[CIFS] Change semaphore to mutex for cifs lock_sem
[powerpc.git] / fs / nfs / write.c
index dea1737..2867e6b 100644 (file)
@@ -12,6 +12,7 @@
 #include <linux/pagemap.h>
 #include <linux/file.h>
 #include <linux/writeback.h>
+#include <linux/swap.h>
 
 #include <linux/sunrpc/clnt.h>
 #include <linux/nfs_fs.h>
@@ -38,7 +39,6 @@ static struct nfs_page * nfs_update_request(struct nfs_open_context*,
                                            struct page *,
                                            unsigned int, unsigned int);
 static void nfs_mark_request_dirty(struct nfs_page *req);
-static int nfs_wait_on_write_congestion(struct address_space *, int);
 static long nfs_flush_mapping(struct address_space *mapping, struct writeback_control *wbc, int how);
 static const struct rpc_call_ops nfs_write_partial_ops;
 static const struct rpc_call_ops nfs_write_full_ops;
@@ -48,8 +48,6 @@ static struct kmem_cache *nfs_wdata_cachep;
 static mempool_t *nfs_wdata_mempool;
 static mempool_t *nfs_commit_mempool;
 
-static DECLARE_WAIT_QUEUE_HEAD(nfs_write_congestion);
-
 struct nfs_write_data *nfs_commit_alloc(void)
 {
        struct nfs_write_data *p = mempool_alloc(nfs_commit_mempool, GFP_NOFS);
@@ -153,6 +151,13 @@ static void nfs_grow_file(struct page *page, unsigned int offset, unsigned int c
        i_size_write(inode, end);
 }
 
+/* A writeback failed: mark the page as bad, and invalidate the page cache */
+static void nfs_set_pageerror(struct page *page)
+{
+       SetPageError(page);
+       nfs_zap_mapping(page->mapping->host, page->mapping);
+}
+
 /* We can set the PG_uptodate flag if we see that a write request
  * covers the full page.
  */
@@ -203,6 +208,40 @@ static int wb_priority(struct writeback_control *wbc)
        return 0;
 }
 
+/*
+ * NFS congestion control
+ */
+
+int nfs_congestion_kb;
+
+#define NFS_CONGESTION_ON_THRESH       (nfs_congestion_kb >> (PAGE_SHIFT-10))
+#define NFS_CONGESTION_OFF_THRESH      \
+       (NFS_CONGESTION_ON_THRESH - (NFS_CONGESTION_ON_THRESH >> 2))
+
+static void nfs_set_page_writeback(struct page *page)
+{
+       if (!test_set_page_writeback(page)) {
+               struct inode *inode = page->mapping->host;
+               struct nfs_server *nfss = NFS_SERVER(inode);
+
+               if (atomic_inc_return(&nfss->writeback) >
+                               NFS_CONGESTION_ON_THRESH)
+                       set_bdi_congested(&nfss->backing_dev_info, WRITE);
+       }
+}
+
+static void nfs_end_page_writeback(struct page *page)
+{
+       struct inode *inode = page->mapping->host;
+       struct nfs_server *nfss = NFS_SERVER(inode);
+
+       end_page_writeback(page);
+       if (atomic_dec_return(&nfss->writeback) < NFS_CONGESTION_OFF_THRESH) {
+               clear_bdi_congested(&nfss->backing_dev_info, WRITE);
+               congestion_end(WRITE);
+       }
+}
+
 /*
  * Find an associated nfs write request, and prepare to flush it out
  * Returns 1 if there was no write request, or if the request was
@@ -240,7 +279,7 @@ static int nfs_page_mark_flush(struct page *page)
        spin_unlock(req_lock);
        if (test_and_set_bit(PG_FLUSHING, &req->wb_flags) == 0) {
                nfs_mark_request_dirty(req);
-               set_page_writeback(page);
+               nfs_set_page_writeback(page);
        }
        ret = test_bit(PG_NEED_FLUSH, &req->wb_flags);
        nfs_unlock_request(req);
@@ -295,13 +334,8 @@ int nfs_writepage(struct page *page, struct writeback_control *wbc)
        return err; 
 }
 
-/*
- * Note: causes nfs_update_request() to block on the assumption
- *      that the writeback is generated due to memory pressure.
- */
 int nfs_writepages(struct address_space *mapping, struct writeback_control *wbc)
 {
-       struct backing_dev_info *bdi = mapping->backing_dev_info;
        struct inode *inode = mapping->host;
        int err;
 
@@ -310,20 +344,12 @@ int nfs_writepages(struct address_space *mapping, struct writeback_control *wbc)
        err = generic_writepages(mapping, wbc);
        if (err)
                return err;
-       while (test_and_set_bit(BDI_write_congested, &bdi->state) != 0) {
-               if (wbc->nonblocking)
-                       return 0;
-               nfs_wait_on_write_congestion(mapping, 0);
-       }
        err = nfs_flush_mapping(mapping, wbc, wb_priority(wbc));
        if (err < 0)
                goto out;
        nfs_add_stats(inode, NFSIOS_WRITEPAGES, err);
        err = 0;
 out:
-       clear_bit(BDI_write_congested, &bdi->state);
-       wake_up_all(&nfs_write_congestion);
-       congestion_end(WRITE);
        return err;
 }
 
@@ -353,7 +379,7 @@ static int nfs_inode_add_request(struct inode *inode, struct nfs_page *req)
 }
 
 /*
- * Insert a write request into an inode
+ * Remove a write request from an inode
  */
 static void nfs_inode_remove_request(struct nfs_page *req)
 {
@@ -524,10 +550,10 @@ static inline int nfs_scan_commit(struct inode *inode, struct list_head *dst, un
 }
 #endif
 
