netfs: zero the tail of a short DIO/unbuffered readgrafted

The buffered read collector zero-fills the tail of a short read that
stops below the inode's i_size (netfs_clear_unread()), so a read that
races an extending write still returns the expected number of bytes.
The non-buffered collector path does no such thing: it just records
how much was transferred.

Add the same zero-fill for the non-buffered case, gated on
NETFS_SREQ_CLEAR_TAIL: a subreq's source sets that flag when a short
result from it is known to be safe to treat as a hole, as opposed to
NETFS_SREQ_HIT_EOF, which means the read genuinely ran off the end of
the file and should be reported short as-is. Only CLEAR_TAIL should
zero-fill here; a real EOF must stay a real short read.

No source currently sets CLEAR_TAIL on an unbuffered/DIO subrequest,
so this is inert on its own -- a following change teaches cifs to set
it in the one case that needs it.

Fixes: e2d46f2ec332 ("netfs: Change the read result collector to only use one work item")
Reviewed-by: David Howells <dhowells@redhat.com>
Reviewed-by: Namjae Jeon <linkinjeon@kernel.org>
Signed-off-by: Paulo Alcantara <pc@manguebit.org>
Cc: Christian Brauner <brauner@kernel.org>
Cc: Matthew Wilcox <willy@infradead.org>
Cc: Ronnie Sahlberg <ronniesahlberg@gmail.com>
Cc: Shyam Prasad N <sprasad@microsoft.com>
Cc: Tom Talpey <tom@talpey.com>
Cc: Bharath SM <bharathsm@microsoft.com>
Cc: stable@vger.kernel.org

1 files changed, 199 insertions, 0 deletions

diff --git a/drivers/extcon/extcon-rt8973a.h b/drivers/extcon/extcon-rt8973a.h
new file mode 100644
index 000000000..0d0d69fca
--- /dev/null
+++ b/drivers/extcon/extcon-rt8973a.h
@@ -0,0 +1,199 @@
+/* SPDX-License-Identifier: GPL-2.0-or-later */
+/*
+ * rt8973a.h
+ *
+ * Copyright (c) 2014 Samsung Electronics Co., Ltd
+ */
+
+#ifndef __LINUX_EXTCON_RT8973A_H
+#define __LINUX_EXTCON_RT8973A_H
+
+enum rt8973a_types {
+	TYPE_RT8973A,
+};
+
+/* RT8973A registers */
+enum rt8973A_reg {
+	RT8973A_REG_DEVICE_ID = 0x1,
+	RT8973A_REG_CONTROL1,
+	RT8973A_REG_INT1,
+	RT8973A_REG_INT2,
+	RT8973A_REG_INTM1,
+	RT8973A_REG_INTM2,
+	RT8973A_REG_ADC,
+	RT8973A_REG_RSVD_1,
+	RT8973A_REG_RSVD_2,
+	RT8973A_REG_DEV1,
+	RT8973A_REG_DEV2,
+	RT8973A_REG_RSVD_3,
+	RT8973A_REG_RSVD_4,
+	RT8973A_REG_RSVD_5,
+	RT8973A_REG_RSVD_6,
+	RT8973A_REG_RSVD_7,
+	RT8973A_REG_RSVD_8,
+	RT8973A_REG_RSVD_9,
+	RT8973A_REG_MANUAL_SW1,
+	RT8973A_REG_MANUAL_SW2,
+	RT8973A_REG_RSVD_10,
+	RT8973A_REG_RSVD_11,
+	RT8973A_REG_RSVD_12,
