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How can I read more than 4kb directly from a block device?

How can I read more than 4kb directly from a block device?

Post by wong tsan » Sat, 22 Dec 2001 21:27:10



Dear all,
        I have problem to read more than 4kb data by using bread().
So I try to use getblk() to initialize an array of buffer_head of data
size 4kb each and then pass to ll_rw_block() to get the data.
        But I find that the I/O performance is very bad. I want to know
how I can using bread(), or getblk() + ll_rw_block() to read more than
4kb data from block device efficiently. Would anyone help me?
        Thanks in advance!

Wong Tsang

 
 
 
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1. Is there any method to read more than 4kb from block device?

Dear all,

        I have the problem to pass the buffer_head to
ll_rw_block() to read more than 4kb from block device.
I found out that the problem happened in getblk() which
does not allow the requested size greater than PAGE_SIZE(4kb).

        I would like to know if there is a method to read
more than 4kb data from block device. The retrieved data will
be used in the kernel mode.
        Thanks in advance!

Wong Tsang

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