* Lustre Lite I/O page cache routines for the 2.5/2.6 kernel version
*/
+#include <linux/buffer_head.h>
+#include <linux/errno.h>
+#include <linux/fs.h>
#include <linux/kernel.h>
#include <linux/mm.h>
+#include <linux/mpage.h>
+#include <linux/pagemap.h>
#include <linux/string.h>
-#include <linux/stat.h>
-#include <linux/errno.h>
#include <linux/unistd.h>
-#include <asm/uaccess.h>
+#include <linux/writeback.h>
#ifdef HAVE_MIGRATE_H
#include <linux/migrate.h>
#elif defined(HAVE_MIGRATE_MODE_H)
#include <linux/migrate_mode.h>
#endif
-#include <linux/fs.h>
-#include <linux/buffer_head.h>
-#include <linux/mpage.h>
-#include <linux/writeback.h>
-#include <linux/stat.h>
-#include <asm/uaccess.h>
-#include <linux/mm.h>
-#include <linux/pagemap.h>
#define DEBUG_SUBSYSTEM S_LLITE
if (obj == NULL)
return 1;
- /* 1 for caller, 1 for cl_page and 1 for page cache */
- if (page_count(vmpage) > 3)
- return 0;
-
page = cl_vmpage_page(vmpage, obj);
if (page == NULL)
return 1;
return result;
}
-#define MAX_DIRECTIO_SIZE 2*1024*1024*1024UL
+#if defined(HAVE_DIRECTIO_ITER) || defined(HAVE_IOV_ITER_RW) || \
+ defined(HAVE_DIRECTIO_2ARGS)
+#define HAVE_DIO_ITER 1
+#endif
-static ssize_t
-ll_direct_IO_seg(const struct lu_env *env, struct cl_io *io, int rw,
- struct inode *inode, size_t size, loff_t file_offset,
- struct page **pages, int page_count)
+/*
+ * ll_free_user_pages - tear down page struct array
+ * @pages: array of page struct pointers underlying target buffer
+ */
+static void ll_free_user_pages(struct page **pages, int npages)
{
- struct cl_page *clp;
- struct cl_2queue *queue;
- struct cl_object *obj = io->ci_obj;
int i;
- ssize_t rc = 0;
- size_t page_size = cl_page_size(obj);
- size_t orig_size = size;
- bool do_io;
- int io_pages = 0;
- ENTRY;
- queue = &io->ci_queue;
- cl_2queue_init(queue);
- for (i = 0; i < page_count; i++) {
- LASSERT(!(file_offset & (page_size - 1)));
- clp = cl_page_find(env, obj, cl_index(obj, file_offset),
- pages[i], CPT_TRANSIENT);
- if (IS_ERR(clp)) {
- rc = PTR_ERR(clp);
+ for (i = 0; i < npages; i++) {
+ if (!pages[i])
break;
- }
+ put_page(pages[i]);
+ }
- rc = cl_page_own(env, io, clp);
- if (rc) {
- LASSERT(clp->cp_state == CPS_FREEING);
- cl_page_put(env, clp);
- break;
- }
+#if defined(HAVE_DIO_ITER)
+ kvfree(pages);
+#else
+ OBD_FREE_LARGE(pages, npages * sizeof(*pages));
+#endif
+}
- do_io = true;
+static ssize_t ll_get_user_pages(int rw, struct iov_iter *iter,
+ struct page ***pages, ssize_t *npages,
+ size_t maxsize)
+{
+#if defined(HAVE_DIO_ITER)
+ size_t start;
+ size_t result;
- /* check the page type: if the page is a host page, then do
- * write directly
- */
- if (clp->cp_type == CPT_CACHEABLE) {
- struct page *vmpage = cl_page_vmpage(clp);
- struct page *src_page;
- struct page *dst_page;
- void *src;
- void *dst;
-
- src_page = (rw == WRITE) ? pages[i] : vmpage;
- dst_page = (rw == WRITE) ? vmpage : pages[i];
-
- src = ll_kmap_atomic(src_page, KM_USER0);
- dst = ll_kmap_atomic(dst_page, KM_USER1);
- memcpy(dst, src, min(page_size, size));
- ll_kunmap_atomic(dst, KM_USER1);
- ll_kunmap_atomic(src, KM_USER0);
-
- /* make sure page will be added to the transfer by
- * cl_io_submit()->...->vvp_page_prep_write().
