563 lines
18 KiB
C
563 lines
18 KiB
C
/* This file contains the heart of the mechanism used to read (and write)
|
|
* files. Read and write requests are split up into chunks that do not cross
|
|
* block boundaries. Each chunk is then processed in turn. Reads on special
|
|
* files are also detected and handled.
|
|
*
|
|
* The entry points into this file are
|
|
* do_read: perform the READ system call by calling read_write
|
|
* read_write: actually do the work of READ and WRITE
|
|
* read_map: given an inode and file position, look up its zone number
|
|
* rd_indir: read an entry in an indirect block
|
|
* read_ahead: manage the block read ahead business
|
|
*/
|
|
|
|
#include "fs.h"
|
|
#include <fcntl.h>
|
|
#include <minix/com.h>
|
|
#include "buf.h"
|
|
#include "file.h"
|
|
#include "fproc.h"
|
|
#include "inode.h"
|
|
#include "param.h"
|
|
#include "super.h"
|
|
|
|
FORWARD _PROTOTYPE( int rw_chunk, (struct inode *rip, off_t position,
|
|
unsigned off, int chunk, unsigned left, int rw_flag,
|
|
char *buff, int seg, int usr, int block_size, int *completed));
|
|
|
|
/*===========================================================================*
|
|
* do_read *
|
|
*===========================================================================*/
|
|
PUBLIC int do_read()
|
|
{
|
|
return(read_write(READING));
|
|
}
|
|
|
|
/*===========================================================================*
|
|
* read_write *
|
|
*===========================================================================*/
|
|
PUBLIC int read_write(rw_flag)
|
|
int rw_flag; /* READING or WRITING */
|
|
{
|
|
/* Perform read(fd, buffer, nbytes) or write(fd, buffer, nbytes) call. */
|
|
|
|
register struct inode *rip;
|
|
register struct filp *f;
|
|
off_t bytes_left, f_size, position;
|
|
unsigned int off, cum_io;
|
|
int op, oflags, r, chunk, usr, seg, block_spec, char_spec;
|
|
int regular, partial_pipe = 0, partial_cnt = 0;
|
|
mode_t mode_word;
|
|
struct filp *wf;
|
|
int block_size;
|
|
int completed, r2 = OK;
|
|
phys_bytes p;
|
|
|
|
/* left unfinished rw_chunk()s from previous call! this can't happen.
|
|
* it means something has gone wrong we can't repair now.
|
|
*/
|
|
if(bufs_in_use < 0) {
|
|
panic(__FILE__,"start - bufs_in_use negative", bufs_in_use);
|
|
}
|
|
|
|
/* MM loads segments by putting funny things in upper 10 bits of 'fd'. */
|
|
if (who == PM_PROC_NR && (m_in.fd & (~BYTE)) ) {
|
|
usr = m_in.fd >> 7;
|
|
seg = (m_in.fd >> 5) & 03;
|
|
m_in.fd &= 037; /* get rid of user and segment bits */
|
|
} else {
|
|
usr = who; /* normal case */
|
|
seg = D;
|
|
}
|
|
|
|
/* If the file descriptor is valid, get the inode, size and mode. */
|
|
if (m_in.nbytes < 0) return(EINVAL);
|
|
if ((f = get_filp(m_in.fd)) == NIL_FILP) return(err_code);
|
|
if (((f->filp_mode) & (rw_flag == READING ? R_BIT : W_BIT)) == 0) {
|
|
return(f->filp_mode == FILP_CLOSED ? EIO : EBADF);
|
|
}
|
|
if (m_in.nbytes == 0)
|
|
return(0); /* so char special files need not check for 0*/
|
|
|
|
/* check if user process has the memory it needs.
|
|
* if not, copying will fail later.
|
|
* do this after 0-check above because umap doesn't want to map 0 bytes.