-static int nfs_wait_on_write_congestion(struct address_space *mapping, int intr)
+static int nfs_wait_on_write_congestion(struct address_space *mapping)
 {
+       struct inode *inode = mapping->host;
        struct backing_dev_info *bdi = mapping->backing_dev_info;
-       DEFINE_WAIT(wait);
        int ret = 0;
 
        might_sleep();
@@ -535,31 +561,23 @@ static int nfs_wait_on_write_congestion(struct address_space *mapping, int intr)
        if (!bdi_write_congested(bdi))
                return 0;
 
-       nfs_inc_stats(mapping->host, NFSIOS_CONGESTIONWAIT);
+       nfs_inc_stats(inode, NFSIOS_CONGESTIONWAIT);
 
-       if (intr) {
-               struct rpc_clnt *clnt = NFS_CLIENT(mapping->host);
+       do {
+               struct rpc_clnt *clnt = NFS_CLIENT(inode);
                sigset_t oldset;
 
                rpc_clnt_sigmask(clnt, &oldset);
-               prepare_to_wait(&nfs_write_congestion, &wait, TASK_INTERRUPTIBLE);
-               if (bdi_write_congested(bdi)) {
-                       if (signalled())
-                               ret = -ERESTARTSYS;
-                       else
-                               schedule();
-               }
+               ret = congestion_wait_interruptible(WRITE, HZ/10);
                rpc_clnt_sigunmask(clnt, &oldset);
-       } else {
-               prepare_to_wait(&nfs_write_congestion, &wait, TASK_UNINTERRUPTIBLE);
-               if (bdi_write_congested(bdi))
-                       schedule();
-       }
-       finish_wait(&nfs_write_congestion, &wait);
+               if (ret == -ERESTARTSYS)
+                       break;
+               ret = 0;
+       } while (bdi_write_congested(bdi));
+
        return ret;
 }
 
-
 /*
  * Try to update any existing write request, or create one if there is none.
  * In order to match, the request's credentials must match those of
@@ -570,14 +588,15 @@ static int nfs_wait_on_write_congestion(struct address_space *mapping, int intr)
 static struct nfs_page * nfs_update_request(struct nfs_open_context* ctx,
                struct page *page, unsigned int offset, unsigned int bytes)
 {
-       struct inode *inode = page->mapping->host;
+       struct address_space *mapping = page->mapping;
+       struct inode *inode = mapping->host;
        struct nfs_inode *nfsi = NFS_I(inode);
        struct nfs_page         *req, *new = NULL;
        unsigned long           rqend, end;
 
        end = offset + bytes;
 
-       if (nfs_wait_on_write_congestion(page->mapping, NFS_SERVER(inode)->flags & NFS_MOUNT_INTR))
+       if (nfs_wait_on_write_congestion(mapping))
                return ERR_PTR(-ERESTARTSYS);
        for (;;) {
                /* Loop over all inode entries and see if we find
@@ -714,13 +733,13 @@ int nfs_updatepage(struct file *file, struct page *page,
         dprintk("NFS:      nfs_updatepage returns %d (isize %Ld)\n",
                        status, (long long)i_size_read(inode));
        if (status < 0)
-               ClearPageUptodate(page);
+               nfs_set_pageerror(page);
        return status;
 }
 
 static void nfs_writepage_release(struct nfs_page *req)
 {
-       end_page_writeback(req->wb_page);
+       nfs_end_page_writeback(req->wb_page);
 
 #if defined(CONFIG_NFS_V3) || defined(CONFIG_NFS_V4)
        if (!PageError(req->wb_page)) {
@@ -976,8 +995,7 @@ static void nfs_writeback_done_partial(struct rpc_task *task, void *calldata)
                return;
 
        if (task->tk_status < 0) {
-               ClearPageUptodate(page);
-               SetPageError(page);
+               nfs_set_pageerror(page);
                req->wb_context->error = task->tk_status;
                dprintk(", error = %d\n", task->tk_status);
        } else {
@@ -1034,15 +1052,14 @@ static void nfs_writeback_done_full(struct rpc_task *task, void *calldata)
                        (long long)req_offset(req));
 
                if (task->tk_status < 0) {
-                       ClearPageUptodate(page);
-                       SetPageError(page);
+                       nfs_set_pageerror(page);
                        req->wb_context->error = task->tk_status;
-                       end_page_writeback(page);
+                       nfs_end_page_writeback(page);
                        nfs_inode_remove_request(req);
                        dprintk(", error = %d\n", task->tk_status);
                        goto next;
                }
-               end_page_writeback(page);
+               nfs_end_page_writeback(page);
 
 #if defined(CONFIG_NFS_V3) || defined(CONFIG_NFS_V4)
                if (data->args.stable != NFS_UNSTABLE || data->verf.committed == NFS_FILE_SYNC) {
@@ -1509,6 +1526,26 @@ int __init nfs_init_writepagecache(void)
        if (nfs_commit_mempool == NULL)
                return -ENOMEM;
 
+       /*
+        * NFS congestion size, scale with available memory.
+        *
+        *  64MB:    8192k
+        * 128MB:   11585k
+        * 256MB:   16384k
+        * 512MB:   23170k
+        *   1GB:   32768k
+        *   2GB:   46340k
+        *   4GB:   65536k
+        *   8GB:   92681k
+        *  16GB:  131072k
+        *
+        * This allows larger machines to have larger/more transfers.
+        * Limit the default to 256M
+        */
+       nfs_congestion_kb = (16*int_sqrt(totalram_pages)) << (PAGE_SHIFT-10);
+       if (nfs_congestion_kb > 256*1024)
+               nfs_congestion_kb = 256*1024;
+
        return 0;
 }