system/linux
system/linux
1
0
Fork 0
mirror of https://github.com/torvalds/linux synced 2024-09-19 18:46:35 +00:00
Code Issues Packages Projects Releases Wiki Activity

bpf,docs: Remove KF_KPTR_GET from documentation

Browse source 
A prior patch removed KF_KPTR_GET from the kernel. Now that it's no
longer accessible to kfunc authors, this patch removes it from the BPF
kfunc documentation.

Signed-off-by: David Vernet <void@manifault.com>
Link: https://lore.kernel.org/r/20230416084928.326135-4-void@manifault.com
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
This commit is contained in:
David Vernet 2023-04-16 03:49:28 -05:00 committed by Alexei Starovoitov
parent 7b4ddf3920
commit 530474e6d0
1 changed files with 6 additions and 15 deletions
Show stats Download patch file Download diff file Expand all files Collapse all files

21
Documentation/bpf/kfuncs.rst
View file

@ -184,16 +184,7 @@ in. All copies of the pointer being released are invalidated as a result of
invoking kfunc with this flag. KF_RELEASE kfuncs automatically receive the
protection afforded by the KF_TRUSTED_ARGS flag described below.
2.4.4 KF_KPTR_GET flag
----------------------
The KF_KPTR_GET flag is used to indicate that the kfunc takes the first argument
as a pointer to kptr, safely increments the refcount of the object it points to,
and returns a reference to the user. The rest of the arguments may be normal
arguments of a kfunc. The KF_KPTR_GET flag should be used in conjunction with
KF_ACQUIRE and KF_RET_NULL flags.
2.4.5 KF_TRUSTED_ARGS flag
2.4.4 KF_TRUSTED_ARGS flag
--------------------------
The KF_TRUSTED_ARGS flag is used for kfuncs taking pointer arguments. It
@ -205,7 +196,7 @@ exception described below).
There are two types of pointers to kernel objects which are considered "valid":
1. Pointers which are passed as tracepoint or struct_ops callback arguments.
2. Pointers which were returned from a KF_ACQUIRE or KF_KPTR_GET kfunc.
2. Pointers which were returned from a KF_ACQUIRE kfunc.
Pointers to non-BTF objects (e.g. scalar pointers) may also be passed to
KF_TRUSTED_ARGS kfuncs, and may have a non-zero offset.
@ -232,13 +223,13 @@ In other words, you must:
2. Specify the type and name of the trusted nested field. This field must match
the field in the original type definition exactly.
2.4.6 KF_SLEEPABLE flag
2.4.5 KF_SLEEPABLE flag
-----------------------
The KF_SLEEPABLE flag is used for kfuncs that may sleep. Such kfuncs can only
be called by sleepable BPF programs (BPF_F_SLEEPABLE).
2.4.7 KF_DESTRUCTIVE flag
2.4.6 KF_DESTRUCTIVE flag
--------------------------
The KF_DESTRUCTIVE flag is used to indicate functions calling which is
@ -247,7 +238,7 @@ rebooting or panicking. Due to this additional restrictions apply to these
calls. At the moment they only require CAP_SYS_BOOT capability, but more can be
added later.
2.4.8 KF_RCU flag
2.4.7 KF_RCU flag
-----------------
The KF_RCU flag is a weaker version of KF_TRUSTED_ARGS. The kfuncs marked with
@ -260,7 +251,7 @@ also be KF_RET_NULL.
.. _KF_deprecated_flag:
2.4.9 KF_DEPRECATED flag
2.4.8 KF_DEPRECATED flag
------------------------
The KF_DEPRECATED flag is used for kfuncs which are scheduled to be