tty: tty_driver: introduce TTY driver sub/types enums

Convert TTY_DRIVER_TYPE_*, and subtype macros to two enums:
tty_driver_type and tty_driver_subtype. This allows for easier
kernel-doc (later), g

tty: tty_driver: introduce TTY driver sub/types enums

Convert TTY_DRIVER_TYPE_*, and subtype macros to two enums:
tty_driver_type and tty_driver_subtype. This allows for easier
kernel-doc (later), grouping of these nicely, and proper checking.

The tty_driver's ::type and ::subtype now use these enums instead of
bare "short".

Signed-off-by: Jiri Slaby (SUSE) <[email protected]>
Link: https://lore.kernel.org/r/[email protected]
Signed-off-by: Greg Kroah-Hartman <[email protected]>

show more ...

tty: tty_driver: document both {,__}tty_alloc_driver() properly

__tty_alloc_driver()'s kernel-doc needed some care: describe the return
value using the standard "Returns:", and use the new enum tty_

tty: tty_driver: document both {,__}tty_alloc_driver() properly

__tty_alloc_driver()'s kernel-doc needed some care: describe the return
value using the standard "Returns:", and use the new enum tty_driver_flag
for @flags.

Then, the tty_alloc_driver() macro was undocumented, but referenced many
times in the docs. Copy the docs from the above (except the @owner
parameter, obviously).

Signed-off-by: Jiri Slaby (SUSE) <[email protected]>
Link: https://lore.kernel.org/r/[email protected]
Signed-off-by: Greg Kroah-Hartman <[email protected]>

show more ...

tty: tty_driver: convert "TTY Driver Flags" to an enum

Convert TTY_DRIVER_* macros (flags) to an enum. This allows for easier
kernel-doc (the comment needed fine tuning), grouping of these nicely,
a

tty: tty_driver: convert "TTY Driver Flags" to an enum

Convert TTY_DRIVER_* macros (flags) to an enum. This allows for easier
kernel-doc (the comment needed fine tuning), grouping of these nicely,
and proper checking.

Given these are flags, define them using modern BIT() instead of hex
constants.

It turns out (thanks, kernel-doc checker) that internal
TTY_DRIVER_INSTALLED was undocumented. Fix that too.

Signed-off-by: Jiri Slaby (SUSE) <[email protected]>
Link: https://lore.kernel.org/r/[email protected]
Signed-off-by: Greg Kroah-Hartman <[email protected]>

show more ...

tty: tty_driver: move TTY macros to the top

So that they can be referenced in structs once converted to enums (in
the next patches).

Signed-off-by: Jiri Slaby (SUSE) <[email protected]>
Link: ht

tty: tty_driver: move TTY macros to the top

So that they can be referenced in structs once converted to enums (in
the next patches).

Signed-off-by: Jiri Slaby (SUSE) <[email protected]>
Link: https://lore.kernel.org/r/[email protected]
Signed-off-by: Greg Kroah-Hartman <[email protected]>

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Documentation: move dev-tools debugging files to process/debugging/

Move gdb and kgdb debugging documentation to the dedicated
debugging directory (Documentation/process/debugging/).
Adjust the inde

Documentation: move dev-tools debugging files to process/debugging/

Move gdb and kgdb debugging documentation to the dedicated
debugging directory (Documentation/process/debugging/).
Adjust the index.rst files to follow the file movement.
Adjust files that refer to these moved files to follow the file movement.
Update location of kgdb.rst in MAINTAINERS file.
Add a link from dev-tools/index to process/debugging/index.

Note: translations are not updated.

