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freebsd-dev/sys/ufs/ffs/ffs_rawread.c

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Add support for reading directly from file to userland buffer when the O_DIRECT descriptor status flag is set and both offset and length is a multiple of the physical media sector size.
2003-03-26 23:40:42 +00:00
/*-
* Copyright (c) 2000-2003 Tor Egge
* All rights reserved.
*
* Redistribution and use in source and binary forms, with or without
* modification, are permitted provided that the following conditions
* are met:
* 1. Redistributions of source code must retain the above copyright
* notice, this list of conditions and the following disclaimer.
* 2. Redistributions in binary form must reproduce the above copyright
* notice, this list of conditions and the following disclaimer in the
* documentation and/or other materials provided with the distribution.
*
* THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS'' AND
* ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
* IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
* ARE DISCLAIMED. IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE
* FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
* DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
* OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
* HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
* LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
* OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
* SUCH DAMAGE.
*/
Use __FBSDID().
2003-06-11 06:34:30 +00:00
#include <sys/cdefs.h>
__FBSDID("$FreeBSD$");
Add support for reading directly from file to userland buffer when the O_DIRECT descriptor status flag is set and both offset and length is a multiple of the physical media sector size.
2003-03-26 23:40:42 +00:00
#include <sys/param.h>
#include <sys/systm.h>
#include <sys/fcntl.h>
#include <sys/file.h>
#include <sys/stat.h>
#include <sys/proc.h>
Deprecate machine/limits.h in favor of new sys/limits.h. Change all in-tree consumers to include <sys/limits.h> Discussed on: standards@ Partially submitted by: Craig Rodrigues <rodrigc@attbi.com>
2003-04-29 13:36:06 +00:00
#include <sys/limits.h>
Add support for reading directly from file to userland buffer when the O_DIRECT descriptor status flag is set and both offset and length is a multiple of the physical media sector size.
2003-03-26 23:40:42 +00:00
#include <sys/mount.h>
#include <sys/namei.h>
#include <sys/vnode.h>
#include <sys/conf.h>
#include <sys/filio.h>
#include <sys/ttycom.h>
#include <sys/bio.h>
#include <sys/buf.h>
Revision 1.44 of ufs/ufs/inode.h has made it necessary to add two new #includes to this file. Otherwise, it doesn't compile.
2003-08-16 06:15:17 +00:00
#include <ufs/ufs/extattr.h>
Add support for reading directly from file to userland buffer when the O_DIRECT descriptor status flag is set and both offset and length is a multiple of the physical media sector size.
2003-03-26 23:40:42 +00:00
#include <ufs/ufs/quota.h>
#include <ufs/ufs/inode.h>
Revision 1.44 of ufs/ufs/inode.h has made it necessary to add two new #includes to this file. Otherwise, it doesn't compile.
2003-08-16 06:15:17 +00:00
#include <ufs/ufs/ufsmount.h>
The previous change necessitates the addition of a new #include. Otherwise, there is a compilation warning.
2003-08-18 17:27:08 +00:00
#include <ufs/ufs/ufs_extern.h>
Add support for reading directly from file to userland buffer when the O_DIRECT descriptor status flag is set and both offset and length is a multiple of the physical media sector size.
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#include <ufs/ffs/fs.h>
#include <vm/vm.h>
#include <vm/vm_extern.h>
#include <vm/vm_object.h>
#include <sys/kernel.h>
#include <sys/sysctl.h>
static int ffs_rawread_readahead(struct vnode *vp,
caddr_t udata,
off_t offset,
size_t len,
struct thread *td,
struct buf *bp,
caddr_t sa);
static int ffs_rawread_main(struct vnode *vp,
struct uio *uio);
static int ffs_rawread_sync(struct vnode *vp, struct thread *td);
int ffs_rawread(struct vnode *vp, struct uio *uio, int *workdone);
void ffs_rawread_setup(void);
static void ffs_rawreadwakeup(struct buf *bp);
SYSCTL_DECL(_vfs_ffs);
static int ffsrawbufcnt = 4;
SYSCTL_INT(_vfs_ffs, OID_AUTO, ffsrawbufcnt, CTLFLAG_RD, &ffsrawbufcnt, 0,
"Buffers available for raw reads");
static int allowrawread = 1;
SYSCTL_INT(_vfs_ffs, OID_AUTO, allowrawread, CTLFLAG_RW, &allowrawread, 0,
"Flag to enable raw reads");
static int rawreadahead = 1;
SYSCTL_INT(_vfs_ffs, OID_AUTO, rawreadahead, CTLFLAG_RW, &rawreadahead, 0,
"Flag to enable readahead for long raw reads");
void
ffs_rawread_setup(void)
{
ffsrawbufcnt = (nswbuf > 100 ) ? (nswbuf - (nswbuf >> 4)) : nswbuf - 8;
}
static int
ffs_rawread_sync(struct vnode *vp, struct thread *td)
{
int spl;
int error;
int upgraded;
Loose the v_dirty* and v_clean* alias macros. Check the count field where we just want to know the full/empty state, rather than using TAILQ_EMPTY() or TAILQ_FIRST().
