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;; ;;
;; Copyright (C) KolibriOS team 2011-2012. All rights reserved. ;;
;; Distributed under terms of the GNU General Public License ;;
;; ;;
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$Revision: 3742 $
; This function is intended to replace the old 'hd_read' function when
; [hdd_appl_data] = 0, so its input/output parameters are the same, except
; that it can't use the global variables 'hd_error' and 'hdd_appl_data'.
; in: eax = sector, ebx = buffer, ebp = pointer to PARTITION structure
; eax is relative to partition start
; out: eax = error code; 0 = ok
fs_read32_sys:
; Save ecx, set ecx to SysCache and let the common part do its work.
push ecx
mov ecx, [ebp+PARTITION.Disk]
add ecx, DISK.SysCache
jmp fs_read32_common
; This function is intended to replace the old 'hd_read' function when
; [hdd_appl_data] = 1, so its input/output parameters are the same, except
; that it can't use the global variables 'hd_error' and 'hdd_appl_data'.
; in: eax = sector, ebx = buffer, ebp = pointer to PARTITION structure
; eax is relative to partition start
; out: eax = error code; 0 = ok
fs_read32_app:
; Save ecx, set ecx to AppCache and let the common part do its work.
push ecx
mov ecx, [ebp+PARTITION.Disk]
add ecx, DISK.AppCache
; This label is the common part of fs_read32_sys and fs_read32_app.
fs_read32_common:
; 1. Check that the required sector is inside the partition. If no, return
; DISK_STATUS_END_OF_MEDIA.
cmp dword [ebp+PARTITION.Length+4], 0
jnz @f
cmp dword [ebp+PARTITION.Length], eax
ja @f
mov eax, DISK_STATUS_END_OF_MEDIA
pop ecx
ret
@@:
; 2. Get the absolute sector on the disk.
push edx esi
xor edx, edx
add eax, dword [ebp+PARTITION.FirstSector]
adc edx, dword [ebp+PARTITION.FirstSector+4]
; 3. If there is no cache for this disk, just pass the request to the driver.
cmp [ecx+DISKCACHE.pointer], 0
jnz .scancache
push 1
push esp ; numsectors
push edx ; startsector
push eax ; startsector
push ebx ; buffer
mov esi, [ebp+PARTITION.Disk]
mov al, DISKFUNC.read
call disk_call_driver
pop ecx
pop esi edx
pop ecx
ret
.scancache:
; 4. Scan the cache.
push edi ecx ; scan cache
push edx eax
virtual at esp
.sector_lo dd ?
.sector_hi dd ?
.cache dd ?
end virtual
; The following code is inherited from hd_read. The differences are:
; all code is protected by the cache lock; instead of static calls
; to hd_read_dma/hd_read_pio/bd_read the dynamic call to DISKFUNC.read is used;
; sector is 64-bit, not 32-bit.
call mutex_lock
mov eax, [.sector_lo]
mov edx, [.sector_hi]
mov esi, [ecx+DISKCACHE.pointer]
mov ecx, [ecx+DISKCACHE.sad_size]
add esi, 12
mov edi, 1
.hdreadcache:
cmp dword [esi+8], 0 ; empty
je .nohdcache
cmp [esi], eax ; correct sector
jne .nohdcache
cmp [esi+4], edx ; correct sector
je .yeshdcache
.nohdcache:
add esi, 12
inc edi
dec ecx
jnz .hdreadcache
mov esi, [.cache]
call find_empty_slot64 ; ret in edi
test eax, eax
jnz .read_done
push 1
push esp
push edx
push [.sector_lo+12]
mov ecx, [.cache+16]
mov eax, edi
shl eax, 9
add eax, [ecx+DISKCACHE.data]
push eax
mov esi, [ebp+PARTITION.Disk]
mov al, DISKFUNC.read
call disk_call_driver
pop ecx
dec ecx
jnz .read_done
mov ecx, [.cache]
lea eax, [edi*3]
mov esi, [ecx+DISKCACHE.pointer]
lea esi, [eax*4+esi]
mov eax, [.sector_lo]
mov edx, [.sector_hi]
mov [esi], eax ; sector number
mov [esi+4], edx ; sector number
mov dword [esi+8], 1; hd read - mark as same as in hd
.yeshdcache:
mov esi, edi
mov ecx, [.cache]
shl esi, 9
add esi, [ecx+DISKCACHE.data]
mov edi, ebx
mov ecx, 512/4
rep movsd ; move data
xor eax, eax ; successful read
.read_done:
mov ecx, [.cache]
push eax
call mutex_unlock
pop eax
add esp, 12
pop edi esi edx ecx
ret
; This function is intended to replace the old 'hd_write' function when
; [hdd_appl_data] = 0, so its input/output parameters are the same, except
; that it can't use the global variables 'hd_error' and 'hdd_appl_data'.
