kclient: write_begin and write_end

diff --git a/src/TODO b/src/TODO
index 5f29b371e3ed5c95c23ea12bb4e43e54daa6f55f..2d371b329b86f43b6dfc146d23966d212d3e99c1 100644 (file)
--- a/src/TODO
+++ b/src/TODO
@@ -16,8 +16,6 @@ userspace client
 - reference count lease validations on path lookup?
 
 kernel client
-- use list_for_each_safe for caps removal?
-  - revisit cap removal locking, make sure it's okay....
 - trim expired leases so we don't indefinitely hold dcache refs...
 - carry wrbuffer/rdcache caps until data is flushed
   - this should make the utimes bit kick in

diff --git a/src/kernel/addr.c b/src/kernel/addr.c
index 1cc7a2ecef25fcaef141071cfa1dd2f98598eac1..9809b968eeb04cb8a5b2fdb3ced8650719690c2a 100644 (file)
--- a/src/kernel/addr.c
+++ b/src/kernel/addr.c
@@ -62,30 +62,30 @@ out_unlock:
  */
 static int ceph_writepage(struct page *page, struct writeback_control *wbc)
 {
-       struct inode *inode = page->mapping->host;
-       struct ceph_inode_info *ci;
-       struct ceph_osd_client *osdc;
-       int err = 0;
-
-       if (!page->mapping || !page->mapping->host)
-              return -EFAULT;
-
-       ci = ceph_inode(inode);
-       osdc = &ceph_inode_to_client(inode)->osdc;
-
-       get_page(page);
-       set_page_writeback(page);
-       SetPageUptodate(page);
-
-       dout(10, "ceph_writepage inode %p page %p index %lu\n",
-           inode, page, page->index);
-
+       struct inode *inode = page->mapping->host;
+       struct ceph_inode_info *ci;
+       struct ceph_osd_client *osdc;
+       int err = 0;
+       
+       if (!page->mapping || !page->mapping->host)
+               return -EFAULT;
+       
+       ci = ceph_inode(inode);
+       osdc = &ceph_inode_to_client(inode)->osdc;
+       
+       get_page(page);
+       set_page_writeback(page);
+       SetPageUptodate(page);
+       
+       dout(10, "ceph_writepage inode %p page %p index %lu\n",
+            inode, page, page->index);
+       
        /* write a page at the index of page->index, by size of PAGE_SIZE */
        err = ceph_osdc_writepage(osdc, ceph_ino(inode), &ci->i_layout,
-                               page->index << PAGE_SHIFT, PAGE_SIZE, page);
+                                 page->index << PAGE_SHIFT, PAGE_SIZE, page);
        if (err)
                goto out_unlock;
-
+       
        /* update written data size in ceph_inode_info */
        spin_lock(&inode->i_lock);
        if (inode->i_size <= PAGE_SIZE) {
@@ -94,12 +94,12 @@ static int ceph_writepage(struct page *page, struct writeback_control *wbc)
                dout(10, "extending file size to %d\n", (int)inode->i_size);
        }
        spin_unlock(&inode->i_lock);
-
+       
 out_unlock:
        end_page_writeback(page);
        put_page(page);
-
-       return err;
+       
+       return err;
 }
 
 /*
@@ -125,6 +125,7 @@ static int ceph_writepages(struct address_space *mapping, struct writeback_contr
        return generic_writepages(mapping, wbc);
 }
 
+
 /*
  * ceph_prepare_write:
  *  allocate and initialize buffer heads for each page
@@ -233,6 +234,7 @@ static int ceph_commit_write(struct file *filp, struct page *page,
                /* set the page as up-to-date and mark it as dirty */
                SetPageUptodate(page);
                set_page_dirty(page);
+               ci->i_nr_dirty_pages++;
        }
 
 /*out_unlock:*/
@@ -240,11 +242,133 @@ static int ceph_commit_write(struct file *filp, struct page *page,
 }
 
