From aa43457799f715d76cb77342baab0615877e2b8a Mon Sep 17 00:00:00 2001 From: Adam Manzanares Date: Tue, 22 May 2018 10:52:17 -0700 Subject: block: add ioprio_check_cap function Aio per command iopriority support introduces a second interface between userland and the kernel capable of passing iopriority. The aio interface also needs the ability to verify that the submitting context has sufficient privileges to submit IOPRIO_RT commands. This patch creates the ioprio_check_cap function to be used by the ioprio_set system call and also by the aio interface. Signed-off-by: Adam Manzanares Reviewed-by: Christoph Hellwig Reviewed-by: Jeff Moyer Signed-off-by: Al Viro --- include/linux/ioprio.h | 2 ++ 1 file changed, 2 insertions(+) (limited to 'include') diff --git a/include/linux/ioprio.h b/include/linux/ioprio.h index 627efac73e6d..4a28cec49ec3 100644 --- a/include/linux/ioprio.h +++ b/include/linux/ioprio.h @@ -77,4 +77,6 @@ extern int ioprio_best(unsigned short aprio, unsigned short bprio); extern int set_task_ioprio(struct task_struct *task, int ioprio); +extern int ioprio_check_cap(int ioprio); + #endif -- cgit v1.2.3 From fc28724d67c90ff48b976e0687caf79993160bed Mon Sep 17 00:00:00 2001 From: Adam Manzanares Date: Tue, 22 May 2018 10:52:18 -0700 Subject: fs: Convert kiocb rw_hint from enum to u16 In order to avoid kiocb bloat for per command iopriority support, rw_hint is converted from enum to a u16. Added a guard around ki_hint assignment. Signed-off-by: Adam Manzanares Signed-off-by: Al Viro --- fs/aio.c | 2 +- include/linux/fs.h | 13 +++++++++++-- 2 files changed, 12 insertions(+), 3 deletions(-) (limited to 'include') diff --git a/fs/aio.c b/fs/aio.c index b850e92ee0d5..33299ece7540 100644 --- a/fs/aio.c +++ b/fs/aio.c @@ -1434,7 +1434,7 @@ static int aio_prep_rw(struct kiocb *req, struct iocb *iocb) req->ki_flags = iocb_flags(req->ki_filp); if (iocb->aio_flags & IOCB_FLAG_RESFD) req->ki_flags |= IOCB_EVENTFD; - req->ki_hint = file_write_hint(req->ki_filp); + req->ki_hint = ki_hint_validate(file_write_hint(req->ki_filp)); ret = kiocb_set_rw_flags(req, iocb->aio_rw_flags); if (unlikely(ret)) fput(req->ki_filp); diff --git a/include/linux/fs.h b/include/linux/fs.h index 4b6045ebb2f2..b432fc3feb93 100644 --- a/include/linux/fs.h +++ b/include/linux/fs.h @@ -299,7 +299,7 @@ struct kiocb { void (*ki_complete)(struct kiocb *iocb, long ret, long ret2); void *private; int ki_flags; - enum rw_hint ki_hint; + u16 ki_hint; } __randomize_layout; static inline bool is_sync_kiocb(struct kiocb *kiocb) @@ -1929,12 +1929,21 @@ static inline enum rw_hint file_write_hint(struct file *file) static inline int iocb_flags(struct file *file); +static inline u16 ki_hint_validate(enum rw_hint hint) +{ + typeof(((struct kiocb *)0)->ki_hint) max_hint = -1; + + if (hint <= max_hint) + return hint; + return 0; +} + static inline void init_sync_kiocb(struct kiocb *kiocb, struct file *filp) { *kiocb = (struct kiocb) { .ki_filp = filp, .ki_flags = iocb_flags(filp), - .ki_hint = file_write_hint(filp), + .ki_hint = ki_hint_validate(file_write_hint(filp)), }; } -- cgit v1.2.3 From d9a08a9e616beeccdbd0e7262b7225ffdfa49e92 Mon Sep 17 00:00:00 2001 From: Adam Manzanares Date: Tue, 22 May 2018 10:52:19 -0700 Subject: fs: Add aio iopriority support This is the per-I/O equivalent of the ioprio_set system call. When IOCB_FLAG_IOPRIO is set on the iocb aio_flags field, then we set the newly added kiocb ki_ioprio field to the value in the iocb aio_reqprio field. This patch depends on block: add ioprio_check_cap function. Signed-off-by: Adam Manzanares Reviewed-by: Jeff Moyer Reviewed-by: Christoph