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author | Linus Torvalds <torvalds@linux-foundation.org> | 2021-07-06 00:08:24 +0300 |
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committer | Linus Torvalds <torvalds@linux-foundation.org> | 2021-07-06 00:08:24 +0300 |
commit | c932ed0adb09a7fa6d6649ee04dd78c83ab07ada (patch) | |
tree | 02b055bd7b350e7aca9104a9c69330896bb6382b /drivers/tty/tty_buffer.c | |
parent | a16d8644bad461bb073b92e812080ea6715ddf2b (diff) | |
parent | 15279ebe99d7c6142d9f1a6ae4ded66c0f168678 (diff) | |
download | linux-c932ed0adb09a7fa6d6649ee04dd78c83ab07ada.tar.xz |
Merge tag 'tty-5.14-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/tty
Pull tty / serial updates from Greg KH:
"Here is the big set of tty and serial driver patches for 5.14-rc1.
A bit more than normal, but nothing major, lots of cleanups.
Highlights are:
- lots of tty api cleanups and mxser driver cleanups from Jiri
- build warning fixes
- various serial driver updates
- coding style cleanups
- various tty driver minor fixes and updates
- removal of broken and disable r3964 line discipline (finally!)
All of these have been in linux-next for a while with no reported
issues"
* tag 'tty-5.14-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/tty: (227 commits)
serial: mvebu-uart: remove unused member nb from struct mvebu_uart
arm64: dts: marvell: armada-37xx: Fix reg for standard variant of UART
dt-bindings: mvebu-uart: fix documentation
serial: mvebu-uart: correctly calculate minimal possible baudrate
serial: mvebu-uart: do not allow changing baudrate when uartclk is not available
serial: mvebu-uart: fix calculation of clock divisor
tty: make linux/tty_flip.h self-contained
serial: Prefer unsigned int to bare use of unsigned
serial: 8250: 8250_omap: Fix possible interrupt storm on K3 SoCs
serial: qcom_geni_serial: use DT aliases according to DT bindings
Revert "tty: serial: Add UART driver for Cortina-Access platform"
tty: serial: Add UART driver for Cortina-Access platform
MAINTAINERS: add me back as mxser maintainer
mxser: Documentation, fix typos
mxser: Documentation, make the docs up-to-date
mxser: Documentation, remove traces of callout device
mxser: introduce mxser_16550A_or_MUST helper
mxser: rename flags to old_speed in mxser_set_serial_info
mxser: use port variable in mxser_set_serial_info
mxser: access info->MCR under info->slock
...
Diffstat (limited to 'drivers/tty/tty_buffer.c')
-rw-r--r-- | drivers/tty/tty_buffer.c | 28 |
1 files changed, 19 insertions, 9 deletions
diff --git a/drivers/tty/tty_buffer.c b/drivers/tty/tty_buffer.c index 9733469a14b2..635d0af229b7 100644 --- a/drivers/tty/tty_buffer.c +++ b/drivers/tty/tty_buffer.c @@ -32,8 +32,8 @@ * We default to dicing tty buffer allocations to this many characters * in order to avoid multiple page allocations. We know the size of * tty_buffer itself but it must also be taken into account that the - * the buffer is 256 byte aligned. See tty_buffer_find for the allocation - * logic this must match + * buffer is 256 byte aligned. See tty_buffer_find for the allocation + * logic this must match. */ #define TTY_BUFFER_PAGE (((PAGE_SIZE - sizeof(struct tty_buffer)) / 2) & ~0xFF) @@ -88,9 +88,10 @@ EXPORT_SYMBOL_GPL(tty_buffer_unlock_exclusive); * pre-allocate if memory guarantee is required). */ -int tty_buffer_space_avail(struct tty_port *port) +unsigned int tty_buffer_space_avail(struct tty_port *port) { int space = port->buf.mem_limit - atomic_read(&port->buf.mem_used); + return max(space, 0); } EXPORT_SYMBOL_GPL(tty_buffer_space_avail); @@ -169,7 +170,8 @@ static struct tty_buffer *tty_buffer_alloc(struct tty_port *port, size_t size) } /* Should possibly check if this fails for the largest buffer we - have queued and recycle that ? */ + * have queued and recycle that ? + */ if (atomic_read(&port->buf.mem_used) > port->buf.mem_limit) return NULL; p = kmalloc(sizeof(struct tty_buffer) + 2 * size, GFP_ATOMIC); @@ -242,7 +244,7 @@ void tty_buffer_flush(struct tty_struct *tty, struct tty_ldisc *ld) } /** - * tty_buffer_request_room - grow tty buffer if needed + * __tty_buffer_request_room - grow tty buffer if needed * @port: tty port * @size: size desired * @flags: buffer flags if new buffer allocated (default = 0) @@ -312,11 +314,13 @@ int tty_insert_flip_string_fixed_flag(struct tty_port *port, const unsigned char *chars, char flag, size_t size) { int copied = 0; + do { int goal = min_t(size_t, size - copied, TTY_BUFFER_PAGE); int flags = (flag == TTY_NORMAL) ? TTYB_NORMAL : 0; int space = __tty_buffer_request_room(port, goal, flags); struct tty_buffer *tb = port->buf.tail; + if (unlikely(space == 0)) break; memcpy(char_buf_ptr(tb, tb->used), chars, space); @@ -326,7 +330,8 @@ int tty_insert_flip_string_fixed_flag(struct tty_port *port, copied += space; chars += space; /* There is a small chance that we need to split the data over - several buffers. If this is the case we must loop */ + * several buffers. If this is the case we must loop. + */ } while (unlikely(size > copied)); return copied; } @@ -348,10 +353,12 @@ int tty_insert_flip_string_flags(struct tty_port *port, const unsigned char *chars, const char *flags, size_t size) { int copied = 0; + do { int goal = min_t(size_t, size - copied, TTY_BUFFER_PAGE); int space = tty_buffer_request_room(port, goal); struct tty_buffer *tb = port->buf.tail; + if (unlikely(space == 0)) break; memcpy(char_buf_ptr(tb, tb->used), chars, space); @@ -361,7 +368,8 @@ int tty_insert_flip_string_flags(struct tty_port *port, chars += space; flags += space; /* There is a small chance that we need to split the data over - several buffers. If this is the case we must loop */ + * several buffers. If this is the case we must loop. + */ } while (unlikely(size > copied)); return copied; } @@ -431,8 +439,10 @@ int tty_prepare_flip_string(struct tty_port *port, unsigned char **chars, size_t size) { int space = __tty_buffer_request_room(port, size, TTYB_NORMAL); + if (likely(space)) { struct tty_buffer *tb = port->buf.tail; + *chars = char_buf_ptr(tb, tb->used); if (~tb->flags & TTYB_NORMAL) memset(flag_buf_ptr(tb, tb->used), TTY_NORMAL, space); @@ -455,7 +465,7 @@ EXPORT_SYMBOL_GPL(tty_prepare_flip_string); * Returns the number of bytes processed */ int tty_ldisc_receive_buf(struct tty_ldisc *ld, const unsigned char *p, - char *f, int count) + const char *f, int count) { if (ld->ops->receive_buf2) count = ld->ops->receive_buf2(ld->tty, p, f, count); @@ -472,7 +482,7 @@ static int receive_buf(struct tty_port *port, struct tty_buffer *head, int count) { unsigned char *p = char_buf_ptr(head, head->read); - char *f = NULL; + const char *f = NULL; int n; if (~head->flags & TTYB_NORMAL) |