+	RT8973A_REG_RSVD_13,
+	RT8973A_REG_RSVD_14,
+	RT8973A_REG_RSVD_15,
+	RT8973A_REG_RESET,
+
+	RT8973A_REG_END,
+};
+
+/* Define RT8973A MASK/SHIFT constant */
+#define RT8973A_REG_DEVICE_ID_VENDOR_SHIFT	0
+#define RT8973A_REG_DEVICE_ID_VERSION_SHIFT	3
+#define RT8973A_REG_DEVICE_ID_VENDOR_MASK	(0x7 << RT8973A_REG_DEVICE_ID_VENDOR_SHIFT)
+#define RT8973A_REG_DEVICE_ID_VERSION_MASK	(0x1f << RT8973A_REG_DEVICE_ID_VERSION_SHIFT)
+
+#define RT8973A_REG_CONTROL1_INTM_SHIFT	0
+#define RT8973A_REG_CONTROL1_AUTO_CONFIG_SHIFT	2
+#define RT8973A_REG_CONTROL1_I2C_RST_EN_SHIFT	3
+#define RT8973A_REG_CONTROL1_SWITCH_OPEN_SHIFT	4
+#define RT8973A_REG_CONTROL1_CHGTYP_SHIFT	5
+#define RT8973A_REG_CONTROL1_USB_CHD_EN_SHIFT	6
+#define RT8973A_REG_CONTROL1_ADC_EN_SHIFT	7
+#define RT8973A_REG_CONTROL1_INTM_MASK		(0x1 << RT8973A_REG_CONTROL1_INTM_SHIFT)
+#define RT8973A_REG_CONTROL1_AUTO_CONFIG_MASK	(0x1 << RT8973A_REG_CONTROL1_AUTO_CONFIG_SHIFT)
+#define RT8973A_REG_CONTROL1_I2C_RST_EN_MASK	(0x1 << RT8973A_REG_CONTROL1_I2C_RST_EN_SHIFT)
+#define RT8973A_REG_CONTROL1_SWITCH_OPEN_MASK	(0x1 << RT8973A_REG_CONTROL1_SWITCH_OPEN_SHIFT)
+#define RT8973A_REG_CONTROL1_CHGTYP_MASK	(0x1 << RT8973A_REG_CONTROL1_CHGTYP_SHIFT)
+#define RT8973A_REG_CONTROL1_USB_CHD_EN_MASK	(0x1 << RT8973A_REG_CONTROL1_USB_CHD_EN_SHIFT)
+#define RT8973A_REG_CONTROL1_ADC_EN_MASK	(0x1 << RT8973A_REG_CONTROL1_ADC_EN_SHIFT)
+
+#define RT9873A_REG_INTM1_ATTACH_SHIFT		0
+#define RT9873A_REG_INTM1_DETACH_SHIFT		1
+#define RT9873A_REG_INTM1_CHGDET_SHIFT		2
+#define RT9873A_REG_INTM1_DCD_T_SHIFT		3
+#define RT9873A_REG_INTM1_OVP_SHIFT		4
+#define RT9873A_REG_INTM1_CONNECT_SHIFT		5
+#define RT9873A_REG_INTM1_ADC_CHG_SHIFT		6
+#define RT9873A_REG_INTM1_OTP_SHIFT		7
+#define RT9873A_REG_INTM1_ATTACH_MASK		(0x1 << RT9873A_REG_INTM1_ATTACH_SHIFT)
+#define RT9873A_REG_INTM1_DETACH_MASK		(0x1 <<  RT9873A_REG_INTM1_DETACH_SHIFT)
+#define RT9873A_REG_INTM1_CHGDET_MASK		(0x1 <<  RT9873A_REG_INTM1_CHGDET_SHIFT)
+#define RT9873A_REG_INTM1_DCD_T_MASK		(0x1 <<  RT9873A_REG_INTM1_DCD_T_SHIFT)
+#define RT9873A_REG_INTM1_OVP_MASK		(0x1 <<  RT9873A_REG_INTM1_OVP_SHIFT)
+#define RT9873A_REG_INTM1_CONNECT_MASK		(0x1 <<  RT9873A_REG_INTM1_CONNECT_SHIFT)
+#define RT9873A_REG_INTM1_ADC_CHG_MASK		(0x1 <<  RT9873A_REG_INTM1_ADC_CHG_SHIFT)
+#define RT9873A_REG_INTM1_OTP_MASK		(0x1 <<  RT9873A_REG_INTM1_OTP_SHIFT)
+
+#define RT9873A_REG_INTM2_UVLO_SHIFT		1
+#define RT9873A_REG_INTM2_POR_SHIFT		2
+#define RT9873A_REG_INTM2_OTP_FET_SHIFT		3