|
|
*/
|
|
if ((r = sys_umap(usr, seg, (vir_bytes) m_in.buffer, m_in.nbytes, &p)) != OK)
|
|
return r;
|
|
position = f->filp_pos;
|
|
oflags = f->filp_flags;
|
|
rip = f->filp_ino;
|
|
f_size = rip->i_size;
|
|
r = OK;
|
|
if (rip->i_pipe == I_PIPE) {
|
|
/* fp->fp_cum_io_partial is only nonzero when doing partial writes */
|
|
cum_io = fp->fp_cum_io_partial;
|
|
} else {
|
|
cum_io = 0;
|
|
}
|
|
op = (rw_flag == READING ? DEV_READ : DEV_WRITE);
|
|
mode_word = rip->i_mode & I_TYPE;
|
|
regular = mode_word == I_REGULAR || mode_word == I_NAMED_PIPE;
|
|
|
|
if((char_spec = (mode_word == I_CHAR_SPECIAL ? 1 : 0))) {
|
|
if(rip->i_zone[0] == NO_DEV)
|
|
panic(__FILE__,"read_write tries to read from "
|
|
"character device NO_DEV", NO_NUM);
|
|
block_size = get_block_size(rip->i_zone[0]);
|
|
}
|
|
if((block_spec = (mode_word == I_BLOCK_SPECIAL ? 1 : 0))) {
|
|
f_size = ULONG_MAX;
|
|
if(rip->i_zone[0] == NO_DEV)
|
|
panic(__FILE__,"read_write tries to read from "
|
|
" block device NO_DEV", NO_NUM);
|
|
block_size = get_block_size(rip->i_zone[0]);
|
|
}
|
|
|
|
if(!char_spec && !block_spec)
|
|
block_size = rip->i_sp->s_block_size;
|
|
|
|
rdwt_err = OK; /* set to EIO if disk error occurs */
|
|
|
|
/* Check for character special files. */
|
|
if (char_spec) {
|
|
dev_t dev;
|
|
dev = (dev_t) rip->i_zone[0];
|
|
r = dev_io(op, dev, usr, m_in.buffer, position, m_in.nbytes, oflags);
|
|
if (r >= 0) {
|
|
cum_io = r;
|
|
position += r;
|
|
r = OK;
|
|
}
|
|
} else {
|
|
if (rw_flag == WRITING && block_spec == 0) {
|
|
/* Check in advance to see if file will grow too big. */
|
|
if (position > rip->i_sp->s_max_size - m_in.nbytes)
|
|
return(EFBIG);
|
|
|
|
/* Check for O_APPEND flag. */
|
|
if (oflags & O_APPEND) position = f_size;
|
|
|
|
/* Clear the zone containing present EOF if hole about
|
|
* to be created. This is necessary because all unwritten
|
|
* blocks prior to the EOF must read as zeros.
|
|
*/
|
|
if (position > f_size) clear_zone(rip, f_size, 0);
|
|
}
|
|
|
|
/* Pipes are a little different. Check. */
|
|
if (rip->i_pipe == I_PIPE) {
|
|
r = pipe_check(rip, rw_flag, oflags,
|
|
m_in.nbytes, position, &partial_cnt, 0);
|
|
if (r <= 0) return(r);
|
|
}
|
|
|
|
if (partial_cnt > 0) partial_pipe = 1;
|
|
|
|
/* Split the transfer into chunks that don't span two blocks. */
|
|
while (m_in.nbytes != 0) {
|
|
|
|
off = (unsigned int) (position % block_size);/* offset in blk*/
|
|
if (partial_pipe) { /* pipes only */
|
|
chunk = MIN(partial_cnt, block_size - off);
|
|
} else
|
|
chunk = MIN(m_in.nbytes, block_size - off);
|
|
if (chunk < 0) chunk = block_size - off;
|
|
|
|
if (rw_flag == READING) {
|
|
bytes_left = f_size - position;
|
|
if (position >= f_size) break; /* we are beyond EOF */
|
|
if (chunk > bytes_left) chunk = (int) bytes_left;
|
|
}
|
|
|
|
/* Read or write 'chunk' bytes. */
|
|
r = rw_chunk(rip, position, off, chunk, (unsigned) m_in.nbytes,
|
|
rw_flag, m_in.buffer, seg, usr, block_size, &completed);
|
|
|
|
if (r != OK) break; /* EOF reached */
|
|
if (rdwt_err < 0) break;
|
|
|
|
/* Update counters and pointers. */
|
|
m_in.buffer += chunk; /* user buffer address */
|
|
m_in.nbytes -= chunk; /* bytes yet to be read */
|
|
cum_io += chunk; /* bytes read so far */
|
|
position += chunk; /* position within the file */
|
|
|
|
if (partial_pipe) {
|
|
partial_cnt -= chunk;
|
|
if (partial_cnt <= 0) break;
|
|
}
|
|
}
|
|
}
|
|
|
|
/* On write, update file size and access time. */
|
|
if (rw_flag == WRITING) {
|
|
if (regular || mode_word == I_DIRECTORY) {
|
|
if (position > f_size) rip->i_size = position;