Signed-off-by: Randy Dunlap <[email protected]>
Cc: Sebastian Fricke <[email protected]>
Cc: Jonathan Corbet <[email protected]>
Cc: [email protected]
Cc: Jason Wessel <[email protected]>
Cc: Daniel Thompson <[email protected]>
Cc: Douglas Anderson <[email protected]>
Cc: [email protected]
Cc: [email protected]
Cc: Doug Anderson <[email protected]>
Cc: Alex Shi <[email protected]>
Cc: Hu Haowen <[email protected]>
Cc: Andrew Morton <[email protected]>
Cc: Greg Kroah-Hartman <[email protected]>
Cc: [email protected]
Acked-by: Greg Kroah-Hartman <[email protected]>
Acked-by: Daniel Thompson <[email protected]>
Reviewed-by: Douglas Anderson <[email protected]>
Signed-off-by: Jonathan Corbet <[email protected]>
Link: https://lore.kernel.org/r/[email protected]

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tty: add the option to have a tty reject a new ldisc

... and use it to limit the virtual terminals to just N_TTY. They are
kind of special, and in particular, the "con_write()" routine violates
the

tty: add the option to have a tty reject a new ldisc

... and use it to limit the virtual terminals to just N_TTY. They are
kind of special, and in particular, the "con_write()" routine violates
the "writes cannot sleep" rule that some ldiscs rely on.

This avoids the

BUG: sleeping function called from invalid context at kernel/printk/printk.c:2659

when N_GSM has been attached to a virtual console, and gsmld_write()
calls con_write() while holding a spinlock, and con_write() then tries
to get the console lock.

Tested-by: Tetsuo Handa <[email protected]>
Cc: Jiri Slaby <[email protected]>
Cc: Andrew Morton <[email protected]>
Cc: Daniel Starke <[email protected]>
Reported-by: syzbot <[email protected]>
Closes: https://syzkaller.appspot.com/bug?extid=dbac96d8e73b61aa559c
Signed-off-by: Linus Torvalds <[email protected]>
Link: https://lore.kernel.org/r/[email protected]
Signed-off-by: Greg Kroah-Hartman <[email protected]>

show more ...

tty: make tty_operations::send_xchar accept u8 char

tty_operations::send_xchar is one of the last users of 'char' type for
characters in the tty layer. Convert it to u8 now.

Signed-off-by: "Jiri Sl

tty: make tty_operations::send_xchar accept u8 char

tty_operations::send_xchar is one of the last users of 'char' type for
characters in the tty layer. Convert it to u8 now.

Signed-off-by: "Jiri Slaby (SUSE)" <[email protected]>
Cc: Karsten Keil <[email protected]>
Cc: Ulf Hansson <[email protected]>
Cc: Marcel Holtmann <[email protected]>
Cc: Johan Hedberg <[email protected]>
Cc: Luiz Augusto von Dentz <[email protected]>
Cc: [email protected]
Cc: [email protected]
Cc: [email protected]
Reviewed-by: Geert Uytterhoeven <[email protected]>
Link: https://lore.kernel.org/r/[email protected]
Signed-off-by: Greg Kroah-Hartman <[email protected]>

show more ...

tty: fix tty_operations types in documentation

Commits 95713967ba52 ("tty: make tty_operations::write()'s count
size_t") and dcaafbe6ee3b ("tty: propagate u8 data to
tty_operations::put_char()") cha

tty: fix tty_operations types in documentation

Commits 95713967ba52 ("tty: make tty_operations::write()'s count
size_t") and dcaafbe6ee3b ("tty: propagate u8 data to
tty_operations::put_char()") changed types of characters to u8, but
omitted to fix the documentation.

Fix the latter now.

Signed-off-by: Jiri Slaby (SUSE) <[email protected]>
Link: https://lore.kernel.org/r/[email protected]
Signed-off-by: Greg Kroah-Hartman <[email protected]>

show more ...

tty: make tty_operations::write()'s count size_t

Unify with the rest of the code. Use size_t for counts and ssize_t for
retval.

Signed-off-by: "Jiri Slaby (SUSE)" <[email protected]>
Link: https

tty: make tty_operations::write()'s count size_t

Unify with the rest of the code. Use size_t for counts and ssize_t for
retval.

Signed-off-by: "Jiri Slaby (SUSE)" <[email protected]>
Link: https://lore.kernel.org/r/[email protected]
Signed-off-by: Greg Kroah-Hartman <[email protected]>

show more ...

tty: propagate u8 data to tty_operations::put_char()

Data are now typed as u8. Propagate this change to
tty_operations::put_char().

