, it consumes a lot of memory to track that many extents. Let's put an upper bound on the maximum number of

On Tue, Mar 12, 2019 at 11:20:25AM +0000, Richard W.M. Jones wrote: >This pair of calls allows plugins to describe which extents in the >virtual disk are allocated, holes or zeroes. >--- > docs/nbdkit-filter.pod | 22 +++++++++++ > docs/nbdkit-plugin.pod | 86 +++++++++++++++++++++++++++++++++++++++++ > include/nbdkit-common.h | 14 ++++++- > include/nbdkit-filter.h | 12 +++++-

Thanks: Nir Soffer. Enhances: commit c12e3cb150259f0058727a50341a2d14bb0015a3 --- plugins/python/nbdkit-python-plugin.pod | 3 +- plugins/python/python.c | 39 +++++++++++++++---------- 2 files changed, 25 insertions(+), 17 deletions(-) diff --git a/plugins/python/nbdkit-python-plugin.pod b/plugins/python/nbdkit-python-plugin.pod index d7b6033f..ddae677e 100644 ---

On 3/20/19 5:11 PM, Richard W.M. Jones wrote: > This uses lseek SEEK_DATA/SEEK_HOLE to search for allocated data and > holes in the underlying file. > --- > plugins/file/file.c | 139 ++++++++++++++++++++++++++++++++++++++++---- > 1 file changed, 129 insertions(+), 10 deletions(-) > > -int file_debug_zero; /* to enable: -D file.zero=1 */ > +/* Any callbacks

On Tue, Mar 12, 2019 at 07:51:57AM -0500, Eric Blake wrote: > On 3/12/19 6:20 AM, Richard W.M. Jones wrote: > > This tentative commit implements extents/can_extents, roughly as > > discussed in the previous thread here: > > > > https://www.redhat.com/archives/libguestfs/2019-March/msg00017.html > > > > I can't say that I'm a big fan of having the

Hello, I''m currently trying to understand how compression in btrfs works. I could not find any detailed description about it. So here are my questions. 1. How is decided what to compress and what not? After a fast test with a 2g image file, I''ve looked into the extents of that file with find-new and it turned out that only some of the first extents were compressed. The file was

On 3/28/19 11:18 AM, Richard W.M. Jones wrote: > --- > filters/truncate/truncate.c | 55 +++++++++++++++++++++++++++++++++++++ > 1 file changed, 55 insertions(+) > > + > + /* If the entire request is beyond the end of the underlying plugin > + * then this is the easy case: return a hole. > + */ > + if (offset >= real_size_copy) > + return

On 3/28/19 11:18 AM, Richard W.M. Jones wrote: > This new pair of callbacks allows plugins to describe which extents in > the virtual disk are allocated, holes or zeroes. > --- > +++ b/server/extents.c > @@ -0,0 +1,210 @@ > +/* nbdkit > + * Copyright (C) 2019 Red Hat Inc. > + * All rights reserved. We started work on this phrase but it got waylaid by extents work; maybe

On 3/20/19 5:11 PM, Richard W.M. Jones wrote: > These plugins are both based on the same sparse array structure which > supports a simple implementation of extents. > --- > +int > +sparse_array_extents (struct sparse_array *sa, > + uint32_t count, uint64_t offset, > + struct nbdkit_extents *extents) > +{ > + uint32_t n, type;

On 3/28/19 11:18 AM, Richard W.M. Jones wrote: > These plugins are both based on the same sparse array structure which > supports a simple implementation of extents. > --- > common/sparse/sparse.h | 7 +- > common/sparse/sparse.c | 37 ++++++++++- > plugins/data/data.c | 16 ++++- > plugins/memory/memory.c | 16 ++++- > README |

When querying the extents of the underlying plugin, we should only translate the starting offset, and let the plugin report for at least as many bytes as our range permits. Otherwise, short-changing the range causes bad behavior such as returning 0 extents, or even failing the creation of an extents tracker: $ cat script case "$1" in get_size) echo 1m;; can_extents) ;;

The current btrfs support did not handled multiple stripes stored in chunk items, hence skipping the physical addresses that were needed to do the mapping. Besides, the chunk tree may contain DEV_ITEM keys which store information on all of the underlying block devices, so we must skip them instead of finishing lookup. The bug was reproduced with btrfs-progs v4.2.2. Cc: Gene Cumm <gene.cumm

On 4/23/19 4:49 PM, Richard W.M. Jones wrote: >> >> ...to here, after the final nbdkit_add_extent, so that we can return a >> larger extent than the client's request. I remember when I originally >> asked, you declined due to odd interactions with REQ_ONE semantics, but >> since then, we changed how add_extent() works. Does it work now to defer >> the

The current btrfs support did not handled multiple stripes stored in chunk items, hence skipping the physical addresses that were needed to do the mapping. Besides, the chunk tree may contain DEV_ITEM keys which store information on all of the underlying block devices, so we must skip them instead of finishing lookup. The bug was reproduced with btrfs-progs v4.2.2. Cc: Gene Cumm <gene.cumm

On 3/20/19 5:11 PM, Richard W.M. Jones wrote: > Allows you to safely use nbdkit-offset-filter on top of a plugin > supporting extents. > --- > filters/offset/offset.c | 35 +++++++++++++++++++++++++++++++++++ > 1 file changed, 35 insertions(+) If we don't change our minds on the interface in patch 1, then this looks correct. > +/* Extents. */ > +static int >