|
|
}
|
|
} else {
|
|
if (rip->i_pipe == I_PIPE) {
|
|
if( position >= rip->i_size) {
|
|
/* Reset pipe pointers. */
|
|
rip->i_size = 0; /* no data left */
|
|
position = 0; /* reset reader(s) */
|
|
wf = find_filp(rip, W_BIT);
|
|
if (wf != NIL_FILP) wf->filp_pos = 0;
|
|
}
|
|
}
|
|
}
|
|
f->filp_pos = position;
|
|
|
|
/* Check to see if read-ahead is called for, and if so, set it up. */
|
|
if (rw_flag == READING && rip->i_seek == NO_SEEK && position % block_size== 0
|
|
&& (regular || mode_word == I_DIRECTORY)) {
|
|
rdahed_inode = rip;
|
|
rdahedpos = position;
|
|
}
|
|
rip->i_seek = NO_SEEK;
|
|
|
|
if (rdwt_err != OK) r = rdwt_err; /* check for disk error */
|
|
if (rdwt_err == END_OF_FILE) r = OK;
|
|
|
|
/* if user-space copying failed, read/write failed. */
|
|
if (r == OK && r2 != OK) {
|
|
r = r2;
|
|
}
|
|
if (r == OK) {
|
|
if (rw_flag == READING) rip->i_update |= ATIME;
|
|
if (rw_flag == WRITING) rip->i_update |= CTIME | MTIME;
|
|
rip->i_dirt = DIRTY; /* inode is thus now dirty */
|
|
if (partial_pipe) {
|
|
partial_pipe = 0;
|
|
/* partial write on pipe with */
|
|
/* O_NONBLOCK, return write count */
|
|
if (!(oflags & O_NONBLOCK)) {
|
|
fp->fp_cum_io_partial = cum_io;
|
|
suspend(XPIPE); /* partial write on pipe with */
|
|
return(SUSPEND); /* nbyte > PIPE_SIZE - non-atomic */
|
|
}
|
|
}
|
|
fp->fp_cum_io_partial = 0;
|
|
return(cum_io);
|
|
}
|
|
if(bufs_in_use < 0) {
|
|
panic(__FILE__,"end - bufs_in_use negative", bufs_in_use);
|
|
}
|
|
return(r);
|
|
}
|
|
|
|
/*===========================================================================*
|
|
* rw_chunk *
|
|
*===========================================================================*/
|
|
PRIVATE int rw_chunk(rip, position, off, chunk, left, rw_flag, buff,
|
|
seg, usr, block_size, completed)
|
|
register struct inode *rip; /* pointer to inode for file to be rd/wr */
|
|
off_t position; /* position within file to read or write */
|
|
unsigned off; /* off within the current block */
|
|
int chunk; /* number of bytes to read or write */
|
|
unsigned left; /* max number of bytes wanted after position */
|
|
int rw_flag; /* READING or WRITING */
|
|
char *buff; /* virtual address of the user buffer */
|
|
int seg; /* T or D segment in user space */
|
|
int usr; /* which user process */
|
|
int block_size; /* block size of FS operating on */
|
|
int *completed; /* number of bytes copied */
|
|
{
|
|
/* Read or write (part of) a block. */
|
|
|
|
register struct buf *bp;
|
|
register int r = OK;
|
|
int n, block_spec;
|
|
block_t b;
|
|
dev_t dev;
|
|
|
|
*completed = 0;
|
|
|
|
block_spec = (rip->i_mode & I_TYPE) == I_BLOCK_SPECIAL;
|
|
if (block_spec) {
|
|
b = position/block_size;
|
|
dev = (dev_t) rip->i_zone[0];
|
|
} else {
|
|
b = read_map(rip, position);
|
|
dev = rip->i_dev;
|
|
}
|
|
|
|
if (!block_spec && b == NO_BLOCK) {
|
|
if (rw_flag == READING) {
|
|
/* Reading from a nonexistent block. Must read as all zeros.*/
|
|
bp = get_block(NO_DEV, NO_BLOCK, NORMAL); /* get a buffer */
|
|
zero_block(bp);
|
|
} else {
|
|
/* Writing to a nonexistent block. Create and enter in inode.*/
|
|
if ((bp= new_block(rip, position)) == NIL_BUF)return(err_code);
|
|
}
|
|
} else if (rw_flag == READING) {
|
|
/* Read and read ahead if convenient. */
|
|
bp = rahead(rip, b, position, left);
|
|
} else {
|
|
/* Normally an existing block to be partially overwritten is first read
|
|
* in. However, a full block need not be read in. If it is already in
|
|
* the cache, acquire it, otherwise just acquire a free buffer.