Signed-off-by: "Jiri Slaby (SUSE)" <[email protected]>
Cc: Gee

tty: propagate u8 data to tty_operations::put_char()

Data are now typed as u8. Propagate this change to
tty_operations::put_char().

Signed-off-by: "Jiri Slaby (SUSE)" <[email protected]>
Cc: Geert Uytterhoeven <[email protected]>
Cc: Heiko Carstens <[email protected]>
Cc: Vasily Gorbik <[email protected]>
Cc: Alexander Gordeev <[email protected]>
Cc: Christian Borntraeger <[email protected]>
Cc: Sven Schnelle <[email protected]>
Cc: Karsten Keil <[email protected]>
Cc: Greg Kroah-Hartman <[email protected]>
Cc: Jiri Slaby <[email protected]>
Cc: Shawn Guo <[email protected]>
Cc: Sascha Hauer <[email protected]>
Cc: Pengutronix Kernel Team <[email protected]>
Cc: Fabio Estevam <[email protected]>
Cc: NXP Linux Team <[email protected]>
Cc: Mathias Nyman <[email protected]>
Link: https://lore.kernel.org/r/[email protected]
Signed-off-by: Greg Kroah-Hartman <[email protected]>

show more ...

tty: propagate u8 data to tty_operations::write()

Data are now typed as u8. Propagate this change to
tty_operations::write().

Signed-off-by: "Jiri Slaby (SUSE)" <[email protected]>
Cc: Richard H

tty: propagate u8 data to tty_operations::write()

Data are now typed as u8. Propagate this change to
tty_operations::write().

Signed-off-by: "Jiri Slaby (SUSE)" <[email protected]>
Cc: Richard Henderson <[email protected]>
Cc: Ivan Kokshaysky <[email protected]>
Cc: Matt Turner <[email protected]>
Cc: Geert Uytterhoeven <[email protected]>
Cc: Richard Weinberger <[email protected]>
Cc: Anton Ivanov <[email protected]>
Cc: Johannes Berg <[email protected]>
Cc: Chris Zankel <[email protected]>
Cc: Max Filippov <[email protected]>
Cc: Arnd Bergmann <[email protected]>
Cc: Vaibhav Gupta <[email protected]>
Cc: Jens Taprogge <[email protected]>
Cc: Karsten Keil <[email protected]>
Cc: Scott Branden <[email protected]>
Cc: Ulf Hansson <[email protected]>
Cc: "David S. Miller" <[email protected]>
Cc: Eric Dumazet <[email protected]>
Cc: Jakub Kicinski <[email protected]>
Cc: Paolo Abeni <[email protected]>
Cc: Heiko Carstens <[email protected]>
Cc: Vasily Gorbik <[email protected]>
Cc: Alexander Gordeev <[email protected]>
Cc: Christian Borntraeger <[email protected]>
Cc: Sven Schnelle <[email protected]>
Cc: David Lin <[email protected]>
Cc: Johan Hovold <[email protected]>
Cc: Alex Elder <[email protected]>
Cc: Laurentiu Tudor <[email protected]>
Cc: Jiri Kosina <[email protected]>
Cc: David Sterba <[email protected]>
Cc: Shawn Guo <[email protected]>
Cc: Sascha Hauer <[email protected]>
Cc: Pengutronix Kernel Team <[email protected]>
Cc: Fabio Estevam <[email protected]>
Cc: NXP Linux Team <[email protected]>
Cc: Arnaud Pouliquen <[email protected]>
Cc: Oliver Neukum <[email protected]>
Cc: Mathias Nyman <[email protected]>
Cc: Marcel Holtmann <[email protected]>
Cc: Johan Hedberg <[email protected]>
Cc: Luiz Augusto von Dentz <[email protected]>
Link: https://lore.kernel.org/r/[email protected]
Signed-off-by: Greg Kroah-Hartman <[email protected]>

show more ...

