| /* |
| * mmap engine |
| * |
| * IO engine that reads/writes from files by doing memcpy to/from |
| * a memory mapped region of the file. |
| * |
| */ |
| #include <stdio.h> |
| #include <stdlib.h> |
| #include <unistd.h> |
| #include <errno.h> |
| #include <assert.h> |
| #include <sys/mman.h> |
| |
| #include "../fio.h" |
| |
| static int fio_mmapio_queue(struct thread_data *td, struct io_u *io_u) |
| { |
| struct fio_file *f = io_u->file; |
| unsigned long long real_off = io_u->offset - f->file_offset; |
| |
| fio_ro_check(td, io_u); |
| |
| if (io_u->ddir == DDIR_READ) |
| memcpy(io_u->xfer_buf, f->mmap + real_off, io_u->xfer_buflen); |
| else if (io_u->ddir == DDIR_WRITE) |
| memcpy(f->mmap + real_off, io_u->xfer_buf, io_u->xfer_buflen); |
| else if (io_u->ddir == DDIR_SYNC) { |
| size_t len = (f->io_size + page_size - 1) & ~page_mask; |
| |
| if (msync(f->mmap, len, MS_SYNC)) { |
| io_u->error = errno; |
| td_verror(td, io_u->error, "msync"); |
| } |
| } |
| |
| /* |
| * not really direct, but should drop the pages from the cache |
| */ |
| if (td->o.odirect && io_u->ddir != DDIR_SYNC) { |
| size_t len = (io_u->xfer_buflen + page_size - 1) & ~page_mask; |
| unsigned long long off = real_off & ~page_mask; |
| |
| if (msync(f->mmap + off, len, MS_SYNC) < 0) { |
| io_u->error = errno; |
| td_verror(td, io_u->error, "msync"); |
| } |
| if (madvise(f->mmap + off, len, MADV_DONTNEED) < 0) { |
| io_u->error = errno; |
| td_verror(td, io_u->error, "madvise"); |
| } |
| } |
| |
| return FIO_Q_COMPLETED; |
| } |
| |
| static int fio_mmapio_open(struct thread_data *td, struct fio_file *f) |
| { |
| int ret, flags; |
| |
| ret = generic_open_file(td, f); |
| if (ret) |
| return ret; |
| |
| /* |
| * for size checkup, don't mmap anything. |
| */ |
| if (!f->io_size) |
| return 0; |
| |
| if (td_rw(td)) |
| flags = PROT_READ | PROT_WRITE; |
| else if (td_write(td)) { |
| flags = PROT_WRITE; |
| |
| if (td->o.verify != VERIFY_NONE) |
| flags |= PROT_READ; |
| } else |
| flags = PROT_READ; |
| |
| f->mmap = mmap(NULL, f->io_size, flags, MAP_SHARED, f->fd, f->file_offset); |
| if (f->mmap == MAP_FAILED) { |
| f->mmap = NULL; |
| td_verror(td, errno, "mmap"); |
| goto err; |
| } |
| |
| if (file_invalidate_cache(td, f)) |
| goto err; |
| |
| if (!td_random(td)) { |
| if (madvise(f->mmap, f->io_size, MADV_SEQUENTIAL) < 0) { |
| td_verror(td, errno, "madvise"); |
| goto err; |
| } |
| } else { |
| if (madvise(f->mmap, f->io_size, MADV_RANDOM) < 0) { |
| td_verror(td, errno, "madvise"); |
| goto err; |
| } |
| } |
| |
| return 0; |
| |
| err: |
| td->io_ops->close_file(td, f); |
| return 1; |
| } |
| |
| static int fio_mmapio_close(struct thread_data fio_unused *td, |
| struct fio_file *f) |
| { |
| int ret = 0, ret2; |
| |
| if (f->mmap) { |
| if (munmap(f->mmap, f->io_size) < 0) |
| ret = errno; |
| |
| f->mmap = NULL; |
| } |
| |
| ret2 = generic_close_file(td, f); |
| if (!ret && ret2) |
| ret = ret2; |
| |
| return ret; |
| } |
| |
| static struct ioengine_ops ioengine = { |
| .name = "mmap", |
| .version = FIO_IOOPS_VERSION, |
| .queue = fio_mmapio_queue, |
| .open_file = fio_mmapio_open, |
| .close_file = fio_mmapio_close, |
| .flags = FIO_SYNCIO | FIO_NOEXTEND, |
| }; |
| |
| static void fio_init fio_mmapio_register(void) |
| { |
| register_ioengine(&ioengine); |
| } |
| |
| static void fio_exit fio_mmapio_unregister(void) |
| { |
| unregister_ioengine(&ioengine); |
| } |