- */
- if (rw == WRITE)
- set_page_dirty(vmpage);
-
- if (rw == READ) {
- /* do not issue the page for read, since it
- * may reread a ra page which has NOT uptodate
- * bit set.
- */
- cl_page_disown(env, io, clp);
- do_io = false;
- }
- }
+ /*
+ * iov_iter_get_pages_alloc() is introduced in 3.16 similar
+ * to HAVE_DIO_ITER.
+ */
+ result = iov_iter_get_pages_alloc(iter, pages, maxsize, &start);
+ if (result > 0)
+ *npages = DIV_ROUND_UP(result + start, PAGE_SIZE);
- if (likely(do_io)) {
- cl_2queue_add(queue, clp);
+ return result;
+#else
+ unsigned long addr;
+ size_t page_count;
+ size_t size;
+ long result;
- /*
- * Set page clip to tell transfer formation engine
- * that page has to be sent even if it is beyond KMS.
- */
- cl_page_clip(env, clp, 0, min(size, page_size));
+ if (!maxsize)
+ return 0;
- ++io_pages;
- }
+ if (!iter->nr_segs)
+ return 0;
- /* drop the reference count for cl_page_find */
- cl_page_put(env, clp);
- size -= page_size;
- file_offset += page_size;
+ addr = (unsigned long)iter->iov->iov_base + iter->iov_offset;
+ if (addr & ~PAGE_MASK)
+ return -EINVAL;
+
+ size = min_t(size_t, maxsize, iter->iov->iov_len);
+ page_count = (size + PAGE_SIZE - 1) >> PAGE_SHIFT;
+ OBD_ALLOC_LARGE(*pages, page_count * sizeof(**pages));
+ if (*pages == NULL)
+ return -ENOMEM;
+
+ down_read(¤t->mm->mmap_sem);
+ result = get_user_pages(current, current->mm, addr, page_count,
+ rw == READ, 0, *pages, NULL);
+ up_read(¤t->mm->mmap_sem);
+
+ if (unlikely(result != page_count)) {
+ ll_free_user_pages(*pages, page_count);
+ *pages = NULL;
+
+ if (result >= 0)
+ return -EFAULT;
+
+ return result;
}
+ *npages = page_count;
+
+ return size;
+#endif
+}
+
+/* iov_iter_alignment() is introduced in 3.16 similar to HAVE_DIO_ITER */
+#if defined(HAVE_DIO_ITER)
+static unsigned long ll_iov_iter_alignment(const struct iov_iter *i)
+{
+ return iov_iter_alignment(i);
+}
+#else /* copied from alignment_iovec() */
+static unsigned long ll_iov_iter_alignment(const struct iov_iter *i)
+{
+ const struct iovec *iov = i->iov;
+ unsigned long res;
+ size_t size = i->count;
+ size_t n;
+
+ if (!size)
+ return 0;
+
+ res = (unsigned long)iov->iov_base + i->iov_offset;
+ n = iov->iov_len - i->iov_offset;
+ if (n >= size)
+ return res | size;
- if (rc == 0 && io_pages) {
- rc = cl_io_submit_sync(env, io,
- rw == READ ? CRT_READ : CRT_WRITE,
- queue, 0);
+ size -= n;
+ res |= n;
+ while (size > (++iov)->iov_len) {
+ res |= (unsigned long)iov->iov_base | iov->iov_len;
+ size -= iov->iov_len;
}
- if (rc == 0)
- rc = orig_size;
+ res |= (unsigned long)iov->iov_base | size;
- cl_2queue_discard(env, io, queue);
- cl_2queue_disown(env, io, queue);
- cl_2queue_fini(env, queue);
- RETURN(rc);
+ return res;
+}
+#endif
+
+#ifndef HAVE_AIO_COMPLETE
+static inline void aio_complete(struct kiocb *iocb, ssize_t res, ssize_t res2)
+{
+ if (iocb->ki_complete)
+ iocb->ki_complete(iocb, res, res2);
+}
+#endif
+
+/** direct IO pages */
+struct ll_dio_pages {
+ struct cl_dio_aio *ldp_aio;
+ /*
+ * page array to be written. we don't support
+ * partial pages except the last one.