tty: remove TTY_DRIVER_MAGIC

According to Greg, in the context of magic numbers as defined in
magic-number.rst, "the tty layer should not need this and I'll gladly
take patches"

Acked-by: Jiri Slab

tty: remove TTY_DRIVER_MAGIC

According to Greg, in the context of magic numbers as defined in
magic-number.rst, "the tty layer should not need this and I'll gladly
take patches"

Acked-by: Jiri Slaby <[email protected]>
Signed-off-by: Ahelenia Ziemiańska <[email protected]>
Ref: https://lore.kernel.org/linux-doc/[email protected]/
Link: https://lore.kernel.org/r/723478a270a3858f27843cbec621df4d5d44efcc.1663288066.git.nabijaczleweli@nabijaczleweli.xyz
Signed-off-by: Greg Kroah-Hartman <[email protected]>

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termios: get rid of non-UAPI asm/termios.h

All non-UAPI asm/termios.h consist of include of UAPI counterpart
and, possibly, include of linux/uaccess.h

The latter can't be simply removed, even tho

termios: get rid of non-UAPI asm/termios.h

All non-UAPI asm/termios.h consist of include of UAPI counterpart
and, possibly, include of linux/uaccess.h

The latter can't be simply removed, even though nothing in
linux/termios.h doesn't depend upon it anymore - there are several
places that rely upon that indirect chain of includes to pull
linux/uaccess.h. So the include needs to be lifted out of there -
we lift into tty_driver.h, serdev.h and places that pull asm/termios.h,
but none of
* linux/uaccess.h (obvious)
* net/sock.h (pulls uaccess.h)
* linux/{tty,tty_driver,serdev}.h (tty.h pulls tty_driver.h)

That leaves us just with the include of UAPI asm/termios.h, which is
what <asm/termios.h> will resolve to if we simply remove non-UAPI header.

Signed-off-by: Al Viro <[email protected]>
Link: https://lore.kernel.org/r/YxDnKvYCHn/ogBUv@ZenIV
Signed-off-by: Greg Kroah-Hartman <[email protected]>

show more ...

tty: Make ->set_termios() old ktermios const

There should be no reason to adjust old ktermios which is going to get
discarded anyway.

Reviewed-by: Andy Shevchenko <[email protected]>
Signed

tty: Make ->set_termios() old ktermios const

There should be no reason to adjust old ktermios which is going to get
discarded anyway.

Reviewed-by: Andy Shevchenko <[email protected]>
Signed-off-by: Ilpo Järvinen <[email protected]>
Link: https://lore.kernel.org/r/[email protected]
Signed-off-by: Greg Kroah-Hartman <[email protected]>

show more ...

tty: reformat TTY_DRIVER_ flags into kernel-doc

We want to reference TTY_DRIVER_* flags in Documentation/ later in this
series. But the current documentation in the TTY_DRIVER_*'s header does
not al

tty: reformat TTY_DRIVER_ flags into kernel-doc

We want to reference TTY_DRIVER_* flags in Documentation/ later in this
series. But the current documentation in the TTY_DRIVER_*'s header does
not allow that. Reformat it to kernel-doc using "DOC" directive and
line-feeds, so that we can include it as it is.

Signed-off-by: Jiri Slaby <[email protected]>
Link: https://lore.kernel.org/r/[email protected]
Signed-off-by: Greg Kroah-Hartman <[email protected]>

show more ...

tty: combine tty_operations triple docs into kernel-doc

In Documentation/driver-api/serial/tty.rst, there are triplicated texts
about some struct tty_operations' hooks. Combine them into existing
ke

tty: combine tty_operations triple docs into kernel-doc

In Documentation/driver-api/serial/tty.rst, there are triplicated texts
about some struct tty_operations' hooks. Combine them into existing
kernel-doc comments of struct tty_operations and drop them from the
Documentation/.

