[Patch v3 01/16] CIFS: Add support for direct pages in rdata
From: Long Li <hidden>
Date: 2018-09-08 02:15:23
Also in:
linux-cifs, lkml
Subsystem:
filesystems (vfs and infrastructure), the rest · Maintainers:
Alexander Viro, Christian Brauner, Linus Torvalds
From: Long Li <longli@microsoft.com> Add a function to allocate rdata without allocating pages for data transfer. This gives the caller an option to pass a number of pages that point to the data buffer. rdata is reponsible for free those pages after it's done. Signed-off-by: Long Li <longli@microsoft.com> --- fs/cifs/cifsglob.h | 3 +-- fs/cifs/file.c | 23 ++++++++++++++++++++--- 2 files changed, 21 insertions(+), 5 deletions(-)
diff --git a/fs/cifs/cifsglob.h b/fs/cifs/cifsglob.h
index 80a34ce..166e140 100644
--- a/fs/cifs/cifsglob.h
+++ b/fs/cifs/cifsglob.h@@ -1173,14 +1173,13 @@ struct cifs_readdata { struct kvec iov[2]; #ifdef CONFIG_CIFS_SMB_DIRECT struct smbd_mr *mr; - struct page **direct_pages; #endif unsigned int pagesz; unsigned int page_offset; unsigned int tailsz; unsigned int credits; unsigned int nr_pages; - struct page *pages[]; + struct page **pages; }; struct cifs_writedata;
diff --git a/fs/cifs/file.c b/fs/cifs/file.c
index 23fd430..1c98293 100644
--- a/fs/cifs/file.c
+++ b/fs/cifs/file.c@@ -2880,13 +2880,13 @@ cifs_strict_writev(struct kiocb *iocb, struct iov_iter *from) } static struct cifs_readdata * -cifs_readdata_alloc(unsigned int nr_pages, work_func_t complete) +cifs_readdata_direct_alloc(struct page **pages, work_func_t complete) { struct cifs_readdata *rdata; - rdata = kzalloc(sizeof(*rdata) + (sizeof(struct page *) * nr_pages), - GFP_KERNEL); + rdata = kzalloc(sizeof(*rdata), GFP_KERNEL); if (rdata != NULL) { + rdata->pages = pages; kref_init(&rdata->refcount); INIT_LIST_HEAD(&rdata->list); init_completion(&rdata->done);
@@ -2896,6 +2896,22 @@ cifs_readdata_alloc(unsigned int nr_pages, work_func_t complete) return rdata; } +static struct cifs_readdata * +cifs_readdata_alloc(unsigned int nr_pages, work_func_t complete) +{ + struct page **pages = + kzalloc(sizeof(struct page *) * nr_pages, GFP_KERNEL); + struct cifs_readdata *ret = NULL; + + if (pages) { + ret = cifs_readdata_direct_alloc(pages, complete); + if (!ret) + kfree(pages); + } + + return ret; +} + void cifs_readdata_release(struct kref *refcount) {
@@ -2910,6 +2926,7 @@ cifs_readdata_release(struct kref *refcount) if (rdata->cfile) cifsFileInfo_put(rdata->cfile); + kvfree(rdata->pages); kfree(rdata); }
--
2.7.4