From 842fbb5173258aaefbc11cdcd9042de042996d02 Mon Sep 17 00:00:00 2001
From: Anton Kling <anton@kling.gg>
Date: Tue, 2 Jul 2024 14:42:00 +0200
Subject: ahci: Bug fix, turns out the async optimization does not work that
well
---
kernel/drivers/ahci.c | 51 +++++++++++++--------------------------------------
1 file changed, 13 insertions(+), 38 deletions(-)
(limited to 'kernel')
diff --git a/kernel/drivers/ahci.c b/kernel/drivers/ahci.c
index 0d379cb..bbb0c22 100644
--- a/kernel/drivers/ahci.c
+++ b/kernel/drivers/ahci.c
@@ -303,23 +303,9 @@ u8 get_free_command_slot(volatile struct HBA_PORT *port, u8 *err) {
return 0;
}
-void ahci_wait_for_completion(volatile struct HBA_PORT *port) {
- u32 num_slots = ((hba->cap >> 8) & 0x1F);
- u32 slots = (port->ci);
- u32 num_free = 0;
- for (; num_free < num_slots;) {
- num_free = 0;
- for (u8 i = 0; i < num_slots + 1; i++) {
- if (!((slots >> i) & 1)) {
- num_free++;
- }
- }
- }
-}
-
// is_write: Determins whether a read or write command will be used.
u8 ahci_perform_command(volatile struct HBA_PORT *port, u32 startl, u32 starth,
- u32 count, u16 *buffer, u8 is_write, u8 async) {
+ u32 count, u16 *buffer, u8 is_write) {
// TODO: The number of PRDT tables are hardcoded at a seemingly
// very low number. It can be up to 65,535. Should it maybe be
// changed?
@@ -394,10 +380,6 @@ u8 ahci_perform_command(volatile struct HBA_PORT *port, u32 startl, u32 starth,
port->ci = 1 << command_slot; // Issue command
- if (async) {
- return 1;
- }
-
// Wait for completion
for (;;) {
// In some longer duration reads, it may be helpful to spin on the DPS bit
@@ -421,13 +403,13 @@ u8 ahci_perform_command(volatile struct HBA_PORT *port, u32 startl, u32 starth,
}
u8 ahci_raw_write(volatile struct HBA_PORT *port, u32 startl, u32 starth,
- u32 count, u16 *inbuffer, u8 async) {
- return ahci_perform_command(port, startl, starth, count, inbuffer, 1, async);
+ u32 count, u16 *inbuffer) {
+ return ahci_perform_command(port, startl, starth, count, inbuffer, 1);
}
u8 ahci_raw_read(volatile struct HBA_PORT *port, u32 startl, u32 starth,
- u32 count, u16 *outbuffer, u8 async) {
- return ahci_perform_command(port, startl, starth, count, outbuffer, 0, async);
+ u32 count, u16 *outbuffer) {
+ return ahci_perform_command(port, startl, starth, count, outbuffer, 0);
}
int ahci_write(u8 *buffer, u64 offset, u64 len, vfs_fd_t *fd) {
@@ -445,13 +427,13 @@ int ahci_write(u8 *buffer, u64 offset, u64 len, vfs_fd_t *fd) {
if (offset > 0) {
u8 tmp_buffer[512];
- ahci_raw_read(&hba->ports[port], lba, 0, 1, (u16 *)tmp_buffer, 0);
+ ahci_raw_read(&hba->ports[port], lba, 0, 1, (u16 *)tmp_buffer);
int left = 512 - offset;
int write = min(left, len);
memcpy(tmp_buffer + offset, buffer, write);
- ahci_raw_write(&hba->ports[port], lba, 0, 1, (u16 *)tmp_buffer, 0);
+ ahci_raw_write(&hba->ports[port], lba, 0, 1, (u16 *)tmp_buffer);
offset = 0;
len -= write;
@@ -460,28 +442,22 @@ int ahci_write(u8 *buffer, u64 offset, u64 len, vfs_fd_t *fd) {
}
for (; sector_count >= num_prdt; lba++) {
- ahci_raw_write(&hba->ports[port], lba, 0, num_prdt, (u16 *)buffer, 1);
+ ahci_raw_write(&hba->ports[port], lba, 0, num_prdt, (u16 *)buffer);
buffer += num_prdt * 512;
len -= num_prdt * 512;
sector_count -= num_prdt;
}
- if (sector_count >= num_prdt) {
- ahci_wait_for_completion(&hba->ports[port]);
- }
-
if (sector_count > 0 && (0 == len % SECTOR_SIZE)) {
- ahci_raw_write(&hba->ports[port], lba, 0, sector_count, (u16 *)buffer, 0);
+ ahci_raw_write(&hba->ports[port], lba, 0, sector_count, (u16 *)buffer);
return rc;
}
if (sector_count > 0 && len > 0) {
u8 tmp_buffer[512 * sector_count];
- ahci_raw_read(&hba->ports[port], lba, 0, sector_count, (u16 *)tmp_buffer,
- 0);
+ ahci_raw_read(&hba->ports[port], lba, 0, sector_count, (u16 *)tmp_buffer);
memcpy(tmp_buffer + offset, buffer, len);
- ahci_raw_write(&hba->ports[port], lba, 0, sector_count, (u16 *)tmp_buffer,
- 0);
+ ahci_raw_write(&hba->ports[port], lba, 0, sector_count, (u16 *)tmp_buffer);
}
return rc;
}
@@ -500,7 +476,7 @@ int ahci_read(u8 *buffer, u64 offset, u64 len, vfs_fd_t *fd) {
}
u8 tmp_buffer[512 * num_prdt];
for (; sector_count >= num_prdt; lba++) {
- ahci_raw_read(&hba->ports[port], lba, 0, num_prdt, (u16 *)tmp_buffer, 0);
+ ahci_raw_read(&hba->ports[port], lba, 0, num_prdt, (u16 *)tmp_buffer);
memcpy(buffer, tmp_buffer + offset, 512 * num_prdt);
offset = 0;
buffer += num_prdt * 512;
@@ -509,8 +485,7 @@ int ahci_read(u8 *buffer, u64 offset, u64 len, vfs_fd_t *fd) {
}
if (sector_count > 0) {
- ahci_raw_read(&hba->ports[port], lba, 0, sector_count, (u16 *)tmp_buffer,
- 0);
+ ahci_raw_read(&hba->ports[port], lba, 0, sector_count, (u16 *)tmp_buffer);
memcpy(buffer, tmp_buffer + offset, len);
}
return rc;
--
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