+ */
+ struct page **ldp_pages;
+ /** # of pages in the array. */
+ size_t ldp_count;
+ /* the file offset of the first page. */
+ loff_t ldp_file_offset;
+};
+
+static void ll_aio_end(const struct lu_env *env, struct cl_sync_io *anchor)
+{
+ struct cl_dio_aio *aio = container_of(anchor, typeof(*aio), cda_sync);
+ ssize_t ret = anchor->csi_sync_rc;
+
+ ENTRY;
+
+ /* release pages */
+ while (aio->cda_pages.pl_nr > 0) {
+ struct cl_page *page = cl_page_list_first(&aio->cda_pages);
+
+ cl_page_get(page);
+ cl_page_list_del(env, &aio->cda_pages, page);
+ cl_page_delete(env, page);
+ cl_page_put(env, page);
+ }
+
+ if (!is_sync_kiocb(aio->cda_iocb))
+ aio_complete(aio->cda_iocb, ret ?: aio->cda_bytes, 0);
+
+ EXIT;
+}
+
+static struct cl_dio_aio *ll_aio_alloc(struct kiocb *iocb)
+{
+ struct cl_dio_aio *aio;
+
+ OBD_ALLOC_PTR(aio);
+ if (aio != NULL) {
+ /*
+ * Hold one ref so that it won't be released until
+ * every pages is added.
+ */
+ cl_sync_io_init_notify(&aio->cda_sync, 1, is_sync_kiocb(iocb) ?
+ NULL : aio, ll_aio_end);
+ cl_page_list_init(&aio->cda_pages);
+ aio->cda_iocb = iocb;
+ }
+ return aio;
}
-/* ll_free_user_pages - tear down page struct array
- * @pages: array of page struct pointers underlying target buffer */
-static void ll_free_user_pages(struct page **pages, int npages, int do_dirty)
+static int
+ll_direct_rw_pages(const struct lu_env *env, struct cl_io *io, size_t size,
+ int rw, struct inode *inode, struct ll_dio_pages *pv)
{
+ struct cl_page *page;
+ struct cl_2queue *queue = &io->ci_queue;
+ struct cl_object *obj = io->ci_obj;
+ struct cl_sync_io *anchor = &pv->ldp_aio->cda_sync;
+ loff_t offset = pv->ldp_file_offset;
+ int io_pages = 0;
+ size_t page_size = cl_page_size(obj);
int i;
+ ssize_t rc = 0;
- for (i = 0; i < npages; i++) {
- if (pages[i] == NULL)
+ ENTRY;
+
+ cl_2queue_init(queue);
+ for (i = 0; i < pv->ldp_count; i++) {
+ LASSERT(!(offset & (PAGE_SIZE - 1)));
+ page = cl_page_find(env, obj, cl_index(obj, offset),
+ pv->ldp_pages[i], CPT_TRANSIENT);
+ if (IS_ERR(page)) {
+ rc = PTR_ERR(page);
break;
- if (do_dirty)
- set_page_dirty_lock(pages[i]);
- put_page(pages[i]);
+ }
+ LASSERT(page->cp_type == CPT_TRANSIENT);
+ rc = cl_page_own(env, io, page);
+ if (rc) {
+ cl_page_put(env, page);
+ break;
+ }
+
+ page->cp_sync_io = anchor;
+ cl_2queue_add(queue, page);
+ /*
+ * Set page clip to tell transfer formation engine
+ * that page has to be sent even if it is beyond KMS.
