s390/cio: remove unneeded DMA zone allocation

JIRA: https://issues.redhat.com/browse/RHEL-86670

commit a3a64a4
Author: Peter Oberparleiter <[email protected]>
Date:   Thu Jan 18 16:09:39 2024 +0100

    s390/cio: remove unneeded DMA zone allocation

    Remove GFP_DMA flag when allocating memory to be used for CHSC control
    blocks. The CHSC instruction can access memory beyond the DMA zone.

    Suggested-by: Heiko Carstens <[email protected]>
    Reviewed-by: Vineeth Vijayan <[email protected]>
    Signed-off-by: Peter Oberparleiter <[email protected]>
    Signed-off-by: Heiko Carstens <[email protected]>

Signed-off-by: Thomas Huth <[email protected]>

Author: huth

drivers/s390/cio/chsc.c

@@ -1128,8 +1128,8 @@ int __init chsc_init(void)
 {
 	int ret;
 
-	sei_page = (void *)get_zeroed_page(GFP_KERNEL | GFP_DMA);
-	chsc_page = (void *)get_zeroed_page(GFP_KERNEL | GFP_DMA);
+	sei_page = (void *)get_zeroed_page(GFP_KERNEL);
+	chsc_page = (void *)get_zeroed_page(GFP_KERNEL);
 	if (!sei_page || !chsc_page) {
 		ret = -ENOMEM;
 		goto out_err;

drivers/s390/cio/chsc_sch.c

@@ -293,7 +293,7 @@ static int chsc_ioctl_start(void __user *user_area)
 	if (!css_general_characteristics.dynio)
 		/* It makes no sense to try. */
 		return -EOPNOTSUPP;
-	chsc_area = (void *)get_zeroed_page(GFP_DMA | GFP_KERNEL);
+	chsc_area = (void *)get_zeroed_page(GFP_KERNEL);
 	if (!chsc_area)
 		return -ENOMEM;
 	request = kzalloc(sizeof(*request), GFP_KERNEL);
@@ -341,7 +341,7 @@ static int chsc_ioctl_on_close_set(void __user *user_area)
 		ret = -ENOMEM;
 		goto out_unlock;
 	}
-	on_close_chsc_area = (void *)get_zeroed_page(GFP_DMA | GFP_KERNEL);
+	on_close_chsc_area = (void *)get_zeroed_page(GFP_KERNEL);
 	if (!on_close_chsc_area) {
 		ret = -ENOMEM;
 		goto out_free_request;
@@ -393,7 +393,7 @@ static int chsc_ioctl_start_sync(void __user *user_area)
 	struct chsc_sync_area *chsc_area;
 	int ret, ccode;
 
-	chsc_area = (void *)get_zeroed_page(GFP_KERNEL | GFP_DMA);
+	chsc_area = (void *)get_zeroed_page(GFP_KERNEL);
 	if (!chsc_area)
 		return -ENOMEM;
 	if (copy_from_user(chsc_area, user_area, PAGE_SIZE)) {
@@ -439,7 +439,7 @@ static int chsc_ioctl_info_channel_path(void __user *user_cd)
 		u8 data[PAGE_SIZE - 20];
 	} __attribute__ ((packed)) *scpcd_area;
 
-	scpcd_area = (void *)get_zeroed_page(GFP_KERNEL | GFP_DMA);
+	scpcd_area = (void *)get_zeroed_page(GFP_KERNEL);
 	if (!scpcd_area)
 		return -ENOMEM;
 	cd = kzalloc(sizeof(*cd), GFP_KERNEL);
@@ -501,7 +501,7 @@ static int chsc_ioctl_info_cu(void __user *user_cd)
 		u8 data[PAGE_SIZE - 20];
 	} __attribute__ ((packed)) *scucd_area;
 
-	scucd_area = (void *)get_zeroed_page(GFP_KERNEL | GFP_DMA);
+	scucd_area = (void *)get_zeroed_page(GFP_KERNEL);
 	if (!scucd_area)
 		return -ENOMEM;
 	cd = kzalloc(sizeof(*cd), GFP_KERNEL);
@@ -564,7 +564,7 @@ static int chsc_ioctl_info_sch_cu(void __user *user_cud)
 		u8 data[PAGE_SIZE - 20];
 	} __attribute__ ((packed)) *sscud_area;
 
-	sscud_area = (void *)get_zeroed_page(GFP_KERNEL | GFP_DMA);
+	sscud_area = (void *)get_zeroed_page(GFP_KERNEL);
 	if (!sscud_area)
 		return -ENOMEM;
 	cud = kzalloc(sizeof(*cud), GFP_KERNEL);
@@ -626,7 +626,7 @@ static int chsc_ioctl_conf_info(void __user *user_ci)
 		u8 data[PAGE_SIZE - 20];
 	} __attribute__ ((packed)) *sci_area;
 
-	sci_area = (void *)get_zeroed_page(GFP_KERNEL | GFP_DMA);
+	sci_area = (void *)get_zeroed_page(GFP_KERNEL);
 	if (!sci_area)
 		return -ENOMEM;
 	ci = kzalloc(sizeof(*ci), GFP_KERNEL);
@@ -697,7 +697,7 @@ static int chsc_ioctl_conf_comp_list(void __user *user_ccl)
 		u32 res;
 	} __attribute__ ((packed)) *cssids_parm;
 
-	sccl_area = (void *)get_zeroed_page(GFP_KERNEL | GFP_DMA);
+	sccl_area = (void *)get_zeroed_page(GFP_KERNEL);
 	if (!sccl_area)
 		return -ENOMEM;
 	ccl = kzalloc(sizeof(*ccl), GFP_KERNEL);
@@ -757,7 +757,7 @@ static int chsc_ioctl_chpd(void __user *user_chpd)
 	int ret;
 
 	chpd = kzalloc(sizeof(*chpd), GFP_KERNEL);
-	scpd_area = (void *)get_zeroed_page(GFP_KERNEL | GFP_DMA);
+	scpd_area = (void *)get_zeroed_page(GFP_KERNEL);
 	if (!scpd_area || !chpd) {
 		ret = -ENOMEM;
 		goto out_free;
@@ -797,7 +797,7 @@ static int chsc_ioctl_dcal(void __user *user_dcal)
 		u8 data[PAGE_SIZE - 36];
 	} __attribute__ ((packed)) *sdcal_area;
 
-	sdcal_area = (void *)get_zeroed_page(GFP_KERNEL | GFP_DMA);
+	sdcal_area = (void *)get_zeroed_page(GFP_KERNEL);
 	if (!sdcal_area)
 		return -ENOMEM;
 	dcal = kzalloc(sizeof(*dcal), GFP_KERNEL);

drivers/s390/cio/scm.c

@@ -228,7 +228,7 @@ int scm_update_information(void)
 	size_t num;
 	int ret;
 
-	scm_info = (void *)__get_free_page(GFP_KERNEL | GFP_DMA);
+	scm_info = (void *)__get_free_page(GFP_KERNEL);
 	if (!scm_info)
 		return -ENOMEM;