2004-10-25 09:14:03 +00:00
struct bufobj *bo;
Add support for reading directly from file to userland buffer when the O_DIRECT descriptor status flag is set and both offset and length is a multiple of the physical media sector size.
2003-03-26 23:40:42 +00:00
GIANT_REQUIRED;
/* Check for dirty mmap, pending writes and dirty buffers */
spl = splbio();
VI_LOCK(vp);
Loose the v_dirty* and v_clean* alias macros. Check the count field where we just want to know the full/empty state, rather than using TAILQ_EMPTY() or TAILQ_FIRST().
2004-10-25 09:14:03 +00:00
bo = &vp->v_bufobj;
if (bo->bo_numoutput > 0 ||
Fix syntax errors introduced by last commit. Why isn't DIRECTIO in NOTES/LINT ?
2004-10-26 09:04:20 +00:00
bo->bo_dirty.bv_cnt > 0 ||
Add support for reading directly from file to userland buffer when the O_DIRECT descriptor status flag is set and both offset and length is a multiple of the physical media sector size.
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(vp->v_iflag & VI_OBJDIRTY) != 0) {
splx(spl);
VI_UNLOCK(vp);
if (VOP_ISLOCKED(vp, td) != LK_EXCLUSIVE) {
upgraded = 1;
/* Upgrade to exclusive lock, this might block */
VOP_LOCK(vp, LK_UPGRADE | LK_NOPAUSE, td);
} else
upgraded = 0;
/* Attempt to msync mmap() regions to clean dirty mmap */
VI_LOCK(vp);
if ((vp->v_iflag & VI_OBJDIRTY) != 0) {
struct vm_object *obj;
VI_UNLOCK(vp);
Lock the vm object when performing vm_object_page_clean(). Approved by: re (rwatson)
2003-05-18 22:02:51 +00:00
if (VOP_GETVOBJECT(vp, &obj) == 0) {
VM_OBJECT_LOCK(obj);
Add support for reading directly from file to userland buffer when the O_DIRECT descriptor status flag is set and both offset and length is a multiple of the physical media sector size.
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vm_object_page_clean(obj, 0, 0, OBJPC_SYNC);
Lock the vm object when performing vm_object_page_clean(). Approved by: re (rwatson)
2003-05-18 22:02:51 +00:00
VM_OBJECT_UNLOCK(obj);
}
Add support for reading directly from file to userland buffer when the O_DIRECT descriptor status flag is set and both offset and length is a multiple of the physical media sector size.
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VI_LOCK(vp);
}
/* Wait for pending writes to complete */
spl = splbio();
Loose the v_dirty* and v_clean* alias macros. Check the count field where we just want to know the full/empty state, rather than using TAILQ_EMPTY() or TAILQ_FIRST().
2004-10-25 09:14:03 +00:00
error = bufobj_wwait(&vp->v_bufobj, 0, 0);
if (error != 0) {
/* XXX: can't happen with a zero timeout ??? */
splx(spl);
VI_UNLOCK(vp);
if (upgraded != 0)
VOP_LOCK(vp, LK_DOWNGRADE, td);
return (error);
Add support for reading directly from file to userland buffer when the O_DIRECT descriptor status flag is set and both offset and length is a multiple of the physical media sector size.
2003-03-26 23:40:42 +00:00
}
/* Flush dirty buffers */
Fix syntax errors introduced by last commit. Why isn't DIRECTIO in NOTES/LINT ?