|
|
*/
|
|
n = (chunk == block_size ? NO_READ : NORMAL);
|
|
if (!block_spec && off == 0 && position >= rip->i_size) n = NO_READ;
|
|
bp = get_block(dev, b, n);
|
|
}
|
|
|
|
/* In all cases, bp now points to a valid buffer. */
|
|
if(bp == NIL_BUF) {
|
|
panic(__FILE__,"bp not valid in rw_chunk, this can't happen", NO_NUM);
|
|
}
|
|
if (rw_flag == WRITING && chunk != block_size && !block_spec &&
|
|
position >= rip->i_size && off == 0) {
|
|
zero_block(bp);
|
|
}
|
|
|
|
if (rw_flag == READING) {
|
|
/* Copy a chunk from the block buffer to user space. */
|
|
r = sys_vircopy(FS_PROC_NR, D, (phys_bytes) (bp->b_data+off),
|
|
usr, seg, (phys_bytes) buff,
|
|
(phys_bytes) chunk);
|
|
} else {
|
|
/* Copy a chunk from user space to the block buffer. */
|
|
r = sys_vircopy(usr, seg, (phys_bytes) buff,
|
|
FS_PROC_NR, D, (phys_bytes) (bp->b_data+off),
|
|
(phys_bytes) chunk);
|
|
bp->b_dirt = DIRTY;
|
|
}
|
|
n = (off + chunk == block_size ? FULL_DATA_BLOCK : PARTIAL_DATA_BLOCK);
|
|
put_block(bp, n);
|
|
|
|
return(r);
|
|
}
|
|
|
|
|
|
/*===========================================================================*
|
|
* read_map *
|
|
*===========================================================================*/
|
|
PUBLIC block_t read_map(rip, position)
|
|
register struct inode *rip; /* ptr to inode to map from */
|
|
off_t position; /* position in file whose blk wanted */
|
|
{
|
|
/* Given an inode and a position within the corresponding file, locate the
|
|
* block (not zone) number in which that position is to be found and return it.
|
|
*/
|
|
|
|
register struct buf *bp;
|
|
register zone_t z;
|
|
int scale, boff, dzones, nr_indirects, index, zind, ex;
|
|
block_t b;
|
|
long excess, zone, block_pos;
|
|
|
|
scale = rip->i_sp->s_log_zone_size; /* for block-zone conversion */
|
|
block_pos = position/rip->i_sp->s_block_size; /* relative blk # in file */
|
|
zone = block_pos >> scale; /* position's zone */
|
|
boff = (int) (block_pos - (zone << scale) ); /* relative blk # within zone */
|
|
dzones = rip->i_ndzones;
|
|
nr_indirects = rip->i_nindirs;
|
|
|
|
/* Is 'position' to be found in the inode itself? */
|
|
if (zone < dzones) {
|
|
zind = (int) zone; /* index should be an int */
|
|
z = rip->i_zone[zind];
|
|
if (z == NO_ZONE) return(NO_BLOCK);
|
|
b = ((block_t) z << scale) + boff;
|
|
return(b);
|
|
}
|
|
|
|
/* It is not in the inode, so it must be single or double indirect. */
|
|
excess = zone - dzones; /* first Vx_NR_DZONES don't count */
|
|
|
|
if (excess < nr_indirects) {
|
|
/* 'position' can be located via the single indirect block. */
|
|
z = rip->i_zone[dzones];
|
|
} else {
|
|
/* 'position' can be located via the double indirect block. */
|
|
if ( (z = rip->i_zone[dzones+1]) == NO_ZONE) return(NO_BLOCK);
|
|
excess -= nr_indirects; /* single indir doesn't count*/
|
|
b = (block_t) z << scale;
|
|
bp = get_block(rip->i_dev, b, NORMAL); /* get double indirect block */
|
|
index = (int) (excess/nr_indirects);
|
|
z = rd_indir(bp, index); /* z= zone for single*/
|
|
put_block(bp, INDIRECT_BLOCK); /* release double ind block */
|
|
excess = excess % nr_indirects; /* index into single ind blk */
|
|
}
|
|
|
|
/* 'z' is zone num for single indirect block; 'excess' is index into it. */
