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path: root/drivers/scsi/sg.c
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Diffstat (limited to 'drivers/scsi/sg.c')
-rw-r--r--drivers/scsi/sg.c76
1 files changed, 52 insertions, 24 deletions
diff --git a/drivers/scsi/sg.c b/drivers/scsi/sg.c
index 34f9343ed0af..81e3bc7b02a1 100644
--- a/drivers/scsi/sg.c
+++ b/drivers/scsi/sg.c
@@ -60,7 +60,7 @@ static int sg_version_num = 30534; /* 2 digits for each component */
#ifdef CONFIG_SCSI_PROC_FS
#include <linux/proc_fs.h>
-static char *sg_version_date = "20060818";
+static char *sg_version_date = "20061027";
static int sg_proc_init(void);
static void sg_proc_cleanup(void);
@@ -94,6 +94,9 @@ int sg_big_buff = SG_DEF_RESERVED_SIZE;
static int def_reserved_size = -1; /* picks up init parameter */
static int sg_allow_dio = SG_ALLOW_DIO_DEF;
+static int scatter_elem_sz = SG_SCATTER_SZ;
+static int scatter_elem_sz_prev = SG_SCATTER_SZ;
+
#define SG_SECTOR_SZ 512
#define SG_SECTOR_MSK (SG_SECTOR_SZ - 1)
@@ -707,12 +710,12 @@ sg_common_write(Sg_fd * sfp, Sg_request * srp,
(int) cmnd[0], (int) hp->cmd_len));
if ((k = sg_start_req(srp))) {
- SCSI_LOG_TIMEOUT(1, printk("sg_write: start_req err=%d\n", k));
+ SCSI_LOG_TIMEOUT(1, printk("sg_common_write: start_req err=%d\n", k));
sg_finish_rem_req(srp);
return k; /* probably out of space --> ENOMEM */
}
if ((k = sg_write_xfer(srp))) {
- SCSI_LOG_TIMEOUT(1, printk("sg_write: write_xfer, bad address\n"));
+ SCSI_LOG_TIMEOUT(1, printk("sg_common_write: write_xfer, bad address\n"));
sg_finish_rem_req(srp);
return k;
}
@@ -743,7 +746,7 @@ sg_common_write(Sg_fd * sfp, Sg_request * srp,
hp->dxfer_len, srp->data.k_use_sg, timeout,
SG_DEFAULT_RETRIES, srp, sg_cmd_done,
GFP_ATOMIC)) {
- SCSI_LOG_TIMEOUT(1, printk("sg_write: scsi_execute_async failed\n"));
+ SCSI_LOG_TIMEOUT(1, printk("sg_common_write: scsi_execute_async failed\n"));
/*
* most likely out of mem, but could also be a bad map
*/
@@ -1280,7 +1283,7 @@ sg_cmd_done(void *data, char *sense, int result, int resid)
sg_finish_rem_req(srp);
srp = NULL;
if (NULL == sfp->headrp) {
- SCSI_LOG_TIMEOUT(1, printk("sg...bh: already closed, final cleanup\n"));
+ SCSI_LOG_TIMEOUT(1, printk("sg_cmd_done: already closed, final cleanup\n"));
if (0 == sg_remove_sfp(sdp, sfp)) { /* device still present */
scsi_device_put(sdp->device);
}
@@ -1509,12 +1512,12 @@ sg_remove(struct class_device *cl_dev, struct class_interface *cl_intf)
POLL_HUP);
}
}
- SCSI_LOG_TIMEOUT(3, printk("sg_detach: dev=%d, dirty\n", k));
+ SCSI_LOG_TIMEOUT(3, printk("sg_remove: dev=%d, dirty\n", k));
if (NULL == sdp->headfp) {
sg_dev_arr[k] = NULL;
}
} else { /* nothing active, simple case */
- SCSI_LOG_TIMEOUT(3, printk("sg_detach: dev=%d\n", k));
+ SCSI_LOG_TIMEOUT(3, printk("sg_remove: dev=%d\n", k));
sg_dev_arr[k] = NULL;
}
sg_nr_dev--;
@@ -1537,11 +1540,9 @@ sg_remove(struct class_device *cl_dev, struct class_interface *cl_intf)
msleep(10); /* dirty detach so delay device destruction */
}
-/* Set 'perm' (4th argument) to 0 to disable module_param's definition
- * of sysfs parameters (which module_param doesn't yet support).
- * Sysfs parameters defined explicitly below.