2004-10-26 09:04:20 +00:00
if (bo->bo_dirty.bv_cnt > 0) {
Add support for reading directly from file to userland buffer when the O_DIRECT descriptor status flag is set and both offset and length is a multiple of the physical media sector size.
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splx(spl);
VI_UNLOCK(vp);
Remove the unused credential argument from VOP_FSYNC() and VFS_SYNC(). I'm not sure why a credential was added to these in the first place, it is not used anywhere and it doesn't make much sense: The credentials for syncing a file (ability to write to the file) should be checked at the system call level. Credentials for syncing one or more filesystems ("none") should be checked at the system call level as well. If the filesystem implementation needs a particular credential to carry out the syncing it would logically have to the cached mount credential, or a credential cached along with any delayed write data. Discussed with: rwatson
2005-01-11 07:36:22 +00:00
if ((error = VOP_FSYNC(vp, MNT_WAIT, td)) != 0) {
Add support for reading directly from file to userland buffer when the O_DIRECT descriptor status flag is set and both offset and length is a multiple of the physical media sector size.
2003-03-26 23:40:42 +00:00
if (upgraded != 0)
VOP_LOCK(vp, LK_DOWNGRADE, td);
return (error);
}
VI_LOCK(vp);
spl = splbio();
Fix syntax errors introduced by last commit. Why isn't DIRECTIO in NOTES/LINT ?
2004-10-26 09:04:20 +00:00
if (bo->bo_numoutput > 0 || bo->bo_dirty.bv_cnt > 0)
Add support for reading directly from file to userland buffer when the O_DIRECT descriptor status flag is set and both offset and length is a multiple of the physical media sector size.
2003-03-26 23:40:42 +00:00
panic("ffs_rawread_sync: dirty bufs");
}
splx(spl);
VI_UNLOCK(vp);
if (upgraded != 0)
VOP_LOCK(vp, LK_DOWNGRADE, td);
} else {
splx(spl);
VI_UNLOCK(vp);
}
return 0;
}
static int
ffs_rawread_readahead(struct vnode *vp,
caddr_t udata,
off_t offset,
size_t len,
struct thread *td,
struct buf *bp,
caddr_t sa)
{
int error;
u_int iolen;
off_t blockno;
int blockoff;
int bsize;
struct vnode *dp;
int bforwards;
Don't use a VOP_*() function on our own vnodes, go directly to the relevant internal function, in this case ufs_bmaparray().
2003-08-17 19:26:03 +00:00
struct inode *ip;
ufs2_daddr_t blkno;
Add support for reading directly from file to userland buffer when the O_DIRECT descriptor status flag is set and both offset and length is a multiple of the physical media sector size.
2003-03-26 23:40:42 +00:00
GIANT_REQUIRED;
bsize = vp->v_mount->mnt_stat.f_iosize;
Don't use a VOP_*() function on our own vnodes, go directly to the relevant internal function, in this case ufs_bmaparray().
2003-08-17 19:26:03 +00:00
ip = VTOI(vp);
dp = ip->i_devvp;
Add support for reading directly from file to userland buffer when the O_DIRECT descriptor status flag is set and both offset and length is a multiple of the physical media sector size.
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iolen = ((vm_offset_t) udata) & PAGE_MASK;
bp->b_bcount = len;
if (bp->b_bcount + iolen > bp->b_kvasize) {
bp->b_bcount = bp->b_kvasize;
if (iolen != 0)
bp->b_bcount -= PAGE_SIZE;
}
Send B_PHYS out to pasture, it no longer serves any function.
2003-11-15 09:28:09 +00:00
bp->b_flags = 0; /* XXX necessary ? */
Add support for reading directly from file to userland buffer when the O_DIRECT descriptor status flag is set and both offset and length is a multiple of the physical media sector size.
2003-03-26 23:40:42 +00:00
bp->b_iocmd = BIO_READ;
bp->b_iodone = ffs_rawreadwakeup;
bp->b_data = udata;
bp->b_saveaddr = sa;
Initialize bp->b_offset to the physical offset in partition so GEOM knows where to read from disk.
2003-10-22 18:57:59 +00:00
blockno = offset / bsize;
blockoff = (offset % bsize) / DEV_BSIZE;
Add support for reading directly from file to userland buffer when the O_DIRECT descriptor status flag is set and both offset and length is a multiple of the physical media sector size.
