exofs: Cleaup read path in regard with read_for_write

Last BUG fix added a flag to the the page_collect structure
to communicate with readpage_strip. This calls for a clean up
removing that flag's reincarnations in the read functions
parameters.

Signed-off-by: Boaz Harrosh <Boaz Harrosh bharrosh@panasas.com>

diff --git a/fs/exofs/inode.c b/fs/exofs/inode.c
index 3eadd97..24ab327 100644 (file)
--- a/fs/exofs/inode.c
+++ b/fs/exofs/inode.c
@@ -185,7 +185,7 @@ static void update_write_page(struct page *page, int ret)
 /* Called at the end of reads, to optionally unlock pages and update their
  * status.
  */
-static int __readpages_done(struct page_collect *pcol, bool do_unlock)
+static int __readpages_done(struct page_collect *pcol)
 {
        int i;
        u64 resid;
@@ -221,7 +221,7 @@ static int __readpages_done(struct page_collect *pcol, bool do_unlock)
                          page_stat ? "bad_bytes" : "good_bytes");
 
                ret = update_read_page(page, page_stat);
-               if (do_unlock)
+               if (!pcol->read_4_write)
                        unlock_page(page);
                length += PAGE_SIZE;
        }
@@ -236,7 +236,7 @@ static void readpages_done(struct exofs_io_state *ios, void *p)
 {
        struct page_collect *pcol = p;
 
-       __readpages_done(pcol, true);
+       __readpages_done(pcol);
        atomic_dec(&pcol->sbi->s_curr_pending);
        kfree(pcol);
 }
@@ -257,7 +257,7 @@ static void _unlock_pcol_pages(struct page_collect *pcol, int ret, int rw)
        }
 }
 
-static int read_exec(struct page_collect *pcol, bool is_sync)
+static int read_exec(struct page_collect *pcol)
 {
        struct exofs_i_info *oi = exofs_i(pcol->inode);
        struct exofs_io_state *ios = pcol->ios;
@@ -267,17 +267,14 @@ static int read_exec(struct page_collect *pcol, bool is_sync)
        if (!pcol->pages)
                return 0;
 
-       /* see comment in _readpage() about sync reads */
-       WARN_ON(is_sync && (pcol->nr_pages != 1));
-
        ios->pages = pcol->pages;
        ios->nr_pages = pcol->nr_pages;
        ios->length = pcol->length;
        ios->offset = pcol->pg_first << PAGE_CACHE_SHIFT;
 
-       if (is_sync) {
+       if (pcol->read_4_write) {
                exofs_oi_read(oi, pcol->ios);
-               return __readpages_done(pcol, false);
+               return __readpages_done(pcol);
        }
 
        pcol_copy = kmalloc(sizeof(*pcol_copy), GFP_KERNEL);
@@ -303,7 +300,7 @@ static int read_exec(struct page_collect *pcol, bool is_sync)
        return 0;
 
 err:
-       if (!is_sync)
+       if (!pcol->read_4_write)
                _unlock_pcol_pages(pcol, ret, READ);
 
        pcol_free(pcol);
@@ -356,7 +353,7 @@ static int readpage_strip(void *data, struct page *page)
                EXOFS_DBGMSG("readpage_strip(0x%lx, 0x%lx) empty page,"
                             " splitting\n", inode->i_ino, page->index);
 
-               return read_exec(pcol, false);
+               return read_exec(pcol);
        }
 
 try_again:
@@ -366,7 +363,7 @@ try_again:
        } else if (unlikely((pcol->pg_first + pcol->nr_pages) !=
                   page->index)) {
                /* Discontinuity detected, split the request */
-               ret = read_exec(pcol, false);
+               ret = read_exec(pcol);
                if (unlikely(ret))
                        goto fail;
                goto try_again;
@@ -391,7 +388,7 @@ try_again:
                          page, len, pcol->nr_pages, pcol->length);
 
                /* split the request, and start again with current page */
-               ret = read_exec(pcol, false);
+               ret = read_exec(pcol);
                if (unlikely(ret))
                        goto fail;
 
@@ -420,27 +417,24 @@ static int exofs_readpages(struct file *file, struct address_space *mapping,
                return ret;
        }
 
-       return read_exec(&pcol, false);
+       return read_exec(&pcol);
 }
 
-static int _readpage(struct page *page, bool is_sync)
+static int _readpage(struct page *page, bool read_4_write)
 {
        struct page_collect pcol;
        int ret;
 
        _pcol_init(&pcol, 1, page->mapping->host);
 
-       /* readpage_strip might call read_exec(,is_sync==false) at several
-        * places but not if we have a single page.
-        */
-       pcol.read_4_write = is_sync;
+       pcol.read_4_write = read_4_write;
        ret = readpage_strip(&pcol, page);
        if (ret) {
                EXOFS_ERR("_readpage => %d\n", ret);
                return ret;
        }
 
-       return read_exec(&pcol, is_sync);
+       return read_exec(&pcol);
 }
 
 /*