|
|
if (z == NO_ZONE) return(NO_BLOCK);
|
|
b = (block_t) z << scale; /* b is blk # for single ind */
|
|
bp = get_block(rip->i_dev, b, NORMAL); /* get single indirect block */
|
|
ex = (int) excess; /* need an integer */
|
|
z = rd_indir(bp, ex); /* get block pointed to */
|
|
put_block(bp, INDIRECT_BLOCK); /* release single indir blk */
|
|
if (z == NO_ZONE) return(NO_BLOCK);
|
|
b = ((block_t) z << scale) + boff;
|
|
return(b);
|
|
}
|
|
|
|
/*===========================================================================*
|
|
* rd_indir *
|
|
*===========================================================================*/
|
|
PUBLIC zone_t rd_indir(bp, index)
|
|
struct buf *bp; /* pointer to indirect block */
|
|
int index; /* index into *bp */
|
|
{
|
|
/* Given a pointer to an indirect block, read one entry. The reason for
|
|
* making a separate routine out of this is that there are four cases:
|
|
* V1 (IBM and 68000), and V2 (IBM and 68000).
|
|
*/
|
|
|
|
struct super_block *sp;
|
|
zone_t zone; /* V2 zones are longs (shorts in V1) */
|
|
|
|
sp = get_super(bp->b_dev); /* need super block to find file sys type */
|
|
|
|
/* read a zone from an indirect block */
|
|
if (sp->s_version == V1)
|
|
zone = (zone_t) conv2(sp->s_native, (int) bp->b_v1_ind[index]);
|
|
else
|
|
zone = (zone_t) conv4(sp->s_native, (long) bp->b_v2_ind[index]);
|
|
|
|
if (zone != NO_ZONE &&
|
|
(zone < (zone_t) sp->s_firstdatazone || zone >= sp->s_zones)) {
|
|
printf("Illegal zone number %ld in indirect block, index %d\n",
|
|
(long) zone, index);
|
|
panic(__FILE__,"check file system", NO_NUM);
|
|
}
|
|
return(zone);
|
|
}
|
|
|
|
/*===========================================================================*
|
|
* read_ahead *
|
|
*===========================================================================*/
|
|
PUBLIC void read_ahead()
|
|
{
|
|
/* Read a block into the cache before it is needed. */
|
|
int block_size;
|
|
register struct inode *rip;
|
|
struct buf *bp;
|
|
block_t b;
|
|
|
|
rip = rdahed_inode; /* pointer to inode to read ahead from */
|
|
block_size = get_block_size(rip->i_dev);
|
|
rdahed_inode = NIL_INODE; /* turn off read ahead */
|
|
if ( (b = read_map(rip, rdahedpos)) == NO_BLOCK) return; /* at EOF */
|
|
bp = rahead(rip, b, rdahedpos, block_size);
|
|
put_block(bp, PARTIAL_DATA_BLOCK);
|
|
}
|
|
|
|
/*===========================================================================*
|
|
* rahead *
|
|
*===========================================================================*/
|
|
PUBLIC struct buf *rahead(rip, baseblock, position, bytes_ahead)
|
|
register struct inode *rip; /* pointer to inode for file to be read */
|
|
block_t baseblock; /* block at current position */
|
|
off_t position; /* position within file */
|
|
unsigned bytes_ahead; /* bytes beyond position for immediate use */
|
|
{
|
|
/* Fetch a block from the cache or the device. If a physical read is
|
|
* required, prefetch as many more blocks as convenient into the cache.
|
|
* This usually covers bytes_ahead and is at least BLOCKS_MINIMUM.
|
|
* The device driver may decide it knows better and stop reading at a
|
|
* cylinder boundary (or after an error). Rw_scattered() puts an optional
|
|
* flag on all reads to allow this.