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if ((daddr_t) blockno != blockno) {
return EINVAL; /* blockno overflow */
}
bp->b_lblkno = bp->b_blkno = blockno;
Don't use a VOP_*() function on our own vnodes, go directly to the relevant internal function, in this case ufs_bmaparray().
2003-08-17 19:26:03 +00:00
error = ufs_bmaparray(vp, bp->b_lblkno, &blkno, NULL, &bforwards, NULL);
if (error != 0)
Add support for reading directly from file to userland buffer when the O_DIRECT descriptor status flag is set and both offset and length is a multiple of the physical media sector size.
2003-03-26 23:40:42 +00:00
return error;
Initialize bp->b_offset to the physical offset in partition so GEOM knows where to read from disk.
2003-10-22 18:57:59 +00:00
if (blkno == -1) {
Add support for reading directly from file to userland buffer when the O_DIRECT descriptor status flag is set and both offset and length is a multiple of the physical media sector size.
2003-03-26 23:40:42 +00:00
/* Fill holes with NULs to preserve semantics */
if (bp->b_bcount + blockoff * DEV_BSIZE > bsize)
bp->b_bcount = bsize - blockoff * DEV_BSIZE;
bp->b_bufsize = bp->b_bcount;
if (vmapbuf(bp) < 0)
return EFAULT;
if (ticks - PCPU_GET(switchticks) >= hogticks)
uio_yield();
bzero(bp->b_data, bp->b_bufsize);
/* Mark operation completed (similar to bufdone()) */
bp->b_resid = 0;
bp->b_flags |= B_DONE;
return 0;
}
Initialize bp->b_offset to the physical offset in partition so GEOM knows where to read from disk.
2003-10-22 18:57:59 +00:00
bp->b_blkno = blkno + blockoff;
bp->b_offset = bp->b_iooffset = (blkno + blockoff) * DEV_BSIZE;
Add support for reading directly from file to userland buffer when the O_DIRECT descriptor status flag is set and both offset and length is a multiple of the physical media sector size.
2003-03-26 23:40:42 +00:00
if (bp->b_bcount + blockoff * DEV_BSIZE > bsize * (1 + bforwards))
bp->b_bcount = bsize * (1 + bforwards) - blockoff * DEV_BSIZE;
bp->b_bufsize = bp->b_bcount;
Check return value from vmapbuf instead of the function address.
2003-03-27 20:48:34 +00:00
if (vmapbuf(bp) < 0)
Add support for reading directly from file to userland buffer when the O_DIRECT descriptor status flag is set and both offset and length is a multiple of the physical media sector size.
2003-03-26 23:40:42 +00:00
return EFAULT;
Move UFS from DEVFS backing to GEOM backing. This eliminates a bunch of vnode overhead (approx 1-2 % speed improvement) and gives us more control over the access to the storage device. Access counts on the underlying device are not correctly tracked and therefore it is possible to read-only mount the same disk device multiple times: syv# mount -p /dev/md0 /var ufs rw 2 2 /dev/ad0 /mnt ufs ro 1 1 /dev/ad0 /mnt2 ufs ro 1 1 /dev/ad0 /mnt3 ufs ro 1 1 Since UFS/FFS is not a synchrousely consistent filesystem (ie: it caches things in RAM) this is not possible with read-write mounts, and the system will correctly reject this. Details: Add a geom consumer and a bufobj pointer to ufsmount. Eliminate the vnode argument from softdep_disk_prewrite(). Pick the vnode out of bp->b_vp for now. Eventually we should find it through bp->b_bufobj->b_private. In the mountcode, use g_vfs_open() once we have used VOP_ACCESS() to check permissions. When upgrading and downgrading between r/o and r/w do the right thing with GEOM access counts. Remove all the workarounds for not being able to do this with VOP_OPEN(). If we are the root mount, drop the exclusive access count until we upgrade to r/w. This allows fsck of the root filesystem and the MNT_RELOAD to work correctly. Set bo_private to the GEOM consumer on the device bufobj. Change the ffs_ops->strategy function to call g_vfs_strategy() In ufs_strategy() directly call the strategy on the disk bufobj. Same in rawread. In ffs_fsync() we will no longer see VCHR device nodes, so remove code which synced the filesystem mounted on it, in case we came there. I'm not sure this code made sense in the first place since we would have taken the specfs route on such a vnode. Redo the highly bogus readblock() function in the snapshot code to something slightly less bogus: Constructing an uio and using physio was really quite a detour. Instead just fill in a bio and ship it down.