Signed-off-by: Jiri Slaby <[email protected]>
Link: https://lore.kernel.org/r/[email protected]
Signed-off-by: Greg Kroah-Hartman <[email protected]>

show more ...

tty: add kernel-doc for tty_operations

tty_operations structure was already documented in a standalone comment
in the header beginning.

Move it right before the structure and reformat it so it comp

tty: add kernel-doc for tty_operations

tty_operations structure was already documented in a standalone comment
in the header beginning.

Move it right before the structure and reformat it so it complies to
kernel-doc. That way, we can include it in Documentation/ later in this
series.

Note that we named proc_show's parameters, so that we can reference
them in the text.

Signed-off-by: Jiri Slaby <[email protected]>
Link: https://lore.kernel.org/r/[email protected]
Signed-off-by: Greg Kroah-Hartman <[email protected]>

show more ...

tty: add kernel-doc for tty_driver

tty_driver used to have only short comments along its members. Convert
them into proper kernel-doc comments in front of the structure. And add
some more explanatio

tty: add kernel-doc for tty_driver

tty_driver used to have only short comments along its members. Convert
them into proper kernel-doc comments in front of the structure. And add
some more explanation to them where needed.

The whole structure handling is documented at the end too.

Signed-off-by: Jiri Slaby <[email protected]>
Link: https://lore.kernel.org/r/[email protected]
Signed-off-by: Greg Kroah-Hartman <[email protected]>

show more ...

tty: Fix extra "not" in TTY_DRIVER_REAL_RAW description

TTY_DRIVER_REAL_RAW flag (which is always set for e.g. serial ports)
documentation says that driver must always set special character
handling

tty: Fix extra "not" in TTY_DRIVER_REAL_RAW description

TTY_DRIVER_REAL_RAW flag (which is always set for e.g. serial ports)
documentation says that driver must always set special character
handling flags in certain conditions.

However, as the following sentence makes clear, what is actually
intended is the opposite.

Fix that by removing the unintended double negation.

Acked-by: Johan Hovold <[email protected]>
Signed-off-by: Anssi Hannula <[email protected]>
Link: https://lore.kernel.org/r/[email protected]
Signed-off-by: Greg Kroah-Hartman <[email protected]>

show more ...

tty: remove extern from functions in tty headers

After the recent headers cleanup, some function declarations still have
extern before them. It is superfluous (for function declarations), so
remove

tty: remove extern from functions in tty headers

After the recent headers cleanup, some function declarations still have
extern before them. It is superfluous (for function declarations), so
remove extern from those which still have it.

This unifies them with the rest of the files.

Signed-off-by: Jiri Slaby <[email protected]>
Link: https://lore.kernel.org/r/[email protected]
Signed-off-by: Greg Kroah-Hartman <[email protected]>

show more ...

tty: drop put_tty_driver

put_tty_driver() is an alias for tty_driver_kref_put(). There is no need
for two exported identical functions, therefore switch all users of
old put_tty_driver() to new tty_

tty: drop put_tty_driver

put_tty_driver() is an alias for tty_driver_kref_put(). There is no need
for two exported identical functions, therefore switch all users of
old put_tty_driver() to new tty_driver_kref_put() and remove the former
for good.