; in: eax = sector, ebx = buffer, ebp = pointer to PARTITION structure
; eax is relative to partition start
; out: eax = error code; 0 = ok
fs_write32_sys:
; Save ecx, set ecx to SysCache and let the common part do its work.
push ecx
mov ecx, [ebp+PARTITION.Disk]
add ecx, DISK.SysCache
jmp fs_write32_common
; This function is intended to replace the old 'hd_write' function when
; [hdd_appl_data] = 1, so its input/output parameters are the same, except
; that it can't use the global variables 'hd_error' and 'hdd_appl_data'.
; in: eax = sector, ebx = buffer, ebp = pointer to PARTITION structure
; eax is relative to partition start
; out: eax = error code; 0 = ok
fs_write32_app:
; Save ecx, set ecx to AppCache and let the common part do its work.
push ecx
mov ecx, [ebp+PARTITION.Disk]
add ecx, DISK.AppCache
; This label is the common part of fs_read32_sys and fs_read32_app.
fs_write32_common:
; 1. Check that the required sector is inside the partition. If no, return
; DISK_STATUS_END_OF_MEDIA.
cmp dword [ebp+PARTITION.Length+4], 0
jnz @f
cmp dword [ebp+PARTITION.Length], eax
ja @f
mov eax, DISK_STATUS_END_OF_MEDIA
pop ecx
ret
@@:
push edx esi
; 2. Get the absolute sector on the disk.
xor edx, edx
add eax, dword [ebp+PARTITION.FirstSector]
adc edx, dword [ebp+PARTITION.FirstSector+4]
; 3. If there is no cache for this disk, just pass request to the driver.
cmp [ecx+DISKCACHE.pointer], 0
jnz .scancache
push 1
push esp ; numsectors
push edx ; startsector
push eax ; startsector
push ebx ; buffer
mov esi, [ebp+PARTITION.Disk]
mov al, DISKFUNC.write
call disk_call_driver
pop ecx
pop esi edx
pop ecx
ret
.scancache:
; 4. Scan the cache.
push edi ecx ; scan cache
push edx eax
virtual at esp
.sector_lo dd ?
.sector_hi dd ?
.cache dd ?
end virtual
; The following code is inherited from hd_write. The differences are:
; all code is protected by the cache lock;
; sector is 64-bit, not 32-bit.
call mutex_lock
; check if the cache already has the sector and overwrite it
mov eax, [.sector_lo]
mov edx, [.sector_hi]
mov esi, [ecx+DISKCACHE.pointer]
mov ecx, [ecx+DISKCACHE.sad_size]
add esi, 12
mov edi, 1
.hdwritecache:
cmp dword [esi+8], 0 ; if cache slot is empty
je .not_in_cache_write
cmp [esi], eax ; if the slot has the sector
jne .not_in_cache_write
cmp [esi+4], edx ; if the slot has the sector
je .yes_in_cache_write
.not_in_cache_write:
add esi, 12
inc edi
dec ecx
jnz .hdwritecache
; sector not found in cache
; write the block to a new location
mov esi, [.cache]
call find_empty_slot64 ; ret in edi
test eax, eax
jne .hd_write_access_denied
mov ecx, [.cache]
lea eax, [edi*3]
mov esi, [ecx+DISKCACHE.pointer]
lea esi, [eax*4+esi]
mov eax, [.sector_lo]
mov edx, [.sector_hi]
mov [esi], eax ; sector number
mov [esi+4], edx ; sector number
.yes_in_cache_write:
mov dword [esi+8], 2 ; write - differs from hd
shl edi, 9
mov ecx, [.cache]
add edi, [ecx+DISKCACHE.data]
mov esi, ebx
mov ecx, 512/4
rep movsd ; move data
xor eax, eax ; success
.hd_write_access_denied:
mov ecx, [.cache]
push eax
call mutex_unlock
pop eax
add esp, 12
pop edi esi edx ecx
ret
; This internal function is called from fs_read32_* and fs_write32_*. It is the
; analogue of find_empty_slot for 64-bit sectors.