 
+/*
+ * newer write interface
+ */
+static int ceph_write_begin(struct file *file, struct address_space *mapping,
+                           loff_t pos, unsigned len, unsigned flags,
+                           struct page **pagep, void **fsdata)
+{
+       struct inode *inode = file->f_dentry->d_inode;
+       struct ceph_inode_info *ci;
+       struct ceph_osd_client *osdc = &ceph_inode_to_client(inode)->osdc;
+       struct page *page;
+       pgoff_t index = pos >> PAGE_CACHE_SHIFT;
+       loff_t page_off = pos & PAGE_MASK;
+       int pos_in_page = pos & ~PAGE_MASK;
+       loff_t i_size;
+       int r;
+
+       /* get a page*/
+       page = __grab_cache_page(mapping, index);
+       if (!page) 
+               return -ENOMEM;
+       *pagep = page;
+
+       dout(10, "write_begin file %p inode %p page %p %d~%d\n", file,
+            inode, page, (int)pos, (int)len);
+
+       if (PageUptodate(page))
+               return 0;
+
+       /* full page? */
+       if (pos_in_page == 0 && len == PAGE_SIZE) {  
+               SetPageUptodate(page);
+               return 0;
+       }
+       
+       /* past end of file? */
+       i_size = i_size_read(inode);
+       if (page_off >= i_size || 
+           (pos_in_page == 0 && (pos+len) >= i_size)) {
+               simple_prepare_write(file, page, pos_in_page, pos_in_page+len);
+               SetPageUptodate(page);
+               return 0;
+       }
+       
+       /* we need to read it. */
+       /* or, do sub-page granularity dirty accounting? */
+       /* try to read the full page */
+       ci = ceph_inode(inode);
+       r = ceph_osdc_readpage(osdc, ceph_ino(inode), &ci->i_layout,
+                              page_off, PAGE_SIZE, page);
+       if (r < 0)
+               return r;
+       if (r < pos_in_page) {
+               /* we didn't read up to our write start pos, zero the gap */
+               void *kaddr = kmap_atomic(page, KM_USER0);
+               memset(kaddr+r, 0, pos_in_page-r);
+               flush_dcache_page(page);
+               kunmap_atomic(kaddr, KM_USER0);
+       }
+       return 0;
+}
+
+static int ceph_write_end(struct file *file, struct address_space *mapping,
+                         loff_t pos, unsigned len, unsigned copied,
+                         struct page *page, void *fsdata)
+{
+       struct inode *inode = file->f_dentry->d_inode;
+       unsigned offset = pos & (PAGE_CACHE_SIZE - 1);
+
+       dout(10, "write_end file %p inode %p page %p %d~%d (%d)\n", file,
+            inode, page, (int)pos, (int)copied, (int)len);
+
+       /* did file size increase? */
+       spin_lock(&inode->i_lock);
+       if (pos+copied > inode->i_size)
+               i_size_write(inode, pos + copied);
+       spin_unlock(&inode->i_lock);
+
+       SetPageUptodate(page);
+       set_page_dirty(page);
+       unlock_page(page);
+
+       return copied;
+}
+
+
+
+/* generic_perform_write
+ * page accounting
+ */
+
+static int ceph_set_page_dirty(struct page *page)
+{
+       struct ceph_inode_info *ci = ceph_inode(page->mapping->host);
+       spin_lock(&ci->vfs_inode.i_lock);
+       dout(10, "set_page_dirty %p : %d -> %d \n", page,
+            ci->i_nr_dirty_pages, ci->i_nr_dirty_pages + 1);
+       ci->i_nr_dirty_pages++;
+       spin_lock(&ci->vfs_inode.i_lock);
+       return 0;
+}
+
+static int ceph_releasepage(struct page *page, gfp_t gfpmask)
+{
+       struct ceph_inode_info *ci = ceph_inode(page->mapping->host);
+       int last = 0;
+       spin_lock(&ci->vfs_inode.i_lock);
+       dout(10, "releasepage %p gfpmask %d : %d -> %d \n", page, gfpmask,
+            ci->i_nr_pages, ci->i_nr_pages - 1);
+       if (--ci->i_nr_pages == 0)
+               last++;
+       spin_lock(&ci->vfs_inode.i_lock);
+       if (last)
+               ceph_check_caps_wanted(ci, gfpmask);
+       return 0;
+}
+
+
 const struct address_space_operations ceph_aops = {
        .readpage = ceph_readpage,
        .readpages = ceph_readpages,
-       .prepare_write = ceph_prepare_write,
-       .commit_write = ceph_commit_write,
+       .write_begin = ceph_write_begin,
+       .write_end = ceph_write_end,
+       //.prepare_write = ceph_prepare_write,
+       //.commit_write = ceph_commit_write,
        .writepage = ceph_writepage,
 //     .writepages = ceph_writepages,
+//     .set_page_dirty = ceph_set_page_dirty,
+       .releasepage = ceph_releasepage,
 };

