This patch adds the ability for zfs to support file/dir name up to 1023
bytes. This number is chosen so we can support up to 255 4-byte
characters. This new feature is represented by the new feature flag
feature@longname.
A new dataset property "longname" is also introduced to toggle longname
support for each dataset individually. This property can be disabled,
even if it contains longname files. In such case, new file cannot be
created with longname but existing longname files can still be looked
up.
Note that, to my knowledge native Linux filesystems don't support name
longer than 255 bytes. So there might be programs not able to work with
longname.
Note that NFS server may needs to use exportfs_get_name to reconnect
dentries, and the buffer being passed is limit to NAME_MAX+1 (256). So
NFS may not work when longname is enabled.
Note, FreeBSD vfs layer imposes a limit of 255 name lengh, so even
though we add code to support it here, it won't actually work.
Reviewed-by: Tony Hutter <hutter2@llnl.gov>
Reviewed-by: Brian Behlendorf <behlendorf1@llnl.gov>
Reviewed-by: Alexander Motin <mav@FreeBSD.org>
Signed-off-by: Chunwei Chen <david.chen@nutanix.com>
Closes#15921
This patch is preparatory work for long name feature. It changes all
users of zap_attribute_t to allocate it from kmem instead of stack. It
also make zap_attribute_t and zap_name_t structure variable length.
Reviewed-by: Tony Hutter <hutter2@llnl.gov>
Reviewed-by: Brian Behlendorf <behlendorf1@llnl.gov>
Reviewed-by: Alexander Motin <mav@FreeBSD.org>
Signed-off-by: Chunwei Chen <david.chen@nutanix.com>
Closes#15921
The docs for drr_versioninfo have marked the top 32 bits as "reserved"
since its introduction (illumos/illumos-gate@9e69d7d). There's no
indication of why they're reserved, so it seems uncontroversial to make
a lot more flags available.
I'm keeping the top eight reserved, and explicitly calling them out as
such, so we can extend the header further in the future if we run out of
flags or want to do some kind of change that isn't about feature flags.
Sponsored-by: Klara, Inc.
Sponsored-by: Wasabi Technology, Inc.
Reviewed-by: Paul Dagnelie <pcd@delphix.com>
Reviewed-by: Alexander Motin <mav@FreeBSD.org>
Reviewed-by: Brian Behlendorf <behlendorf1@llnl.gov>
Signed-off-by: Rob Norris <rob.norris@klarasystems.com>
Closes#15454
ZIL log record structs (lr_XX_t) are frequently allocated with extra
space after the struct to carry variable-sized "payload" items.
Linux 6.10+ compiled with CONFIG_FORTIFY_SOURCE has been doing runtime
bounds checking on memcpy() calls. Because these types had no indicator
that they might use more space than their simple definition,
__fortify_memcpy_chk will frequently complain about overruns eg:
memcpy: detected field-spanning write (size 7) of single field
"lr + 1" at zfs_log.c:425 (size 0)
memcpy: detected field-spanning write (size 9) of single field
"(char *)(lr + 1)" at zfs_log.c:593 (size 0)
memcpy: detected field-spanning write (size 4) of single field
"(char *)(lr + 1) + snamesize" at zfs_log.c:594 (size 0)
memcpy: detected field-spanning write (size 7) of single field
"lr + 1" at zfs_log.c:425 (size 0)
memcpy: detected field-spanning write (size 9) of single field
"(char *)(lr + 1)" at zfs_log.c:593 (size 0)
memcpy: detected field-spanning write (size 4) of single field
"(char *)(lr + 1) + snamesize" at zfs_log.c:594 (size 0)
memcpy: detected field-spanning write (size 7) of single field
"lr + 1" at zfs_log.c:425 (size 0)
memcpy: detected field-spanning write (size 9) of single field
"(char *)(lr + 1)" at zfs_log.c:593 (size 0)
memcpy: detected field-spanning write (size 4) of single field
"(char *)(lr + 1) + snamesize" at zfs_log.c:594 (size 0)
To fix this, this commit adds flex array fields to all lr_XX_t structs
that require them, and then uses those fields to access that
end-of-struct area rather than more complicated casts and pointer
addition.
Sponsored-by: https://despairlabs.com/sponsor/
Reviewed-by: Alexander Motin <mav@FreeBSD.org>
Reviewed-by: Brian Behlendorf <behlendorf1@llnl.gov>
Signed-off-by: Rob Norris <robn@despairlabs.com>
Closes#16501Closes#16539
Too many times, people's performance problems have amounted to
"somehow your SIMD support isn't working", and determining that
at runtime is difficult to describe to people.
This adds a /proc/spl/kstat/zfs/simd node, which exposes
metadata about which instructions ZFS thinks it can use,
on AArch64 and x86_64 Linux, to make investigating things
like this much easier.