Hellwig Signed-off-by: Al Viro --- drivers/block/loop.c | 3 +++ fs/aio.c | 16 ++++++++++++++++ include/linux/fs.h | 3 +++ include/uapi/linux/aio_abi.h | 1 + 4 files changed, 23 insertions(+) (limited to 'include') diff --git a/drivers/block/loop.c b/drivers/block/loop.c index 5d4e31655d96..dd98dfd97f5e 100644 --- a/drivers/block/loop.c +++ b/drivers/block/loop.c @@ -76,6 +76,8 @@ #include #include #include +#include + #include "loop.h" #include @@ -559,6 +561,7 @@ static int lo_rw_aio(struct loop_device *lo, struct loop_cmd *cmd, cmd->iocb.ki_filp = file; cmd->iocb.ki_complete = lo_rw_aio_complete; cmd->iocb.ki_flags = IOCB_DIRECT; + cmd->iocb.ki_ioprio = IOPRIO_PRIO_VALUE(IOPRIO_CLASS_NONE, 0); if (cmd->css) kthread_associate_blkcg(cmd->css); diff --git a/fs/aio.c b/fs/aio.c index 33299ece7540..9527ededa669 100644 --- a/fs/aio.c +++ b/fs/aio.c @@ -1435,6 +1435,22 @@ static int aio_prep_rw(struct kiocb *req, struct iocb *iocb) if (iocb->aio_flags & IOCB_FLAG_RESFD) req->ki_flags |= IOCB_EVENTFD; req->ki_hint = ki_hint_validate(file_write_hint(req->ki_filp)); + if (iocb->aio_flags & IOCB_FLAG_IOPRIO) { + /* + * If the IOCB_FLAG_IOPRIO flag of aio_flags is set, then + * aio_reqprio is interpreted as an I/O scheduling + * class and priority. + */ + ret = ioprio_check_cap(iocb->aio_reqprio); + if (ret) { + pr_debug("aio ioprio check cap error\n"); + return -EINVAL; + } + + req->ki_ioprio = iocb->aio_reqprio; + } else + req->ki_ioprio = IOPRIO_PRIO_VALUE(IOPRIO_CLASS_NONE, 0); + ret = kiocb_set_rw_flags(req, iocb->aio_rw_flags); if (unlikely(ret)) fput(req->ki_filp); diff --git a/include/linux/fs.h b/include/linux/fs.h index b432fc3feb93..eef9334b26d1 100644 --- a/include/linux/fs.h +++ b/include/linux/fs.h @@ -36,6 +36,7 @@ #include #include #include +#include #include #include @@ -300,6 +301,7 @@ struct kiocb { void *private; int ki_flags; u16 ki_hint; + u16 ki_ioprio; /* See linux/ioprio.h */ } __randomize_layout; static inline bool is_sync_kiocb(struct kiocb *kiocb) @@ -1944,6 +1946,7 @@ static inline void init_sync_kiocb(struct kiocb *kiocb, struct file *filp) .ki_filp = filp, .ki_flags = iocb_flags(filp), .ki_hint = ki_hint_validate(file_write_hint(filp)), + .ki_ioprio = IOPRIO_PRIO_VALUE(IOPRIO_CLASS_NONE, 0), }; } diff --git a/include/uapi/linux/aio_abi.h b/include/uapi/linux/aio_abi.h index ed0185945bb2..75846164290e 100644 --- a/include/uapi/linux/aio_abi.h +++ b/include/uapi/linux/aio_abi.h @@ -53,6 +53,7 @@ enum { * is valid. */ #define IOCB_FLAG_RESFD (1 << 0) +#define IOCB_FLAG_IOPRIO (1 << 1) /* read() from /dev/aio returns these structures. */ struct io_event { -- cgit v1.2.3 From b0966e7b894035dba6710aa4e9f18d7a3a3d5b22 Mon Sep 17 00:00:00 2001 From: Adam Manzanares Date: Mon, 4 Jun 2018 10:59:56 -0700 Subject: fs: aio ioprio add explicit block layer dependence Previously, the ioprio_check_cap function was only defined when CONFIG_BLOCK was set. Make this relationship explicit and add a stub for !CONFIG_BLOCK. Signed-off-by: Adam Manzanares Signed-off-by: Al Viro --- include/linux/ioprio.h | 7 +++++++ 1 file changed, 7 insertions(+) (limited to 'include') diff --git a/include/linux/ioprio.h b/include/linux/ioprio.h index 4a28cec49ec3..9e30ed6443db 100644 --- a/include/linux/ioprio.h +++ b/include/linux/ioprio.h @@ -77,6 +77,13 @@ extern int ioprio_best(unsigned short aprio, unsigned short bprio); extern int set_task_ioprio(struct task_struct *task, int ioprio); +#ifdef CONFIG_BLOCK extern int ioprio_check_cap(int ioprio); +#else +static inline int ioprio_check_cap(int ioprio) +{ + return -ENOTBLK; +} +#endif /* CONFIG_BLOCK */ #endif -- cgit v1.2.3