- */
-module_param_named(def_reserved_size, def_reserved_size, int, S_IRUGO);
+module_param_named(scatter_elem_sz, scatter_elem_sz, int, S_IRUGO | S_IWUSR);
+module_param_named(def_reserved_size, def_reserved_size, int,
+ S_IRUGO | S_IWUSR);
module_param_named(allow_dio, sg_allow_dio, int, S_IRUGO | S_IWUSR);
MODULE_AUTHOR("Douglas Gilbert");
@@ -1550,6 +1551,8 @@ MODULE_LICENSE("GPL");
MODULE_VERSION(SG_VERSION_STR);
MODULE_ALIAS_CHARDEV_MAJOR(SCSI_GENERIC_MAJOR);
+MODULE_PARM_DESC(scatter_elem_sz, "scatter gather element "
+ "size (default: max(SG_SCATTER_SZ, PAGE_SIZE))");
MODULE_PARM_DESC(def_reserved_size, "size of buffer reserved for each fd");
MODULE_PARM_DESC(allow_dio, "allow direct I/O (default: 0 (disallow))");
@@ -1558,8 +1561,14 @@ init_sg(void)
{
int rc;
+ if (scatter_elem_sz < PAGE_SIZE) {
+ scatter_elem_sz = PAGE_SIZE;
+ scatter_elem_sz_prev = scatter_elem_sz;
+ }
if (def_reserved_size >= 0)
sg_big_buff = def_reserved_size;
+ else
+ def_reserved_size = sg_big_buff;
rc = register_chrdev_region(MKDEV(SCSI_GENERIC_MAJOR, 0),
SG_MAX_DEVS, "sg");
@@ -1842,24 +1851,40 @@ sg_build_indirect(Sg_scatter_hold * schp, Sg_fd * sfp, int buff_size)
if (mx_sc_elems < 0)
return mx_sc_elems; /* most likely -ENOMEM */
+ num = scatter_elem_sz;
+ if (unlikely(num != scatter_elem_sz_prev)) {
+ if (num < PAGE_SIZE) {
+ scatter_elem_sz = PAGE_SIZE;
+ scatter_elem_sz_prev = PAGE_SIZE;
+ } else
+ scatter_elem_sz_prev = num;
+ }
for (k = 0, sg = schp->buffer, rem_sz = blk_size;
(rem_sz > 0) && (k < mx_sc_elems);
++k, rem_sz -= ret_sz, ++sg) {
- num = (rem_sz > SG_SCATTER_SZ) ? SG_SCATTER_SZ : rem_sz;
+ num = (rem_sz > scatter_elem_sz_prev) ?
+ scatter_elem_sz_prev : rem_sz;
p = sg_page_malloc(num, sfp->low_dma, &ret_sz);
if (!p)
return -ENOMEM;
+ if (num == scatter_elem_sz_prev) {
+ if (unlikely(ret_sz > scatter_elem_sz_prev)) {
+ scatter_elem_sz = ret_sz;
+ scatter_elem_sz_prev = ret_sz;
+ }
+ }
sg->page = p;
- sg->length = ret_sz;
+ sg->length = (ret_sz > num) ? num : ret_sz;
- SCSI_LOG_TIMEOUT(5, printk("sg_build_build: k=%d, a=0x%p, len=%d\n",
- k, p, ret_sz));
+ SCSI_LOG_TIMEOUT(5, printk("sg_build_indirect: k=%d, num=%d, "
+ "ret_sz=%d\n", k, num, ret_sz));
} /* end of for loop */
schp->k_use_sg = k;
- SCSI_LOG_TIMEOUT(5, printk("sg_build_indirect: k_use_sg=%d, rem_sz=%d\n", k, rem_sz));
+ SCSI_LOG_TIMEOUT(5, printk("sg_build_indirect: k_use_sg=%d, "
+ "rem_sz=%d\n", k, rem_sz));
schp->bufflen = blk_size;
if (rem_sz > 0) /* must have failed */
@@ -1990,7 +2015,7 @@ sg_remove_scat(Sg_scatter_hold * schp)
for (k = 0; (k < schp->k_use_sg) && sg->page;
++k, ++sg) {
SCSI_LOG_TIMEOUT(5, printk(
- "sg_remove_scat: k=%d, a=0x%p, len=%d\n",
+ "sg_remove_scat: k=%d, pg=0x%p, len=%d\n",
k, sg->page, sg->length));
sg_page_free(sg->page, sg->length);
}
@@ -2341,6 +2366,9 @@ sg_add_sfp(Sg_device * sdp, int dev)
}
write_unlock_irqrestore(&sg_dev_arr_lock, iflags);
SCSI_LOG_TIMEOUT(3, printk("sg_add_sfp: sfp=0x%p\n", sfp));
+ if (unlikely(sg_big_buff != def_reserved_size))
+ sg_big_buff = def_reserved_size;
+
sg_build_reserve(sfp, sg_big_buff);
SCSI_LOG_TIMEOUT(3, printk("sg_add_sfp: bufflen=%d, k_use_sg=%d\n",
sfp->reserve.bufflen, sfp->reserve.k_use_sg));
@@ -2437,16 +2465,16 @@ sg_res_in_use(Sg_fd * sfp)
return srp ? 1 : 0;
}
-/* If retSzp==NULL want exact size or fail */
+/* The size fetched (value output via retSzp) set when non-NULL return */
static struct page *
sg_page_malloc(int rqSz, int lowDma, int *retSzp)
{
struct page *resp = NULL;
gfp_t page_mask;
int order, a_size;
- int resSz = rqSz;
+ int resSz;
- if (rqSz <= 0)
+ if ((rqSz <= 0) || (NULL == retSzp))
return resp;
if (lowDma)
@@ -2456,8 +2484,9 @@ sg_page_malloc(int rqSz, int lowDma, int *retSzp)
for (order = 0, a_size = PAGE_SIZE; a_size < rqSz;
order++, a_size <<= 1) ;
+ resSz = a_size; /* rounded up if necessary */
resp = alloc_pages(page_mask, order);
- while ((!resp) && order && retSzp) {
+ while ((!resp) && order) {
--order;
a_size >>= 1; /* divide by 2, until PAGE_SIZE */
resp = alloc_pages(page_mask, order); /* try half */
@@ -2466,8 +2495,7 @@ sg_page_malloc(int rqSz, int lowDma, int *retSzp)
if (resp) {
if (!capable(CAP_SYS_ADMIN) || !capable(CAP_SYS_RAWIO))
memset(page_address(resp), 0, resSz);
- if (retSzp)
- *retSzp = resSz;
+ *retSzp = resSz;
}
return resp;
}
generated by cgit v1.2.3 (git 2.39.0) at 2025-02-11 05:04:03 +0300