find_empty_slot64:
;-----------------------------------------------------------
; find empty or read slot, flush cache if next 12.5% is used by write
; output : edi = cache slot
;-----------------------------------------------------------
.search_again:
mov ecx, [esi+DISKCACHE.sad_size]
mov edi, [esi+DISKCACHE.search_start]
shr ecx, 3
.search_for_empty:
inc edi
cmp edi, [esi+DISKCACHE.sad_size]
jbe .inside_cache
mov edi, 1
.inside_cache:
lea eax, [edi*3]
shl eax, 2
add eax, [esi+DISKCACHE.pointer]
cmp dword [eax+8], 2
jb .found_slot ; it's empty or read
dec ecx
jnz .search_for_empty
stdcall write_cache64, [ebp+PARTITION.Disk] ; no empty slots found, write all
test eax, eax
jne .found_slot_access_denied
jmp .search_again ; and start again
.found_slot:
mov [esi+DISKCACHE.search_start], edi
xor eax, eax ; success
.found_slot_access_denied:
ret
; This function is intended to replace the old 'write_cache' function.
proc write_cache64 uses ecx edx esi edi, disk:dword
locals
cache_chain_started dd 0
cache_chain_size dd ?
cache_chain_pos dd ?
cache_chain_ptr dd ?
endl
saved_esi_pos = 16+12 ; size of local variables + size of registers before esi
; If there is no cache for this disk, nothing to do.
cmp [esi+DISKCACHE.pointer], 0
jz .flush
;-----------------------------------------------------------
; write all changed sectors to disk
;-----------------------------------------------------------
; write difference ( 2 ) from cache to DISK
mov ecx, [esi+DISKCACHE.sad_size]
mov esi, [esi+DISKCACHE.pointer]
add esi, 12
mov edi, 1
.write_cache_more:
cmp dword [esi+8], 2 ; if cache slot is not different
jne .write_chain
mov dword [esi+8], 1 ; same as in hd
mov eax, [esi]
mov edx, [esi+4] ; edx:eax = sector to write
; Объединяем запись цепочки последовательных секторов в одно обращение к диску
cmp ecx, 1
jz .nonext
cmp dword [esi+12+8], 2
jnz .nonext
push eax edx
add eax, 1
adc edx, 0
cmp eax, [esi+12]
jnz @f
cmp edx, [esi+12+4]
@@:
pop edx eax
jnz .nonext
cmp [cache_chain_started], 1
jz @f
mov [cache_chain_started], 1
mov [cache_chain_size], 0
mov [cache_chain_pos], edi
mov [cache_chain_ptr], esi
@@:
inc [cache_chain_size]
cmp [cache_chain_size], 16
jnz .continue
jmp .write_chain
.nonext:
call .flush_cache_chain
test eax, eax
jnz .nothing
mov [cache_chain_size], 1
mov [cache_chain_ptr], esi
call .write_cache_sector
test eax, eax
jnz .nothing
jmp .continue
.write_chain:
call .flush_cache_chain
test eax, eax
jnz .nothing
.continue:
add esi, 12
inc edi
dec ecx
jnz .write_cache_more
call .flush_cache_chain
test eax, eax
jnz .nothing
.flush:
mov esi, [disk]
mov al, DISKFUNC.flush
call disk_call_driver
.nothing:
ret
.flush_cache_chain:
xor eax, eax
cmp [cache_chain_started], eax
jz @f
call .write_cache_chain
mov [cache_chain_started], 0
@@:
retn
.write_cache_sector:
mov [cache_chain_size], 1
mov [cache_chain_pos], edi
.write_cache_chain:
pusha
mov edi, [cache_chain_pos]
mov ecx, [ebp-saved_esi_pos]
shl edi, 9
add edi, [ecx+DISKCACHE.data]
mov ecx, [cache_chain_size]
push ecx
push esp ; numsectors
mov eax, [cache_chain_ptr]
pushd [eax+4]
pushd [eax] ; startsector
push edi ; buffer
mov esi, [ebp]
mov esi, [esi+PARTITION.Disk]
mov al, DISKFUNC.write
call disk_call_driver
pop ecx
mov [esp+28], eax
popa
retn
endp
; This internal function is called from disk_add to initialize the caching for
; a new DISK.
