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@@ -133,15 +133,12 @@ out:
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}
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/*
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- * do_page_cache_readahead actually reads a chunk of disk. It allocates all
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+ * __do_page_cache_readahead() actually reads a chunk of disk. It allocates all
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* the pages first, then submits them all for I/O. This avoids the very bad
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* behaviour which would occur if page allocations are causing VM writeback.
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* We really don't want to intermingle reads and writes like that.
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*
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* Returns the number of pages requested, or the maximum amount of I/O allowed.
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- *
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- * do_page_cache_readahead() returns -1 if it encountered request queue
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- * congestion.
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*/
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static int
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__do_page_cache_readahead(struct address_space *mapping, struct file *filp,
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@@ -231,22 +228,6 @@ int force_page_cache_readahead(struct address_space *mapping, struct file *filp,
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return ret;
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}
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-/*
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- * This version skips the IO if the queue is read-congested, and will tell the
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- * block layer to abandon the readahead if request allocation would block.
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- *
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- * force_page_cache_readahead() will ignore queue congestion and will block on
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- * request queues.
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- */
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-int do_page_cache_readahead(struct address_space *mapping, struct file *filp,
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- pgoff_t offset, unsigned long nr_to_read)
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-{
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- if (bdi_read_congested(mapping->backing_dev_info))
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- return -1;
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-
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- return __do_page_cache_readahead(mapping, filp, offset, nr_to_read, 0);
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-}
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-
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/*
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* Given a desired number of PAGE_CACHE_SIZE readahead pages, return a
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* sensible upper limit.
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@@ -260,7 +241,7 @@ unsigned long max_sane_readahead(unsigned long nr)
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/*
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* Submit IO for the read-ahead request in file_ra_state.
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*/
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-static unsigned long ra_submit(struct file_ra_state *ra,
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+unsigned long ra_submit(struct file_ra_state *ra,
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struct address_space *mapping, struct file *filp)
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{
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int actual;
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