+ */
+ cl_page_clip(env, page, 0, min(size, page_size));
+ ++io_pages;
+
+ /* drop the reference count for cl_page_find */
+ cl_page_put(env, page);
+ offset += page_size;
+ size -= page_size;
+ }
+ if (rc == 0 && io_pages > 0) {
+ int iot = rw == READ ? CRT_READ : CRT_WRITE;
+
+ atomic_add(io_pages, &anchor->csi_sync_nr);
+ rc = cl_io_submit_rw(env, io, iot, queue);
+ if (rc == 0) {
+ cl_page_list_splice(&queue->c2_qout,
+ &pv->ldp_aio->cda_pages);
+ } else {
+ atomic_add(-queue->c2_qin.pl_nr,
+ &anchor->csi_sync_nr);
+ cl_page_list_for_each(page, &queue->c2_qin)
+ page->cp_sync_io = NULL;
+ }
+ /* handle partially submitted reqs */
+ if (queue->c2_qin.pl_nr > 0) {
+ CERROR(DFID " failed to submit %d dio pages: %zd\n",
+ PFID(lu_object_fid(&obj->co_lu)),
+ queue->c2_qin.pl_nr, rc);
+ if (rc == 0)
+ rc = -EIO;
+ }
}
-#if defined(HAVE_DIRECTIO_ITER) || defined(HAVE_IOV_ITER_RW)
- kvfree(pages);
-#else
- OBD_FREE_LARGE(pages, npages * sizeof(*pages));
-#endif
+ cl_2queue_discard(env, io, queue);
+ cl_2queue_disown(env, io, queue);
+ cl_2queue_fini(env, queue);
+ RETURN(rc);
}
#ifdef KMALLOC_MAX_SIZE
#define MAX_DIO_SIZE ((MAX_MALLOC / sizeof(struct brw_page) * PAGE_SIZE) & \
~(DT_MAX_BRW_SIZE - 1))
-#ifndef HAVE_IOV_ITER_RW
-# define iov_iter_rw(iter) rw
-#endif
-
-#if defined(HAVE_DIRECTIO_ITER) || defined(HAVE_IOV_ITER_RW)
static ssize_t
-ll_direct_IO(
-# ifndef HAVE_IOV_ITER_RW
- int rw,
-# endif
- struct kiocb *iocb, struct iov_iter *iter
-# ifndef HAVE_DIRECTIO_2ARGS
- , loff_t file_offset
-# endif
- )
+ll_direct_IO_impl(struct kiocb *iocb, struct iov_iter *iter, int rw)
{
-#ifdef HAVE_DIRECTIO_2ARGS
- loff_t file_offset = iocb->ki_pos;
-#endif
struct ll_cl_context *lcc;
const struct lu_env *env;
struct cl_io *io;
struct file *file = iocb->ki_filp;
struct inode *inode = file->f_mapping->host;
- ssize_t count = iov_iter_count(iter);
+ struct cl_dio_aio *aio;
+ size_t count = iov_iter_count(iter);
ssize_t tot_bytes = 0, result = 0;
- size_t size = MAX_DIO_SIZE;
+ loff_t file_offset = iocb->ki_pos;
/* Check EOF by ourselves */
- if (iov_iter_rw(iter) == READ && file_offset >= i_size_read(inode))
+ if (rw == READ && file_offset >= i_size_read(inode))
return 0;
+
/* FIXME: io smaller than PAGE_SIZE is broken on ia64 ??? */
if ((file_offset & ~PAGE_MASK) || (count & ~PAGE_MASK))
return -EINVAL;
MAX_DIO_SIZE >> PAGE_SHIFT);
/* Check that all user buffers are aligned as well */
- if (iov_iter_alignment(iter) & ~PAGE_MASK)
+ if (ll_iov_iter_alignment(iter) & ~PAGE_MASK)
return -EINVAL;
lcc = ll_cl_find(file);
io = lcc->lcc_io;
LASSERT(io != NULL);
+ aio = ll_aio_alloc(iocb);
+ if (!aio)
+ RETURN(-ENOMEM);
+
/* 0. Need locking between buffered and direct access. and race with
* size changing by concurrent truncates and writes.
* 1. Need inode mutex to operate transient pages.
*/
- if (iov_iter_rw(iter) == READ)
+ if (rw == READ)
inode_lock(inode);
while (iov_iter_count(iter)) {
+ struct ll_dio_pages pvec = { .ldp_aio = aio };
struct page **pages;
- size_t offs;
- count = min_t(size_t, iov_iter_count(iter), size);
- if (iov_iter_rw(iter) == READ) {
+ count = min_t(size_t, iov_iter_count(iter), MAX_DIO_SIZE);
+ if (rw == READ) {
if (file_offset >= i_size_read(inode))
break;
count = i_size_read(inode) - file_offset;
}
- result = iov_iter_get_pages_alloc(iter, &pages, count, &offs);
- if (likely(result > 0)) {
- int n = DIV_ROUND_UP(result + offs, PAGE_SIZE);
+ result = ll_get_user_pages(rw, iter, &pages,
+ &pvec.ldp_count, count);
+ if (unlikely(result <= 0))
+ GOTO(out, result);
- result = ll_direct_IO_seg(env, io, iov_iter_rw(iter),
- inode, result, file_offset,
- pages, n);
- ll_free_user_pages(pages, n,
- iov_iter_rw(iter) == READ);
+ count = result;
+ pvec.ldp_file_offset = file_offset;
+ pvec.ldp_pages = pages;
- }
- if (unlikely(result <= 0)) {
- /* If we can't allocate a large enough buffer
- * for the request, shrink it to a smaller
- * PAGE_SIZE multiple and try again.
