diff options
author | Linus Torvalds <torvalds@linux-foundation.org> | 2013-05-07 20:49:51 -0700 |
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committer | Linus Torvalds <torvalds@linux-foundation.org> | 2013-05-07 20:49:51 -0700 |
commit | 5af43c24ca59a448c9312dd4a4a51d27ec3b9a73 (patch) | |
tree | 65288caabc91fc04242acace38789a6dd5b86ed4 /drivers/char/mem.c | |
parent | 9affd6becbfb2c3f0d04e554bb87234761b37aba (diff) | |
parent | a27bb332c04cec8c4afd7912df0dc7890db27560 (diff) |
Merge branch 'akpm' (incoming from Andrew)
Merge more incoming from Andrew Morton:
- Various fixes which were stalled or which I picked up recently
- A large rotorooting of the AIO code. Allegedly to improve
performance but I don't really have good performance numbers (I might
have lost the email) and I can't raise Kent today. I held this out
of 3.9 and we could give it another cycle if it's all too late/scary.
I ended up taking only the first two thirds of the AIO rotorooting. I
left the percpu parts and the batch completion for later. - Linus
* emailed patches from Andrew Morton <akpm@linux-foundation.org>: (33 commits)
aio: don't include aio.h in sched.h
aio: kill ki_retry
aio: kill ki_key
aio: give shared kioctx fields their own cachelines
aio: kill struct aio_ring_info
aio: kill batch allocation
aio: change reqs_active to include unreaped completions
aio: use cancellation list lazily
aio: use flush_dcache_page()
aio: make aio_read_evt() more efficient, convert to hrtimers
wait: add wait_event_hrtimeout()
aio: refcounting cleanup
aio: make aio_put_req() lockless
aio: do fget() after aio_get_req()
aio: dprintk() -> pr_debug()
aio: move private stuff out of aio.h
aio: add kiocb_cancel()
aio: kill return value of aio_complete()
char: add aio_{read,write} to /dev/{null,zero}
aio: remove retry-based AIO
...
Diffstat (limited to 'drivers/char/mem.c')
-rw-r--r-- | drivers/char/mem.c | 36 |
1 files changed, 36 insertions, 0 deletions
diff --git a/drivers/char/mem.c b/drivers/char/mem.c index 2c644afbcdd..1ccbe9482fa 100644 --- a/drivers/char/mem.c +++ b/drivers/char/mem.c @@ -28,6 +28,7 @@ #include <linux/pfn.h> #include <linux/export.h> #include <linux/io.h> +#include <linux/aio.h> #include <asm/uaccess.h> @@ -627,6 +628,18 @@ static ssize_t write_null(struct file *file, const char __user *buf, return count; } +static ssize_t aio_read_null(struct kiocb *iocb, const struct iovec *iov, + unsigned long nr_segs, loff_t pos) +{ + return 0; +} + +static ssize_t aio_write_null(struct kiocb *iocb, const struct iovec *iov, + unsigned long nr_segs, loff_t pos) +{ + return iov_length(iov, nr_segs); +} + static int pipe_to_null(struct pipe_inode_info *info, struct pipe_buffer *buf, struct splice_desc *sd) { @@ -670,6 +683,24 @@ static ssize_t read_zero(struct file *file, char __user *buf, return written ? written : -EFAULT; } +static ssize_t aio_read_zero(struct kiocb *iocb, const struct iovec *iov, + unsigned long nr_segs, loff_t pos) +{ + size_t written = 0; + unsigned long i; + ssize_t ret; + + for (i = 0; i < nr_segs; i++) { + ret = read_zero(iocb->ki_filp, iov[i].iov_base, iov[i].iov_len, + &pos); + if (ret < 0) + break; + written += ret; + } + + return written ? written : -EFAULT; +} + static int mmap_zero(struct file *file, struct vm_area_struct *vma) { #ifndef CONFIG_MMU @@ -738,6 +769,7 @@ static int open_port(struct inode *inode, struct file *filp) #define full_lseek null_lseek #define write_zero write_null #define read_full read_zero +#define aio_write_zero aio_write_null #define open_mem open_port #define open_kmem open_mem #define open_oldmem open_mem @@ -766,6 +798,8 @@ static const struct file_operations null_fops = { .llseek = null_lseek, .read = read_null, .write = write_null, + .aio_read = aio_read_null, + .aio_write = aio_write_null, .splice_write = splice_write_null, }; @@ -782,6 +816,8 @@ static const struct file_operations zero_fops = { .llseek = zero_lseek, .read = read_zero, .write = write_zero, + .aio_read = aio_read_zero, + .aio_write = aio_write_zero, .mmap = mmap_zero, }; |