; The algorithm is inherited from getcache.inc: take 1/32 part of the available
; physical memory, round down to 8 pages, limit by 128K from below and by 1M
; from above. Reserve 1/8 part of the cache for system data and 7/8 for app
; data.
; After the size is calculated, but before the cache is allocated, the device
; driver can adjust the size. In particular, setting size to zero disables
; caching: there is no sense in a cache for a ramdisk. In fact, such action
; is most useful example of a non-trivial adjustment.
; esi = pointer to DISK structure
disk_init_cache:
; 1. Calculate the suggested cache size.
; 1a. Get the size of free physical memory in pages.
mov eax, [pg_data.pages_free]
; 1b. Use the value to calculate the size.
shl eax, 12 - 5 ; 1/32 of it in bytes
and eax, -8*4096 ; round down to the multiple of 8 pages
; 1c. Force lower and upper limits.
cmp eax, 1024*1024
jb @f
mov eax, 1024*1024
@@:
cmp eax, 128*1024
ja @f
mov eax, 128*1024
@@:
; 1d. Give a chance to the driver to adjust the size.
push eax
mov al, DISKFUNC.adjust_cache_size
call disk_call_driver
; Cache size calculated.
mov [esi+DISK.cache_size], eax
test eax, eax
jz .nocache
; 2. Allocate memory for the cache.
; 2a. Call the allocator.
stdcall kernel_alloc, eax
test eax, eax
jnz @f
; 2b. If it failed, say a message and return with eax = 0.
dbgstr 'no memory for disk cache'
jmp .nothing
@@:
; 3. Fill two DISKCACHE structures.
mov [esi+DISK.SysCache.pointer], eax
lea ecx, [esi+DISK.SysCache.mutex]
call mutex_init
lea ecx, [esi+DISK.AppCache.mutex]
call mutex_init
; The following code is inherited from getcache.inc.
mov edx, [esi+DISK.SysCache.pointer]
and [esi+DISK.SysCache.search_start], 0
and [esi+DISK.AppCache.search_start], 0
mov eax, [esi+DISK.cache_size]
shr eax, 3
mov [esi+DISK.SysCache.data_size], eax
add edx, eax
imul eax, 7
mov [esi+DISK.AppCache.data_size], eax
mov [esi+DISK.AppCache.pointer], edx
mov eax, [esi+DISK.SysCache.data_size]
push ebx
call calculate_for_hd64
pop ebx
add eax, [esi+DISK.SysCache.pointer]
mov [esi+DISK.SysCache.data], eax
mov [esi+DISK.SysCache.sad_size], ecx
push edi
mov edi, [esi+DISK.SysCache.pointer]
lea ecx, [ecx*3]
xor eax, eax
rep stosd
pop edi
mov eax, [esi+DISK.AppCache.data_size]
push ebx
call calculate_for_hd64
pop ebx
add eax, [esi+DISK.AppCache.pointer]
mov [esi+DISK.AppCache.data], eax
mov [esi+DISK.AppCache.sad_size], ecx
push edi
mov edi, [esi+DISK.AppCache.pointer]
lea ecx, [ecx*3]
xor eax, eax
rep stosd
pop edi
; 4. Return with nonzero al.
mov al, 1
; 5. Return.
.nothing:
ret
; No caching is required for this driver. Zero cache pointers and return with
; nonzero al.
.nocache:
mov [esi+DISK.SysCache.pointer], eax
mov [esi+DISK.AppCache.pointer], eax
mov al, 1
ret
calculate_for_hd64:
push eax
mov ebx, eax
shr eax, 9
lea eax, [eax*3]
shl eax, 2
sub ebx, eax
shr ebx, 9
mov ecx, ebx
shl ebx, 9
pop eax
sub eax, ebx
dec ecx
ret
; This internal function is called from disk_media_dereference to free the
; allocated cache, if there is one.
; esi = pointer to DISK structure
disk_free_cache:
; The algorithm is straightforward.
mov eax, [esi+DISK.SysCache.pointer]
test eax, eax
jz .nothing
stdcall kernel_free, eax
.nothing:
ret
; This function flushes all modified data from both caches for the given DISK.
; esi = pointer to DISK
disk_sync:
; The algorithm is straightforward.
push esi
push esi ; for second write_cache64
push esi ; for first write_cache64
add esi, DISK.SysCache
call write_cache64
add esi, DISK.AppCache - DISK.SysCache
call write_cache64
pop esi
ret