Reviewed-by: Brian Behlendorf <behlendorf1@llnl.gov>
Signed-off-by: Rich Ercolani <rincebrain@gmail.com>
Closes#16530
ZLE compressor needs additional bytes to process
d_len argument efficiently.
Don't use BPE_PAYLOAD_SIZE as d_len with it
before we rework zle compressor somehow.
Reviewed-by: Brian Behlendorf <behlendorf1@llnl.gov>
Reviewed-by: Tony Hutter <hutter2@llnl.gov>
Reviewed-by: Alexander Motin <mav@FreeBSD.org>
Signed-off-by: George Melikov <mail@gmelikov.ru>
Closes#9416
Now default compression is lz4, which can stop
compression process by itself on incompressible data.
If there are additional size checks -
we will only make our compressratio worse.
New usable compression thresholds are:
- less than BPE_PAYLOAD_SIZE (embedded_data feature);
- at least one saved sector.
Old 12.5% threshold is left to minimize affect
on existing user expectations of CPU utilization.
If data wasn't compressed - it will be saved as
ZIO_COMPRESS_OFF, so if we really need to recompress
data without ashift info and check anything -
we can just compress it with zero threshold.
So, we don't need a new feature flag here!
Reviewed-by: Brian Behlendorf <behlendorf1@llnl.gov>
Reviewed-by: Tony Hutter <hutter2@llnl.gov>
Reviewed-by: Alexander Motin <mav@FreeBSD.org>
Signed-off-by: George Melikov <mail@gmelikov.ru>
Closes#9416
For now, userspace has no znode implementation. Some of the property and
path handling code is used there though and is the same on all
platforms, so we only need a single copy of it.
Reviewed by: Brian Behlendorf <behlendorf1@llnl.gov>
Reviewed-by: Alexander Motin <mav@FreeBSD.org>
Signed-off-by: Rob Norris <robn@despairlabs.com>
Sponsored-by: https://despairlabs.com/sponsor/Closes#16492
Following 2b069768a (#16479), anything gated on a kernel version before
4.18 can be always included/excluded.
Sponsored-by: https://despairlabs.com/sponsor/
Reviewed by: Brian Behlendorf <behlendorf1@llnl.gov>
Reviewed-by: Alexander Motin <mav@FreeBSD.org>
Reviewed-by: Tino Reichardt <milky-zfs@mcmilk.de>
Signed-off-by: Rob Norris <robn@despairlabs.com>
Closes#16545
Specializing cityhash4 on 32-bit architectures can reduce the size
of stack frames as well as instruction count. This is a tiny but
useful optimization, since some callers invoke it frequently.
When specializing into 1/2/3/4-arg versions, the stack usage
(in bytes) on some 32-bit arches are listed as follows:
- x86: 32, 32, 32, 40
- arm-v7a: 20, 20, 28, 36
- riscv: 0, 0, 0, 16
- power: 16, 16, 16, 32
- mipsel: 8, 8, 8, 24
And each actual argument (even if passing 0) contributes evenly
to the number of multiplication instructions generated:
- x86: 9, 12, 15 ,18
- arm-v7a: 6, 8, 10, 12
- riscv / power: 12, 18, 20, 24
- mipsel: 9, 12, 15, 19
On 64-bit architectures, the tendencies are similar. But both stack
sizes and instruction counts are significantly smaller thus negligible.
Reviewed by: Brian Behlendorf <behlendorf1@llnl.gov>
Reviewed-by: Alexander Motin <mav@FreeBSD.org>
Reviewed-by: Tino Reichardt <milky-zfs@mcmilk.de>
Signed-off-by: Shengqi Chen <harry-chen@outlook.com>
Closes#16131Closes#16483
We only use it on a specific way: to punch a hole in (make sparse) a
region of a file, in order to implement TRIM-like behaviour.
So, call the op "deallocate", and move the Linux-style mode flags down
into the Linux implementation, since they're an implementation detail.
FreeBSD gets a no-op stub (for the moment).
Sponsored-by: https://despairlabs.com/sponsor/
Reviewed by: Brian Behlendorf <behlendorf1@llnl.gov>
Reviewed-by: Alexander Motin <mav@FreeBSD.org>
Reviewed-by: Tino Reichardt <milky-zfs@mcmilk.de>
Signed-off-by: Rob Norris <robn@despairlabs.com>
Closes#16496
get_user_pages_unlocked() had stabilised by 4.9.
Sponsored-by: https://despairlabs.com/sponsor/
Reviewed-by: Brian Behlendorf <behlendorf1@llnl.gov>
Reviewed-by: Tony Hutter <hutter2@llnl.gov>
Reviewed-by: Tino Reichardt <milky-zfs@mcmilk.de>
Signed-off-by: Rob Norris <robn@despairlabs.com>
Closes#16479