2004-10-29 10:15:56 +00:00
dp->v_bufobj.bo_ops->bop_strategy(&dp->v_bufobj, bp);
Add support for reading directly from file to userland buffer when the O_DIRECT descriptor status flag is set and both offset and length is a multiple of the physical media sector size.
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return 0;
}
static int
ffs_rawread_main(struct vnode *vp,
struct uio *uio)
{
int error, nerror;
struct buf *bp, *nbp, *tbp;
caddr_t sa, nsa, tsa;
u_int iolen;
int spl;
caddr_t udata;
long resid;
off_t offset;
struct thread *td;
GIANT_REQUIRED;
td = uio->uio_td ? uio->uio_td : curthread;
udata = uio->uio_iov->iov_base;
resid = uio->uio_resid;
offset = uio->uio_offset;
/*
* keep the process from being swapped
*/
PHOLD(td->td_proc);
error = 0;
nerror = 0;
bp = NULL;
nbp = NULL;
sa = NULL;
nsa = NULL;
while (resid > 0) {
if (bp == NULL) { /* Setup first read */
/* XXX: Leave some bufs for swap */
bp = getpbuf(&ffsrawbufcnt);
sa = bp->b_data;
bp->b_vp = vp;
error = ffs_rawread_readahead(vp, udata, offset,
resid, td, bp, sa);
if (error != 0)
break;
if (resid > bp->b_bufsize) { /* Setup fist readahead */
/* XXX: Leave bufs for swap */
if (rawreadahead != 0)
nbp = trypbuf(&ffsrawbufcnt);
else
nbp = NULL;
if (nbp != NULL) {
nsa = nbp->b_data;
nbp->b_vp = vp;
nerror = ffs_rawread_readahead(vp,
udata +
bp->b_bufsize,
offset +
bp->b_bufsize,
resid -
bp->b_bufsize,
td,
nbp,
nsa);
if (nerror) {
relpbuf(nbp, &ffsrawbufcnt);
nbp = NULL;
}
}
}
}
spl = splbio();
Eliminate a buffer sleep/wakeup race.
2003-03-27 19:28:11 +00:00
bwait(bp, PRIBIO, "rawrd");
Add support for reading directly from file to userland buffer when the O_DIRECT descriptor status flag is set and both offset and length is a multiple of the physical media sector size.
2003-03-26 23:40:42 +00:00
splx(spl);
vunmapbuf(bp);
iolen = bp->b_bcount - bp->b_resid;
if (iolen == 0 && (bp->b_ioflags & BIO_ERROR) == 0) {
nerror = 0; /* Ignore possible beyond EOF error */
break; /* EOF */
}
if ((bp->b_ioflags & BIO_ERROR) != 0) {
error = bp->b_error;
break;
}
resid -= iolen;
udata += iolen;
offset += iolen;
if (iolen < bp->b_bufsize) {
/* Incomplete read. Try to read remaining part */
error = ffs_rawread_readahead(vp,
udata,
offset,
bp->b_bufsize - iolen,
td,
bp,
sa);
if (error != 0)
break;
} else if (nbp != NULL) { /* Complete read with readahead */
tbp = bp;
bp = nbp;
nbp = tbp;
tsa = sa;
sa = nsa;
nsa = tsa;
if (resid <= bp->b_bufsize) { /* No more readaheads */
relpbuf(nbp, &ffsrawbufcnt);
nbp = NULL;
} else { /* Setup next readahead */
nerror = ffs_rawread_readahead(vp,
udata +
bp->b_bufsize,
offset +
bp->b_bufsize,
resid -
bp->b_bufsize,
td,
nbp,
nsa);
if (nerror != 0) {
relpbuf(nbp, &ffsrawbufcnt);
nbp = NULL;
}
}
} else if (nerror != 0) {/* Deferred Readahead error */
break;
} else if (resid > 0) { /* More to read, no readahead */
error = ffs_rawread_readahead(vp, udata, offset,
resid, td, bp, sa);
if (error != 0)
break;
}
}
if (bp != NULL)
relpbuf(bp, &ffsrawbufcnt);
if (nbp != NULL) { /* Run down readahead buffer */
spl = splbio();
Eliminate a buffer sleep/wakeup race.
