d/freebsd-dev
1
0
Fork 0
Code Issues Pull Requests Packages Projects Releases Wiki Activity

Do not acquire Giant unconditionally around the calls to the cdevsw

Browse Source 
d_mmap methods. prep_cdevsw() already installs the shims that
acquire/drop Giant for the methods of a driver that specified the
D_NEEDGIANT flag.

Reviewed by:	alc
Approved by:	re (kensmith)
This commit is contained in:
Konstantin Belousov 2007-08-05 05:40:52 +00:00
parent dd04013007
commit c6199d59e3
Notes: svn2git 2020-12-20 02:59:44 +00:00 
svn path=/head/; revision=171725
1 changed files with 0 additions and 5 deletions
Show Stats Download Patch File Download Diff File Expand all files Collapse all files

5
sys/vm/device_pager.c
View File

@ -126,7 +126,6 @@ dev_pager_alloc(void *handle, vm_ooffset_t size, vm_prot_t prot, vm_ooffset_t fo
csw = dev_refthread(dev);
if (csw == NULL)
return (NULL);
mtx_lock(&Giant);
/*
* Check that the specified range of the device allows the desired
@ -137,7 +136,6 @@ dev_pager_alloc(void *handle, vm_ooffset_t size, vm_prot_t prot, vm_ooffset_t fo
npages = OFF_TO_IDX(size);
for (off = foff; npages--; off += PAGE_SIZE)
if ((*csw->d_mmap)(dev, off, &paddr, (int)prot) != 0) {
mtx_unlock(&Giant);
dev_relthread(dev);
return (NULL);
}
@ -171,7 +169,6 @@ dev_pager_alloc(void *handle, vm_ooffset_t size, vm_prot_t prot, vm_ooffset_t fo
}
sx_xunlock(&dev_pager_sx);
mtx_unlock(&Giant);
dev_relthread(dev);
return (object);
}
@ -216,12 +213,10 @@ dev_pager_getpages(object, m, count, reqpage)
csw = dev_refthread(dev);
if (csw == NULL)
panic("dev_pager_getpage: no cdevsw");
mtx_lock(&Giant);
prot = PROT_READ; /* XXX should pass in? */
ret = (*csw->d_mmap)(dev, (vm_offset_t)offset << PAGE_SHIFT, &paddr, prot);
KASSERT(ret == 0, ("dev_pager_getpage: map function returns error"));
mtx_unlock(&Giant);
dev_relthread(dev);
if ((m[reqpage]->flags & PG_FICTITIOUS) != 0) {