- * We should always be able to kmalloc for a
- * page worth of page pointers = 4MB on i386. */
- if (result == -ENOMEM &&
- size > (PAGE_SIZE / sizeof(*pages)) *
- PAGE_SIZE) {
- size = ((((size / 2) - 1) |
- ~PAGE_MASK) + 1) & PAGE_MASK;
- CDEBUG(D_VFSTRACE, "DIO size now %zu\n",
- size);
- continue;
- }
+ result = ll_direct_rw_pages(env, io, count,
+ rw, inode, &pvec);
+ ll_free_user_pages(pages, pvec.ldp_count);
+ if (unlikely(result < 0))
GOTO(out, result);
- }
- iov_iter_advance(iter, result);
- tot_bytes += result;
- file_offset += result;
+ iov_iter_advance(iter, count);
+ tot_bytes += count;
+ file_offset += count;
}
-out:
- if (iov_iter_rw(iter) == READ)
- inode_unlock(inode);
- if (tot_bytes > 0) {
- struct vvp_io *vio = vvp_env_io(env);
+out:
+ aio->cda_bytes = tot_bytes;
+ cl_sync_io_note(env, &aio->cda_sync, result);
- /* no commit async for direct IO */
- vio->u.write.vui_written += tot_bytes;
- }
+ if (is_sync_kiocb(iocb)) {
+ ssize_t rc2;
- return tot_bytes ? : result;
-}
-#else /* !HAVE_DIRECTIO_ITER && !HAVE_IOV_ITER_RW */
+ rc2 = cl_sync_io_wait(env, &aio->cda_sync, 0);
+ if (result == 0 && rc2)
+ result = rc2;
-static inline int ll_get_user_pages(int rw, unsigned long user_addr,
- size_t size, struct page ***pages,
- int *max_pages)
-{
- int result = -ENOMEM;
+ if (result == 0) {
+ struct vvp_io *vio = vvp_env_io(env);
+ /* no commit async for direct IO */
+ vio->u.write.vui_written += tot_bytes;
+ result = tot_bytes;
+ }
+ OBD_FREE_PTR(aio);
- /* set an arbitrary limit to prevent arithmetic overflow */
- if (size > MAX_DIRECTIO_SIZE) {
- *pages = NULL;
- return -EFBIG;
+ } else {
+ result = -EIOCBQUEUED;
}
- *max_pages = (user_addr + size + PAGE_SIZE - 1) >>
- PAGE_SHIFT;
- *max_pages -= user_addr >> PAGE_SHIFT;
-
- OBD_ALLOC_LARGE(*pages, *max_pages * sizeof(**pages));
- if (*pages) {
- down_read(¤t->mm->mmap_sem);
- result = get_user_pages(current, current->mm, user_addr,
- *max_pages, (rw == READ), 0, *pages,
- NULL);
- up_read(¤t->mm->mmap_sem);
- if (unlikely(result <= 0))
- OBD_FREE_LARGE(*pages, *max_pages * sizeof(**pages));
- }
+ if (rw == READ)
+ inode_unlock(inode);
return result;
}
-static ssize_t
-ll_direct_IO(int rw, struct kiocb *iocb, const struct iovec *iov,
- loff_t file_offset, unsigned long nr_segs)
+#if defined(HAVE_DIO_ITER)
+static ssize_t ll_direct_IO(
+#ifndef HAVE_IOV_ITER_RW
+ int rw,
+#endif
+ struct kiocb *iocb, struct iov_iter *iter
+#ifndef HAVE_DIRECTIO_2ARGS
+ , loff_t file_offset
+#endif
+ )
{
- struct ll_cl_context *lcc;
- const struct lu_env *env;
- struct cl_io *io;
- struct file *file = iocb->ki_filp;
- struct inode *inode = file->f_mapping->host;
- ssize_t count = iov_length(iov, nr_segs);
- ssize_t tot_bytes = 0, result = 0;
- unsigned long seg = 0;
- size_t size = MAX_DIO_SIZE;
- ENTRY;
-
- /* FIXME: io smaller than PAGE_SIZE is broken on ia64 ??? */
- if ((file_offset & ~PAGE_MASK) || (count & ~PAGE_MASK))