2003-03-27 19:28:11 +00:00
bwait(nbp, PRIBIO, "rawrd");
Add support for reading directly from file to userland buffer when the O_DIRECT descriptor status flag is set and both offset and length is a multiple of the physical media sector size.
2003-03-26 23:40:42 +00:00
splx(spl);
vunmapbuf(nbp);
relpbuf(nbp, &ffsrawbufcnt);
}
if (error == 0)
error = nerror;
PRELE(td->td_proc);
uio->uio_iov->iov_base = udata;
uio->uio_resid = resid;
uio->uio_offset = offset;
return error;
}
int
ffs_rawread(struct vnode *vp,
struct uio *uio,
int *workdone)
{
if (allowrawread != 0 &&
uio->uio_iovcnt == 1 &&
uio->uio_segflg == UIO_USERSPACE &&
uio->uio_resid == uio->uio_iov->iov_len &&
Move TDF_DEADLKTREAT into td_pflags (and rename it accordingly) to avoid having to acquire sched_lock when manipulating it in lockmgr(), uiomove(), and uiomove_fromphys(). Reviewed by: jhb
2004-06-03 01:47:37 +00:00
(((uio->uio_td != NULL) ? uio->uio_td : curthread)->td_pflags &
TDP_DEADLKTREAT) == 0) {
Add support for reading directly from file to userland buffer when the O_DIRECT descriptor status flag is set and both offset and length is a multiple of the physical media sector size.
2003-03-26 23:40:42 +00:00
int secsize; /* Media sector size */
off_t filebytes; /* Bytes left of file */
int blockbytes; /* Bytes left of file in full blocks */
int partialbytes; /* Bytes in last partial block */
int skipbytes; /* Bytes not to read in ffs_rawread */
struct inode *ip;
int error;
/* Only handle sector aligned reads */
ip = VTOI(vp);
Put the I/O block size in bufobj->bo_bsize. We keep si_bsize_phys around for now as that is the simplest way to pull the number out of disk device drivers in devfs_open(). The correct solution would be to do an ioctl(DIOCGSECTORSIZE), but the point is probably mooth when filesystems sit on GEOM, so don't bother for now.
2004-10-26 07:39:12 +00:00
secsize = ip->i_devvp->v_bufobj.bo_bsize;
Add support for reading directly from file to userland buffer when the O_DIRECT descriptor status flag is set and both offset and length is a multiple of the physical media sector size.
2003-03-26 23:40:42 +00:00
if ((uio->uio_offset & (secsize - 1)) == 0 &&
(uio->uio_resid & (secsize - 1)) == 0) {
/* Sync dirty pages and buffers if needed */
error = ffs_rawread_sync(vp,
(uio->uio_td != NULL) ?
uio->uio_td : curthread);
if (error != 0)
return error;
/* Check for end of file */
if (ip->i_size > uio->uio_offset) {
filebytes = ip->i_size - uio->uio_offset;
/* No special eof handling needed ? */
if (uio->uio_resid <= filebytes) {
*workdone = 1;
return ffs_rawread_main(vp, uio);
}
partialbytes = ((unsigned int) ip->i_size) %
ip->i_fs->fs_bsize;
blockbytes = (int) filebytes - partialbytes;
if (blockbytes > 0) {
skipbytes = uio->uio_resid -
blockbytes;
uio->uio_resid = blockbytes;
error = ffs_rawread_main(vp, uio);
uio->uio_resid += skipbytes;
if (error != 0)
return error;
/* Read remaining part using buffer */
}
}
}
}
*workdone = 0;
return 0;
}
static void
ffs_rawreadwakeup(struct buf *bp)
{
Eliminate a buffer sleep/wakeup race.
2003-03-27 19:28:11 +00:00
bdone(bp);
Add support for reading directly from file to userland buffer when the O_DIRECT descriptor status flag is set and both offset and length is a multiple of the physical media sector size.
2003-03-26 23:40:42 +00:00
}
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