[PATCH RFC PKS/PMEM 35/58] fs: Utilize new kmap_thread()

From: ira . weiny
Date: Fri Oct 09 2020 - 16:02:05 EST


From: Ira Weiny <ira.weiny@xxxxxxxxx>

These kmap() calls are localized to a single thread. To avoid the over
head of global PKRS updates use the new kmap_thread() call.

Cc: Alexander Viro <viro@xxxxxxxxxxxxxxxxxx>
Cc: Jens Axboe <axboe@xxxxxxxxx>
Signed-off-by: Ira Weiny <ira.weiny@xxxxxxxxx>
---
fs/aio.c | 4 ++--
fs/binfmt_elf.c | 4 ++--
fs/binfmt_elf_fdpic.c | 4 ++--
fs/exec.c | 10 +++++-----
fs/io_uring.c | 4 ++--
fs/splice.c | 4 ++--
6 files changed, 15 insertions(+), 15 deletions(-)

diff --git a/fs/aio.c b/fs/aio.c
index d5ec30385566..27f95996d25f 100644
--- a/fs/aio.c
+++ b/fs/aio.c
@@ -1223,10 +1223,10 @@ static long aio_read_events_ring(struct kioctx *ctx,
avail = min(avail, nr - ret);
avail = min_t(long, avail, AIO_EVENTS_PER_PAGE - pos);

- ev = kmap(page);
+ ev = kmap_thread(page);
copy_ret = copy_to_user(event + ret, ev + pos,
sizeof(*ev) * avail);
- kunmap(page);
+ kunmap_thread(page);

if (unlikely(copy_ret)) {
ret = -EFAULT;
diff --git a/fs/binfmt_elf.c b/fs/binfmt_elf.c
index 13d053982dd7..1a332ef1ae03 100644
--- a/fs/binfmt_elf.c
+++ b/fs/binfmt_elf.c
@@ -2430,9 +2430,9 @@ static int elf_core_dump(struct coredump_params *cprm)

page = get_dump_page(addr);
if (page) {
- void *kaddr = kmap(page);
+ void *kaddr = kmap_thread(page);
stop = !dump_emit(cprm, kaddr, PAGE_SIZE);
- kunmap(page);
+ kunmap_thread(page);
put_page(page);
} else
stop = !dump_skip(cprm, PAGE_SIZE);
diff --git a/fs/binfmt_elf_fdpic.c b/fs/binfmt_elf_fdpic.c
index 50f845702b92..8fbe188e0fdd 100644
--- a/fs/binfmt_elf_fdpic.c
+++ b/fs/binfmt_elf_fdpic.c
@@ -1542,9 +1542,9 @@ static bool elf_fdpic_dump_segments(struct coredump_params *cprm)
bool res;
struct page *page = get_dump_page(addr);
if (page) {
- void *kaddr = kmap(page);
+ void *kaddr = kmap_thread(page);
res = dump_emit(cprm, kaddr, PAGE_SIZE);
- kunmap(page);
+ kunmap_thread(page);
put_page(page);
} else {
res = dump_skip(cprm, PAGE_SIZE);
diff --git a/fs/exec.c b/fs/exec.c
index a91003e28eaa..3948b8511e3a 100644
--- a/fs/exec.c
+++ b/fs/exec.c
@@ -575,11 +575,11 @@ static int copy_strings(int argc, struct user_arg_ptr argv,

if (kmapped_page) {
flush_kernel_dcache_page(kmapped_page);
- kunmap(kmapped_page);
+ kunmap_thread(kmapped_page);
put_arg_page(kmapped_page);
}
kmapped_page = page;
- kaddr = kmap(kmapped_page);
+ kaddr = kmap_thread(kmapped_page);
kpos = pos & PAGE_MASK;
flush_arg_page(bprm, kpos, kmapped_page);
}
@@ -593,7 +593,7 @@ static int copy_strings(int argc, struct user_arg_ptr argv,
out:
if (kmapped_page) {
flush_kernel_dcache_page(kmapped_page);
- kunmap(kmapped_page);
+ kunmap_thread(kmapped_page);
put_arg_page(kmapped_page);
}
return ret;
@@ -871,11 +871,11 @@ int transfer_args_to_stack(struct linux_binprm *bprm,

for (index = MAX_ARG_PAGES - 1; index >= stop; index--) {
unsigned int offset = index == stop ? bprm->p & ~PAGE_MASK : 0;
- char *src = kmap(bprm->page[index]) + offset;
+ char *src = kmap_thread(bprm->page[index]) + offset;
sp -= PAGE_SIZE - offset;
if (copy_to_user((void *) sp, src, PAGE_SIZE - offset) != 0)
ret = -EFAULT;
- kunmap(bprm->page[index]);
+ kunmap_thread(bprm->page[index]);
if (ret)
goto out;
}
diff --git a/fs/io_uring.c b/fs/io_uring.c
index aae0ef2ec34d..f59bb079822d 100644
--- a/fs/io_uring.c
+++ b/fs/io_uring.c
@@ -2903,7 +2903,7 @@ static ssize_t loop_rw_iter(int rw, struct file *file, struct kiocb *kiocb,
iovec = iov_iter_iovec(iter);
} else {
/* fixed buffers import bvec */
- iovec.iov_base = kmap(iter->bvec->bv_page)
+ iovec.iov_base = kmap_thread(iter->bvec->bv_page)
+ iter->iov_offset;
iovec.iov_len = min(iter->count,
iter->bvec->bv_len - iter->iov_offset);
@@ -2918,7 +2918,7 @@ static ssize_t loop_rw_iter(int rw, struct file *file, struct kiocb *kiocb,
}

if (iov_iter_is_bvec(iter))
- kunmap(iter->bvec->bv_page);
+ kunmap_thread(iter->bvec->bv_page);

if (nr < 0) {
if (!ret)
diff --git a/fs/splice.c b/fs/splice.c
index ce75aec52274..190c4d218c30 100644
--- a/fs/splice.c
+++ b/fs/splice.c
@@ -815,9 +815,9 @@ static int write_pipe_buf(struct pipe_inode_info *pipe, struct pipe_buffer *buf,
void *data;
loff_t tmp = sd->pos;

- data = kmap(buf->page);
+ data = kmap_thread(buf->page);
ret = __kernel_write(sd->u.file, data + buf->offset, sd->len, &tmp);
- kunmap(buf->page);
+ kunmap_thread(buf->page);

return ret;
}
--
2.28.0.rc0.12.gb6a658bd00c9