- RETURN(-EINVAL);
+ int nrw;
- CDEBUG(D_VFSTRACE, "VFS Op:inode="DFID"(%p), size=%zd (max %lu), "
- "offset=%lld=%llx, pages %zd (max %lu)\n",
- PFID(ll_inode2fid(inode)), inode, count, MAX_DIO_SIZE,
- file_offset, file_offset, count >> PAGE_SHIFT,
- MAX_DIO_SIZE >> PAGE_SHIFT);
-
- /* Check that all user buffers are aligned as well */
- for (seg = 0; seg < nr_segs; seg++) {
- if (((unsigned long)iov[seg].iov_base & ~PAGE_MASK) ||
- (iov[seg].iov_len & ~PAGE_MASK))
- RETURN(-EINVAL);
- }
-
- lcc = ll_cl_find(file);
- if (lcc == NULL)
- RETURN(-EIO);
+#ifndef HAVE_IOV_ITER_RW
+ nrw = rw;
+#else
+ nrw = iov_iter_rw(iter);
+#endif
- env = lcc->lcc_env;
- LASSERT(!IS_ERR(env));
- io = lcc->lcc_io;
- LASSERT(io != NULL);
+ return ll_direct_IO_impl(iocb, iter, nrw);
+}
- for (seg = 0; seg < nr_segs; seg++) {
- size_t iov_left = iov[seg].iov_len;
- unsigned long user_addr = (unsigned long)iov[seg].iov_base;
-
- if (rw == READ) {
- if (file_offset >= i_size_read(inode))
- break;
- if (file_offset + iov_left > i_size_read(inode))
- iov_left = i_size_read(inode) - file_offset;
- }
-
- while (iov_left > 0) {
- struct page **pages;
- int page_count, max_pages = 0;
- size_t bytes;
-
- bytes = min(size, iov_left);
- page_count = ll_get_user_pages(rw, user_addr, bytes,
- &pages, &max_pages);
- if (likely(page_count > 0)) {
- if (unlikely(page_count < max_pages))
- bytes = page_count << PAGE_SHIFT;
- result = ll_direct_IO_seg(env, io, rw, inode,
- bytes, file_offset,
- pages, page_count);
- ll_free_user_pages(pages, max_pages, rw==READ);
- } else if (page_count == 0) {
- GOTO(out, result = -EFAULT);
- } else {
- result = page_count;
- }
- if (unlikely(result <= 0)) {
- /* If we can't allocate a large enough buffer
- * for the request, shrink it to a smaller
- * PAGE_SIZE multiple and try again.
- * We should always be able to kmalloc for a
- * page worth of page pointers = 4MB on i386. */
- if (result == -ENOMEM &&
- size > (PAGE_SIZE / sizeof(*pages)) *
- PAGE_SIZE) {
- size = ((((size / 2) - 1) |
- ~PAGE_MASK) + 1) &
- PAGE_MASK;
- CDEBUG(D_VFSTRACE, "DIO size now %zu\n",
- size);
- continue;
- }
-
- GOTO(out, result);
- }
-
- tot_bytes += result;
- file_offset += result;
- iov_left -= result;
- user_addr += result;
- }
- }
-out:
- if (tot_bytes > 0) {
- struct vvp_io *vio = vvp_env_io(env);
+#else /* !defined(HAVE_DIO_ITER) */
- /* no commit async for direct IO */
- vio->u.write.vui_written += tot_bytes;
- }
+static ssize_t
+ll_direct_IO(int rw, struct kiocb *iocb, const struct iovec *iov,
+ loff_t file_offset, unsigned long nr_segs)
+{
+ struct iov_iter iter;
- RETURN(tot_bytes ? tot_bytes : result);
+ iov_iter_init(&iter, iov, nr_segs, iov_length(iov, nr_segs), 0);
+ return ll_direct_IO_impl(iocb, &iter, rw);
}
-#endif /* HAVE_DIRECTIO_ITER || HAVE_IOV_ITER_RW */
+
+#endif /* !defined(HAVE_DIO_ITER) */
/**
* Prepare partially written-to page for a write.