+#define RT9873A_REG_INTM2_OVP_FET_SHIFT		4
+#define RT9873A_REG_INTM2_OCP_LATCH_SHIFT	5
+#define RT9873A_REG_INTM2_OCP_SHIFT		6
+#define RT9873A_REG_INTM2_OVP_OCP_SHIFT		7
+#define RT9873A_REG_INTM2_UVLO_MASK		(0x1 << RT9873A_REG_INTM2_UVLO_SHIFT)
+#define RT9873A_REG_INTM2_POR_MASK		(0x1 <<  RT9873A_REG_INTM2_POR_SHIFT)
+#define RT9873A_REG_INTM2_OTP_FET_MASK		(0x1 <<  RT9873A_REG_INTM2_OTP_FET_SHIFT)
+#define RT9873A_REG_INTM2_OVP_FET_MASK		(0x1 <<  RT9873A_REG_INTM2_OVP_FET_SHIFT)
+#define RT9873A_REG_INTM2_OCP_LATCH_MASK	(0x1 <<  RT9873A_REG_INTM2_OCP_LATCH_SHIFT)
+#define RT9873A_REG_INTM2_OCP_MASK		(0x1 <<  RT9873A_REG_INTM2_OCP_SHIFT)
+#define RT9873A_REG_INTM2_OVP_OCP_MASK		(0x1 <<  RT9873A_REG_INTM2_OVP_OCP_SHIFT)
+
+#define RT8973A_REG_ADC_SHIFT			0
+#define RT8973A_REG_ADC_MASK			(0x1f << RT8973A_REG_ADC_SHIFT)
+
+#define RT8973A_REG_DEV1_OTG_SHIFT		0
+#define RT8973A_REG_DEV1_SDP_SHIFT		2
+#define RT8973A_REG_DEV1_UART_SHIFT		3
+#define RT8973A_REG_DEV1_CAR_KIT_TYPE1_SHIFT	4
+#define RT8973A_REG_DEV1_CDPORT_SHIFT		5
+#define RT8973A_REG_DEV1_DCPORT_SHIFT		6
+#define RT8973A_REG_DEV1_OTG_MASK		(0x1 << RT8973A_REG_DEV1_OTG_SHIFT)
+#define RT8973A_REG_DEV1_SDP_MASK		(0x1 << RT8973A_REG_DEV1_SDP_SHIFT)
+#define RT8973A_REG_DEV1_UART_MASK		(0x1 << RT8973A_REG_DEV1_UART_SHIFT)
+#define RT8973A_REG_DEV1_CAR_KIT_TYPE1_MASK	(0x1 << RT8973A_REG_DEV1_CAR_KIT_TYPE1_SHIFT)
+#define RT8973A_REG_DEV1_CDPORT_MASK		(0x1 << RT8973A_REG_DEV1_CDPORT_SHIFT)
+#define RT8973A_REG_DEV1_DCPORT_MASK		(0x1 << RT8973A_REG_DEV1_DCPORT_SHIFT)
+#define RT8973A_REG_DEV1_USB_MASK		(RT8973A_REG_DEV1_SDP_MASK \
+						| RT8973A_REG_DEV1_CDPORT_MASK)
+
+#define RT8973A_REG_DEV2_JIG_USB_ON_SHIFT	0
+#define RT8973A_REG_DEV2_JIG_USB_OFF_SHIFT	1
+#define RT8973A_REG_DEV2_JIG_UART_ON_SHIFT	2
+#define RT8973A_REG_DEV2_JIG_UART_OFF_SHIFT	3
+#define RT8973A_REG_DEV2_JIG_USB_ON_MASK	(0x1 << RT8973A_REG_DEV2_JIG_USB_ON_SHIFT)
+#define RT8973A_REG_DEV2_JIG_USB_OFF_MASK	(0x1 << RT8973A_REG_DEV2_JIG_USB_OFF_SHIFT)
+#define RT8973A_REG_DEV2_JIG_UART_ON_MASK	(0x1 << RT8973A_REG_DEV2_JIG_UART_ON_SHIFT)
+#define RT8973A_REG_DEV2_JIG_UART_OFF_MASK	(0x1 << RT8973A_REG_DEV2_JIG_UART_OFF_SHIFT)
+
+#define RT8973A_REG_MANUAL_SW1_DP_SHIFT		2
+#define RT8973A_REG_MANUAL_SW1_DM_SHIFT		5
+#define RT8973A_REG_MANUAL_SW1_DP_MASK		(0x7 << RT8973A_REG_MANUAL_SW1_DP_SHIFT)
+#define RT8973A_REG_MANUAL_SW1_DM_MASK		(0x7 << RT8973A_REG_MANUAL_SW1_DM_SHIFT)
+#define DM_DP_CON_SWITCH_OPEN			0x0
