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Date: Fri, 11 Jan 2008 12:58:05 +0100
From: Borislav Petkov <bbpetkov@...oo.de>
To: Bartlomiej@...lum.tnic, Zolnierkiewicz@...lum.tnic,
<bzolnier@...il.com>
Cc: linux-kernel@...r.kernel.org, linux-ide@...r.kernel.org,
Borislav Petkov <bbpetkov@...oo.de>
Subject: [PATCH 07/21] ide-floppy: remove struct idefloppy_capacity_descriptor
We test here for updated capacity descriptors by checking whether the media
has changed instead of memcmp-ing with a cached copy of the capacity
descriptors.
Also:
- remove one of 2 consecutive if (!i)-tests.
- start loop at 1 in idefloppy_get_format_capacities() since userspace doesn't
need the current/maximum capacity descriptor. i.e the first one.
- fix comments formatting
Signed-off-by: Borislav Petkov <bbpetkov@...oo.de>
---
drivers/ide/ide-floppy.c | 132 +++++++++++++++++----------------------------
1 files changed, 50 insertions(+), 82 deletions(-)
diff --git a/drivers/ide/ide-floppy.c b/drivers/ide/ide-floppy.c
index 679d48e..5c85833 100644
--- a/drivers/ide/ide-floppy.c
+++ b/drivers/ide/ide-floppy.c
@@ -119,29 +119,7 @@ typedef struct idefloppy_packet_command_s {
#define PC_SUPPRESS_ERROR 6 /* Suppress error reporting */
-/*
- * Format capacity
- */
-typedef struct {
- u8 reserved[3];
- u8 length; /* Length of the following descriptors in bytes */
-} idefloppy_capacity_header_t;
-
-typedef struct {
- u32 blocks; /* Number of blocks */
-#if defined(__LITTLE_ENDIAN_BITFIELD)
- unsigned dc :2; /* Descriptor Code */
- unsigned reserved :6;
-#elif defined(__BIG_ENDIAN_BITFIELD)
- unsigned reserved :6;
- unsigned dc :2; /* Descriptor Code */
-#else
-#error "Bitfield endianness not defined! Check your byteorder.h"
-#endif
- u8 length_msb; /* Block Length (MSB)*/
- u16 length; /* Block Length */
-} idefloppy_capacity_descriptor_t;
-
+/* format capacities descriptor codes */
#define CAPACITY_INVALID 0x00
#define CAPACITY_UNFORMATTED 0x01
#define CAPACITY_CURRENT 0x02
@@ -184,8 +162,6 @@ typedef struct ide_floppy_obj {
*/
/* Current format */
int blocks, block_size, bs_factor;
- /* Last format capacity */
- idefloppy_capacity_descriptor_t capacity;
/* Write protect */
int wp;
/* Supports format progress report */
@@ -1229,17 +1205,16 @@ static int idefloppy_get_sfrp_bit(ide_drive_t *drive)
}
/*
- * Determine if a media is present in the floppy drive, and if so,
- * its LBA capacity.
+ * Determine if a media is present in the floppy drive, and if so, its LBA
+ * capacity.
*/
-static int idefloppy_get_capacity (ide_drive_t *drive)
+static int idefloppy_get_capacity(ide_drive_t *drive)
{
idefloppy_floppy_t *floppy = drive->driver_data;
idefloppy_pc_t pc;
- idefloppy_capacity_header_t *header;
- idefloppy_capacity_descriptor_t *descriptor;
- int i, descriptors, rc = 1, blocks, length;
-
+ int i, desc_cnt, rc = 1, blocks, length;
+ u8 header_len;
+
drive->bios_cyl = 0;
drive->bios_head = drive->bios_sect = 0;
floppy->blocks = 0;
@@ -1251,17 +1226,17 @@ static int idefloppy_get_capacity (ide_drive_t *drive)
printk(KERN_ERR "ide-floppy: Can't get floppy parameters\n");
return 1;
}
- header = (idefloppy_capacity_header_t *) pc.buffer;
- descriptors = header->length / sizeof(idefloppy_capacity_descriptor_t);
- descriptor = (idefloppy_capacity_descriptor_t *) (header + 1);
+ header_len = pc.buffer[3];
+ desc_cnt = header_len / 8; /* capacity descriptor of 8 bytes */
- for (i = 0; i < descriptors; i++, descriptor++) {
- blocks = descriptor->blocks = be32_to_cpu(descriptor->blocks);
- length = descriptor->length = be16_to_cpu(descriptor->length);
+ for (i = 0; i < desc_cnt; i++) {
+ unsigned int desc_start = 4 + i*8;
+ blocks = be32_to_cpu(*(u32 *)&pc.buffer[desc_start]);
+ length = be16_to_cpu(*(u16 *)&pc.buffer[desc_start + 6]);
- if (!i)
+ if (!i)
{
- switch (descriptor->dc) {
+ switch (pc.buffer[desc_start + 4] & 0x03) {
/* Clik! drive returns this instead of CAPACITY_CURRENT */
case CAPACITY_UNFORMATTED:
if (!test_bit(IDEFLOPPY_CLIK_DRIVE, &floppy->flags))
@@ -1272,11 +1247,11 @@ static int idefloppy_get_capacity (ide_drive_t *drive)
break;
case CAPACITY_CURRENT:
/* Normal Zip/LS-120 disks */
- if (memcmp(descriptor, &floppy->capacity, sizeof (idefloppy_capacity_descriptor_t)))
+ if ((1UL << IDEFLOPPY_MEDIA_CHANGED) & floppy->flags)
printk(KERN_INFO "%s: %dkB, %d blocks, %d "
"sector size\n", drive->name,
blocks * length / 1024, blocks, length);
- floppy->capacity = *descriptor;
+
if (!length || length % 512) {
printk(KERN_NOTICE "%s: %d bytes block size "
"not supported\n", drive->name, length);
@@ -1303,9 +1278,8 @@ static int idefloppy_get_capacity (ide_drive_t *drive)
"in drive\n", drive->name);
break;
}
- }
- if (!i) {
- debug_log("Descriptor 0 Code: %d\n", descriptor->dc);
+ debug_log("Descriptor 0 Code: %d\n",
+ pc.buffer[desc_start + 4] & 0x03);
}
debug_log("Descriptor %d: %dkB, %d blocks, %d sector size\n",
i, blocks * length / 1024, blocks, length);
@@ -1321,35 +1295,32 @@ static int idefloppy_get_capacity (ide_drive_t *drive)
}
/*
-** Obtain the list of formattable capacities.
-** Very similar to idefloppy_get_capacity, except that we push the capacity
-** descriptors to userland, instead of our own structures.
-**
-** Userland gives us the following structure:
-**
-** struct idefloppy_format_capacities {
-** int nformats;
-** struct {
-** int nblocks;
-** int blocksize;
-** } formats[];
-** } ;
-**
-** userland initializes nformats to the number of allocated formats[]
-** records. On exit we set nformats to the number of records we've
-** actually initialized.
-**
-*/
+ * Obtain the list of formattable capacities.
+ * Very similar to idefloppy_get_capacity, except that we push the capacity
+ * descriptors to userland, instead of our own structures.
+ *
+ * Userland gives us the following structure:
+ *
+ * struct idefloppy_format_capacities {
+ * int nformats;
+ * struct {
+ * int nblocks;
+ * int blocksize;
+ * } formats[];
+ * } ;
+ *
+ * userland initializes nformats to the number of allocated formats[]
+ * records. On exit we set nformats to the number of records we've
+ * actually initialized.
+ *
+ */
static int idefloppy_get_format_capacities(ide_drive_t *drive, int __user *arg)
{
idefloppy_pc_t pc;
- idefloppy_capacity_header_t *header;
- idefloppy_capacity_descriptor_t *descriptor;
- int i, descriptors, blocks, length;
- int u_array_size;
- int u_index;
+ int i, desc_cnt, blocks, length, u_array_size, u_index;
int __user *argp;
+ u8 header_len;
if (get_user(u_array_size, arg))
return (-EFAULT);
@@ -1362,28 +1333,25 @@ static int idefloppy_get_format_capacities(ide_drive_t *drive, int __user *arg)
printk(KERN_ERR "ide-floppy: Can't get floppy parameters\n");
return (-EIO);
}
- header = (idefloppy_capacity_header_t *) pc.buffer;
- descriptors = header->length /
- sizeof(idefloppy_capacity_descriptor_t);
- descriptor = (idefloppy_capacity_descriptor_t *) (header + 1);
+ header_len = pc.buffer[3];
+ desc_cnt = header_len / 8; /* capacity descriptor of 8 bytes */
u_index = 0;
argp = arg + 1;
/*
- ** We always skip the first capacity descriptor. That's the
- ** current capacity. We are interested in the remaining descriptors,
- ** the formattable capacities.
- */
+ * We always skip the first capacity descriptor. That's the current
+ * capacity. We are interested in the remaining descriptors, the
+ * formattable capacities.
+ */
+ for (i = 1; i < desc_cnt; i++) {
+ unsigned int desc_start = 4 + i*8;
- for (i=0; i<descriptors; i++, descriptor++) {
if (u_index >= u_array_size)
break; /* User-supplied buffer too small */
- if (i == 0)
- continue; /* Skip the first descriptor */
- blocks = be32_to_cpu(descriptor->blocks);
- length = be16_to_cpu(descriptor->length);
+ blocks = be32_to_cpu(*(u32 *)&pc.buffer[desc_start]);
+ length = be16_to_cpu(*(u16 *)&pc.buffer[desc_start + 6]);
if (put_user(blocks, argp))
return(-EFAULT);
--
1.5.3.7
--
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