|
|
*/
|
|
int block_size;
|
|
/* Minimum number of blocks to prefetch. */
|
|
# define BLOCKS_MINIMUM (NR_BUFS < 50 ? 18 : 32)
|
|
int block_spec, scale, read_q_size;
|
|
unsigned int blocks_ahead, fragment;
|
|
block_t block, blocks_left;
|
|
off_t ind1_pos;
|
|
dev_t dev;
|
|
struct buf *bp;
|
|
static struct buf *read_q[NR_BUFS];
|
|
|
|
block_spec = (rip->i_mode & I_TYPE) == I_BLOCK_SPECIAL;
|
|
if (block_spec) {
|
|
dev = (dev_t) rip->i_zone[0];
|
|
} else {
|
|
dev = rip->i_dev;
|
|
}
|
|
block_size = get_block_size(dev);
|
|
|
|
block = baseblock;
|
|
bp = get_block(dev, block, PREFETCH);
|
|
if (bp->b_dev != NO_DEV) return(bp);
|
|
|
|
/* The best guess for the number of blocks to prefetch: A lot.
|
|
* It is impossible to tell what the device looks like, so we don't even
|
|
* try to guess the geometry, but leave it to the driver.
|
|
*
|
|
* The floppy driver can read a full track with no rotational delay, and it
|
|
* avoids reading partial tracks if it can, so handing it enough buffers to
|
|
* read two tracks is perfect. (Two, because some diskette types have
|
|
* an odd number of sectors per track, so a block may span tracks.)
|
|
*
|
|
* The disk drivers don't try to be smart. With todays disks it is
|
|
* impossible to tell what the real geometry looks like, so it is best to
|
|
* read as much as you can. With luck the caching on the drive allows
|
|
* for a little time to start the next read.
|
|
*
|
|
* The current solution below is a bit of a hack, it just reads blocks from
|
|
* the current file position hoping that more of the file can be found. A
|
|
* better solution must look at the already available zone pointers and
|
|
* indirect blocks (but don't call read_map!).
|
|
*/
|
|
|
|
fragment = position % block_size;
|
|
position -= fragment;
|
|
bytes_ahead += fragment;
|
|
|
|
blocks_ahead = (bytes_ahead + block_size - 1) / block_size;
|
|
|
|
if (block_spec && rip->i_size == 0) {
|
|
blocks_left = NR_IOREQS;
|
|
} else {
|
|
blocks_left = (rip->i_size - position + block_size - 1) / block_size;
|
|
|
|
/* Go for the first indirect block if we are in its neighborhood. */
|
|
if (!block_spec) {
|
|
scale = rip->i_sp->s_log_zone_size;
|
|
ind1_pos = (off_t) rip->i_ndzones * (block_size << scale);
|
|
if (position <= ind1_pos && rip->i_size > ind1_pos) {
|
|
blocks_ahead++;
|
|
blocks_left++;
|
|
}
|
|
}
|
|
}
|
|
|
|
/* No more than the maximum request. */
|
|
if (blocks_ahead > NR_IOREQS) blocks_ahead = NR_IOREQS;
|
|
|
|
/* Read at least the minimum number of blocks, but not after a seek. */
|
|
if (blocks_ahead < BLOCKS_MINIMUM && rip->i_seek == NO_SEEK)
|
|
blocks_ahead = BLOCKS_MINIMUM;
|
|
|
|
/* Can't go past end of file. */
|
|
if (blocks_ahead > blocks_left) blocks_ahead = blocks_left;
|
|
|
|
read_q_size = 0;
|
|
|
|
/* Acquire block buffers. */
|
|
for (;;) {
|
|
read_q[read_q_size++] = bp;
|
|
|
|
if (--blocks_ahead == 0) break;
|
|
|
|
/* Don't trash the cache, leave 4 free. */
|
|
if (bufs_in_use >= NR_BUFS - 4) break;
|
|
|
|
block++;
|
|
|
|
bp = get_block(dev, block, PREFETCH);
|
|
if (bp->b_dev != NO_DEV) {
|
|
/* Oops, block already in the cache, get out. */
|
|
put_block(bp, FULL_DATA_BLOCK);
|
|
break;
|
|
}
|
|
}
|
|
rw_scattered(dev, read_q, read_q_size, READING);
|
|
return(get_block(dev, baseblock, NORMAL));
|
|
}
|