+ * @pg is owned when passed in and disowned when it returns non-zero result to
+ * the caller.
*/
static int ll_prepare_partial_page(const struct lu_env *env, struct cl_io *io,
- struct cl_page *pg)
+ struct cl_page *pg, struct file *file)
{
struct cl_attr *attr = vvp_env_thread_attr(env);
struct cl_object *obj = io->ci_obj;
struct vvp_page *vpg = cl_object_page_slice(obj, pg);
loff_t offset = cl_offset(obj, vvp_index(vpg));
int result;
+ ENTRY;
cl_object_attr_lock(obj);
result = cl_object_attr_get(env, obj, attr);
cl_object_attr_unlock(obj);
- if (result == 0) {
- /*
- * If are writing to a new page, no need to read old data.
- * The extent locking will have updated the KMS, and for our
- * purposes here we can treat it like i_size.
- */
- if (attr->cat_kms <= offset) {
- char *kaddr = ll_kmap_atomic(vpg->vpg_page, KM_USER0);
+ if (result) {
+ cl_page_disown(env, io, pg);
+ GOTO(out, result);
+ }
- memset(kaddr, 0, cl_page_size(obj));
- ll_kunmap_atomic(kaddr, KM_USER0);
- } else if (vpg->vpg_defer_uptodate)
- vpg->vpg_ra_used = 1;
- else
- result = ll_page_sync_io(env, io, pg, CRT_READ);
+ /*
+ * If are writing to a new page, no need to read old data.
+ * The extent locking will have updated the KMS, and for our
+ * purposes here we can treat it like i_size.
+ */
+ if (attr->cat_kms <= offset) {
+ char *kaddr = ll_kmap_atomic(vpg->vpg_page, KM_USER0);
+
+ memset(kaddr, 0, cl_page_size(obj));
+ ll_kunmap_atomic(kaddr, KM_USER0);
+ GOTO(out, result = 0);
+ }
+
+ if (vpg->vpg_defer_uptodate) {
+ vpg->vpg_ra_used = 1;
+ GOTO(out, result = 0);
+ }
+
+ result = ll_io_read_page(env, io, pg, file);
+ if (result)
+ GOTO(out, result);
+
+ /* ll_io_read_page() disowns the page */
+ result = cl_page_own(env, io, pg);
+ if (!result) {
+ if (!PageUptodate(cl_page_vmpage(pg))) {
+ cl_page_disown(env, io, pg);
+ result = -EIO;
+ }
+ } else if (result == -ENOENT) {
+ /* page was truncated */
+ result = -EAGAIN;
}
+ EXIT;
+
+out:
return result;
}
+static int ll_tiny_write_begin(struct page *vmpage)
+{
+ /* Page must be present, up to date, dirty, and not in writeback. */
+ if (!vmpage || !PageUptodate(vmpage) || !PageDirty(vmpage) ||
+ PageWriteback(vmpage))
+ return -ENODATA;
+
+ return 0;
+}
+
static int ll_write_begin(struct file *file, struct address_space *mapping,
loff_t pos, unsigned len, unsigned flags,
struct page **pagep, void **fsdata)
{
- struct ll_cl_context *lcc;
+ struct ll_cl_context *lcc = NULL;
const struct lu_env *env = NULL;
- struct cl_io *io;
+ struct cl_io *io = NULL;
struct cl_page *page = NULL;
struct cl_object *clob = ll_i2info(mapping->host)->lli_clob;
int result = 0;
ENTRY;
- CDEBUG(D_PAGE, "Writing %lu of %d to %d bytes\n", index, from, len);
+ CDEBUG(D_VFSTRACE, "Writing %lu of %d to %d bytes\n", index, from, len);
lcc = ll_cl_find(file);
if (lcc == NULL) {
- io = NULL;
- GOTO(out, result = -EIO);
+ vmpage = grab_cache_page_nowait(mapping, index);
+ result = ll_tiny_write_begin(vmpage);
+ GOTO(out, result);
}
env = lcc->lcc_env;
io = lcc->lcc_io;
- if (file->f_flags & O_DIRECT && io->ci_designated_mirror > 0) {
+ if (file->f_flags & O_DIRECT) {
/* direct IO failed because it couldn't clean up cached pages,
* this causes a problem for mirror write because the cached
* page may belong to another mirror, which will result in
* problem submitting the I/O. */
- GOTO(out, result = -EBUSY);
- }
+ if (io->ci_designated_mirror > 0)
+ GOTO(out, result = -EBUSY);
+ /**
+ * Direct read can fall back to buffered read, but DIO is done
+ * with lockless i/o, and buffered requires LDLM locking, so
+ * in this case we must restart without lockless.