+#define DM_DP_CON_SWITCH_USB			0x1
+#define DM_DP_CON_SWITCH_UART			0x3
+#define DM_DP_SWITCH_OPEN			((DM_DP_CON_SWITCH_OPEN << RT8973A_REG_MANUAL_SW1_DP_SHIFT) \
+						| (DM_DP_CON_SWITCH_OPEN << RT8973A_REG_MANUAL_SW1_DM_SHIFT))
+#define DM_DP_SWITCH_USB			((DM_DP_CON_SWITCH_USB << RT8973A_REG_MANUAL_SW1_DP_SHIFT) \
+						| (DM_DP_CON_SWITCH_USB << RT8973A_REG_MANUAL_SW1_DM_SHIFT))
+#define DM_DP_SWITCH_UART			((DM_DP_CON_SWITCH_UART << RT8973A_REG_MANUAL_SW1_DP_SHIFT) \
+						| (DM_DP_CON_SWITCH_UART << RT8973A_REG_MANUAL_SW1_DM_SHIFT))
+
+#define RT8973A_REG_MANUAL_SW2_FET_ON_SHIFT	0
+#define RT8973A_REG_MANUAL_SW2_JIG_ON_SHIFT	2
+#define RT8973A_REG_MANUAL_SW2_BOOT_SW_SHIFT	3
+#define RT8973A_REG_MANUAL_SW2_FET_ON_MASK	(0x1 << RT8973A_REG_MANUAL_SW2_FET_ON_SHIFT)
+#define RT8973A_REG_MANUAL_SW2_JIG_ON_MASK	(0x1 << RT8973A_REG_MANUAL_SW2_JIG_ON_SHIFT)
+#define RT8973A_REG_MANUAL_SW2_BOOT_SW_MASK	(0x1 << RT8973A_REG_MANUAL_SW2_BOOT_SW_SHIFT)
+#define RT8973A_REG_MANUAL_SW2_FET_ON		0
+#define RT8973A_REG_MANUAL_SW2_FET_OFF		0x1
+#define RT8973A_REG_MANUAL_SW2_JIG_OFF		0
+#define RT8973A_REG_MANUAL_SW2_JIG_ON		0x1
+#define RT8973A_REG_MANUAL_SW2_BOOT_SW_ON	0
+#define RT8973A_REG_MANUAL_SW2_BOOT_SW_OFF	0x1
+
+#define RT8973A_REG_RESET_SHIFT			0
+#define RT8973A_REG_RESET_MASK			(0x1 << RT8973A_REG_RESET_SHIFT)
+#define RT8973A_REG_RESET			0x1
+
+/* RT8973A Interrupts */
+enum rt8973a_irq {
+	/* Interrupt1*/
+	RT8973A_INT1_ATTACH,
+	RT8973A_INT1_DETACH,
+	RT8973A_INT1_CHGDET,
+	RT8973A_INT1_DCD_T,
+	RT8973A_INT1_OVP,
+	RT8973A_INT1_CONNECT,
+	RT8973A_INT1_ADC_CHG,
+	RT8973A_INT1_OTP,
+
+	/* Interrupt2*/
+	RT8973A_INT2_UVLO,
+	RT8973A_INT2_POR,
+	RT8973A_INT2_OTP_FET,
+	RT8973A_INT2_OVP_FET,
+	RT8973A_INT2_OCP_LATCH,
+	RT8973A_INT2_OCP,
+	RT8973A_INT2_OVP_OCP,
+
+	RT8973A_NUM,
+};
+
+#define RT8973A_INT1_ATTACH_MASK		BIT(0)
+#define RT8973A_INT1_DETACH_MASK		BIT(1)
+#define RT8973A_INT1_CHGDET_MASK		BIT(2)
+#define RT8973A_INT1_DCD_T_MASK			BIT(3)
+#define RT8973A_INT1_OVP_MASK			BIT(4)
+#define RT8973A_INT1_CONNECT_MASK		BIT(5)
+#define RT8973A_INT1_ADC_CHG_MASK		BIT(6)
+#define RT8973A_INT1_OTP_MASK			BIT(7)
+#define RT8973A_INT2_UVLOT_MASK			BIT(0)
+#define RT8973A_INT2_POR_MASK			BIT(1)
+#define RT8973A_INT2_OTP_FET_MASK		BIT(2)
+#define RT8973A_INT2_OVP_FET_MASK		BIT(3)
+#define RT8973A_INT2_OCP_LATCH_MASK		BIT(4)
+#define RT8973A_INT2_OCP_MASK			BIT(5)
+#define RT8973A_INT2_OVP_OCP_MASK		BIT(6)
+
+#endif /*  __LINUX_EXTCON_RT8973A_H */