diff --git a/src/kernel/inode.c b/src/kernel/inode.c
index abb24b30b468c455c88d8be381eede60f4f12dd2..52d4fa023c59cbd49a703eb72a1a3268d109506a 100644 (file)
--- a/src/kernel/inode.c
+++ b/src/kernel/inode.c
@@ -689,7 +689,7 @@ void ceph_remove_cap(struct ceph_inode_cap *cap)
  * examine currently wanted versus held caps, and release caps to mds
  * as appropriate.
  */
-void ceph_check_caps_wanted(struct ceph_inode_info *ci)
+void ceph_check_caps_wanted(struct ceph_inode_info *ci, gfp_t gfpmask)
 {
        struct ceph_client *client = ceph_inode_to_client(&ci->vfs_inode);
        struct ceph_mds_client *mdsc = &client->mdsc;
@@ -711,6 +711,13 @@ retry:
                if ((cap->caps & ~wanted) == 0)
                        continue;     /* nothing extra, all good */
 
+               if (gfpmask != GFP_KERNEL) {
+                       /* put on examine list */
+                       dout(10, "** dropping caps, but bad gfpmask, "
+                            "IMPLEMENT ME *************\n");
+                       goto out;
+               }
+
                cap->caps &= wanted;  /* drop bits we don't want */
 
                keep = cap->caps;
@@ -734,6 +741,7 @@ retry:
        }
 
        /* okay */
+out:
        spin_unlock(&ci->vfs_inode.i_lock);
 }
 
@@ -758,7 +766,7 @@ void ceph_put_mode(struct ceph_inode_info *ci, int mode)
        spin_unlock(&ci->vfs_inode.i_lock);
 
        if (last)
-               ceph_check_caps_wanted(ci);
+               ceph_check_caps_wanted(ci, GFP_KERNEL);
 }
 
 
@@ -944,7 +952,7 @@ void ceph_put_cap_refs(struct ceph_inode_info *ci, int had)
        spin_unlock(&ci->vfs_inode.i_lock);
 
        if (last) 
-               ceph_check_caps_wanted(ci);
+               ceph_check_caps_wanted(ci, GFP_KERNEL);
 }
 
 

diff --git a/src/kernel/super.c b/src/kernel/super.c
index a32ab1b244c8acd6c0cc9c54f2faa8a646a55b9a..297498164dca539397ac24301bb61703b6bcbf6d 100644 (file)
--- a/src/kernel/super.c
+++ b/src/kernel/super.c
@@ -132,6 +132,7 @@ static struct inode *ceph_alloc_inode(struct super_block *sb)
 
        ci->i_rd_ref = ci->i_rdcache_ref = 0;
        ci->i_wr_ref = ci->i_wrbuffer_ref = 0;
+       ci->i_nr_pages = ci->i_nr_dirty_pages = 0;
 
        ci->i_hashval = 0;
 

diff --git a/src/kernel/super.h b/src/kernel/super.h
index ef7f13123a87c6554a67f9922d6c44b8c12d93f1..dc6043c026e311b1eb2ee7e65d30e1d5ef173fa1 100644 (file)
--- a/src/kernel/super.h
+++ b/src/kernel/super.h
@@ -166,6 +166,8 @@ struct ceph_inode_info {
 
        int i_rd_ref, i_rdcache_ref, i_wr_ref, i_wrbuffer_ref;
 
+       int i_nr_pages, i_nr_dirty_pages; // hrm!
+
        unsigned long i_hashval;
 
        struct inode vfs_inode; /* at end */
@@ -361,7 +363,7 @@ extern int ceph_handle_cap_trunc(struct inode *inode,
                                 struct ceph_mds_session *session);
 extern int ceph_get_cap_refs(struct ceph_inode_info *ci, int need, int want, int *got);
 extern void ceph_put_cap_refs(struct ceph_inode_info *ci, int had);
-extern void ceph_check_caps_wanted(struct ceph_inode_info *ci);
+extern void ceph_check_caps_wanted(struct ceph_inode_info *ci, gfp_t gfpmask);
 extern void ceph_get_mode(struct ceph_inode_info *ci, int mode);
 extern void ceph_put_mode(struct ceph_inode_info *ci, int mode);