+ */
+ if (!io->ci_ignore_lockless) {
+ io->ci_ignore_lockless = 1;
+ io->ci_need_restart = 1;
+ GOTO(out, result = -ENOLCK);
+ }
+ }
+again:
/* To avoid deadlock, try to lock page first. */
vmpage = grab_cache_page_nowait(mapping, index);
/* TODO: can be optimized at OSC layer to check if it
* is a lockless IO. In that case, it's not necessary
* to read the data. */
- result = ll_prepare_partial_page(env, io, page);
- if (result == 0)
- SetPageUptodate(vmpage);
+ result = ll_prepare_partial_page(env, io, page, file);
+ if (result) {
+ /* vmpage should have been unlocked */
+ put_page(vmpage);
+ vmpage = NULL;
+
+ if (result == -EAGAIN)
+ goto again;
+ GOTO(out, result);
+ }
}
}
- if (result < 0)
- cl_page_unassume(env, io, page);
EXIT;
out:
if (result < 0) {
unlock_page(vmpage);
put_page(vmpage);
}
+ /* On tiny_write failure, page and io are always null. */
if (!IS_ERR_OR_NULL(page)) {
lu_ref_del(&page->cp_reference, "cl_io", io);
cl_page_put(env, page);
RETURN(result);
}
+static int ll_tiny_write_end(struct file *file, struct address_space *mapping,
+ loff_t pos, unsigned int len, unsigned int copied,
+ struct page *vmpage)
+{
+ struct cl_page *clpage = (struct cl_page *) vmpage->private;
+ loff_t kms = pos+copied;
+ loff_t to = kms & (PAGE_SIZE-1) ? kms & (PAGE_SIZE-1) : PAGE_SIZE;
+ __u16 refcheck;
+ struct lu_env *env = cl_env_get(&refcheck);
+ int rc = 0;
+
+ ENTRY;
+
+ if (IS_ERR(env)) {
+ rc = PTR_ERR(env);
+ goto out;
+ }
+
+ /* This page is dirty in cache, so it should have a cl_page pointer
+ * set in vmpage->private.
+ */
+ LASSERT(clpage != NULL);
+
+ if (copied == 0)
+ goto out_env;
+
+ /* Update the underlying size information in the OSC/LOV objects this
+ * page is part of.
+ */
+ cl_page_touch(env, clpage, to);
+
+out_env:
+ cl_env_put(env, &refcheck);
+
+out:
+ /* Must return page unlocked. */
+ unlock_page(vmpage);
+
+ RETURN(rc);
+}
+
static int ll_write_end(struct file *file, struct address_space *mapping,
loff_t pos, unsigned len, unsigned copied,
struct page *vmpage, void *fsdata)
put_page(vmpage);
+ CDEBUG(D_VFSTRACE, "pos %llu, len %u, copied %u\n", pos, len, copied);
+
+ if (lcc == NULL) {
+ result = ll_tiny_write_end(file, mapping, pos, len, copied,
+ vmpage);
+ GOTO(out, result);
+ }
+
LASSERT(lcc != NULL);
env = lcc->lcc_env;
page = lcc->lcc_page;
if (plist->pl_nr >= PTLRPC_MAX_BRW_PAGES)
unplug = true;
- CL_PAGE_DEBUG(D_PAGE, env, page,
+ CL_PAGE_DEBUG(D_VFSTRACE, env, page,
"queued page: %d.\n", plist->pl_nr);
} else {
cl_page_disown(env, io, page);
/* page list is not contiguous now, commit it now */
unplug = true;
}
- if (unplug ||
- file->f_flags & O_SYNC || IS_SYNC(file_inode(file)))
+ if (unplug || io->u.ci_wr.wr_sync)
result = vvp_io_write_commit(env, io);
if (result < 0)
io->ci_result = result;
+
+
+out:
RETURN(result >= 0 ? copied : result);
}