Cc: Richard Henderson <[email protected]>
Cc: Ivan Kokshaysky <[email protected]>
Cc: Matt Turner <[email protected]>
Cc: Geert Uytterhoeven <[email protected]>
Cc: Jeff Dike <[email protected]>
Cc: Richard Weinberger <[email protected]>
Cc: Anton Ivanov <[email protected]>
Cc: Chris Zankel <[email protected]>
Cc: Max Filippov <[email protected]>
Cc: Arnd Bergmann <[email protected]>
Cc: Greg Kroah-Hartman <[email protected]>
Cc: Samuel Iglesias Gonsalvez <[email protected]>
Cc: Jens Taprogge <[email protected]>
Cc: Karsten Keil <[email protected]>
Cc: Scott Branden <[email protected]>
Cc: Ulf Hansson <[email protected]>
Cc: "David S. Miller" <[email protected]>
Cc: Jakub Kicinski <[email protected]>
Cc: Heiko Carstens <[email protected]>
Cc: Vasily Gorbik <[email protected]>
Cc: Christian Borntraeger <[email protected]>
Cc: David Lin <[email protected]>
Cc: Johan Hovold <[email protected]>
Cc: Alex Elder <[email protected]>
Cc: Jiri Slaby <[email protected]>
Cc: Laurentiu Tudor <[email protected]>
Cc: Jiri Kosina <[email protected]>
Cc: David Sterba <[email protected]>
Cc: Shawn Guo <[email protected]>
Cc: Sascha Hauer <[email protected]>
Cc: Pengutronix Kernel Team <[email protected]>
Cc: Fabio Estevam <[email protected]>
Cc: NXP Linux Team <[email protected]>
Cc: Oliver Neukum <[email protected]>
Cc: Felipe Balbi <[email protected]>
Cc: Mathias Nyman <[email protected]>
Cc: Marcel Holtmann <[email protected]>
Cc: Johan Hedberg <[email protected]>
Cc: Luiz Augusto von Dentz <[email protected]>
Acked-by: Alex Elder <[email protected]>
Acked-by: Christian Borntraeger <[email protected]>
Acked-by: Max Filippov <[email protected]>
Acked-by: David Sterba <[email protected]>
Acked-by: Samuel Iglesias Gonsálvez <[email protected]>
Signed-off-by: Jiri Slaby <[email protected]>
Link: https://lore.kernel.org/r/[email protected]
Signed-off-by: Greg Kroah-Hartman <[email protected]>

show more ...

tty: make tty_set_operations an inline

Since commit f34d7a5b7010 (tty: The big operations rework) in 2008,
tty_set_operations() is a simple one-line assignment. There is no reason
for this to be an

tty: make tty_set_operations an inline

Since commit f34d7a5b7010 (tty: The big operations rework) in 2008,
tty_set_operations() is a simple one-line assignment. There is no reason
for this to be an exported function, hence move it to a header and make
an inline from that.

Signed-off-by: Jiri Slaby <[email protected]>
Link: https://lore.kernel.org/r/[email protected]
Signed-off-by: Greg Kroah-Hartman <[email protected]>

show more ...

tty: drop alloc_tty_driver

Noone uses this deprecated function now. So we can remove it.

Signed-off-by: Jiri Slaby <[email protected]>
Link: https://lore.kernel.org/r/20210723074317.32690-6-jslaby@sus

tty: drop alloc_tty_driver

Noone uses this deprecated function now. So we can remove it.

Signed-off-by: Jiri Slaby <[email protected]>
Link: https://lore.kernel.org/r/[email protected]
Signed-off-by: Greg Kroah-Hartman <[email protected]>

show more ...

tty: include kref.h in tty_driver.h

We use kref in tty_driver.h, but do not include kref.h. It is currently
included by linux/cdev.h -> linux/kobject.h -> linux/kref.h chain, so
everything is in ord

tty: include kref.h in tty_driver.h

We use kref in tty_driver.h, but do not include kref.h. It is currently
included by linux/cdev.h -> linux/kobject.h -> linux/kref.h chain, so
everything is in order only implicitly. So make this dependency
explicit.

Signed-off-by: Jiri Slaby <[email protected]>
Link: https://lore.kernel.org/r/[email protected]
Signed-off-by: Greg Kroah-Hartman <[email protected]>

show more ...

tty: move tty_driver related prototypes to tty_driver.h

We already have tty_driver.h, so cleanup tty.h a bit by moving out
tty_driver-related function prototypes into tty_driver.h.

Note that tty.h

tty: move tty_driver related prototypes to tty_driver.h

We already have tty_driver.h, so cleanup tty.h a bit by moving out
tty_driver-related function prototypes into tty_driver.h.

Note that tty.h already includes tty_driver.h.

Signed-off-by: Jiri Slaby <[email protected]>
Link: https://lore.kernel.org/r/[email protected]
Signed-off-by: Greg Kroah-Hartman <[email protected]>

show more ...